Meeradevi Kathaliyil - Sustainable Architecture Portfolio

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HOTANDARID

Sunpathdiagramandshading

Southside:Overhangsof2.2 mcanonlybecomean effectiveshading.Hencea verandahof1.5mandan overhangof0.75mis providedtoeffectivelyshade southside.Wintersunis allowedtoenter.

Northside:Verticalshading of25degcanbeeffective EastandWestsides :Both thesesidesaredifficultto shade.

Temperaturerange

Monthlydiurnalaverages

Windwheel

Thereisfrequentwinds fromthenorthwest.They arecoldinwinterandhot insummer.Southeasterly dampwindsspringup betweenJulyandOctober. Hotanddrysouthwinds prevailinspringandearly summer.TheShamal,a northwesterlywind commonduringJuneand July,causesdramatic sandstorms.

Generalfeatures

Kuwait,hasadesertclimate,with mildwintersandveryhotsummers. Thesunusuallyshinesallyear round.ThewinterseasoninKuwait iscolderthanothercoastalcountries intheArabianPeninsula.Summers inKuwaitaresomeofthehotteston earth.Kuwaitisalsolesshumidthan othercoastalregionsintheArabian Peninsula

•Temperature

Summer

Day–40-50deg, Night–25-35deg,

Diurnalvariation–15-20deg (trytoreduce20-25deg)

Winter Day–5-25deg, Night–0-10deg (trytoincrease15deg)

•Cloudlesssky–highsolar radiation

•Strongsunlightreflectedfrom drylightcoloredground

•Lowhumidity25-40%

•Verylessprecipitation<500 mm/yr

•Frequentduststorm.

OrientationandLayout

Enclosed,Compactplan toReduceperimeterto arearatio.

NonHabitableroom (Toilet)placedas thermal barriers,inwestside.

Windowsavoided on westfacade.

Tiltdown trellis asa protectionforwestfaçade.

Verandas –Inducesair movementdueto differentialheating

Deciduoustrees inthesouth toshadewallsandroofs. Plantedinawaynottoblock solarpanelsonroof.

Northsouthorientation ofmainfacades.

Openplan interiorassists crossventilation.

Vegetationandwindflow

North-SouthOrientationofmainfacadesSouthsidewindows

Shadingandopenings

Windowscompriseof 27%ofwallareafor adequate daylight.

Smallledgewalltoplace small indoorplant pots.

Alltheactivitieshavebeen alignedtothenorthside.

Tofacilitate cross-ventilation whendesired,windowsplaced onbothsidesoffacade

NonHabitableroom(Walkin Wardrobe)as thermalbarrier placedineastside

Windowsreduced oneast facadetoavoidheatgains.

Smalleastwindowtocapture easterlytradewinds.

Buildingfacing patioor courtyard

Glassandwindow properties–Verylowgvalue,Low-E,LowU-value

Westside windowsare dif�culttoshade. Hencewindowsare avoided.

Screens providedon windowsforprotection frominsects.

Southside windowsshaded by veranda of1.5mwidth and mashrabiya screens incorporatedtocut glare and radiation during summer.

Doublepaneclear glazingonsouthside.

Doublepanehigh performance(lowE)glazing onnorth

Northside vertical�nsof25ocan effectivelyshadethewindows(climate consultant).Louverstoletinair�ow,but blocktthwestsidesun.

Horizontalelongated windows-formoreday lightandeasytoshade.

Orientationforbreezes: exitopeningslargerthan entranceopenings

Northside Topof openingslevelwithceiling

Daytime -Absenceof openings/leastopenings/ smallopeningslocatedonwalls Night –Largeopeningstoemit heatout

Eastside windowsare dif�culttoshade.External shuttersused.Heavy shuttersmadeofwood (highthermalresistance).

Sliding Mashrabiya screens tocutlightduringday.

Plants/ivys tocutlightand dustfromeastandsouth.

Solarpanelsforenergy generationandactas shadingfortheroof Insulateddoublerooflayer

Containerwall

Framing

1”thickclosedcellrigidinsulation -notcontinuous-inbetween framesandcontainerwallsR6

2”thickclosedcellrigid insulation-continuousR13

Re�ectivemetalsidingtoprevent solarradiationfromenteringinside. Whitepaintedwalls

Recommendedinsulationvalue forlightweightconstruction wallsinKuwaitisR25andfor roofisR37

Lightcoloredwalls/ Re�ectivesurfaces/bright metalsurfacestoreduce heatgain.

Insulatedconstructionwith minimalin�ltration Externalandinternal Insulationtoreducedirect heatgain.

Allwallswellshaded.

Slopetowardssouthto

Framingtoholdboards andotherwiring.

2“Thickclosedcellspray foaminsulationR12

Waterbody inenclosedspace promotes evaporativecooling southeasterlywindsinthehot months.Italsoreduce dust givesvisualandpsychological relief.

Highlyre�ective/white paintedtimberwarmroof R9.7

Adequateslopetodrainthe rainwaterduringoccasional rains.

Projectingroofforshading ofthewalls

Naturallyventilatedroof space.

Finishcoat-White

Gypsumboard Radiantbarrier

2.5“Thickclosedcellspray foaminsulationR16

Mashrabiyascreenscanbekept openduring winter daytimesfor solargainthroughglazing. Use insulatedcurtains to trapheatduringwinter.

Insulate allthesidesofopening using�reresistantsprayfoam tominimizein�ltration.

Psychrometricchart

Allthewindowsare fullyoperable.No �xedpanes.

Externalshutters: Closedduring summerday, Openforventilationat summernight, Openon winterday forsolargain Closedon winternight toreduceheatloss. Shadingdevices Shouldbelowthermal capacitymaterials

Finishcoat

Gypsumboard

½“thickplywood

Containerroof

2“Thickclosedcellspray foaminsulationR12

Framing Framing

½“thickplywood

Gypsumboard

Finishcoat

Insulationtoreducedirect heatgain.

2stageevaporativecoolingbringsmaximumno.ofhours undercomfortconditions(42.1%).Sunshadingof windowscanbring22.9%ofhoursintocomfort.Internal heatgaincanbring23.3%ofhoursundercomfortduring wintermonths,whichshowstheneedofwellinsulated structure.Passivesolardirectgaincanalsocontributeto 10.8%.Directevaporativecoolingcanbring37.9%of hoursundercomfort.Thoughnotingreatpercentages, otherpassivestrategiesalsocontributestothecomfort conditions.Togethertheycancontributetothe comfortableindoorconditionsinagreatway

Solarenergy Othersystems

Floor-Sub�oorinsulated panels.

Hightemperatureandfrequentdusteffectsthe efficiencyofsolarpanels.Onanaverage,Standardpanel sizeof1.6x1mcanproduce1.58Kwh/dayconsidering theefficiencytobe11%.Onworstcastscenario efficiencycanevendropto7.5%.Thenthepanel produces1.08Kwh/day.Sofromthecontainer,roof(30 m2),itispossibletogenerateaminimumof19Kwh/day. Considering330daystoreceivesunlight6270kwh/year couldbegenerated

•2Stageevaporativecooling-Ductlesssystem recommendedtosaveceilingspace.

•Tanklesselectricwaterheaterforuseduring wintermonths.

•Fanforcedventilationduringdayandnightto flushheatout.

•Smartthermostatswithcontroloptions.

•Energyefficientappliancesandfixtures.

Northsidewindows

Southview

Northview

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HOTANDHUMID Location

Sunpathdiagramandshading

Southsidewindows

Thiruvananthapuram,India

Temperaturerange OrientationandLayout

Monthlydiurnalaverages

Thepredominantwind directionduringthe monsoonperiodie,from JunetoSeptember,iswest tosouth-west.Duringthe non-monsoonperiods,the predominantwind directionisfromnorth-east duringthemorningand westduringtheevening, whichshowsinfluenceof landbreeze.

Generalfeatures

•Temperature Summer Day–30-40deg, Night–25-30deg, Winter Day–25-30deg, Night–20-25deg

•Lessdiurnalvariation.No significantcoolingdownat night

•Heavycloud–overcastsky.Sky cover40-80%-cause

unpleasantglareRainfallis

highPrecipitation>1200mm/yr

•Highhumidity70-90%

•Radiationintensity–lessthanin hotdryclimate–diffused radiation–butsignificant sourceofheat

•Sticky

•Dampness

•Insectsandmosquitoesinlarge numbers.

Southside:Overhangof1.5m andverticalfinsinthewest sidecanbecomeaneffective shading.Henceaverandaof 1.5misprovidedtoeffectively shadesouthside.Theregion doesnothavedominant winterseasonandhencesolar gainduringwintermonthis notnecessary

Northside:Verticalshading of25degcanbeeffective EastandWestsides :Both thesesidesaredifficultto shade.

Shadingandopenings

Openplan withoutany obstructionstopromote Northsouthorientationwind�owatbodylevel. ofmainfacades.

Elongated,Narrowplan to assistcrossventilation.

Windowscompriseof40%ofwall areaforadequate daylight. Asper codeminimumrequirementis17%.

Smallledgewalltoplace small indoorplant pots.

Slidingfoldingdoorsonbothsides increasestheperimetertoarearatio–forlargerpossibilityofairmovement.

NonHabitableroom (Toilet)placedas thermal barriers,inwestside.

Tiltdown trellis asa protectionforwestfacade.

Windowsavoided onwest facade.

Verandas –Inducesair movementdueto differentialheating

Verandas –Onallsidesof habitableroomsforadequate shadingandairmovement.

Re�ectiveterracottaclaytile tore�ectsolarradiation, reducingfabricheatgains.

Terracottaclaytilehaslow thermalcapacity.Hencecools downeasily.

Rafters Rigidinsulation

Cement�berboardand�nish coat(belowinsulation).

Roofdesigntopromote stackventilation.Hence moreceilingheightin habitablespaces.

Sloppingrooftodrainrain waterandcutdownpartial solarradiation.

Floor-Sub�oorinsulatedpanels. Buildingonstilts–Forcooledearthand ventilationcoolingof�oor(alsotoprotect against�ooding)

Lightcoloredwalls/ Re�ectivesurfacesto reduceheatgain.

Insulatedconstructionwith minimalin�ltrationto preventlossofenergy whileairconditioned.

Wallsshouldbeshaded.

Finishcoat

Gypsumboard.

½“thickplywood

Singlerowofroomstoallow cross-ventilation

Buildingscanbeorientedto shadefromsunororientedto catchwhateverwind available.Ideallyinlowrise buildings,whenwallsdon’t getmuchradiation, orientationforwindis advisable.Containersurface beingmetal,haspossibilityof gettingoverheated.Hence orientationforavoidanceof sunhasbeenthedecisive factor.

Roomsaccessiblefromopen veranda.

Accordingtotraditionalclimatedesignprinciplesoftheregion(Vasthu),kitchenfacing eastsuchastoreceivethe�rstraysofsunisconsideredtobethebestpractice.

Westside windowsare dif�culttoshade. Hencewindowsareavoided.

Glassandwindow properties–Verylowgvalue,Low-E,LowU-value Screensprovidedonwindows forprotectionfrominsects andmosquitoes.

Southside windowsshadedby verandaof1.5mwidth.

Highceilinginlivingspacesand operablelouversonthetopfor hotairtoescape-Stackeffect.

Fullyopenablesliding foldingdoorstoletinwind fromsouth-westdirection.

Sizeofwindowopenings promoteair�owatbodylevel.

Northside vertical�nsof25oon westcaneffectivelyshadethe windows(climateconsultant).Here verandasprovideampleshading.

Northside Topofopeningslevel withceilingforthehotairtomove outandletinglarefreelight.

No�xedglass panes.Allwindows arefullyopenable.

Slidingfoldingdoors. Horizontalelongated windows-formoredaylight andeasytoshade

Eastside windowsare dif�culttoshade.Hence externaloperableshading devicesareusedinthe balcony.Givesprotection againstsunwhilelettingin breeze.Bamboocurtains hangingdownfromroofsare aneffectivesolution.

Openingsmadeaslargeas possibletomaximizeventilation.

Slopetowardssouthto favorsolarsolarpanels

Principleofthermalstorage cannotbeappliedinthis climate.Hencelightweight constructionofroofs.

Broadoverhangsfor shading

Solarpanelsforenergy generationandactas shadingfortheroof

Insulationtoreduceheat gain.

Wellinsulatedlowmass constructionpreferred.

Whitecolour�nishcoat aboveFibercementboard. PVC/compositedeckboard topreventsolarradiation fromhittingthewall.

Framing

Containerwall

Framingtoholdboardsand otherwiring

Vapourbarrier

ThickRigidinsulation

Asperclimateconsultant40%ofthehoursneedcooling

withthermalmasswithnightventilated,canmaintain workwell.Naturalventilationalongwithfanscanalso greatlycontributetocomfortconditionsinthisclimate.

Solarenergy Othersystems

Hightemperatureandovercastandskyduringmostof

recommendedtosaveceilingspace.

Northsidewindows

Shadingdevices-Shadingisoneofthedominant characteroftheregion.Shadingofallverticalsurfaces ensuredwithproperoverhangsandshadingdevices.

Fold-ablebamboocurtains onsouthsidetoreduce glareduringnoontime.

Insulateallthesidesof openingusing�reresistant sprayfoamtominimize in�ltration.

Vegetationandwindflow

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TEMPERATE Location

Sunpathdiagramandshading

Southside:Overhangof 80-90cmcanbecomean effectiveshadinginsummer whilelettinginwintersun.

Northside:Verticalshading of25degonthewestcanbe effective

Westside:Thissideis difficulttoshade.Dueto winddirection,windowsare essential.Windowsshaded withlouversarepreferred.

Bangalore,India

Temperaturerange OrientationandLayout

Orientation forbreezes andforsolarcontrol.The planhasbeendividedto2 zonestowelcomeallthe breezesfromeastand west.

Westwindow toletin windfromtheprevailing winddirection.

Northsouthorientation ofmainfacades.

Properventilationitself canbringmostofthe hoursundercomfortzone.

Openplan withoutany obstructionstopromote wind�owatbodylevel.

Monthlydiurnalaverages

Elongated,Narrowplan to assistcrossventilation.

Verandas –Inducesair movementdueto differentialheating

Windowscompriseof 20%ofwallareafor adequate daylight.

Southsidewindows

Shadingandopenings

Slidingfoldingdoorsonbothsides increasestheperimetertoarearatio–forlargerpossibilityofairmovement.

Theaveragehourlywind speedexperiences significantseasonal variationoverthecourseof theyear.Thewindismost oftenfromthewestfor almost5months,fromMay toOctober.Thewindis mostoftenfromtheeastfor almost6-7months,from OctobertoApril.Thereis alsosomewindfromsouth westduringsouthwest monsoonperiods.

Generalfeatures

Duetoitshighelevation,Bangalore usuallyenjoysamoremoderate climatethroughouttheyear, althoughoccasionalheatwavescan makesummersomewhat uncomfortable.Thehotseasonlasts for2.5monthswithanaveragedaily hightemperatureabove32°C.The hottestmonthoftheyearin BengaluruisApril,withanaverage highof34°Candlowof22°C.The coolseasonlastsfor3.3months,from SeptembertoJanuary,withan averagedailyhightemperature

below28°C.Thecoldestmonthof theyearinBengaluruisDecember, withanaveragelowof17°Candhigh of27°C..Bangalorereceivesrainfall fromboththenortheastandthe southwestmonsoons.Humidityis highduringrainyseason.Bengaluru experiencesextremeseasonal variationintheperceived humidity.Themuggierperiodofthe yearlastsfor8.0months,fromApril toDecember,duringwhichtimethe comfortlevelismuggy,oppressive, ormiserableatleast22%ofthetime

Roomsaccessible fromopenveranda.

Roof,Walls,Floor

Finishcoat

Cement�berboard

½“thickplywood

Insofastinsulation-designed forthecorrugationsof containerwalls.Consistsof gapstoaccommodatewiring andotherplumbingworks.

Containerwall

Re�ectivelightcolored paintsontheexposed containerwalls.

Lightcoloredwalls/ Re�ectivesurfacesto reduceheatgain.

Regionexperiences moderatetemperate climate.Henceexternal surfacesarenotinsulated.

Internalinsulationand propershadingofwalls.

Wellinsulatedlowmass constructionpreferred.

Floor-Finish

Floor-Sub�oorinsulatedpanels.

Eastside:Withadequate shading,eastsidewindows canbedesignedonlytoletin comfortableearlymorning sunrays.

Singlerowofroomstoallow cross-ventilation Winddirectionduringwinter seasonisfromeast.Hence planttreestoblockwind.

Westside windowswith louverstocutsolarradiation whilelettinginbreeze.

Buildingscanbeorientedto shadefromsunororientedto catchwhateverwind available.Ideallyinlowrise buildings,whenwallsdon’t getmuchradiation, orientationforwindis advisable.Containersurface beingmetal,haspossibilityof gettingoverheated.Hence orientationforavoidanceof sunhasbeenthedecisive factor.

Glassandwindow properties–Low-E,Low U-value Screensprovidedonwindows forprotectionfrominsects andmosquitoes.

Southside windowsshadedby veranda.

Openingsmadeaslargeas possibletomaximizeventilation.

Fullyopenableslidingfolding doorstoletinwindandincrease perimetertoarearatiowhile open.

Sizeofwindowopenings promoteair�owatbodylevel.

Northside Clearstoreyopenings withoperablewidowsforthehotairto moveoutandletinglarefreelight.

Northside vertical�nsof 25oonwestandeastcan effectivelyshadethe windows(climateconsultant).

No�xedglasspanes. Allwindowsarefully openable.

Slidingfoldingdoors.

Southsideglasswithhighgvalue(withsummershading)for internalheatgaininwinter.

Verandashades East side windows-from summersunwhile lettinginwintersun.

Insulateallthesidesofopening using�reresistantsprayfoamto minimizein�ltration.

Re�ectiveterracottaclay tiletore�ectsolar radiation,reducingfabric heatgains.

Terracottaclaytilehaslow thermalcapacity.Hence coolsdowneasily.

Rafters

Rockwoolsandwichpanels insultation.

Cement�berboard

Woodenpanelingonceiling

Highceilings.

Roofdesigntopromote stackventilationandletin morenorthernlight.

Sloppingrooftodrainrain waterandcutdownpartial solarradiation.

Slopetowardssouthto favorsolarsolarpanels

Broadoverhangsfor shading Solarpanelsforenergy generationandactas shadingfortheroof

Insulationtoreduceheat gain.

Mostofthehighhumidhourslieswithinthecomfort temperaturesitself.Hence,justdehumidificationitself canbring46.8%ofhoursundercomfort.Withpassive designstrategiesitselfwecanalmostbringmorethan 80%ofhoursundercomfortconditions.Sunshadingof windowscancontributeto28.9%.Thermalmassand thermalmasswithnocturnalventilationcantogether contributeto8.9%ofhours.Naturalandfanforced ventilationcantogetherbringanother7.8%ofhours undercontrol.Regionexperiencesmildwiinterand henceinternalheatgainandpassivesolargaincanbring 22.3%ofhoursundercomfort.

Solarenergy

Solarpanelworkbestinmodrateclimates.However, overcastskyduringsomeofthemonthscaneffectthe efficiencyofsolarpanels.Theefficiencyinthisregionis around17%.Onanaverage,Standardpanelsizeof1.6x1 mcanproduce1.9Kwh/dayconsideringtheefficiencyto be17%.Sofromthecontainer,roof(30m2),itispossible togenerateaminimumof29Kwh/day.Considering300 daystoreceivesunlight,approximately9200kwh/year couldbegenerated.

Groundtemperaturesarealmostlimitedwithinthe comfortrange.So, Earthairtunnel canbeagood strategyforthisclimate.Evenatadepthof0.5mthe temperaturesarereallystable.Soevenwitharelatively smallerdepth,earthairtunnelscanbesuccessful.

•2Stageevaporativecooling-Ductlesssystem recommendedtosaveceilingspace.

•Solarwaterheaters.

•Fanforcedventilation

•Rainwaterharvestingsystem.

•Dehumidification-thisonlycanbring46.8%of hoursundercomfort.

Horizontalelongated windows-formore daylightandeasyto shade

Northsidewindows

Accordingtotraditionalclimatedesignprinciplesoftheregion(Vasthu),kitchenfacing

Useinsulatedinternalcurtains totrapheatduringwinter.

N E

W S

North-SouthOrientationofmainfacades Windflow

DISSERTATION-SUMMARY

WINDOWSINTHECLIMATEOFTHEUK

INTRODUCTION

BACKGROUND

Recently,human-inducedclimatechangehashadobservableeffectsonthe environment.Expertsbelievethatiftheglobaltemperaturesarenotlimited wellbelow2°Cabovepre-industriallevels,wewillhavetofacesevere consequencesofclimatechange.Asper"TheParisAgreement",theUKis committedtoreachingnet-zeroenergyby2050.IntheUK,the constructionindustryisresponsiblefor49%ofcarbonemissions;hence,it isnecessarytotakequickactionstodecarbonizethissector.

Toachievenet-zeroby2050,theUKisattemptingtoproducealarge percentageofenergyfromrenewablesourceswhilesimultaneously improvingtheenergyperformanceofallexistingandnewbuildingsto lowerthedemandsofthenewdecarbonizedgrid.Therefore,reducingthe energydemandsofbuildingsisofgreatimportance.Newtechnologiesare developedandintroducedtoimprovebuildingenergyconsumption. Validatingtheperformanceofthesetechnologiesindiverseenvironments isimperative.Onlythencantheactualenergy-savingpotentialofthese technologiesbeunderstood.Therefore,assessingthesetechnologies' performanceintheearlystagesiscrucial.

Electrochromic(EC)windowglazingisonesuchtechnologythatcan dynamicallycontroltheentryofdaylightandsolarradiationintobuildings. Thistechnologyissaidtohelpachieveenergyefficiencybylettinginand shieldingthesundynamicallyinreactiontoclimaticandweather conditions,reducingtheenergyconsumedforheating,cooling,and lighting. Theelectrochromicwindowswereintroducedinthemarketasan alternativetothetraditionalwindowsthatrequireshadingdevices.Itisan electronicallytintableglassthatcandynamicallycontrolglarefromdirect sunorbrightskywhilemaintainingoccupantcomfort,maximizingaccess todaylightandoutdoorviews,reducingenergycosts,andproviding architectswithmoredesignfreedom.Thesewindowsaremorepopularfor theirenergy-savingpotential.Electrochromic(EC)devicesconsistof materialsthatcanchangetheirpropertieswhenelectriccurrentorvoltage isapplied.

Electrochromicwindowsconsistofuniquematerialsthathave ‘electrochromic’properties.Amaterialthatchangescolorwhenenergized byelectricityiscalled"electrochromic".Inthesematerials,electricity initiatesachemicalreaction.Thischemicalreactionchangestheproperties ofthematerial.Thematerialcanbechangedbetweencoloredand transparentstatesinelectrochromicwindowsbyapplyingelectricity. Differentlevelsofvisibilityareavailablewithelectrochromicwindows,just likesuspendedparticledevices

Whystudyonofficebuildings?

Largewindowsandunobstructedexteriorviewsareessentialinanoffice buildingtoensurethehealthandwell-beingoftheemployees.Itis thereforecommonforofficebuildingstohavelargerwindows.Thisalso becomesoneofthereasonswhyofficesarefoundinbuildingswithlarge, glazedfacades.Officeshavebecomeoneofthemostoccupiedtypologiesin mosthigh-risebuildingsinurbancenters.Duetoseveraladvantages,glazed facadesarebecomingthedesigner'sfavoriteforhigh-risebuildingsand skyscrapers.However,astheglazingareaincreases,theyfacilitateheat transferbetweentheinteriorandexterior,whichincreasesthecoolingand heatingloads.

Therefore,inthesetypesofbuildings,thechoiceofglazingtypebecomes extremelyimportant.Hence,officebuildingsbecomeoneofthemost appropriatechoicesoftypologyforthisstudy.

WhyLondonandManchester?

SageGlassbySaint-Gobainisoneoftheworld'sleadingmanufacturersof electrochromicwindows.ThepropertiesofSageGlasselectrochromic windowshavebeenusedinthisstudytoperformsimulation. ElectrochromiccoatingofSageGlassconsistsoffivelayersofceramic material,whicharelessthan1/50ththethicknessofahumanhair.

WhytheUK?

StudieshaveshownthatECwindowsaremoreeffectiveinwarmer climatesasithelpsindynamicsolarcontrol,therebyreducingthecooling loadsdrastically.Electrochromic(EC)windowshavebeenstudied extensivelyfortheirenergyperformance,butahandfularedonefor cooling-dominatedlocations.Researchonheating-dominatedregionsis minimal.Therehasbeenverylittlestudyofthesewindows'impactinthe UKsinceitispredominantlyaheating-dominatedregion.

However,theUKhasbeenwarmerduetoclimatechangeoverthepastfew years.Futureclimatepredictionsshowthatwinterswillbewarmer,and summerswillbehotteranddrier.Currently,thesummersaremuchhotter intheUKthaninpastdecades,andmanybuildingsinthecitiesface overheatingissuesinthesummer.Inaddition,manyofficebuildingsare saidtorequiremechanicalcoolinginthefuture.Therefore,assessingthe performanceofECwindowsinthisclimateishighlyrelevantasitmight becomeanexcellentsolutiontoreducethecoolingloadsorsometimes altogetheravoidairconditioningthatmightbeneededinthefuture.

Accordingtothelistofthe mostpopulatedurban areasintheUnited Kingdom,asdefinedby theOfficeforNational Statistics(ONS),London andManchesterarethe largestandthesecondlargesturbanareasinthe UK.Therefore,boththese locationshavemanyoffice buildings.Thisbecomes oneofthereasonsforthe choiceoflocation.The mostcrucialfactoristhe differencesintheclimate ofbothlocations.London fallsinthesouthernpartof theUKandexperiencesa warmerclimatethanother regionsintheUK.In addition,thecityhasan urbanheatislandeffect.Ontheotherhand,Manchesterliesinthecentral portionoftheUKandhasadifferentclimatethanLondon.Adetailed climaticcomparisonofbothlocationscanbefoundinthenextsection; henceLondonandManchesterhavebeenchosenasthelocationsofstudy. Ideally,otherlocationsinhigherlatitudesshouldalsobeconsideredinthe studytogetacompletepictureoftheperformanceofECwindowsinthe UK.However,consideringthestudy'stimeframe,scopeandextent,the numberoflocationshasbeenlimitedtotwo.

RESEARCHAIMS,OBJECTIVESANDHYPOTHESIS

ResearchAimsandObjectives

ThisresearchaimsatevaluatingtheannualenergyperformanceofofficebuildingswithECwindowsintheclimate oftheUK.TheenergyperformanceofECwindowswillbecomparedwithclear,LoEArgon-filleddoubleandtripleglazedunits.Thestudywillfocusontheeffectofvariousdesignparametersandeachcase'stotal,heating,cooling, andlightingenergyconsumption.Theevaluationswillbedoneforbothcurrentandfutureweatherfilestoassess thelong-termeffect.

TheUKisinacoldtemperatezone,andveryfewstudieshavebeenconductedontheeffectofelectrochromic windows.So,themainquestionsthisresearchaimstoanswerare:

� AreECwindowseffectiveinreducingenergyconsumptionintheclimateoftheUK?

� Inwhichlocation(London/Manchester)dothesewindowsperformbetter,andwhataretheenergy-saving potentials?

� Inwhichorientationsdothesewindowsperformbest?

� Inwhichwindow-to-wallarearatiosdothesewindowsperformbest?

� Whichisthemostinfluentialdesignparameter?

� Comparedtothebasescenario,howmuchdothesewindowsreduceorincreaseenergyconsumption?

Theactualperformanceofanysystemisnotlimitedtothefactorsdiscussedaboveandisdependentonseveralother localfactors.Henceacompletedecisioncannotbemadebasedonthisstudy.However,thisresearchcanactasan initialreferenceforenergyassessorsandsustainablearchitectsbeforeconsideringelectrochromicwindowsin buildings.

Hypothesis

Thehypothesiswasthat,comparedtobasescenarios,

� ECwindowseffectivelyreducetotalannualenergyconsumptionintheclimateoftheUK.

� DuetoLondon'shighertemperaturesthanManchester,ECwindowssavemoreenergyinLondon.

� EnergysavingsofECwindowsaremoreinsouthernorientations.

� ECwindowshelpinreducingcoolingenergy.

� ECwindowsmakesignificantsavingsinlightingenergy.

ResearchGaps

Followingaretheidentifiedgapsintheresearch:

� ItwasfoundthatseveralstudieshavebeendoneonECwindows,andtheirenergy-savingpotentialshave beencalculated,butmostofthemweredoneincooling-dominatedregions.

� Veryfewstudieshavebeendoneinheating-dominatedregions.Forexample,theUKisaheatingdominatedregion,andveryfewresearchershavetriedtoevaluatetheECwindow'seffectivenessinthisclimate.

� NoneofthestudiesdoneintheUKcontexthasdeeplyanalyzedECwindows'totalenergysaving potential.

� Theparametersconsideredinthestudiesarealsoless.Forexample,inthecaseofWWRandorientations, manyresearchpapersreferredhighlightedtheimportanceoftheseparameters.However,thestudieshave consideredonlyoneorthreeWWRsinspecificorientations,whichmaynotgiveacompletepictureofthe performanceofECwindows.OnlyadetailedanalysisofdifferentWWRsandorientationscangiveacomplete pictureoftheeffectivenessofthesewindows.

� ItwasalsoobservedthatmostoftheresearchpapershadcomparedtheperformanceofECwindowswith singlepanewindows.Thiswillshowalargerpercentageofenergysaving.Inarealscenario,designersneedto knowhowfartheyperformbetterthanefficientstandarddouble-glazedortriple-glazedunitsavailableinthe market.

� Thestudiesthatusedsensitivityanalysistoidentifythemostinfluentialdesignparameterhaveconsidered overallbuildingconstructionparameters.Windowparametersjustbecomesomeamongthem.Nostudieshave doneasensitivityanalysisexclusivelyforwindowdesignparametersandstudieditsrelativeimportance.

Mostoftheresearchpapersreferredhadsimilaraimstotheresearchquestionsofthisstudy.Thedifferenceliesin thelocation,climateandtheparametersconsidered.Thisstudyaimstobridgethisgapandcontributetothe knowledgeabouttheperformanceofECwindowsintheclimateoftheUK,whichcanbecomeavaluablereference duringtheearlystagesofthedesign.

METHODOLOGY

LOCATIONS

LondonandManchesterarethetwolocationschosenforthisresearch. Diversityintheirclimatesisoneofthereasonsforthechoiceofthesetwo locations.Asperthe4.5SRESscenario,thecurrentandfutureweatherfiles ofbothlocationsarecomparedandshowninthefollowingfigures.Values fromthe.epwfilesofthelocationsgeneratedusingMeteonormsoftware areusedtocreatethegraphsbelow. TemperaturegraphsclearlyshowthatLondoniswarmerthanManchester. Asperthetemperaturerecordsof2022,thetemperatureinLondonhas goneashighas40degrees.However,futureweatherfilesalsoshowthatthe temperatureswillrise.

RelativeHumidity

GraphsshowthatManchesterismorehumidthanLondon.Inthefuture, forsummermonths,humidityslightlyreducesby2050andthenagain increaseby2080.

Temperature

Wind

Thepredominantwinddirectionsinbothlocationsremainthesamein currentandfutureclimates.Manchesterexperiencescoolerandstronger winds.InLondon,thewinddirectionismainlyfromthewestand southwest;inManchester,thewinddirectionispredominantlysouthwest. Thereisnosignificantchangeinwindspeedinfutureweatherconditions. ManchesterexperiencesstrongerwindsthanLondononanaveragedaily basis.However,onobservingthegraphofrecordedhighandlowwind speeds,itcanbeobservedthattherecordedhighwindspeedsinLondon arehigher.

London

METHODOLOGY

LOCATIONS

ThesunshadingchartofLondonsignifiesthenecessityofshadingdevicesforcurrentclimates,whereasin Manchester,thoughshadingmaynotbesignificantinthecurrentscenario,itcanhaveaconsiderableeffectinfuture climates.Thegraphsalsoshowthatconsiderablydeepoverhangscanonlyeffectivelycontrolthesummersunin London.

London

PsychrometricchartManchester

InLondon,theregularcomforthoursrisefrom12.6%inthecurrentclimateto15%in2080.Asthetemperaturerises, morehoursbelowthecomfortzonefallintothecomfortzone.Theeffectivenessofwindowshadingalsoincreases. Theheatingloaddecreasesby2050andrisesby2080,whereasthecoolingloadincreasesby2050andslightly reduceby2080.Theeffectivenessofpassivetechniqueslikedirectevaporativecooling,naturalventilation,fanforcedventilation,etc.,areslightlyreducingovertheyears.Internalheatagainandheatingplayasignificantrolein bringingcomfortableconditions.Passivesolarheatgainsalsohelpinbringingmanyhoursintocomfortable conditions.ThoughECwindowsinclearstatehelpinpassivesolarheatgain,itispossiblethatECwindows performwellintermsofenergysavingsintheseclimates.

InManchester,thepercentageofregularcomforthoursrisesfrom5.6%inthecurrentclimateto6.9%in2080.In London,heatingcouldbring38%ofhoursintothecomfortzone,whereasinManchester,heatingisrequiredto bring49.2%ofhoursintocomfortconditions.Thisshowsthedifferenceintemperaturesinbothlocations.The heatingloadreducesovertheyears;however,inthisregion,coolingisrequiredforafewhoursinthefuture,though itisnotrequiredinthecurrentcondition.

Allthegraphsanalyzedsofarshowthedifferencesintheclimaticconditionsofbothlocations.Inaddition,the temperature,relativehumidity,sunshading,psychrometricchartsandfutureclimaticconditionsshowthatthe temperaturesarerisingandwillcontinuetorise,whichmakestheevaluationofenergy-savingtechnologieslike Electrochromicwindowshighlysignificant.Inaddition,performanceevaluationofECwindowsintheseclimates cangiveapictureofhowfartheyareeffectiveintheclimateoftheUK.

METHODOLOGY

BUILDINGMODELANDPARAMETERSSTUDIED

BuildingModel Parametersstudied

BuildingGeometry

Asquareshaped,six-sidedrepresentativeofficebuildingoflength12m,width12mandheight3mwasmodelledin designbuilder.Oneofthefaçadesconsistedofawindow.Theglazingtemplates,window-to-wallarearatiosand orientationsofthiswindowwerevariedduringsimulations.Asaruleofthumb,daylightpenetratesaroomformost latitudes,roughly2.5timestheheightofthetopofthewindow (IbrahimandHayman2005).Thestandardheight ofthetestcellwas3m.Thedaylightzonemayvaryslightlyfordifferentorientations.Hence,toensurethattheeffect ofnaturaldaylightandartificiallightisquantifiedcorrectly,4timesthewindow'sheight(12m)waschosenasthe dimensionofthesidesoftheroom.Asquareshapewaschosentoensurethatthegains/lossesremainedidentical fromallsides

BuildingConstruction

Defaultstate-of-the-artmedium-weightconstructiontemplatesavailableinDesignBuilderwereusedfortheroof, walls,andgroundfloor.TheU-valuesweremodifiedto0.1W/m2-K.TheLETIstandardhasbeenfollowedhere. LETIsuggestsaU-valuebetween0.13-0.15W/m2-Kforwalls,0.08-0.10W/m2-Kforfloor,and0.10-0.12W/m2-K forRoof.Table1showsthetestcell’sfabricU-values.AspertheLETIstandard,theairtightnessneedstobeless than1m3/h-m2@50Pa.However,thistestcellhasbeenmadeairtightasperthePassivhausstandard(<0.6m3/h-m2 a@50Pa).

Fourmajorparameterswerestudiedandanalyzedinthisresearch.

Location Glazingtype

TounderstandtheeffectoflocationontheperformanceofElectrochromicwindows,2locationswerechosenforthe study.Consideringthetimeframeandextensivenumberofsimulationsinvolvedinthisstudy,thenumberof locationschosenwaslimitedto2.Inadditiontocurrentweatherfiles,futureweatherfilesfor2050and2080asper 4.5SRESscenariowasalsoobtainedforbothlocationsandusedinthesimulations.

Detaileddescriptionsofalltheglazingtypesusedinthestudyaredescribedinthefollowingsections.Thestudy aimstoanalyzeifelectrochromicwindowsareeffectiveintheUKclimateandcomparetheirperformancewith standarddoubleandtriple-glazedunits.So,thebasecaseisaclearLoEArgon-filledglazingtype.Inareal-life scenario,theglazingunitsmayhaveinternalshadingdevicestocontrolexcessiveheatandlightfromthesun.The energyperformanceofthetransparentstatewindowswilldifferfromthosewithinternalblinds.Hence,EC windowsarealsocomparedwithclearLoEArgon-filledwindowswithinternalblinds.

WindowtoWallareaRatio(WWR)

Oneofthevariablesconsideredwasthewindow-to-wallarearatio.Thoughseveralstudieshaveemphasizedthe importanceofWWR,veryfewstudieshaveobservedtheenergyconsumptionofECwindowsindifferentWWRs. So,thisresearchtriedtoanalyzehowtheenergyconsumptionchangesforeachglazingtypefordifferentWWRs. Thechoiceof10ratiosinequalintervalshelpsidentifyhowenergyvariesastheratiosgraduallyincrease.

Orientation

Simulationresultswereobtainedforallmajor8orientations.ThishelpsidentifytheorientationwhereECwindows aremosteffectiveandleasteffective.

METHODOLOGY

SOFTWAREANDSIMULATIONS

Inthisstudy,thecurrentandfutureweatherfilesforthelocationswereobtainedfromMeteonormsoftware.Energy plusweatherdatafiles(.epw)wereusedforsimulations.SimulationsweredoneusingtheDesignBuildersoftware. DesignBuildersoftwarelibrarieshaveseveraloptionsforElectrochromicwindowconfigurations.Thetemplatesfor SageGlassElectrochromicwindows,mainlyusedinthisstudy,areavailableinDesignBuilder.Moreover,Design BuilderalsohasthefeatureofperformingSensitivityanalysis.Thedesignbuilder'sabilitytomodelandconfigure Electrochromicwindowsandperformsensitivityanalysismakesitanidealchoiceforthisstudy.

2240simulationswereperformedforLondonandManchestertostudytheenergyperformanceofdifferentglazing templatesinvariousorientationsandWWRs.Inaddition,20000Simulationrunsweremadeforsensitivityanalysis tofindthemostinfluentialonesamongtheparametersanalyzed.

DifferentsettingsdoneinDesignBuilderforperformingsimulationsareexplainedinthesectionsbelow.

Activity

ThesimulationsusedagenericopenofficeactivitytemplateinDesignbuilderanddefaultsettings.Computers, officeequipmentandothermiscellaneousequipment,wereconsideredONinthiszone.

Lighting

RecessedLEDlightswithlinearcontrolwereusedinsidethetestcell.Targetilluminancewas400lux.Other settingsareshowninthetable5.Exteriorlightingwasturnedon;however,onlytheinternallightingenergywas consideredforthestudyonlightingenergy.Exteriorlightingwascontrolledasperthescheduleandwasconsidered offinthedaytime.

HVAC

Thesimulationsusedanair-to-waterheatpump(ASHP)templatewithconvectorsandnaturalventilation.Default settingswerenotamended.Mechanicalventilation,heatrecovery,heating,cooling,domestichotwater,andnatural ventilationwereturnedON.

Openings

AsthestudyinvolvestheperformanceevaluationofECwindows,6glazingtypeswereused.Theperformanceof double-glazedandtriple-glazedECwindowswascomparedwithstandarddoubleandtriple-glazedclearunits withlowEvalueandargonfilling.Separatetemplateswithandwithoutinternalblindswerecreatedforclear,LowE,Argon-filledunitstoquantifytheenergydifference.Thetemplatesusedforthestudyareshowninthetable below.WWRswerevariedduringthesimulations.

ClearLoEArgonfilled(Basecase1)

Propertiesoftheglazingtypeareshownbelow.

ClearLoEArgonfilled,withinternalblinds(Basecase2)

Alltheglazingdataremainsthesameasabove;however,internalblindswereaddedtodoubleandtriple-glazed units.Inaddition,outsideairtemperatureandhorizontalsolarcontroltypeisusedtoreducezoneheatingand coolingloads.ShadingisoniftheoutsideairtemperatureexceedstheOutsideairtemperaturesetpoint andifthe horizontalsolarradiationonthewindowexceedsthesolarsetpoint.

METHODOLOGY

Electrochromicglazing

TwoSageGlassElectrochromicglazingconfigurations,double-glazedandtriple-glazed,werecreatedinDesign Builder.Bydefault,someSageGlassdoubleandtriple-glazingunitsarealreadydefinedintheDesignBuilderglazing library.Thepropertiesofthechosentemplatesareshownbelow.

Defaultshadingsystemsdefinedinthesoftwarewereusedforthesimulations.However,eachprojectmayadjust andadaptthesevaluestoachieveoptimumperformanceresults.

Theoperationscheduleshownintheactivitysectionwaschosenforthesimulations.Whentheschedulehasavalue of0,tintingcannotoccur,regardlessofanyglareortemperature.Hence‘Heating/coolingoverrideonlyoperated outsideoperationschedule’optionwasturnedON.Thecontroloptionselectedwas‘Fulltintingwhencoolingand notintingwhenheating’.Asperthisoption,whileheatingenergyisdeliveredtothespace,theglazingremainsclear, andwhencoolingisrequired,itbecomesfullytinted.Otherwise,tintingisdeterminedbyincidentsolaras describedbasedondaylightingrequirements.

Inthisstudy,energyperformanceofelectrochromicwindowsisevaluated.Hence,the‘Controlpriority’modeis ‘Energy’.Thepresenceofheatingandcoolingischeckedforbeforethepresenceofglare.Energysavingisprioritized ratherthanglarecontrol.Propertiesofthevarioussetpointsintheshadingtemplatechosenaresummarizedinthe tablebelow

Appropriateshadingsystemswerealsochosen.Bydefault,somewindowshadingoptionsarealsodefinedinthe Design-Builderwindowshadinglibrary.SageGlassClassicSR2.0templatewaschosen,anddetailsareshown below.

METHODOLOGY

SENSITIVITYANALYSIS

Amongalltheparametersdiscussed,itisnecessarytoidentifythemostcriticalones.Hence,sensitivityanalysiswas performedtoidentifythemostinfluentialdesignparameteramongtheparametersanalyzed.Theparameters studiedandthemeasuredoutputsforsensitivityanalysisareshownintablebelow.

Thedistributioncurvesofthedesignparametersareshowninthefollowingfigures.InDesignBuilder,Uncertainty andSensitivityAnalysisaredonesimultaneously.Inthisstudy,theprimaryaimistodosensitivityanalysistofind eachdesignparameter'shierarchyofinfluenceratherthanuncertainty.Hence,eachdesignvariablewasconsidered equalprobability,soallvariableshaveuniformdistributioncurves.LHSsamplingmethodisusedforsettingupthis analysis.Latinhypercubesamplingisahighlyefficientsamplingmethod.Asaruleofthumb,asamplesizeof10 timesthenumberofdesignvariableswillbesufficientforthepopulationmeantobeaccuratelymodeled.So,almost 240simulationswillbeenoughtogetreliableresults.However,toincreaseconfidenceandreliability,asamplesize of2000wasrequestedineachanalysis.Separatesensitivityanalysissimulationsweredonetomeasureeachoutput.

Theregressionsensitivitymethodisusedforthisanalysis.Regressionanalysis(multiplelinearregression)isa statisticalmethodthatestimatestherelationshipsamonginputvariables.Regressionanalysishelpstounderstand howtheoutput'stypicalvaluechangeswheninputvariablesarevaried(assumingthattheinputvariablesare independentofeachother).

RESULTS

ENERGYCOMPARISON-LONDONANDMANCHESTER

2240simulationswereperformed,andthetotal,heating,cooling,andinternallightingenergieswereobtained.The resultswereanalyzedbasedon4majorparameters:Location,glazingtemplates,orientation,andwindow-to-wall arearatio.Inaddition,asensitivityanalysiswasdonewiththese4parameters.20000simulationrunswere performedforsensitivityanalysis.

Doubleglazed-Totalenergy

ItcanbeobservedfromthechartsthattheenergyconsumptioninLondonishigherthanthatofManchester.For standardclearLoEArgonfilleddoubleglazedunits(Basecase),thisdifferenceinenergyvariesbetween5.4%to 9.7%,andfordoubleglazedECwindows,itvariesbetween8.4%to9.7%.TherangeofvariationislesswhenEC windowsareused.Forbasecaseunits,thevariationishighestinthesouthandlowestinthenorth.

Inthissection,thedifferencebetweentheenergyrequirementsofLondonandManchesterarecompared.Total, heating,cooling,andlightingenergiesofdouble-glazedandtriple-glazedunitsarecompared,andthedifferenceis quantified.Thishelpsidentifyhowfarthedifferencesintheclimatesofbothlocationsimpacttheenergy consumptionandwhichonesconsumesmore/lesstotal,heating,cooling,andlightingenergies.

Doubleglazed-Heatingenergy

ThoughthetotalenergyconsumedbythetestcellinLondonismorethanthatofManchester,furthercalculations havebeendone,consideringLondonhasahighervalue.Hencenegativevaluesindicatethattheenergyrequirement ofManchesterishigherthanthatofLondonandpositivevaluesindicatethattheenergyconsumptionofLondonis higher.Onlygraphsofnorthandsouthareshown.

RESULTS

ENERGYCOMPARISON-LONDONANDMANCHESTER

Doubleglazed-Coolingenergy

ThecoolingenergydemandofLondonismorethanthatofManchester.Whenbasecaseunitsareused,London consumes8.5%-27.4%moreenergyforcooling.WhenECglazingisused,theenergydifferencebetweenboth locationsvariesbetween22%and27%.Therangeofdifferenceinenergyishighestforbasecaseunits.Innorth, thereisnosignificantenergydifferencebetweentheglazingtypes.However,inthesouth,thevariationinthe energydifferenceissignificantwhenbasecaseunitsareused.AstheWWRincreases,theenergydifference betweenbothlocationsreduces,andwhenitreaches100%,thereisnosignificantenergydifferenceincooling betweenLondonandManchester.WhenECwindowsareused,theenergydifferencebetweenbothlocationsdoes notvarysignificantly.

Doubleglazed-Lightingenergy

Asdiscussedintheprevioussection,negativevaluesindicatethattheenergyrequirementofManchesterishigher thanthatofLondonandpositivevaluesindicatethattheenergyconsumptionofLondonishigher.

Asageneraltrend,thelightingenergyconsumptionofthetestcellinLondonisupto4.2%morethanthatof Manchester.However,thereareafewexceptions.Forbasecaseunits,inwest,northwest,northandnortheast orientations,forfewwindowstowallarearatios,theconsumptioninManchesterisslightlyhigherthaninLondon. WhenECwindowsareused,exceptfewvariationsinsouthandsouthwestorientations,theenergyconsumption inLondonismorethanthatofManchester.

ENERGYCOMPARISON-LONDONANDMANCHESTER

Trippleglazed-Totalenergy

London - North - DG

London - North - TG

Triple-glazedunitsalsoshowasimilartrendasdouble-glazedunits.TheenergyconsumptioninLondonismore thaninManchester.Thepercentageofdifferencesinenergiesisalsosimilartodouble-glazedunits. TheheatingenergydemandinManchesterishigherthanthatofLondon;however,thereareexceptionsinsouthand southwestorientations.Inbothorientations,forbasecaseunits,forhigherWWRs,theenergydemandinLondon isslightlyhigherthanthatofManchester.Thisreversetrenddoesnotoccurwhendouble-glazedECunitsareused. Forbasecaseunits,theheatingenergyofManchesteris0-20.4%morethanLondonexceptinsouthandsouthwest orientations.WhenECtriple-glazedunitsareused,Manchesterneeds2.3%-17.68%moreenergythanLondonfor heating.TherangeofenergydifferencebetweenbothlocationsislesserforECwindows.

Trippleglazed-Heatingenergy

London East DG

Trippleglazed-Coolingenergy

ThecoolingenergydemandinLondonishigherthaninManchester,andthereareonlyslightdifferencesinthe percentagesofenergydifferencewhencomparedtodouble-glazedunits.Whenclearbasecaseunitsareused, Londonconsumes8.5%-25.9%moreenergyforcooling.Whentriple-glazedECunitsareused,theenergy differencebetweenbothlocationsvariesbetween21.5%and25.5%.Thetrendofenergygraphsremainsthesameas thatofdouble-glazedunits.

Trippleglazed-Lightingenergy

London East TG

London South DG

London - South - TG

Exceptforafewvariationsinwest,northwest,northandnortheastdirections,forbasecaseunits,theenergy consumptionofLondonismorethanthatofManchesterevenwhentriple-glazedunitsareused. Fromallthegraphsofdouble-glazedandtriple-glazedunits,itcanbesummarizedthatthetotalenergy consumptionofLondonismorethanthatofManchester.Whensplittingupoftheenergyisobserved,Manchester consumesmoreenergythanLondonforheating,whereasLondon'scoolingandlightingenergydemandsaregreater exceptinafeworientationsandwindow-to-wallarearatios.TherangeofdifferencesishigherforclearLoEargonfilledunitsthanforelectrochromicunits.

Summary

London West DG

Energyincreaseinfuture

InLondonandManchester,energyuseisexpectedtorisebyupto6%and5%,respectively,inthecomingyears.The increaseofenergyislessinLondonwhenECwindowsareused.However,inManchester,anoppositetrendis observed.Theprobablereasonisthat,asthetemperatureincreases,therearemorecoolingenergysavingsin London,whereasinManchester,asthetemperatureincreases,toavoidglare,theelectrochromicwindowsgoto tintedmodemorethanthecurrentclimate,whichcanleadtoincreaseinlightingenergydemandthanatpresent.

RESULTS

EFFECTOFLOCATIONONENERGY

TheprevioussectionpresentedindetailthedifferenceinenergybetweenLondonandManchester.Thissection quantifiesanddetailsthepercentageofenergysavingsbyelectrochromicwindowscomparedtostandardclearLoE Argon-filledglazingunits(basecase)inLondonandManchester.

Totalenergy

Fordouble-glazedunits,ECwindowscansaveupto21%oftotalenergyinLondonandupto24%inManchester whencomparedtothebasecase.Fortriple-glazedunits,ECwindowscansaveupto18%oftotalenergyinLondon andupto20.7%inManchesterwhencomparedtothebasecase.Electrochromicwindowshavenoconsiderable savingsinnorthwest,northandnortheastorientations.Inaddition,thesewindowsbecomeeffectiveonlyinlarger window-to-wallarearatios.Theexactpercentageofenergysavingsineachorientationandwindow-to-wallarea ratioareclearlygiveninthenextsections.Incontradictiontothehypothesis,itcanalsobeobservedthat electrochromicwindowssavemoreenergyinManchesterthaninLondon.

Thissectiontriestoanalyzetowhatextenttheelectrochromicunitshelpinenergysavingswhencomparedto standardclearLoEargon-filledunitsandinwhichlocationtheseunitsmakethehighestenergysavings.Fordoubleglazed(DG)units,thecomparisonisbetweenDGclearLoEargon-filledunitsandDGelectrochromicunits.For triple-glazed(TG)units,thecomparisonisbetweenTGclearLoEargon-filledunitsandTGelectrochromicunits.

Heatingenergy

Insouth,southeast,andsouthwestorientations,electrochromicwindowsarenotsoeffectiveinsavingheating energy.Inallotherorientations,ECwindowshelpinsavingheatingenergy.Fordouble-glazedunits,ECwindows cansaveupto17%ofheatingenergyinLondonandupto20%inManchesterwhencomparedtothebasecase.For triple-glazedunits,ECwindowscansaveupto9.6%ofheatingenergyinLondonandupto12%inManchester whencomparedtobasecase.TheenergysavingsarehigherinManchesterthanthatinLondon.Theexact percentageofheatingenergysavingsineachorientationandWWRsareclearlygiveninthenextsections.

RESULTS EFFECTOFLOCATIONONENERGY

Coolingenergy Lightingenergy

ThegraphsshowthatECwindowsareeffectiveinsavingcoolingenergy.Innorthwest,northandnortheast orientations,forsmallerWWRs,ECwindowsarenoteffective.Inallotherorientations,thereareconsiderable savingsincoolingenergywhenECwindowsareused.AstheWWRincreases,theenergysavingsalsoincrease.For double-glazedunits,electrochromicwindowscansaveupto42.4%ofcoolingenergyinLondonandupto51.2%in Manchester.Fortriple-glazedunits,ECwindowscansaveupto39.9%ofcoolingenergyinLondonandupto47.7% inManchestercomparedtothebasecase.TheenergysavingsinManchesterishigherthanthatofLondon.The exactpercentageofcoolingenergysavingsineachorientationandWWRsareclearlygiveninthenextsections.

ECwindowsarenoteffectiveinsavinglightingenergyinbothlocations.Theprobablereasonisthatwhenthe priorityisgiventoenergysavings,theglazingunitsgototintedstatewhenthereismoresunshine.Thiscanleadto anincreaseinlightingenergyconsumption.

FromallthegraphsitcanbesummarizedthatECwindowsaremoreeffectiveinManchesterthaninLondonincase ofsavingtotalenergy.ThoughECwindowsarenoteffectiveinsmallerwindow-to-wallarearatios,ithelpsin savingenergyconsiderablyforlargerwindow-to-wallarearatios.ECwindowshelpsavebothcoolingandheating energies;however,theydonothelpsavelightingenergy.Thepercentageofcoolingenergysavingsarelarger.

RESULTS

EFFECTOFGLAZINGTYPEONENERGY

Inthissection,acomparativeanalysisismadebetweenthetestcellsthatusedouble-glazedandtriple-glazedunits. Thisanalyseshowfartriple-glazedunitssaveenergywhencomparedtodouble-glazedunitsandquantifythesame. TheanalysisisdoneforbothLondonandManchester.

Itisgenerallysaidthattriple-glazedunitsaremoreeffectiveinsavingenergythandouble-glazedunits.Hence,here calculationshavebeenperformedconsideringthatenergiesfromdouble-glazedunitshavehighervalues.Sopositive valuesindicatethattriple-glazedunitsareeffectiveandnegativevaluesindicatethattheyarenoteffective.

London

Manchester

Inbothlocations,forclearLoEargon-filledunits,forlargerWWRs,thetriple-glazedunitsareseentobemore effectivethandouble-glazedunits.AstheWWRincreases,theeffectivenessoftriple-glazingincreases.However, forECwindows,triple-glazingunitsdonotmakeanysavingsinbothlocations.Thispointstothefactthattripleglazedelectrochromicunitsareineffectiveintheseclimates.Double-glazingunitsthemselvescanhelpinenergy savings.

Acomparisonwasmadebetweendouble-glazedECwindowsandtriple-glazedLoEargon-filledwindows.For LargerWWRs,ECwindowsperformedbetter,andmoresignificantsavingsweremadeinManchester.

Doubleglazedunit

Fromthestudiesitwasfoundthat,forlowerWWRs,clearLoEargons-filledunitsperformbetter.Whereaswhen theWWRsarelarger,ECwindowsaremoreeffective.Thegraphsforthepercentageofenergysavingsineach orientationandWWRforbothlocationscanbefoundintheprevioussection.Theexactpercentageofsavingsand theWWRsabovewhichECwindowsbecomeeffectivecanbefoundinthenextsections. Triple-glazedunitsalsoshowasimilartrendtodouble-glazedunits.ForlowerWWRs,clearLoEargon-filledunits performbetter,andforlargerWWRs,ECwindowsperformbetter.However,whencomparingdouble-glazedand triple-glazedunits,triple-glazedECwindowsdonotperformbetterthandouble-glazedECwindows.However,on comparingdouble-glazedECwindowsandtriple-glazedLoEargon-filledwindows,forLargerWWRs,EC windowsperformedbetter.

Trippleglazedunit

Unitswithinternalblinds

ThisstudycomparedtheECwindowswithclearloEargon-filledwindows.Thecomparisonwasdonewiththe clearstateofthewindows.However,inarealscenario,thesewindowsmayhaveinternalblindsorexternalshading devices.Theseshadingdeviceshelpinreducingoverheating.Inaddition,itmayalsoinfluencetheamountof daylightreceivedinsidetheroom.Theeffectoftheexternalshadingdeviceitselfisaseparatelargetopictobe studiedastherearevarioustypesofexternalshadingdevices.So,consideringthescopeandextentofthisstudy, onlytheeffectofinternalblindswasstudied.Thereareseveraltypesofinternalblinds.Inthisstudy,internalblinds withhighreflectivityslatscommonlyseeninofficebuildingsintheUKwerechosen.Simulationswererunforclear LoEargon-filledwindowswithinternalblinds,anditsresultswerecomparedwithitsclearstateandECwindows. Itwasanticipatedthattheenergyconsumptionofunitswithblindswouldbemuchhigher;hence,whencompared withthat,ECwindowscanmakelargesavings.However,onrunningsimulations,itwasfoundthatthereisonlya slightincreaseinenergythanthetransparentstate,andhencenosignificantchangeinthepercentageofenergy savingswasobserved.

RESULTS

EFFECTOFORIENTATIONONENERGY

Doubleglazed

ThegeneraltrendinbothglazingtypesisthatthelowesttotalenergyisforNorth,followedbyNorthwestand Northeast;EastandWest;Southeast,Southwest,andSouth.

ThegraphaboveshowsthatforclearLoEargon-filledunits,WWRsarecrucialbecausethereisaconsiderable variationinenergiesbetweendifferentWWRs.Inallorientations,theenergiesdropuntilacertainWWRandthen increase.Theratiotowheretheenergiesdropisdifferentfordifferentorientations.Energyperformanceinthe northeastandnorthwest,eastandwest,arealmostthesame.Thelinesofsoutheast,south,andsouthwestalso mergeatseveralpoints.Atotaloffourdifferentenergytrendscanbeobserved,andtheenergydifferencebetween thesefourtrendsincreasesastheWWRincreases.Thereisasignificantdifferencebetweentheseenergytrendsat largerWWRs.

InECwindowsalso,theseenergytrendscanbeobserved.However,theenergydifferencebetweenthese orientationsisnotverylarge.TheenergydifferencebetweenorientationsisnegligibleatlowerWWRs,andit slightlyincreasesastheWWRincreases.ThevariationofenergiesbetweendifferentWWRsisnotassignificant asinclearLoEargon-filledunits.However,thereisaclearpatternintheenergytrendsofdifferentorientations whenECwindowsareused.ThegeneraltrendisthattheenergiesdroptoaWWRof70%,slightlyincreaseto80%, andthendropagainto100%.ThelowestenergiesareforaWWRof70%.

Trippleglazed

Exceptfortheenergyvaluedifference,theenergytrendsoftriple-glazedunitsaresimilartothatofdouble-glazedunits.

RESULTS

EFFECTOFWINDOWTOWALLAREARATIOONENERGY

Totalenergy

WWRABOVEWHICHECWINDOWSBECOMESEFFECTIVE

TotalenergieswereplottedagainstWWRs.TheenergylinesofbothglazingtypescrossaboveacertainWWR,and ECwindowsbecomeeffectivebeyondthatratio.

PERCENTAGEOFTOTALENERGYSAVINGSBYECWINDOWSINDIFFERENT WWRANDORIENTATIONS

Inthetablesbelow,blankcellsrepresentnoenergysavingsbyECwindowsinthoseWWRs.Tablesclearlyshow largersavingsforhigherWWRsinsouthwest,south,andsoutheastorientations.Inaddition,theenergysavingsby ECdouble-glazedunitsaremuchmoresignificantthantriple-glazedunits.

London-Doubleglazed

Manchester-Doubleglazed

London-Trippleglazed

ItcanbeobservedfromthetablebelowthatthereisnosignificantdifferencebetweentheratiosofLondonand Manchester.ForManchester,whichisatahigherlatitudethanLondon,ECwindowsbecomeeffectivefromslightly lowerWWRthaninLondon.

London

Doubleglazed

North NorthEast

Trippleglazed

North NorthEast

Manchester

Doubleglazed

North NorthEast East

Trippleglazed

North NorthEast East

Manchester-Trippleglazed

RESULTS

EFFECTOFWINDOWTOWALLAREARATIOONENERGY

Heatingenergy

Theenergylinesofbothglazingtypesdonotcrosseachotherinnorth.ECwindowsperformbetterinthat orientation.However,inthesouth,thelinesmeetatlowerWWRsanddivergeathigherWWRs.Thisdenotesthat therearenosignificantheatingenergysavings.

PERCENTAGEOFHEATINGENERGYSAVINGSBYECWINDOWSINDIFFERENT WWRANDORIENTATIONS

TablesclearlyshowlargersavingsforhigherWWRsandinnorthwest,northandnortheastorientations.However, theenergysavingsbyECdouble-glazedunitsaremuchmoresignificantthantriple-glazedunits.Inthesouth, southeastandsouthwestorientations,ECwindowsdonothelpsaveheatingenergyforlargerWWRs.

London-Doubleglazed

Manchester-Doubleglazed

London-Trippleglazed

Manchester-Trippleglazed

RESULTS

Coolingenergy

ThegraphsbelowshowtherearesignificantcoolingenergysavingsbyECwindows

Thetablesbelowshowthatthelargestcoolingenergysavingsareinthesouth,southeastandsouthwest orientations.Thepercentageofcoolingenergysavingsislargerthanheatingenergysavings.So,itisevidentthatEC windowsaremoreeffectiveinreducingcoolingenergy.

London-Doubleglazed

Manchester-Doubleglazed

London-Trippleglazed

Manchester-Trippleglazed

RESULTS

EFFECTOFWINDOWTOWALLAREARATIOONENERGY

Lightingenergy

Asdiscussedearlier,thegraphsshowthatECwindowsareineffectiveinreducinglightingenergy.

Fromthestudies,itcanbesummarizedthatECwindowshelpreducetotalenergy,heating,andcoolingenergiesat largerWWRs.However,itismoreeffectiveinreducingcoolingloadsbutnotinreducinglightingenergy.

RESULTS

SENSITIVITYANALYSIS

Theprevioussectionsdiscussedthefourcrucialdesignparametersconsideredinthisstudy.Toidentifythemost influentialdesignparameter,sensitivityanalysiswasdoneofthefourparametersdiscussed.Atotalof20000 simulationrunswereperformedwiththehelpoftheOptimization+Uncertainty/Sensitivityanalysistoolavailable inDesignbuilder.Theanalysiswasdonein3mainsectionsand5subsections.Thefirstsetofanalysesconsidered allfourparameterstogether.Separatesimulationsweredonefortotal,heating,cooling,lightingenergiesand operationalcarbon.ThenextsetofanalyseswasdoneforLondonandManchesterseparately.Sothosesetsof studiesincludeonlythreedesignparameters.

Inthesensitivityanalysis,theadjustedRsquaredvaluerepresentsthegoodnessoffitofthecompletemodel.It indicateshowtheinputvariablesexplainmuchvariationintheoutput.Inalltheanalysesperformed,theadjusted Rsquaredvaluesarelow,suggestingthatthecurrentinputvariablescannotusefullyexplaintheuncertaintyinthe output.Othermoreinfluentialinputvariablesmightexistandcanbeincludedtoimprovetheresults,orthenumber ofsimulationrunscanbeincreased.Here,manynumberofsimulationrunswereperformed;hence,thisaspectdoes notbecomeareasonforasmallervalue.So,itcanbeunderstoodthatapartfromtheparametersdiscussedinthis study,othermoreinfluentialparametersexist,andsofurtherstudiescanbedoneinfuturetoidentifythesame.

Inaddition,thep-valuetellsiftheinputvariablehasastatisticallysignificanteffectontheoutput.Forexample,in alltheanalysisrunsperformed,alltheinputvariableshaveap-valuelessthan0.05,whichshowsthattheseinput variablesaresignificantandthatthereisahighconfidencelevelintheirrespectiveregressionresultvalues.These regressionresultscanrankthemostandtheleastsensitiveinputvariables.

AnothercriticalaspectistheStandardizedregressioncoefficient(SRC).Thisvaluetellstherelativesensitivityof theinputvariablestotheoutput.Itsabsolutevaluerankstheinputvariablesinorderofsensitivity/importance,and thesignidentifiesiftherelationshiptotheoutputisdirectorinverse.Finally,thelistranksthevariablesin decreasinglevelofimportance.(HighImportance: Green,MediumImportance: Yellow,LowImportance: Red).

Here,certainparameters'directorinverserelationsaredifficulttojustify.Inthisstudy,parameterslikeWWR,site orientationandglazingtemplatesarechallengingtobeanalyzedwithjustpositiveornegativevalues.Forexample, itisnotentirelycorrecttosaythatthetotalenergyconsumptionreduceswhentheWWRincreases.Becausethere arespecificorientationswherethereversehappens,thistrendmayalsobedifferentwithdifferentglazingtypes.So, itisimpossibletodetermineiftherelationshipbetweentheoutputandtheinputparameterisdirectorinversejust bylookingatthepositiveornegativeSRCvalue.However,thiscanstillhelpunderstandtheoveralleffectofall factorsconsideredinthestudy.

Withlocationtemplate

Thefirstsetofanalysesconsideredallfourdesignparameters.Separatesensitivityanalysiswasdonefortotal, heating,cooling,lightingenergiesandoperationalcarbon.Asaruleofthumb,10timesthenumberofparameters, 240,cangiveaconsiderablyfairresult.However,toincreasethereliabilityoftheresults,2000simulationrunswere performedforeachsetofanalyses.

Totalenergy

Whentotalenergyisconsidered,thelocationbecomesthemostcrucialdesignparameter.Thenegativeresult showsthat,aslatitudeincreases,thetotalenergyconsumptionreduces.ThisfactwasevidentwhentheLondonManchesterenergycomparisonwasmade.TheothertwoparametersWWRandsiteorientation,haveonlymedium importance,andthechoiceofglazingtypehasminorimportance.Theenergy-savingpotentialofECwindowsand variousotherglazingtypeswasdemonstratedintheprevioussections.However,otheraspectsbecomemore criticalwhentheoverallscenarioisconsidered,andtheglazingtypehastheleastprominence. Inthisanalysis,whentheorientationdegreeis0,thewindowfacesthesouthside;hence,0degreesrepresentthe south.Otherorientationsareconsideredintheclockwisedirection:45–south-west,90–west,135–north-west, 180–north,225–north-east,270–eastand315–south-east.So,theincreaseinorientationdegreesrepresentsthe changeinorientationsfromsouthtosoutheast.However,asdifferentorientationshaveadifferentrelationshipwith

theenergyconsumptiontrend,positiveornegativevaluesofthisparameterinthegraphcannotclearlysayits relationshipwiththeoutputparameter.

Thesamehappenswithglazingtypes.Glazingtypeswerearrangedasdouble-glazedunits,followedbytripleglazedunits.Theincreasingtrendjustdenotesthechangefromdouble-glazedtotriple-glazed.Betterperformance caneitherbebyECwindowsorclearLoEargon-filledunits.So,withthisparameteralso,positive,ornegative valuesindicateifdouble-glazedortriple-glazedperformsbetter.

Heatingenergy

Location,WWRandglazingtypebecomesessentialparameterforheatingenergy.Thelocationtemplateshowsa positiverelation,whichmeansthat,asthelatitudeincrease,theheatingenergyincreases.WWRalsoshowsadirect relationship.Theglazingtypeshowsanegativerelation,pointingoutthattriple-glazedunitshelpinsavingheating energycomparedtodouble-glazedunits.Siteorientationhasonlymediumimportanceinsavingheatingenergy.

RESULTS

SENSITIVITYANALYSIS

Coolingenergy

Likeheatingenergy,location,WWRandglazingtypebecomeessentialparametersforcoolingenergy.Different fromthegraphforheatingenergy,locationshowsanegativerelationshipwhichmeansthatasthelatitudeincrease, thecoolingenergydemandreduces.WWRshowsadirectrelationship.Itwasclearlyobservedfromthegraphsin theprevioussectionsthat,astheWWRincreases,heatingandcoolingdemandincreases.

Lightingenergy

WWRandglazingtypesbecomethemostcruciallightingenergyparameter,unlikeotheroutputs.AstheWWR increases,lightingenergyreduces.Theglazingtypeshowsadirectrelationship,whichshowsthattriple-glazed unitsincreaselightingenergydemands.Locationandorientationbecomeleastimportantparameters.

OperationalCarbon

ApartfromslightchangesinSRCvalues,theoperationalcarbongraphshaveasimilartrendasthetotalenergy graph.Therefore,thelocationtemplateisthemostcriticalparameter,andallotherparametershavemedium importance.

RESULTS

SENSITIVITYANALYSIS

LondonandManchester

ThissetofanalyseswasdoneseparatelyforLondonandManchesterandhenceconsideredonly3designparameters.Aseparateanalysiswasperformedforbothlocations'totalheating,cooling,lightingenergiesandoperationalcarbon. 1000simulationrunswereperformedforeachanalysis.

Totalenergy

ApartfromaslightvariationinSRCvalues,allthreeparametersbecomeessentialinbothlocations.ThemostimportantisWWR,followedbytheglazingtypeandsiteorientation. Bothlocationshaveasimilartrendinthecaseofheatingenergy.Alltheparametersbecomeessential.Theorderofimportanceissimilartothetotalenergy.However,thereisachangeintherelationshiptrendofeachparameter.All parametersbecomeessentialinManchester,whereassiteorientationhasonlymediumimportanceinLondon.

Heatingenergy

RESULTS SENSITIVITYANALYSIS

Coolingenergy

Coolingenergygraphsalsoshowasimilartrendinbothlocations.WWRbecomesthemostcriticalparameter,followedbytheglazingtypeandsiteorientation.However,thereisadifferenceintheimportanceoftheseparametersin bothlocations.Forexample,WWRandglazingtypehashighimportance,andsiteorientationonlyhasmediumimportanceinLondon.However,alltheparametersbecomeimportantinManchester.

Lightingenergy

Theorderofprominenceofparametersremainsthesameasforotheroutputs,however,siteorientationbecomesleastimportantwhenitcomestolightingenergy.

RESULTS SENSITIVITYANALYSIS

OperationalCarbon

Inallotheroutputparameters,LondonandManchesterhadasimilartrendintheorderofprominenceoftheparameter.However,thatisdifferentinthecaseofoperationalcarbon.WWRbecomesthemostinfluentialparameterinboth locations.InLondon,followingasimilartrendasthetotalenergygraph,glazingtypeandsiteorientationbecomethenextimportantparameters.However,siteorientationbecomesManchester'snextinfluentialdesignparameter, followedbyglazingtype.

ThoughthisstudydoesnothelpidentifytheeffectivenessofECwindows,ithelpsdeterminetheinfluentialparametersandtheirorderofprominence.Withthehelpofthesegraphs,designerscanmakedecisionsbasedonthelocations andpriorities.

Thisstudyevaluatedtheenergyperformanceofofficebuildingswithelectrochromicwindowsintheclimateofthe UK.Thestudywasperformedin2locations–LondonandManchester.LondonandManchesterexperience differentclimaticconditions.Adetailedclimaticanalysisandenergycomparisonwasmadeintheinitialstagesof thestudy.ArepresentativeofficetestcellwasmodelledinDesignBuilder,andatotalof2240simulationswere performed.Theannualtotalenergy,heating,cooling,andlightingenergieswereobtainedforacombinationof parameterslikelocation,glazingtype,window-to-wallarearatioandorientation.Theperformanceofdoubleand triple-glazedelectrochromicwindowswascomparedwithdoubleandtriple-glazedclearLoEargon-filled windows.Followingarethekeyfindingsofthestudy:

� ECwindowsareeffectiveintheclimateoftheUKwhenwindow-to-wallarearatiosarelarger.

� Incomparingtheenergydemandofthetwolocations,thetotalenergydemandinLondonishigherthanin Manchester.CoolingenergydemandwashigherinLondon,whereasheatingenergydemandwashigherin Manchester.

� LondonhasawarmerclimatethanManchester.AsmostofthereviewedliteratureonECwindows showedthattheyaremoreeffectiveinwarmerclimates,itwasanticipatedthatECwindowswouldsavemore energythanthebasecaseinLondon.However,contradictingthehypothesis,itwasfoundthatManchester'stotal energysavingswerehigher.

� ECwindowssavedupto21%oftotalannualenergyinLondonand23.9%inManchestercomparedtothe basecase.

� ECwindowscansaveupto17%ofheatingenergyinLondonand20%inManchestercomparedtothebase case.

� When42.4%ofcoolingenergyissavedinLondon,upto51.2%issavedinManchestercomparedtothe basecase.

� Contradictingthehypothesis,itwasobservedthatECwindowsmadenosignificantlightingenergy savings.

� Thestudywasperformedwithcurrentandfutureweatherfiles(2050,2080-4.5scenario).Therewillbea 5-6%increaseinenergydemandinthefuture.Forfutureweather,theeffectivenessofECwindowsincreasesfor London,whereasitdecreasesforManchester.

� Triple-glazedECwindowsareineffectiveinthisclimatecomparedtothebasecase.

� Comparingdouble-glazedelectrochromicwindowsandtriple-glazedclearLoEargon-filledunits, electrochromicwindowsperformedbetterinhigherWWRs.

� Totalenergysavingswerehighestinsouth,southeastandsouthwestorientations.Theseorientationsmade themostsignificantsavingsincoolingenergyandtheleastsavingsinheatingenergy.

� Generally,itwasfoundthatECwindowsareineffectiveintheNorthorientation,thoughconsiderable heatingenergyissaved.

� ThemostenergyefficientWWRfortheECwindowis70%.

� Inthefirstsetofsensitivityanalysisthatconsideredallfourparameters,‘Location’wasidentifiedasmost

crucialparameter.

� InthesecondsetofsensitivityanalysisperformedonLondonandManchesterseparately,‘WWR’was identifiedasthemostinfluentialparameter.

Asmentionedabove,resultsshowedthatECwindowsmadenoenergysavings.Itistobenotedthat,inthisstudy, ECwindowswerecomparedwiththeclearstateofLoEargon-filledwindows.However,inarealscenario,these windowsmayhaveinternalblindsorexternalshadingdevices.Hence,theenergyperformanceofwindowswith internalblindswasalsoobtainedthroughsimulations.However,itwasfoundthatthereisonlyaslightincreasein energythanthetransparentstate,andhencenosignificantchangeinthepercentageofenergysavingswasobserved. Here,thedefaultsettingsinDesignBuilderwereusedinthesimulation.Inreallife,theblindsmayremainunfolded forextendedperiods.So,performingsimulationswithalgorithmsmoresimilartomanualoperationspatternsmay yieldapositiveresult.

LimitationsandFutureResearch

Consideringthetimeframeandextensivenumberofsimulationsinvolved,thestudywaslimitedtocertainaspects ofECwindows.Manyotheraspectscouldnotbeincludedinthestudy.However,futureresearchworks,andmore extensivestudiescanconsidersomeaspectsnotdiscussedhere.

Thereareseveralpossibilitiesforfutureresearchonthissubject.Someofthemare:

� IncludingmorelocationsinthehigherlatitudesoftheUK.AclearpictureoftheeffectivenessofEC windowscanbeobtainedonlywhenotherlocationswithinthecountrythatliesinhigherlatitudesareincluded.

� Thesamestudycouldbedonetovalidatetheresultsusingothersoftwarepackages.

� Onlykeydesignparametershavebeenconsideredinthisstudytoanalyzeenergyconsumption.However, otherdesignparameterscaninfluencetheseenergiesmorethanthoseconsideredhere.Moreextensivestudiescan considerandcomparetherelativeinfluenceofdifferentotherdesignvariables.

� Annualenergyperformanceshaveonlybeencomparedinthisstudy.Thestudyhasnotincludedaseparate analysisofthesummerandwinterperiods.

� Inthisstudy,thecontrolprioritywasenergy.Infutureworks,theresultsofothercontrolstrategiescould beanalyzed.

� Currently,ECwindowsthataredividedintodifferentzones,eachofthemhavingdifferentcontroloptions, areavailableinthemarket.Studiescanbedoneonthoseupdatedversions.

� TheCO2savingpotentialscouldbestudiedandcomparedwithotherglazingtypes.

SEMESTER2

INTRODUCTION

PROJECTBRIEF|ABSTRACT|AIMS&OBJECTIVES

Project444isasustainablesocialhousingschemedesignedforOneManchester.Theschemeconsistsofindividualreplicablerowseachconsistingof4StudioApartments,41-BedroomApartments,and42-Bedroomduplexhomes,allarrangedwithinaterracedhousingformat.

Thehousingsectoraloneisresponsiblefor17%oftheUK'scarbonemissions.Theoperationalcarbonofbuildingshighly contributestoglobalwarming.Theaimofthisprojectistodesigncompactandenergyefficienthomes.Theembodied carbonandcostoftheprojectwasalsoconsidered.Thesustainabilitystrategyincludesthecreationofacomfortable andhealthyenvironmentwithinthehousesbyusingefficienttechnologysolutionsandrenewablesourcesofenergyin ordertoachievehighbuildingenergyefficiency.Theenergydemandwasreducedbytheuseofpassivestrategies,and anincreaseintheenergyefficiencyoffacilitiesanduseofrenewableresourcesavailableonsite.

Thisreportbeginswillexaminationofcasestudiestolearnfromprevioussustainablesocialhousingschemes.Thesite, whichislocatedintheBradforddistrictofEastManchester,isevaluated.ThesiteanalysiswillbefollowedbyathoroughanalysisoftheclimaticconditionsofManchestercurrentlyalongwithanevaluationofManchester’sfutureclimaticconditionsfor2030,2050,and2080basedonRCP4.5(RepresentationConcentrationPathway)Scenario.

Thedesigndevelopmentsectionisadetailedaccountofallthedesigndeliberationsbasedonqualitativeresearchand quantitativeinvestigationandcalculationsbasedondatafromDesignBuilder.Thefinalplansfortheprojectweredevelopedwiththeoptimumform,shape,andfloorplans.Thewindowsandshadingwereoptimisedtomaximisesolar gainanddaylightingwhilelimitingoverheating,forwhichadetailedstudywascarriedout.Further,thematerialsused wereevaluatedandabriefoverviewofbuildingconstructiondetailsweredrafted.

TheLifeCycleanalysisofthebuildingwascarriedouttohelpascertaintheembodiedcarbonandlifecyclecostofthe buildingfollowedbycalculationsforsolarpanels.Thesustainabilitystrategiesimplementedinthisbuildingalongwith theefficientfabricandformmakesthisaCarbonNegativebuildingwhichwasdesignedmeticulouslywithnotonly environmentalaspectsustainabilityinmindbutalsothesocialandeconomicaspect.Thisschemewouldhelpcreateup to24comfortable,healthy,andharmoniouscommunitytoliveinformanydecadestocome.

CASESTUDIES

1.KNIGHT’SPLACE-EXETER

Client: ExeterCityCouncil

Architect: GaleandSnowden

Theholisticdesignstrategyallowstheunitstobeoperatedwithoutaconventionalheatingsystem.

Atthesametime,itwillavoidoverheatinginthesummerandaimstohaveaminimalenvironmental impact.Thequalityofmaterials,designandlandscapingoffersresidentsasenseofplacewithadistinctivemoderncharacterwhichtheycantakeprideinoverthelongterm.

ProjectSummary

•18Units

•15-monthconstructionprogramme

ProjectDrivers

•FuelPoverty

•EnergySustainability

•FutureClimateChange

•LowMaintenance

•Downsizing

•HealthyBuildings

•BuildingdesignisbasedonthePassivhausmethod.

•Designedtomeetfutureclimatechange.

•Designedtomeet code4 ofthe CSH

•Fullycompliantwithlifetimehomestandards.

•Privategardensdesignedusing permacultureprinciples.

•Solarpanelsservingeachindividualunits.

•Designedtomeetbestpracticedaylightlevels.

•100%energyefficientlightfittingsthroughout.

•Independentlyassessedunderthebuildingforlifestandardwithafinalscoreof18.5outof20.

•Usinglowwaterusefittings,thewaterconsumptionwasreducedtolessthan80litres/person/day

SITELAYOUTPLAN

EnergyPerformance

CASESTUDIES

2.KILLYNUREGREEN,CARRYDUFF,NORTHERNIRELAND

Client:ChoiceHouseAssociation

Architect:PDPLondon

Description

SocialandAffordableZeroCarbonHousingScheme. CIBSEprojectoftheyearaward2018.

Overview

LocatedintheurbanareaofCarryduffandalongabusy commuterroad,thisbrownfieldsiterequiredsignificant cutandfillgroundworksalongwiththeinstallationof multipleretainingstructures.Theaimofthisprojectwas toprovidethermallyefficienthomesthatwouldleadthe wayforfuturedevelopments.

Bycombiningafabricfirstapproach,complimentedwith sustainabletechnologies,eachhomewasdesignedto achieveanimprovementof60%moreoncurrentbuildingregulations.

SpecialFeatures

Thedevelopmentswasdesignedtomeetminimumcode 5oftheCodeofSustainablehomes,utilizingmodern methodsofconstruction.ItwastobethefirstCodeLevel 5schemeinNorthernIrelandandoneofthelargestinthe UK.

TopographyInfluence

Thebuildingsarecarefullypositionedtofollowthenaturalundulationsofthesite,withshorthousingterraces tieredacrosstheexistingsitelevelsandcontours.The designsoughttotakeadvantageoftheslopingsiteby spacingthedwellingstomaximisedaylightandcollection.

Design,ConstructionandDeliveryprocess

•Fabricfirstapproachwasadoptedtoreduceenergyconsumption.

•Prefabricatedstructuralsystemwasutilizedtoachievehighlevelsofthermal insulationandairtightness.

•Timberframedwintergardenswasdesignedasapassivesolution,aninsulatedbufferfortheresidentsfromoutsideconditions.

•Airtightnesstestswerecarriedoutatanearlystageasaqualitycheckandthe wintergardensweremodelledinIESatdesignstagetoensureoptimumsolar gain.

CASESTUDIES

3.EMHHOMES,TOWNSTREET,SANDIACRE,NORTHERNIRELAND

BuildingServices

BuildingServices

• Gascondensingboilertoprovide

ildingServices

spaceanddomestichotwater

Gascondensingboilertoprovide

• Radiatorsystemsignificantly reducedtoonlyupperandground floorbathrooms

Overview

SocialandAffordablepassivehousingwithextremely lowenergybills.Oneofthefirstpassivhausprojectsin theUK ThisdevelopmentatTownstreet,Sandiacreconsists ofthirty-sixhousesandfourflatsalltothesame passivhausfabricspecification.Fouroftheseare passivhauscertified,whiletheresthavebeenconstructedtothesamespecification.

SpecialFeatures

Theprojectteamincludedapassivhausconsultant,an architectandahousebuilderandtimberframesupplier. Byengagingthesupplychainearlywithintheproject, bothproductandprocessimprovementshavebeen usedtodeliverhighlyenergyefficienthomesatacost viableforsocialhousingproviders.

ProjectChallenge

Oneofthecentralchallengeswastoworkwiththeselectedmanufacturerofaconventionaltimberframed housingsystemtoraiseitsenergyefficiencyperformancetopassivhausstandard.Thisrepresentedadesign challengeforbotharchitectsandconsultants.There wasalsoandup-skillingchallengeforthecontractorto deliverarobuststrategyforthedeliveryofairtightconstruction.

Costofradiatorsinallhousetypeswasreducedbyusingtheventilationsystemtodistributetheminimal amountofheatrequired.

TheoptiontoachieveCodeforSustainableHomes

Level4 wasamajorchallenge.

GroundFloorPlan

GroundFloorPlan

DeliveryProcessandConsiderations

• Mechanicalventilationwithheat recoveryMVHRsystems.

•

DeliveryProcessandConsiderations

• Option1-FabricFirstenergydemand reductions

KeyLessons

DeliveryProcessandConsiderations

• Option1 FabricFirstenergydemand reductions

• Option2-Technologyfirstlowandzero carbonenergygeneratingsystems.

•EnergyefficientapproachtomeetCode5forsustainablehomes.

• Option1-FabricFirstenergydemand reductions

• Option2-Technologyfirstlowandzero carbonenergygeneratingsystems.

•Decarbonizationwasinfocusfromtheonset.

• Fabricfirstapproachintheformof passivhausspecificationwasadopted Itwas amorerobust,long-termsolutionforthe development.

• Option2-Technologyfirstlowandzero carbonenergygeneratingsystems.

•Innovativeproductsandsystemstoachievehigh levelsofthermalinsulationandairtightness.

• Fabricfirstapproachintheformof passivhausspecificationwasadopted.Itwas amorerobust,longtermsolutionforthe development.

•Factoryfittedstructuralsystemsandcomponents forhighlevelaccuracyinassembling.

• Standardtimberframeconstruction

• Standardtimberframeconstruction

• Highinsulationandairtightnesslevels

• Fabricfirstapproachintheformof passivhausspecificationwasadopted Itwas amorerobust,long-termsolutionforthe development.

•LowembodiedenergymaterialswithlowUvalues.

Productsandsystems

• Standardtimberframeconstruction

• Nothermalbridges,thermalby-passorair leakages.

• Nothermalbridges,thermalbypassorair leakages.

Highinsulationandairtightnesslevels

• Highinsulationandairtightnesslevels

PRODUCTSANDSYSTEMS

PRODUCTSANDSYSTEMS

•TimberFramewith140mmmineral

wool,100mmPIR,50mmcavity withbrickorblockouterleaf

Client:NorwichCityCouncil

Architect: MikhailRiches

Description

GoldsmithStreetinNorwich,thewinnerofthe2019Stirlingpriceisa100%socialhousingdevelopmentforNorwichCityCouncil.Itcomprisesof93Passivhaushomesspreadacross7blocks alignedin4simplerowsonatraditionalstreetpattern.

SITELAYOUTPLAN

EARLYCONSIDERATIONS

Costsavingsweremadeearly inthedesignprocessbymaking significantalterationstothe brickwork,roofandfoundation packages,whichdidn’taffect energyperformance.

ARLYCONSIDERATIONS

ThermalEnergyDemand

ThermalEnergyLoad

PrimaryEnergyDemand

SITELAYOUTPLAN

SITELAYOUTPLAN

EARLYCONSIDERATIONS

EarlyConsiderations

ThermalEnergyDemand

=123k

SITELAYOUTPLAN

Contemporarymaterialsinclude blackglazedpantilestraversing fromrooftowall,contrasting lightcolouredbrickand perforatedmetalbrisesoleil.

tsavingsweremadeearly hedesignprocessbymaking ificantalterationstothe ckwork,roofandfoundation ckages,whichdidn’taffect rgyperformance.

LYCONSIDERATIONS

Costsavingsweremadeearly inthedesignprocessbymaking significantalterationstothe brickwork,roofandfoundation packages,whichdidn’taffect energyperformance.

Costsavingsweremadeearlyinthe designprocessbymakingsignificantalterationstothebrickwork,roofand foundationpackages,whichdidn’taffectenergyperformance.

ENERGYPERFORMANCE

SITESECTION:

Contemporarymaterialsincludeblack glazedpantilestraversingfromroofto wall,contrastinglightcolouredbrick andperforatedmetalbrisesoleil.

Airtightness

=0.56ACH@50pascals

temporarymaterialsinclude ckglazedpantilestraversing mrooftowall,contrasting tcolouredbrickand oratedmetalbrisesoleil.

blackglazedpantilestraversing fromrooftowall,contrasting lightcolouredbrickand perforatedmetalbrisesoleil.

Narrowstreets,carefullyconsideredwindowplacement,andcleverlyslopedroofs maximizedaylightintoadensedevelopmentthatdoesnotfeeloppressiveorunsafe. Parkinghasbeenpushedtotheperimetertohelpmaintainopenness.

ENERGYPERFORMANCE

ThermalEnergyLoad

Airtightness

=0.56ACH@50pascals

RGYPERFORMANCE

savingsweremadeearly hedesignprocessbymaking icantalterationstothe work,roofandfoundation ages,whichdidn’taffect gyperformance. emporarymaterialsinclude glazedpantilestraversing rooftowall,contrasting colouredbrickand

Primary EnergyDemand

SITESECTION:

CASESTUDIES

SUMMARY-VALUESFORREFERENCE

CO2emissions Airtightnesslevels Energydemands Walls–Uvalues Floor–Uvalues Roofs–Uvalues Glazing–Uvalues ThermalBridging

Fabricenergy efficiency

StandingsCourtsocial housingdevelopment -

PassivhausandCSH level4standards

StandingsCourtsocial housingdevelopment–CSHLevel5

EMHHomes–Townstreet,Sandiacre Tobepassivhaus certified

Knightsplace–Rowan house,ExeterCity Council

PassivhausandCSH level4standards

DER=10.23kg/m2/year <0.6ACH <120kWhper/m2/year 0.11W/m2K 0.08W/m2K 0.10W/m2K 0.9-1.0W/m2K

DER:-0.2kg/m2/year,Net CO2 emmisions:9.7kg/ m2/year 0.25ACH 1,270.7kWh/year/dwelling 0.14W/m2K 0.1W/m2K 0.1W/m2K 0.9-1.0W/m2K

12.5kg/m2/year 0.49–1.5m3/hm2 SpaceHeatDemand =11 kWh/m²peryear PeakHeatLoad =10W/m² 0.11W/m2K 0.12W/m2K 0.10W/m2K 0.84W/m2K G=0.61–Trippleglazed Y<0.07W/m2K(average) 29kWh/m2/year

<0.6ACH <0.12W/m2K <0.10W/m2K <0.11W/m2K <0.85W/m2K Thermalbridgefree

KillynureGreenlow energyhousing CSHlevel5 3.38to10.11kg/m2/year 1–3m3/hm2 35kWhper/m2 0.13W/m2K 0.13W/m2K 0.9W/m2K Y=0.04W/m2K

WimbishPassivhaus–SaffronWalden,Essex PassivhausandCSH

Lisnahullterrace, dungannon PassivhausandCSH level4standards

ConnellGardens

ManchesterCity Council’sregeneration planfortheGortonarea

GoodHomesAlliance OneBrighton Retrofit

Peaksarenomorethan 1200ppm 0.45ACHaverage

104÷111kWh/m2a(<120 kWh/m2aPassivHaus), Heatdemand--South facing=12kWh/m2a(<15 kWh/m2aPassivHaus) -Northfacing=19kWh/ m2a

0.09W/m2K 0.07W/m2K 0.08W/m2K

Windows–0.77W/m2K Doors–0.80W/m2K

<0.6ACH <120kWhper/m2/year 0.125W/m2K 0.143W/m2K 0.133W/m2K

Camdenpassivhaus London’sfirstcertified passivhausbuilding

Virido CodeforSustainable HomesLevel5

Passivefishermen's cottagesonNorfolk

coast

CodeforSustainable HomesLevel4

2/85m3/h/m2at50Pa, betterthanthetargetof 5m3/h/m2at50Pa.

un-bridgedU-valuesof 0.21W/m2Kandbridged U-valuesof0.25W/m2K

U-value-0.19W/m2K

U-value-0.80W/m2K. g-value-0.46 tripleglazedandlow-E coated

≤0.6ACHat50Pa 99kWh/(m2a)

Lower0.125W/m2K, Upper0.116W/m2K 0.103W/m2K

Flatroof0.067W/m2K, Slopingroof0.116W/m2K Terrace0.139W/m2K

U-value:windows0.76 W/m2K U-value:doors0.78W/m2 K

Zerocarbon(operational) 1.5m³/h/m²@50Pa

FabricEnergyEfficiency (FEES):39and46kWh/ m²/yr EnergyUseIntensity (EUI):70kWh/m²/yr (RIBA2025)

0.60ACH 108kWh/m2/yr

0.12W/m²K 0.1W/m²K 0.1W/m²K

Brick-cladwalls-0.096 W/m²K

Timbercladwalls:0.104 W/m²K 0.078W/m²K

Door–0.62W/m²K Windows–0.9W/m²K average

Mainroof:0.079W/m²K Pitchedroof,sloping ceilings:0.079W/m²K 0.85W/m²K

CASESTUDIES

CaseStudySimilarities SummaryofDesignStrategies

•Timberconstruction

•MVHRsystems

•Fabricfirstapproachemphasized

•Lowu-valuematerials

•Naturalventilationprioritized

•Compactbuildings,lowformfactor

•Dualaspectconsiderations

•Avoidanceofsingleaspectfacingunits

•Phasedconstruction

•Maximumofthreefloors

•Avoidanceofovershadowing

•Carefulselectionofconstructionmethod-toensurerepeatability.

Thestrategiesusedinthisproposalforasocialhousingat

Manchesterincludeacombinationofenvironmental,social,and economicfactorsaimatimprovingsocialinclusiveness,cohesion, andintegration.Thesefactorsaregenerallyoutlinedintheconsiderationsgivenbelow.

LIGHTING

•Naturallightingprioritized

•Energyefficientsystems

•Energysavingfeatureslikedaylightsensors,absencedetection

•Southfacingfaçadeandgardens

•Permaculturelandscapingprinciples

•Parkinginfrontofbuilding

SITE BUILDINGORIENTATION

•East-westorientation

•Sizingwindowsforsolargains

•Ventilationprioritized

•Entrancedoorfromstreets

•Noovershadowingwithadjacentbuildingonsite

•Viewtoparking

BUILDINGFABRIC

•Fabricfirstapproachprinciples

•Thermallyefficientbuildingfabric,lowembodiedcarbonmaterials

•Simplebuildingformforimprovedformfactor

•Lowmaintenance

•Locallysourcedmaterials

•Lesstransomsandmullionsinwindows

•Demountablepartition

CARBON

•Cycleroutesandfootpathsforreducedemissionsfromuseof vehicles

•lowembodiedcarbonmaterialsuse

•accesstopublictransportroute

•biodiversitypromotedthroughlandscaping

•EVChargingspotsprovided

•Treeplanting

•Renewableenergygeneration

VERTICALMOVEMENT

•Staircaseprioritizedovermechanicallifts

COOLING

•Sitelandscapingaids

•Shadingdevices

•Recessedbalconies

•Naturalventilation

•Roofoverhangs

•Setpointscoolingsysteminstallation

VENTILATION

•Mixedmodeventilationsystem.CombinesNaturalandmechanical

•Lowroomheight

•Airtightnessof3m3/m2h@50pa

ENERGYUSEANDEFFICIENCY

•Performancetargetforenergyconsumption

•PVpanelsintegrationwithgrid

•Airsourceheatpumps

•Meteringdevices

•Electricvehicleintegrationpoweredusingsolarpanels.

•WATER

•Rainwaterharvesting

•greywaterreuse/recycling

•Energyefficientsystems

•Energysavingfeatureslikedaylightsensors,absencedetection

STANDARDS

SUMMARY

Eachoftheprojectsdiscussedinthecasestudies,havefollowedvariousstands.Henceitwasnecessarytomakeadetailedstudyofthesestandsandmakeacomparisonsothatwhiledesigning,eachof theaspectscouldbebenchmarked.Tableshowsthesummaryofcomparisonofvariousstandards.

LETI

Manchester standard Passivhaus standard

Fabricvalues

Walls 0.13-0.15

Futurehomesstandard

UKGBCNetZero Wholelifecarbon AECBBuilding Standard RIBAStandards (notional building) (dwellingbuilt withaheatpump)

Externalwalls 0.13-0.15 0.18 0.18

Semi-exposed walls 0.18 0.18

Partywalls 0.16-0.18(eg.dwelling/ corridor) 0(refertable) 0(refertable)

Floor 0.08-0.10 0.08-0.10(GF) 0.13 0.13

Roof 0.10-0.12

Flatroof-0.10-0.12, Pitchedroof0.10-0.12 0.11 0.11

Roofwindows 1.2(wheninvertical position) 1.2(wheninvertical position)

Rooflights 1.7 1.7

Exposedceiling/floors

0.13-0.18 0.13-0.15(exposed soffit)

Windows 0.80(Trippleglazing)

≤0.80W/m2K (WindowinstalledU value≤0.85W/m2K) Trippleglazed(0.8-1)

Doors 1 ≤0.80W/m2K

Opaquedoor

1(<30%glazingarea) 1(<30%glazingarea)

Semi-glazeddoor 1(30-60%glazing area) 1(30-60%glazing area)

Efficiencymeasures

Airtightness

Thermalbridging

Gvalueofglass

Ventilationsystem

<1(m3/h.m2)@50Pa

≤0.6ac/h(n50) 5m3/(h.m2)@50Pa 5m3/(h.m2)@50Pa

0.04(yvalue) psi≤0.01W/mK

0.6-0.5 ≥0.5

MVHR-90% efficiency-≤2m (ductlengthfrom untiltoexternalwall)

MVHR-heatrecovery efficiency-≥75%, electricalefficiency≤ 0.45Wh/m3

Naturalventilation withintermittent extractfans

Naturalventilation withintermittent extractfans

≤1.5h -1 (≤3h -1)

Psiexternal<0.01 W/mK(Calculatedif> 0.01W/mK

STANDARDS

SUMMARY

Windowtowallarea

ratio

Orientation

Daylighting

Energyconsumption

LETI Manchesterstandard Passivhausstandard

Futurehomesstandard

UKGBCNetZero Wholelifecarbon AECBBuilding Standard RIBAStandards (notionalbuilding) (dwellingbuiltwitha heatpump)

Sameasforactual dwellingnotexceedinga totalareaofopeningsof 25%oftotalfloorarea

North 10-15% 10-15%

East 10-15% 10-20%

South 20-25% 20-30%

West 10-15% 10-20%

Within30degofdue south

Sameasforactual dwellingnotexceedinga totalareaofopeningsof 25%oftotalfloorarea

35KWh/m2/yr

<60KWh/m2/yr<35 KWh/m2/yr(future uplift)

≤120KWh/m2/yr

PassivhausClassic-≤60 KWh/m2/yr

PassivhausPlus-≤45 KWh/m2/yr

PassivhausPremium-≤30 KWh/m2/yr

Spaceheatingdemand

Spacecoolingdemand

Renewableenergy

Formfactor

Embodiedcarbon

15KWh/m2/yr 15KWh/m2/yr

15KWh/m2/yr

100%

1.7to2.5(refertable)

2021-2025-20%ofGF space2025-PV installation40%GFspace

PassivhausPremium-≥ 120KWh/(m2ground*a) PassivhausPlus-≥60 KWh/(m2ground*a)

≤3Areato Volumeratio≤0.7m²/m³

PVsystem:KWp=40%of GFareaincluding unheatedspacces/6.5

35-40KWh/m2/yr(From 2025-Regulated+ Unregulated) VariesKWh/(m2.a)

>2%av.daylightfactor,0.4 uniformity

Operationalenergy Businessasusual–120 KWh/m2/yr

2025targets-<60KWh/ m2/yr

2030targets-<35KWh/ m2/yr(min50% reductionfromcurrent business-as-usual baselinefigures) Currentgoodpractice (2021)–60KWh.m2/y (GIA)nogasboilers

15KWh/m2/yr

≤40KWh/(m2.a)DeliveredHeatand cooling

2.6KWPVinstallation on80%ofnewhomes from2020-2050 ≤75KWh/(m2.a)

<500KgCO2/m2

<500KgCO2e/m2<300 KgCO2e/m2(from2028)

Businessasusual–1200 KgCO2e/m2

2025targets-<800 KgCO2e/m2

2030targets-<625 KgCO2e/m2 Currentgoodpractice (2021)-LETIBandD 1000KgCO2e/m2

STANDARDS

SUMMARY

LETI Manchesterstandard Passivhausstandard

Heatingandhotwater

Potablewateruse

Summeroverheating

CO2levels

VOCs

Formaldehyde

Futurehomesstandard

Wholelifecarbon AECBBuilding Standard RIBAStandards (notionalbuilding) (dwellingbuiltwitha heatpump)

UKGBCNetZero

Fuel Fossilfuelfree Fossilfuelfree Mainsgas Mainsgas Lowcarbonheating systems

Heating 10w/m2peakheatloss (includingventilation)

SpecificPeakload≤10 w/m2

Boilerandradiators, Centralheatingpump 2013orlater,inheated space,Designflow temperature=55degC

Airsourceheatpumpand radiators,Designflow temperature=45degC, Spaceheatingefficiency= 250%

lowcarbonheating(eg: heatpumpsor connectionstonon-fossil fueldistrictheat networks

Hotwater

Maxdeadlegof1lfor hotwaterpipework

DHW peak 6w/m2

Waste Water heat recovery (WWHR)

20%demandreduction (comparedtoPartL2013)

Heatedbyboiler(regular orcombi),separatetime controlforspaceand waterheating.Boiler efficienceySEDBUK2009 =89.5%

Waterheatingefficiency= 250%.Storedhotwater incylinder,heatedbyair sourceheatpummpwith back-upimmersion heating.separatetime controlforspaceand waterheating.

>25degC≤10%ofyear (recommended<5%)

Allshowersconnectedto WWHR,including showersoverbaths. InstantaneousWWHR with36%recovery efficiencyutilisationof 0.98

None

Businessasusual–125l/ p/day(Building regulationsEnglandand Wales)

2025targets-<95l/p/day

2030targets-<75l/p/day Currentgoodpractice (2021)–110l/p/day

<10%(<5%recommended) 25-28oCmaximumfor 1%ofoccupiedhours

<900ppm

<0.3mg/m3

<0.1mg/m3

STANDARDS

SUMMARY

LETI

Materials

Siteemissions

Manchester standard Passivhaus standard

Futurehomesstandard

UKGBCNetZeroWholelife carbon AECBBuilding Standard RIBAStandards (notionalbuilding) (dwellingbuiltwitha heatpump)

•20%reductioninmaterial usagethroughdesignefficiency by2050

•10%reductioninmaterial demandby2040through increasedmaterialreuse

•80%reductionin constructionsiteemissionsby 2050

•50%reductionin constructionmaterial transportationemissionsby2050

Lighting Fixedlightingcapacity(lm) =185xtotalfloorarea, Efficacyofallfixedlighting =80lm/w

Acousticcomfortcriteria

Maximumsoundfrom

MVHRunit

35dB(A)

Maximumtransfersoundin occupiedrooms 25dB(A)

Fixedlightingcapacity(lm)= 185xtotalfloorarea,Efficacy ofallfixedlighting=80lm/w

SITEANALYSIS

Historically,thedistrictofBradfordwasaforestedareawhichbloomedduringtheindustrialrevolution.Theareahadcoalpitswhichisthemainenergysourcethatpoweredironmills,brickworks,cottonmills,andchemicalworks.Duringtheindustrialrevolution,manyterracedhouses werebuiltinthisarea.TheconstructionoftheEthihadstationalongwiththeNaturalCycling CentreveledromeandtheAsdaSuperstorehashelpedregenerateBradfordwhichwaspreviously derelict.Bradfordwouldbeperfectforthedevelopmentofasocialhousingcommunityasitisanup andcomingareaandhasgreatpotentialforgrowth.

Location

Thebuildingsaroundthesitearemostlylowriseresidentialrowhouses.ThesitehasplentyofvegetationandislocatedoppositeBradfordpark.ThesiteislocatedinBradford,2.5kmfrom ManchesterPiccadillyStation.Itiswellconnectedtotherestofthecityduetoitscloseproxmity totheEthihadStatdium.

SunpathandWinddirection

PredominantwindsflowfromtheSouthWestwhichisalsotheareamostpronetoexcessivesolar

facademustbeappropriatelyshadedandwellinsulatedto

SITEANALYSIS

Access

ETHIHADSTADIUM

BRADFORDPARK

Althoughtheentrancetothesiteisonaminorroad,thesiteislocatedclosetomanyprimaryandmainroadsthat connecttotherestofthecity.Therearemanybusstopsandstationsaroundthesite.VeloparkTrainstationisashort 12minutewalkfromthesite.

Sound

TheEthihadstadium,theTownleyPub,andtheBradfordParkhavepotentialto produceloudnoisesbutontheotherhand,thesiteissurroundedbytreeswhichare noisebuffers.

Materials Vegetation

Mostofthebuildingsaroundthesiteareresidentialterracehousescladindifferent typesofbrick,somewhichhaveconcretewalls.Thegreypanelsandglassfromthe Stadiumosalsovisiblefromthesite.

ThesitehastreecoverontheWestandtheSouth-East.Thetreesaredeciduousand shedtheirleavesintheWinterwhichwillallowsolargain. Sincethetreesarewelldeveloped,theywillprovideprotectionformwinds throughouttheyear.

Floodrisk

Thesiteislocatedfar awayfromanypotential floodzonesandhenceis notatrisk.Thesitehas plentyofgreenspaces thatimprovedrainage. Permeablepavements andarainwaterharvestingsystemwillbeincorporatedtofurtherimprovedrainageand futureproofthesite againstflooding.

CLIMATEANALYSIS

Temperaturerange Monthlydiurnalaverages

Temperaturesinthisregionfluctuatebetween10°Cto29°Cinthesummersand15°Cto-3°Cinthe winters.Variationindiurnaltemperatureisrelativelylow(between5°Cto10°C).Thebuildingwill requiremechanicalheatingforduringwinterandwillneedtobehighlyinsulated.

Bothtemperaturesandsolarradiationarequitelowinthisregion.Thehousewillneedtomaximize solargainduringwintermonths.Thereisasignificantdifferenceindiurnaltemperarureshence thermalmassmayproveusefultohelpregulatetemperatureinthemicroclimate.

RadiationrangeIllumination

Thereisanopportunitytodecreasetheheatingloadbyincreasesolargainbythroughexposuretothe Southduringthewintermonths.

Illuminationisquitelowinthisregion,eseciallyduringthewintermonths.Largewindowsand skylightswouldhelpmaximizedaylighting.

CLIMATEANALYSIS

ShadingChartWindData

CLIMATEANALYSIS

AverageAnnualTemperature:11°C

HighestTemperature:29°CLowestTemperature:-3.5°C

AverageAnnualTemperature:12°C

HighestTemperature:30.5°CLowestTemperature:-3°C

AverageAnnualTemperature:11.5°C

2020 2030 2050 2080

HighestTemperature:30°CLowestTemperature:-3°C

AverageAnnualTemperature:12°C

HighestTemperature:31°CLowestTemperature:-2°C

CLIMATEANALYSIS

Thereisagradualincreaseincomforthoursfrom4.6%ofhoursto8.3%from2020to2080andrequirementforshadingisalsoshowntoincrease.Thenumberofhoursthatabuildingcanmaintaina comfortableindoortemperaturebasedoninternalheatgainsaloneisshowntoincreasefrom32%ofhoursto38%.Thedemandforheatingissettodecreasefrom51.4%to42%by2080whichalsoresults inanincreasedneedforcooling.Passivesolargainwillsignificantlyreducetherequirementformechanicalheating.

CLIMATEANALYSIS

DESIGNDEVELOPMENT

INITIALDESIGNPLAN

CASESTUDYINFERENCE

SITEPLAN

Terracedhouseswithcompactfloorplans

Fabricfirstapproach

Increasethermalefficiencyofthebuildingtoreduceenergyconsumption

BUILDINGDESIGN PASSIVESYSTEMS

Largeshadedwindowstomaximizedaylightingbutalsolimit

overheatingduringthesummermonths

Gardenandlivingspacesorientedtowardsthesouth

OTHERSYSTEMS

MVHRsystemforheatingandventilation

Solarpanelsforenergyproduction

Rainwatercollection

REDUCINGEMBODIEDCARBON

Useofprefabricatedunits

Useoflocallysourced,sustainablematerialswithlowembodied carbon

Lowwaterusefittingstoreducewaterconsumption

CONSTRUCTIONANDPOSTCONSTRUCTION

Constructionshouldbecarriedoutinanefficientandsystematic mannerusingmany.Prefabricatedcomponentsthatcouldeasily beputtogetheronsite,ensuresrepeatability.

Airtightnesstestsandthermalscansandotherpostconsttruction evaulationsshouldbecarriedouttoensureenvelopefficiency.

50m

52m

Thesitehasacommunitycentrewhichisstillusedbythecommunity.Thememorialgarden,communitycentreandtheparking spacesthatcomewithitwillberetained.

The50mby52marealocatedontheSouth-Westcorneroftheplotwillbeusedfortheconstructionoftworowsofterracedhouses consistingof1-Bedroomflatsand individualduplex2-Bedroomhouse.

Areacalculations

Savecirculationspaces

Canaccommodatemorenumberofunitswith1500m2,ifitisa housingscheme.

Orientation&Ventilation

Inanapartment,lotofspaceswithin1500m2islostascirculation spaces.Whereashousingschemewillhaveunitsonlyinthewhole 1500m2.

Toavoidelevators

Totakeadvantagesofthesouthexposureofsite.Splittingas2blocks allowssouthexposuretoallbuildings.Whereasinanapartment schemeorientationofsomeoftheunitswillbecompromised. (Single aspectNorthfacingunit).Schemealsoallowsbetterventilation. Dualaspectunits aredifficulttoachieveinapartmetscheme.

Elevatorsincreasestheenergyconsumption.Adoptionofahousing schemehelpsinavoidinglifts,therbyreducingenergyconsumption.

Reducestructuralloads Placemaking

Morenumberoffloorsneedmorestructuralelementsandstronger foundations.Limitingthefloornumberscouldhelpreducestructural loads.

Surroundingbuildingsintheareaaremostlyofresidentialcharacter andbuildingrarelyexceed2floors.Introducingaapartmentblockof 3to4floorsmightbeoutofcontext.

Phasingadvantages

Splittingas2blocksallowshavinggardenforallunits.Socialhousing isknowntobeinflexibleandistraditionallymeantforindividualsor familieswithyoungerkids.Individualrowhousesgivesfamiliesroom togrow.

Initiallyoneblockcouldbeconstructedandtenantscouldmoveinto generateincome.Lessonslearntfromthisblockcouldbeappliedto thenextblock.

NoOvershadowing

Design Strategies

Affordability

SOCIALHOUSINGSTUDY

WhatisSocialHousing?

Socialhomesareprovidedbyhousingassociations(notfor-profitorganisationsthatown,let,andmanagerented housing)oralocalcouncil.Asasocialtenant,yourent yourhomefromthehousingassociationorcouncil,who actaslandlord.

Socialhousingisalsosometimesreferredtoascouncil housing,althoughthesetypesofhomesareslightlydifferentintermsofthetypeoftenancyagreementyousign, andtherightsyouhavetopropertyasaresult.

Theideabehindsocialhousingisthatit: ismoreaffordablethanprivaterenting usuallyprovidesamoresecure,long-termtenancy

Thisgivessocialrentersbetterrights,morecontrolover theirhomes,andthechancetoputdownroots. 17%ofhouseholdsinEnglandliveinsocialhousingasa whole

TypesofRent

SocialRent(SR)

Targetrentsaredeterminedthroughthenationalrentregime.

AffordableRent(AR)

Wheretherenttobepaidbytenantscanbenomorethan 80%ofthemarketvaluefortheproperty.

RenttoBuy(RB)

Whereadiscountofupto20%ofallmarketrentisappliedforasinglerentalperiodbetween6monthsand5 years.Duringandafterthatperiod,thetenantisoffered firstchancetopurchasetheproperty(eithersharedownershiporoutright)atfullmarketvalue.

HowSocialHousingWorks

Affordability

Socialhomesaretheonlytypeofhousingwhererents arelinkedtolocalincomes,makingthesethemostaffordablehomesinmostareasacrossthecountry.

Rentsforsocialhomesaresignificantlylowerthan privaterents.Rentincreasesarealsolimitedbythegovernment,whichmeanshomesshouldstayaffordable long-termsopeoplearen’tpricedoutoftheircommunitiesbyrisingrents.

Whilethewaysocialrentsaresetisn’tperfect,webelievetheyshouldalwaysbeaffordabletolocalpeople,includingpeopleonlowincomes.

Quality-controlled

Onaverage,socialhomesaremorelikelytomeetthe standardfor‘decent’housing.Theyarebetterinsulated, moreenergyefficient,andmorelikelytohaveworking smokealarmsthanothertypesofhousing.

Overtheyears,investmentinmaintainingandimprovinghomeshasbeenpatchy,andsocialhousingtodayis farfromperfect.That’swhywewillkeepfightinguntil thecountryhasenoughdecenthomesforall.

HouseholdComposition

Stability

Peopleinsocialhousingusuallyhavesecuretenancies,givingthemmuchgreater protectionfromevictionandenhancedrightscomparedtothoserenting privately.Thismeansfamiliescanputdownroots,planforthefutureandmake theirhouseahome.

Asocialhomecanprovidethefoundationpeopleneedtogetoninlife.While somerecentgovernmentshavetakenstepstoreducethesecurityofsocialtenancies,Shelterwillcontinuetofightforallrenterstohavethesecuritytheyneed.

It’sthereforpeoplewhoneedit

Socialhousingshouldbethereforanyonewhoneedsit.Atpresent,thelawstates whoisentitledtosocialhousing,andshouldgetpreferenceonthewaitinglist. Butcouncilshavelotsofflexibilityonwhoqualifieslocallyandsociallandlords canrefusetolettopeopleiftheychooseto.

Thereareoveramillionhouseholdscurrentlyonsocialhousingwaitinglistsin England.Unfortunately,thecurrentchronicshortageofsocialhomesmeans therearen'tevenenoughforpeoplewhourgentlyneedit,suchasstreethomeless peopleandhomelessfamilies.

Webelievethatgood-qualitysocialhousingshouldbethereforanyonewho needsit,includinghomelessfamiliesandindividuals,strugglingprivaterenters, andotherswhocan’tfindasuitablehome.

Source: https://england.shelter.org.uk/support_us/campaigns/what_is_social_housing

StatisticalRelease:SocialHousingLettings:ApriltoSeptember2020,EnglandMinistryofHousing,communities&LocalGovernment

FLOORPLANS-OPTIONAPPRAISAL IDENTIFICATION-BESTORIENTATIONANDFORM

Basedontheanalysisfromthestudyonsocialhousing,itwasidentifiedthatthehighestnumberofneedy populationisconstitutedbysingleadults,followedbysingleadultandchildren,couples,coupleand children.Henceitwasdecidedtoinclude,studio,1bedroomand2bedroomunitsinthisdevelopment.

theimages.Simulationswererunforeachoftheseoptions.Basedonthefiguresfromthese simulations,finallayoutwaschosenanddevelopedfurther.DefaulttemplatesinDesign Builderwereusedforsimulations

Tostartwiththemostenergyefficientlayouts,fewoptionsofthefloorplansweremadetoidentifythebest formandorientations.2bedroomswillcomprisethemaximumareainthedevelopmentandhencethestudy beganbyanalyzingvariouspossibleoptionsfor2bedrooms.Thefloorplanswerecategorizedasshownin

NarrowHorizontal

Square

Squarelayouts.Equalexposuretoall sides.Bufferspacesalignedtonorthin oneoptionandtosideinotheroption.

NB:Floorplansshowninthisstudyarenotfinaloptionsandisjustamodifiedversionsofthe zoning.Theyweresolelydevelopedforanalyticalpurposes. Longsideexposedtosouthandnorth.Bufferspacesallignedtonorthin1optionandoneithersidesinnextoption.

NarrowVertical

Intheseoptions,theshortersidesareexposedtonorthandsouth.In oneoptionthezonesaredividedbypartitionsandintheotheran openlayoutisfollowedtoanalyzewhichoftheseperformsbetter.

CourtyardOption

Thisoptionconsiderstheeffectofhavingcourtyardinthis climate.Courtyardisintroducedinbetween2narrowvertical unitstoincreaseventilation.

FLOORPLANS-OPTIONAPPRAISAL

FLOORPLANS-OPTIONAPPRAISAL

FloorPlan-Type2a FloorPlan-Type2b

FLOORPLANS-OPTIONAPPRAISAL

FloorPlan-Type3a FloorPlan-Type3b

FLOORPLANS-OPTIONAPPRAISAL

FLOORPLANS-OPTIONAPPRAISAL

TOTALENERGY(KWh/M2)

WITHCOOLINGOFF(KWh/M2)

COOLINGENERGY

Bldg1a 69.96 2.86 72.82 2.06 74.88 -0.61 74.27 Bldg1a 55.78 0.07 55.85 0.04 55.89 -1.26 54.63 Bldg1a 14.18 16.97 18.99 19.64

Bldg1b 71.63 3.32 74.95 2.15 77.1 -0.68 76.42 Bldg1b 55.48 0.2 55.68 -0.11 55.57 -1.46 54.11 Bldg1b 16.15 19.27 21.53 22.31

Bldg1c 72.24 -1.42 70.82 2.15 72.97 0 72.97 Bldg1c 52.85 1.45 54.3 -0.04 54.26 0 54.26 Bldg1c 19.39 16.52 18.71 18.71

Bldg2a 66.97 2.27 69.24 1.21 70.45 -1.14 69.31 Bldg2a 58.58 0.23 58.81 -0.24 58.57 -1.64 56.93 Bldg2a 8.39 10.43 11.88 12.38

Bldg2b 75.26 2.06 77.32 1.05 78.37 -0.86 77.51 Bldg2b 67.39 0.27 67.66 -0.27 67.39 -1.3 66.09 Bldg2b 7.87 9.66 10.98 11.42

Bldg3a 65.95 2.44 68.39 1.68 70.07 -0.9 69.17 Bldg3a 54.09 0.12 54.21 -0.04 54.17 -1.32 52.85 Bldg3a 11.86 14.18 15.9 16.32

Bldg3b 65.95 1.55 67.5 1.41 68.91 -0.98 67.93 Bldg3b 54.82 0.19 55.01 -0.17 54.84 -1.46 53.38 Bldg3b 11.13 12.49 14.07 14.55

Bldg4 69.62 1.14 70.76 0.39 71.15 -1.43 69.72 Bldg4 67.21 -0.1 67.11 -0.68 66.43 -1.59 64.84 Bldg4 2.41 3.65 4.72 4.88

Thetableaboveshowsthesummaryofsimulationsrunforallthefloorplansshownintheprevious pages.GenerallyManchesterisaheatingdominatedregionandhouseshaveonlyheatingfacilities. Currentlyduetoclimatechangebuildingsmayneedairconditioninginfuture.Hence,Annual

energy(Kwh/m2/yr),AnnualenergyifthebuildingisnotcooledandEnergyrequiredforcooling wasseparatelynotedtomakeanalysisfromthesevalues.Theresultsoftheanalysisaregiveninthe followingpages

FLOORPLANS-OPTIONAPPRAISAL

AnnualEnergy-Whenbuildingisnotcooled

ENERGY(COOLINGEXCLUDED)(KWh/M2)

Current Diff

Bldg1c 52.85 1.45 54.3 -0.04 54.26 0 54.26

Bldg3a 54.09 0.12 54.21 -0.04 54.17 -1.32 52.85

Bldg3b 54.82 0.19 55.01 -0.17 54.84 -1.46 53.38

Bldg1b 55.48 0.2 55.68 -0.11 55.57 -1.46 54.11

Bldg1a 55.78 0.07 55.85 0.04 55.89 -1.26 54.63

Bldg2a 58.58 0.23 58.81 -0.24 58.57 -1.64 56.93

Bldg4 67.21 -0.1 67.11 -0.68 66.43 -1.59 64.84

Bldg2b 67.39 0.27 67.66 -0.27 67.39 -1.3 66.09

Theresultsshowstheannualenergyrequiredforthe buildingwhencoolingloadsarenotconsidered.So, generallywhichmeansthattheseresultscontainthe energyrequiredforheating,lightingandothers.Itis notedthat,inallthebuildings,exceptinbuilding1cand 4,thereisslightincreaseintheenergyby2030andthen slightlyreducesby2050andthenagainreducesby2080. Thisshowsthatbuildingsneedlessenergyforheatingas thetemperaturerisesupandmanymorehourswillfall undercomfortzone.

Itisfoundthatbuilding1cwithmoresouthexposure performsbest,thensquareshapedonesfollowedby otherlongnarrowhorizontallayouts.Narrowvertical onesdoesnotperformwellintermsofheating. Courtyardoptionandplanwithopenlayoutperforms worstintermsofheating.Thisshowsthatmore compartmentalizedplansperformsbetterinefficiently heatingthespaces.

Forbuilding4(courtyardoption),itcanbeseenthatthe

temperatureconsistentlyreducesoveryears.Thisshows thattheeffectivenessofwellventilatedbuildingsin reducingtheoverallenergywhenthetemperaturerises up.

Adifferenttrendformotherbuildingsisshownby building1c.Forthisbuilding,thetemperaturereduces farmorethanotherbuildings,in2030andthenrisesby 2050andagainslightlyincreasesby2080.Thisbuilding hasmoresouthexposureandhencethebuildinggets overheatedandsotheincreaseoftheenergiesin2050 and2080isjustified.However,thereasonforthe buildingtobecomelotmorecoolerthanallother buildingswasnotunderstood.Theonlyprobablereason assumedwasthepresenceoflongnorthfacingwindows inthecorridorinfirstfloor,whichmakesthisspace coolerandfurtherhelpstokeepthewholebuildingcool. Thedifferenceintrendofbuilding1ccanbeclearlyseen fromthegraphonleftsidethatonlyplotsthedifferences inenergyoveryears.

FLOORPLANS-OPTIONAPPRAISAL

Energyrequiredtocoolthebuilding

COOLINGENERGY

Current 2030 2050 2080

Bldg4 2.41 3.65 4.72 4.88

Bldg2b 7.87 9.66 10.98 11.42

Bldg2a 8.39 10.43 11.88 12.38

Bldg3b 11.13 12.49 14.07 14.55

Bldg3a 11.86 14.18 15.9 16.32

Bldg1a 14.18 16.97 18.99 19.64

Bldg1b 16.15 19.27 21.53 22.31

Bldg1c 19.39 16.52 18.71 18.71

Generallyitcanbeseenthattheoptionsthatperformedbestinheatingthebuilding,performs worstincoolingthebuilding.Option4(Courtyard)performsthebestofall.Thelongnarrow verticalbuildingsalsoneedverylessenergytocoolthebuilding.Outofthattheonewithopen partitionsperformsbetterthantheoneswithclosedpartitions.Squareshapedlayoutscomesinthe middle.Narrowhorizontalonesperformstheworstintermsofcoolingenergy.

Thedifferenceinthetrendofbuilding1ccanbeclearlyobservedfromthegraphabove.Itcanbe notedthatthecoolingdemandofallthebuildingsincreasesoveryears.Rateofincreaseismoretill 2050andthenthereisareductionintherateofincrease.

Cooling Energy

Fromtheheatingandcoolingenergygraphs,itcanbenotedthatthecompactand compartmentalizedplanningisbestforretainingheatinsidebuilding,whereasforcooling,more openplanlayoutsarepreferred.Manchesterisaheatingdominatedregion,socompact compartmentalizedlayoutsweretraditionallyadoptedintheregion.However,duetotheclimate changethetemperaturesarerisingupandthispointsouttotheneedofconsideringcooling energiesaswell.Thebuildingsthatwerehistoricallydesignedgivingprominencetoheatingenergy nowneedtoconsiderreducingcoolingloadsaswell.

Soalayoutthatcanbalancebothheatingandcoolingenergyispreferred.

FLOORPLANS-OPTIONAPPRAISAL

Annualenergy

TOTALENERGY(KWh/M2)

WITHCOOLINGOFF(KWh/M2)

COOLINGENERGY

Bldg3b 65.95 1.55 67.5 1.41 68.91 -0.98 67.93 Bldg3b 54.82 0.19 55.01 -0.17 54.84 -1.46 53.38 Bldg3b 11.13 12.49 14.07 14.55

Bldg3a 65.95 2.44 68.39 1.68 70.07 -0.9 69.17 Bldg3a 54.09 0.12 54.21 -0.04 54.17 -1.32 52.85 Bldg3a 11.86 14.18 15.9 16.32

Bldg2a 66.97 2.27 69.24 1.21 70.45 -1.14 69.31 Bldg2a 58.58 0.23 58.81 -0.24 58.57 -1.64 56.93 Bldg2a 8.39 10.43 11.88 12.38

Bldg4 69.62 1.14 70.76 0.39 71.15 -1.43 69.72 Bldg4 67.21 -0.1 67.11 -0.68 66.43 -1.59 64.84 Bldg4 2.41 3.65 4.72 4.88

Bldg1a 69.96 2.86 72.82 2.06 74.88 -0.61 74.27 Bldg1a 55.78 0.07 55.85 0.04 55.89 -1.26 54.63 Bldg1a 14.18 16.97 18.99 19.64

Bldg1b 71.63 3.32 74.95 2.15 77.1 -0.68 76.42 Bldg1b 55.48 0.2 55.68 -0.11 55.57 -1.46 54.11 Bldg1b 16.15 19.27 21.53 22.31

Bldg1c 72.24 -1.42 70.82 2.15 72.97 0 72.97 Bldg1c 52.85 1.45 54.3 -0.04 54.26 0 54.26 Bldg1c 19.39 16.52 18.71 18.71

Bldg2b 75.26 2.06 77.32 1.05 78.37 -0.86 77.51 Bldg2b 67.39 0.27 67.66 -0.27 67.39 -1.3 66.09 Bldg2b 7.87 9.66 10.98 11.42

Sortingthebuildingsaccordingtotheannualenergy consumptioninallyearsshowsthatbuilding3b performsthebestofall.Thesquareshapedplanswere foundtobeperformingbestannually.Narrow horizontaloneswerenotfoundtobeperformingbest annuallythoughtheyperformsbetterintermsofheating

Notthebestperformersintheheatingandcooling energiesbecomesthebestperformersannually.A balancedplanperformsbetterannually.Squareshape thathasequalexposuretoalldirections,withample exposuretosouthandnorth,withbufferspacesinthe sidesperformsbetter.Thisalsoshowsthataligningthe bufferspacesliketoilets,storeetccompletelytothe northsidemaynotbegoodinacoldtemperatezonelike Manchesterthoughitmayworkwellwithextremecold climates.Followingaresummaryofanalysis.

•Openplanneedslessenergytocoolthehouse,but comparativelyneedshighenergytoheataswell.

•Buildingswithlessexposuretonorthandsouthrequires lessenergytocool.

•Buildingssquareshape–requiresoptimumenergyfor cooling

•Buildingswithlongexposuretosouthandnorthneeds highenergytocool.

•Buildingwithcourtrequireshighenergytocool–(check)

•Theenergyrequiredforcoolingslightlyincreasesover years

•Squareplansandplanswithmoresouthernexposure needtheleastenergytoheatthehouse

•Planwithcourtrequireshighenergytoheatthehouse

•Narrowplanwithlessexposuretonorthandsouth requireshighenergytoheatthehouse

•Openplanrequireshighestenergytoheat

•Theenergyrequiredforheatingslightlydecreasesover years

FLOORPLANS

2BEDROOM,1BEDROOM,STUDIO

Planning Studios

Basedonanalysisfromthestudyon socialhousing,energyanalysisfor orientationandformstudy,itwas decidedthatschemewillhave2blocks andeachblockwillhave4unitsof2 bedrooms,4unitsof1bedroomand4 unitsofstudiorooms.Thatiswhythe projectisnamedas444byOne Manchester.

2Bedroom

Aspertheinferencesfromenergy analysis,squarelayoutwaschosenfor2 bedroomunits.Entrytotheunitisfrom northside.Afoyerspacehasbeengiven asbufferspace.Allthebufferspaceslike foyer,stairwell,storeroomandtoilethas beenalignedtotheside.Inbetween livingdiningandkitchen,solidsliding foldingdoorshavebeenprovided.In winterdoorscanbekeptclosedto preventairflowandandinsummerthese doorscanbekeptopentoallowcross ventilation.Apocketdoorhasbeen providedatthestairarea.Inwinterthis canbeclosedwhereasinsummer,itcan bekeptopen.Allthegardensaresouth facingandcanbeaccessedfromdining area.

2studiounitseachareplacedon eithersidesof2bedrooms. Everystudiounitsgetsaccessto privatesouthfacinggardens. Entrytotheblockisfromnorth side.Thereiscommonstairway thatleadstofirstandsecond floors.

1Bedroom

Every1bedroomsunitshavea balconyastheseunitsdon’t haveaccesstoprivategardens.2 unitsof1bedroomunitsare placesoneithersidesof2 bedroomunits,abovestudio units.

FLOORPLANS

FLOORPLANS

2BEDROOM-CONVERTIBLEOPTIONS

Theproposedschemeconsistoffour2bedroomunits,four1-bedroomunitsand fourstudiounits.However,forthefamilies livingin2bedrooms,theymightneed separateroomsforkidswhentheygrowup. Inthatcaseitwon’tbeaffordableforthem tomovetoanewplace.So,considering socialsustainabilityinlongterm,alternate convertiblelayoutsof2bedroomsarealso proposed.Intheselayouts,itiseasierfor thetenantstoconverttheexisting2 bedroomto3bedroomwithminimal interventions(addingpartitions). Developercanchoosebetweenthe3 optionsof2bedroomsavailable.

Option1

Option2

ELEVATIONS

open partitions

AftergivingrightUvaluesforthe fabric,glazingandchoosing appropriatelightingandhvac system,theunitswereanalyzed inviduallytoseehowitperformed andhowcantheybefurther improved.

Theeffectofseasonalopenand closedpartitions,wereclearly understoodfromtheprevious energyanalysis.However,for furthersimulations,thebuilding anhaveitherclosedoropen partition.Sosimulationswere donetoseewhichofthese performedbetterannually.Itwas foundthatannuallyopen partitionsperformedbetter.

Foldabledoorscanbekeptclosed duringthewinterperiodtoreduce theheatingenergy,andthose doorscanbekeptopentofoster crossventillationduringthe summerperiods.Thiswillhelpin reducingthecoolingloads.

Overallperformance

Annual Performance

ENERGYANALYSIS-OVERHEATING

Overheating Groundfloor Firstfloor

OneManchesterfollowsCIBSEguidance,which statesthatoverheatingisdeemedtooccur:

•Forlivingareas,ifmorethan1%oftheoccupied hoursareover28ºC.

•Forbedrooms,ifmorethan1%oftheoccupied hoursareoveratemperatureof26ºC.

•Thebestpracticesummerindoorcomfort temperatureis25ºC.

Hencethetemperaturesofallthesezoneswere analyzedtoseeifthereisoverheating.Zoneswith overheatingneedsfurtherchangesindesignto limitthenumberofoverheatedhours

Technicallyasthereisnohoursthatgoesabove28deginanyof theyears,thisspacehasnoriskofoverheating.However,more than5%ofhoursgoesabove25degandhencedesigndetails shouldtrytolimitthesehours.

Asopenpartitionsare useddiningkitchenand livingroom,Design Buildertreatsthesezones asmergedzones.Hence resultsaresameforall areas.

Riskassessmentswere doneforlivingareasinthe groundfloorandSouth andNorthbedroomsin firstfloor.Percentageof hoursabovethethreshold werecalculatedtoidentify overheatedspaces

TEMPERATURE

First

South Bedroom

FF North Bedroom

Asmorethan1%ofthehoursgoesabove25,26and28degreesin alltheyears,thisspaceisattheriskofoverheating.Window sizesmustbeoptimizedandshadingtobeintroducedtobring thetemperaturesintocomfortband.

Asthenumberofoverheatedhoursareverylow,thiszoneisnot undertheriskofoverheatingandhencenofurtherinterventions needtobedone.

2BEDROOMSUNITS

AFTER

Inordertolimitthenumberofoverheatedhoursinsidethebuilding,severalwindowoptionsweretried. Differentshapesandsizesweretriedoutduringsimulationstoidentifywhichofthemperformsbetter. Separatesimulationswererunforgroundfloorandfirstfloorwindows.Alltheoptionstriedareshownin theleftsideandthefinalizedoptionisshownabove.

CalculationofShading

Asperthechartsinclimateconsultant,thereno mucheffectforoverhangsinthecurrentclimate. However,asyearspassbytherearemore uncomfortablehoursandhencetheshadingbecomes important.Theeffectofshadingismoreinthefuture years.Whencalculatingthedegreesasperclimate consultant,itisseenthatthehorizontalanglevaries between48-55degrees.Whencalculatingthe overhangsbasedontheseangles,itvariesbetween11.8m.Thisdistanceisdifficulttoshade.

EffectofOverhang

Effect of overhang

Twooptionsweretried.Only withoverhangandwith overhangsandfins.Simulations weredonewithdifferentlengths ofoverhang.Whenthelengthof overhangsincreasesbeyonda limit,iteffectsdaylight.Hence 0.7moverhangwhichkeepsa balancebetweenenergieswas chosen.

Fromthegraphsitisclear that,thereisreductioninthe overallenergydemandwith theintroductionofoverhangs. Plottingthedifferencesit makesoveryearsshowsthat overhangsbecomemore effectiveinthefutureclimate scenarios.Howeverthe reductionenergyinenergyis onlyasmallfigure.

Theeffectofoverhangsinthe overallenergyisanalyzed.But themostimportantfunction isprovidecomfort temperaturesinsidebuilding. So,theeffectofoverhangson thenumberofoverheated hoursneedtobequantifiedto assessitscompleteeffect.

Withoverhangandfins

Ground floor Overhangs

Graphsclearlydemonstratestheeffectof overhang.Bothingroundandfirstfloorthe numberofoverheatedhoursdrasticallyreduces whenoverhangsareintroduced.Ingroundfloor, withtheintroductionofoverhangsmorehours fallwithincomfortableband.Inthefirstfloor, the%ofhoursmorethan26degreeisgreater than1%inallthescenario.Withthe

introductionofoverhangs,thepercentageof hoursabove26degreecanbeboughtdownin currentand2030scenario.However,thereare stilloverheatingproblemsin2050and2080.The percentageofhoursabove28degreeshavebeen effectivelyreducedbyoverhangs.Furthersteps needtobetakentoavoidoverheatingthatwill probablyoccurin2050and2080.

First floor Overhangs

Thoughclimateconsultant chartsdoesnotshowthefins tobereallyeffectiveinthis sccenario,tolimitthenumber ofoverheatedhours,finswere alsoaddedalongwith overhang.Ingroundfloorsome morehourscomesunder comfortableband.Whereasin firstfloor,the%ofhoursabove 26degreecomesdownbelow 1%inallthescenarioswiththe additionoffins.Soboth overhangsandfinstogether helpstoreduceoverheated hoursofthisunit.

2BEDROOMSUNITS

STUDIOUNITS

Eastsidestudios

Thebuildingis6degrees rotatedfromcardinalsouth directionandhencethe southeastcornergetsalot exposedtosun.Hencethe chancesofoverheatingare moreinthiszone.Climate consultantchartsbelow showsthathorizontal overhangsthoughnotfully effectivecancutfewofthe overheatedhours. However,operablelouvers canbemoreeffectiveineast side.Allthewindow shapesandsizesof windowstriedoutforeach sidesareshowninthe imagesbelow.

Severalwindowoptionsweresimulatedtoseewhichofthem performsbest.Initialdesignhadwindowsonbothsouthand eastfacades.However,therewerelotofoverheatedhours insidetheroomsandhenceaspartofreducingoverheatedhours onlykitchenwindowintheeastfacadecouldberetained.Final optionofthewindowsareshownabove

CalculationofShading

STUDIOUNITS

Westsidestudios

Asthebuildingis6degrees rotatedfromcardinalsouth direction,Westsideismore orientedtowardsnorth.So thezonesinthisside performsmuchbetterthan southeastside.Which allowstohavesome windowsinthewestside. Though1bedroomunits couldhavewindowsonthis side,instudiounit,adding windowsleadsto overheatingandhenceitwas avoided.Theoptionstried onwestsideisshownbelow. Theelevationtosouthside wasmaintainedsameaseast sideforsymmetry.

Finaloptionofthewindowsforthewestsideareshownabove. Climateconsultantchartsbelowshowsthatthesewindows cannotbeeffectivelyshadedbyhorizontaloverhangssolouvers arethebesttoshadethesewindows.

CalculationofShading

Eachzonesinthe1bedroomunitswereanalyzedtoseethe spacesthatareoverheated.Graphsshowstheoverheating analysisdoneforeachspaces.Thenumberofhoursthatgoes

abovetargettemperaturesandthe%oftheexceededhours werecalculated.Basedontheseresultswindowwere optimizedforthisunit.

Asthegraphsclearly shows,onlybedroomsin this1bedroomunithave overheatingproblems. Thoughthisbedroom doesn'thaveany overheatingissuesinthe currentclimate,more than1percentageof hoursgoesabove26 degreesfrom2030 onwards.Sothe openingsandshadings mustbeadjustedto reducethenumberof overheatedhours.

Nootherzonesinthis unithaveoverheating issues.Thereareno hoursthatgoesabove26 degreesinthesezones. However,therearefew hoursabove25degrees. Thesecanbereducedby introducingshading.

East 1BHK FF Bedroom

Asthegraphsclearlyshows,aftermaking adjustmentstothewindowsizesand introducingoverhangs,thenumberof overheatedhoursinthebedroomhas drasticallyreduced.Thepercentageofhours thatgoesabove26degreescomesbelow1% inalltheyearsandtherearenohoursthat goesabove28degrees.However,when windowswereoptimizedtoaddress overheatingissues,ithasleadtoaslight increaseintheoverallenergyofthebuilding. Thisisbecausewhenwindowsizesare reducedandshadingisintroduced,itleads toslightincreaseinthelightingenergyand heatingenergies.Whenwindowsizesare reducedbeyondacertainthreshold,itwill leadtoincreaseinenergy.Henceitis essentialtokeepabalancebetweenthem.

East 1 BHK FF Bedroom

Energy comparison

West 1BHK

Bedroom

OvershadowingofGardens

fectondaylightandsunlighttoneighbouringproper-

lightbytheadjacentbuildingaccordingtotheimage

dowwasusedasthereferencepointforthetest.Ifthe

likelytobeasubstantialeffectondaylightandsun-

HEATINGANDHOTWATERSYSTEM-OPTIONAPPRAISAL GSHP,ASHPANDCHPCOMPARISON

GroundSourceHeatPump AirSourceHeatPump CHP(CombinedHeat&Power)

GSHPsabsorbheatfromthegroundthroughpipeswithanantifreezeliquidburiedundergroundwhichisthencompressed andusedtoheatindoor.Thesystemtransferstheheatabsorbed towaterwhichisdistributedthroughunderfloorheating.

WhenlandisavailableGSHPsystemsarelaidinhorizontal trenchesthatareapproximately1-2metresdeep.Verticalboreholesareamoreexpensivealternativewhereholesaredugupto around150m.

Advantages

Providesheatingandhotwater

LongerlifespanthanASHPs

Easytomaintain potentialincomethroughtheUKgovernment’sRenewable HeatIncentive(RHI)

Disadvantages

Highsetupcost

Requireslotsofspace

Heatproduceddependsonthedensityandtypeofsoilandbedrock

ASHPsabsorbheatfromoutsideairwhichisthencompressed andusedtoheatindoorspacesandwater.

TherearetwotypesofASHPsystems,AirtoAirandAirtoWater.AirtoAirprovideswarmairandventilationwhichiscirculatedbyfansthroughducts.AirtoWatersystemstransferthe heatabsorbedtowater,whichissuitedtounderfloorheating andradiators.

Advantages

Providesheatingandhotwater

Lowersfuelbills

Easytomaintain potentialincomethroughtheUKgovernment’sRenewable HeatIncentive(RHI)

EnergyEfficient

Disadvantages

Canonlybeusedalongsideanotherheatingsysteminmost buildings

Canbenoisy

CHPisanenergyefficientmethodandmakesuseoffueltogenerateelectricityandheat.Electricityisproducedonsiteanthe excessheatgeneratedasaresultofburningfuelisusedtoheat buildingsandtoprovidehotwater.

Advantages

Providesheatingandhotwaterinadditiontoelectricity

Reducesenergycost

Reducedemissions

Energysecurity

Reducestransmissionlossfromthegrid

Makesuseofexcessheatproducedasaby-productofelectricity production

Disadvantages

Highsetupcost

Takesnon-renewablefueltorun

Suitableforlargecommunities

Needsconstantsupplyoffuel

Seasonal

Wallsintheliving spacescanbecollapsed duringthesummerto promoteairflow

WaterManagement

RainwaterCollection

Theslopingroofswillbeconstructedusingclaystep tileswhichwillhelpchannelrainwaterintopipes. Rainwaterwillbestoredintanksbelowgroundand willbeusedforgardeningandflushingtoilets.

Greywater

WasteWaterHeatRecovery

HeatfromgreywaterwillberecoveredviaanEcoDrain whichtransfersheatenergyfromthehotshowerwater totheincomingfreshwatersupply.

WaterEfficientFittings

Shading

Dual-flushtoiletsandfaucetaeratorswillbefittedtoreducewater

HeatingCooling&HotWater

AirSourceHeatPumpswillbeusedtoprovideheating andhotwatertothecommunity.Theyalsocanprovide coolinginthesummer.AirSourceHeatPumpsareareliablesourceofheatwhichworkswellintheUKclimate.Thecostofinstallationislowercomparedto GroundSourceHeatPumpsandCHPplants.Usually, AirSourceHeatPumpsareusedtosupplementanexistingheatingsystem.However,sincethebuildingsaredesignedtoachievepassivhausstandards,verylessheatingwillberequiredforwhichAirSourceHeatPumps aremorethansufficient.

Ventilation

MechanicalVentilationwithHeatRecovery

AnMVHRsystemfiltersairthatentersabuildingwhile recoveringheatfromstaleairthatleavesthebuilding.It helpsmaintaintheindoorairtemperatureandisanessentialsystemusedinpassivehouses.Features:

•Recoversupto95%ofheatthatisnormallylost, helpsreduceheatingcost.

•Moiststaleairisextractedfromkitchensandbathrooms,lowershumidityandcondensation.

•Improvesairquality,createshealthylivingenvironment.

Electricity

SolarPanelswillbeplacedontheslopedroofandwill besupplementedbyelectricityfromthegridwhennecessary.Theelectricityproducedwillbeusedtopower homesandcars.Electriccarchargingstationswillbe placedintheparkinglots.

TripleGlazedTimber

FrameAluminium

Panel(SlopingComponent)

Panel(FlatComponent)

1.VinylFloorFinish

Panels

CONSTRUCTIONMATERIALS

StructurallyInsulatedPanels(SIPs)

Structuralinsulatedpanels(SIPs)areahigh-performancebuilding systemforresidentialandlightcommercialconstruction.Thepanels consistofaninsulatingfoamcoresandwichedbetweentwostructuralfacings,typicallyorientedstrandboard(OSB).SIPsaremanufacturedunderfactorycontrolledconditionsandcanbefabricatedto fitnearlyanybuildingdesign.Theresultisabuildingsystemthatis extremelystrong,energy-efficientandcost-effective.

ThermalPerformance

Onceinstalled,SIPpanelsdeliverunrivaledinsulationandairtightness,whichreducesenergycostsoverthebuilding’slifetime.SIPsare knowntobeabout50%moreenergy-efficientthantraditionaltimber framing.ASIPbuildingenvelopehasminimalthermalbridgingand deliversexcellentairtightness,whichlendsitselfideallytoLEEDand net-zero-readybuildingstandards.

IndoorAirQuality

ASIPbuildingallowsbettercontroloverindoorairqualitybecause theairtightbuildingenvelopelimitsincomingairtocontrolledventilationwhichfiltersoutcontaminantsandallergens.TheSIPenvelopedoesn’thavethevoidsorthermalbridgingofconventionalframingthatcancausecondensationleadingtopotentiallyhazardous mold,mildeworrot.

Sustainability

SIPsarehighlyenergy-efficientandthereforecontributepositivelyto theenvironmentbyreducingCO2levels.Theyalsousesignificantly lessenergyduringthemanufacturingprocesscomparedtotraditionalconstructionmethodsandhavelowerembodiedenergythan traditionalconstructionmaterials,suchassteel,concreteandmasonry.

ConstructionProcesses

SIPwallsandroofsaredesignedandpreciselymanufacturedoffsite. Thisallowsthebuildingtobeassembledonsitequicklyandmade watertightinamatterofdays.Thisreducescostssuchasproject management,scaffolding,framinglaborandmuchmore.SIPpanels reducejobsitelaborneedsby55%.

BrickCladding

BrickisthemostcommonlyusedexternalcladdingmaterialusedintheUK andisproducedlocallycountrywide.It createsasenseoffamiliarityaandhomelikewarmthwhichisanimportantconsiderationforasocialhousingcommunity.

ClayBricksareweatherproof,fireresistant,longlasting,andareeasytomaintain.Theyhaveagenerallylowembodiedcarbonastheyaremadefom

ClayRoofTiles

ClaytilesareastapleinUKandcan withstandharshclimaticconditions (evenbetterthanconcretetiles).They arealsolonglasting,durable,andare easytoinstall.Theyaremadeusingclay whichisanaturallyoccuringmaterial andhencehavealowembodiedcarbon. Theyarewidelyavailablethroughout theUKandcanbesourcedlocally.

RockWoolInsulation

RockWoolinsulationisusedwithinthe internal,non-loadbearingwallsinthe apartments.Rockwoolismadeusing basaltandsteelslag.Itissustainableand wideleyavailable.Itshighdensitygives italowu-valueandlowerssoundtransmissionsandairflow.Itrepelswater whichmakesitmoldandmildewresistant.Unlikefibreglass,rockwoolinsulationdoesntcauseanyskinirritation.It isalsoknowntokeeprodentsaway.

ExpandedPolystyreneInsulation

ExpandedPolystyreneInsulation (EPS)comesinrigidboardsthatcanbe applieddirectlyabovetheDPMlayerbelowtheconcreteslab.Itprovidesexcellentthermalinsulationandis exteremelydurableandmoisture reistant.ESPcosteffectiveandefficent. Itisalsoeasytotransportaandishighly versatile.

LIFECYCLEASSESSMENTFOR1ROW

Theembodiedcarbonofonerowofhousingconsistingof4StudioFlats,4OneBedroomFlatsand 4TwoBedroomFlatsis456TonsofCO2e.

Therowhasagrossinternalfloorareaof840m2 andisbuiltusingStructurallyInsulatedPanelsandisexternallycladwithclaybricks.ThefoundationisinsulatedwithExpandedPolystyreneInsulationandadditionalglasswoolinsulationis usedtoinsulatetheatticspaces.AllmaterialsusedaregenericandaremanufacturedintheUK whichsignificantlyreducesembodiedcarbonofproductionandtransportation. TherowofhousingwillbeconstructedusingStructruallyInsulatedPanels(SIPs)withaBrick cladding.Thestructureis3floorshighandhasaslopingroofwithanatticspace.

GWP:GlobaWarmingPotential

AP:Acidification

EP:Eutrophication

ODP:OzoneLayerDepletion

POCP:FormationofOzoneofLowerAtmosphere

TUOE:TotalUseofPrimaryEn

Bio-CO2:biogenicCarbonStorage

Acidification

Acidificationoccurswhensulphur,nitrogen, andcarboncompoundscontaminatelandand oceanscausingthemtoacidify.

Eutrophication

Eutrophicationistheprocessbywhichanentirebodyofwater,orpartsofit,becomesprogressivelyenrichedwithmineralsandnutrients,particularlynitrogenandphosphorus.

BiogenicCarbonStorage

Biogeniccarbonisthecarbonthatisstoredin biologicalmaterials,suchasplantsorsoil.UsingmaterialssuchastimberwithhighBiogeniccarbonstoragehelpskeepcarbonoutof theatmosphere.

Thelifecycleofrawmaterialsusedandtheoperationalenergyhavethehighestimpacton theenvironment.ThetimberusedinStructurallyInsulatedPanelscontributepositivelyto Biogenicstorageofcarbon.Therearemany otheraspectstothisdesignwhichwillnegativelycontributetotheenvironmentthrough acidification,eutrophication,ozonelayerdepletion,andincreaseglobalwarming.

Theprimarybuildingmaterials usedinthisbuildinghasthe highestamountofembodied carbon.Thebuildingsmakeuse ofStructurallyInsulatedPanels (SIPs)whichwerenotavailable intheOneClickLCAcatalogue.SIPspanelsconsistofRigidpolyurethaneinsulationsandwiched betweenorientedstrandboards.Sincethesecomponentswerecalculatedindividually,thereisa chancetheydisplayhigherembodiedcarbonvaluesthanactualSIPspanels.

OtherthanthePolyurathaneinsulation,thebrick facade,rooftiles,andEPSinsulationusedinthe foundationseemtohavehighembodiedcarbon values.

Theapartmentsarepoweredfullybyelectricity andhavealowoperationalenergyconsumptionof 20kWhpersquaremeterperannum.Thesolar panelsrequiredtopowerthebuildingwascalculatedinthenextstageanditwasfoundthatthe kwp(kiloWattPotential)forpanelsexceededthe requiredamountwhichpotentiallymakestherow carbonnegative

EMBODIEDCARBON&LIFECYCLEASSESSMENT

LIFECYCLEASSESSMENTFOR1ROW

Theembodiedcarbonofthebuildingcanbesignificantlyreducedbyreplacingsomematerialswith oneswithalowerlifecycleemissions.

ExtrudedPolystyreneInsulation(EPSinsulation canbereplacedwithExpandedPolystyreneInsulation(XPS)insulation;theVinylFlooringcanbe replacedwithCeramictiles;andnaturalstone couldbeusedinsteadofbricktocladtheexterior.

Additionally,alltheelectrictytopowertherow couldbeoffsetbyinstallingsolarpanelswhich wouldbeconnectedtothegridinordertoensure areliablesupplyofelectricty.

Theserowhousesaredesignedtobereplicable. Onerowofhousingcanbebuiltandtestedbefore theconstructionforthesecondrowcanbegin. Furtherchangesonmaterialsandbuildingtechniquescanbemadeafterthepost-construction evaluationtoimprovethelifecyclecarbonandthe overallperformanceoftherowofapartments.

EPSvsXPS

EPS:46tons

XPS:31tons

CarbonSavings:15tons

15tons ofcarbonemmissionscanbereducedifthefoundation isinsulatedusingExtrudedPolystyreneInsulation(XPS)insteadofExpandedPolystyreneInsulation(EPS).BothEPSand XPShavegreatthermalpropertieswhichmakesthemsuitable forinsulatinggroundslabsdirectly,XPShasgreatercompressivestrengththanEPSwhichmakesitmoreefficient.XPSalso performsbetterinregionswithawetclimateasithasahigher vapourdiffusionresistancevalue.

VinylFloorvsCeramicTiles

VinylFloor:1.9tons

1.859tons

flooringisreplacedwithceramicfloortileswhichisabetter conductorofheatandismoresuitedtoworkincombination withunderfloorheating.Vinylfloors,althoughcheapandeasy toinstall,arenotentirelydurableandcanemitvolatilecompounds(VOCs).Ceramictilesareaffordable,versatile,andfire resistant.Theyarealsohighlydurableanddonotcauseany harmtothehealthoftheoccupants.

BrickvsNaturalStoneCladding

BrickCladding:69tons

NaturalStone:41tons

CarbonSavings:28tons

28tons ofcarbonemmissionscanbereducediftheexternal claybrickcladdingcanreplacedwithanaturalstonecladding whichhasahighthermalmassandverylowembodiedcarbon. NaturalstonesareavailablewidelythroughouttheUKand havebeenusedinconstructionforcenturies.Theyareweather resistantandoffersimilaradvantagesthatbrickdoes.Itisnaturallyoccuringandtheonlycarboncostinvolvedisthecostof extractionandtransportationwhereasclaybricksneedtofuel tobebaked.

SOLARPANELCALCULATIONS

PERFORMANCEOFGRIDCONNECTEDPVPANELS

Thetypicalwattageofaresidentialsolarpanelperunitisaround300w,thisfigurecouldbemoreorless thanthisvalue.Theannualenergyconsumptionoftheproposedbuildingisestimatedtobe20kwh/ m2/yr.thisvaluetranslatestobeapproximately15,580kwh/yr,consideringthetotalfloorareaof779 sqm.

Fromthetablebelow,itwasestimatedthateachunitinabuildingblockwouldneed2kwp(kilowatt peak)ofsolarPVsystemconsistingof8(250w)panels.

Consequently,acombinedtotalof24kwpofsolarPVsystemconsistingof96(250w)panelswouldbe neededtogenerateelectricityforthe12units,inabuildingblockforaperiodofoneyear.Estimatedannualenergyoutputbycalculationis20,200kwh.

ThisassumptionformsthebasisforthePV(gridconnected)resultspresentedbelow.

SUMMARY

FabricUValues(W/m2.K)

Walls 0.09

Floor Ground 0.08

Intermediate 0.13

Roof 0.08

Windows 0.78(Trippleglazed)

FormFactor Energyconsumption

Thermalenvelope/Heatlossarea(HLA)SQM

Wall Roof Adjoiningwall

North 316.42 137.14

South 316.42 137.14

West 75.67 21.40

East 75.67 21.40

Total 784.18 274.28 42.80

Window-to-wallarearatio

North 16.31

East 1.09

South 25.71

West 4.14

Efficiencymeasures

Airtightness 0.4(m3/h.m2@50Pa)

HLA 1101.26

GrossFloorAreaSqm

Treatedfloor

Floors Area Total 75%Grossfloor

Ground 351.66 778.62 First583.97 351.66

Second 75.30

Form Factor= HLA/TreatedFloorArea 1.89

Formfactoris theratioofsurfaceareathatcanloseheat(thethermalenvelope)tothefloorareathatgetsheated(TFA).Inotherwords,theHeat LossFormFactorisausefulmeasureofthecompactnessofabuilding. Andthemorecompactabuildingis,theeasieritistobeenergyefficient.

TheHeatLossFormFactorisanumbergenerallybetween0.5and5,with alowernumberindicatingamorecompactbuilding.Passivhausbuildings aimtoachieve3orless.Herethebuildinghasaformfactorof1.89which isreallyagoodvalue.

Energyper totalbuilding area(Kwh/m2/ year)

Energyper conditioned buildingarea (Kwh/m2/year)

2bedrooms 19.78 20.48

Eastside

Studio(Total) 26 29.36

Studio1(inner) 29.70 29.70

Studio2(outer) 31.31 31.31

1bedroomFF 21.62 24.71

1bedroomSF 25.71 29.44

Westside

Studio(Total) 26.02 29.38

Studio1(inner) 29.69 29.69

Studio2(outer) 31.33 31.33

1bedroomFF 22.18 25.34

1bedroomSF 25.83 29.58

Thetypicalunitvaluesareasshownabove.However,onoverall simulation,designbuildershowedanannualenergyperformance of17Kwh/m2/yrforthewholeblock.Thevaluesshownabovewere receivedwhenthesimulationsweredoneseperatelyforeachunits.

RENDEREDVIEW

RENDEREDVIEW

CONCLUSIONS

Thisprojectrequiredextensiveresearchandmodellingtodeterminethebestpossiblebuildingsolutionsthatwould helpcreateanenvironmentally,socially,andeconomicallysustainabledesign.Thebuildingisanetzerocarbon (possiblycarbonnegative)andhasalowlifecyclecarbon.Theenergyconsumptionisalsoquitelow,at approximately20kWhperm2perannum.

Thedesignbeganwiththeoptimizationoffloorplansandwindowstoreduceenergyconsumptionbymodelling themonDesignBuilder.Sustainabledesignstrategiesandpassivestrategieswereimplementedtoconsolidatethe design.Thebuildinghasacompactformfactorof1.8andthelowu-values.Thebuildingismostlyheatingdominated andwillbeheatedusingAirSourceHeatPumpsalongwithanMVHRsystem.Duetothehighefficiencyofthefabric andsystems,verylittleenergywillbespentonheatingthebuilding.AirSourceHeatPumpscanalsobeusedfor coolingonhotsummerdays.Thereareotherpassivestrategiesinplacetotackleoverheatingduringthesummer, suchasretractableshadingdevices.TheprojectmakesuseofPVpanelstopowerthebuilding. Thisprojectisveryefficientandmakesuseofsafematerialsthatarelocallyavailableandeasytotransport.Withthe useofSIPsPanels,constructionisalsomadeeasy.Thebuilding’ssimpledesignandstandardfloorplansensuresits replicability.Thisschemewouldhelpcreateatightknitsocialhousingcommunitywhereresidentscouldlivea comfortable,healthy,andself-sufficientlifestylewithoutanyworryaboutpriceofenergy.

INTRODUCTION

Introduction

Theglobalclimateischangingandwillcontinuetochangeoverthenext severaldecades.Inordertocopewiththesechanges,buildingsmustbe resilientandadaptabletofutureclimaticandweathercondition.

Improvingtheenergyperformanceofbuildingswillgreatlyhelpmitogate climatechangeaslessfossilfuelswillbeburntand,asaresult,therewillbe areductioninCO2emmissions.

UnitedKingdomliesinatemparateregionandisstillmostlyheating dominatedbutduetoclimatechange,thesummersarebecomingwarmer andcombinedwithothermicroclimaticfactorssuchgasurbanheatisland effect,manybuildingsexperienceoverheating.Londonandsomeofits surroudingcountiesseetheworstofthis.Fuelpovertyisalsoabigproblem manyhouseholdsfaceduringwinters.

Thisreportaimstoupgradetheenergyperformanceofanofficebuilding situatedinWycombe,UK.

Thefirstsectionofthisreportwillbrieflyreviewanthropogenicclimate change,thestudyofclimatethroughcomputermodelling,andfuture climatescenariosanditsimplicationsonbuildings.

Next,asiteanalysiswillbeconductedontheofficebuildingfollowedbya thoroughclimateanalysisbasedonthecurrentandfutureRepresentation ConcentrationPathwayscenariosofRCP2.6,RCP4.5,andRCP8.5fprthe yearsfor2050and2080.

TheLETIretrofitmanualwillbeusedasaguidelineforthisproject.The officebuildingwillbemodelledonDesignBuilderandretofitted componentswillbeaddedoneatatimeandthebuilding’sperformancewill beanalysedandassessed.

AnthropogenicClimateChange ComputerModelling

Historically,climatechangehasalwaysoccurredslowlyovermillionsof years.Studiesonclimatechangehaveconsistentlyshownthathuman activityhasbeentheleadingcauseoftherapidincreaseinglobal temperatures.TheTheoryofAnthropogenicClimateChangewasbacked byconcreteprooffrommanyground-basedreportsandsatellite measurementsoflandandocean.Thereisevidencethatmostofthecurrent changestoclimateisduetoburningfossilfuels,whichtendtoemitlarge amountsofgreenhousegasesthattrapshortwaveradiationemittedfrom thesunwithintheEarth’satmosphere.Othercausesincludeuseof aerosols,changesinreflectanceduetolanduseandmeltingicecaps, agriculture,anddeforestation.

Variationsintheclimatesystembecomegreaterduetoglobalwarming. Theyincludeincreasesinthefrequencyandintensityofhotextremes, marineheatwaves,heavyprecipitation,and,insomeregions,agricultural andecologicaldroughts;ariseintheamountofseveretropicalcyclones; andadecreaseinArcticseaice,snowcoverandpermafrost.

ThesixthIPCCassessmentreportstatesthatbuildingsaresolely responsiblefor21%ofglobalgreenhousegasemissionsofwhich57%were indirectlyemittedfromoffsitegenerationofheatandelectricity,24%were directemissions,and18%wereembodiedemissionsfromproductionof cementandsteel.

Generalcirculationmodels(GCMs)arecomputermodelsthatwere developedtounderstandthefutureclimatechangeandnaturalclimate changesthathaveensuedoverthecourseofhistory.

Coupledatmosphere–oceanglobalcirculationmodels(AOGCMs),also knownasanearthsystemmodelsimulatethephysical,chemicaland biologicalprocessesoftheentireglobalclimatesystemincludingthe atmosphereandoceans.Thefactorsthatareaccountedforinclude atmosphericandoceaniccirculationpatterns;effectsofclouds,water vapour,landandseaice,greenhousegases,atmosphericaerosols;impactof volcaniceruptions;andtheuptakeofCO2bytheoceansandbiosphere.

ClimatemodellingcentresworldwidemakeuseofAOGCMstogenerate climatechangeprojectionswhicharesynthesisedandsummarisedbythe IPCC.

Computermodelscalculatethedifferentpropertiesofclimatesuchas atmospherictemperature,pressure,wind,andhumidityonmanydifferent pointsoftheearth’sonathreedimensionalgrid.Thegridsquareswhich wereformerlyaround200kmby200kmarenow25kmby25kmallowing scientiststoobserveindividualweathersystemssuchasstorms.

Scientistsrelyonclimatemodelsastheyaretestedandtheirresults comparedandverifiedwithdatacollectedfromtherealworld.The simulationscreatedbyclimatemodelsarecomparedwithactualclimate datafromtheearth’satmospheretotesttheaccuracyoftheseclimate modelswhicharethenusedtopredictthefutureclimate.Climatemodels arealsotestedthroughsimulationofpastevents.Theseclimatemodelsare basedonphysicsandscientificprinciplessuchastheconservationof energy.Althoughthereisalwaysasmallmarginoferrorthatisexpected whenitcomestopredictingclimate,computersimulationshavebeenused toaccuratelypredictclimateoccurrencessuchastheelniñophenomenon.

Theeffectofglobalwarmingontheearth’sclimatecanbesimulatedand calculatedfordifferentscenariosusingcomputermodelswithgreat accuracy.Thesemodelsareofhighimportanceinthefieldofarchitectureas buildingsmustbedesignedwiththefutureclimateinmindiftheyareto lastforatleast50to100yearswhilebeingclimateresilient,sustainable,and adaptabletoachangingclimate.

WYCOMBE-EXISTINGBUILDING

CLIMATECHANGECAUSEDBYBUILDINGS

Oneofthefundamentalfunctionsofbuildingsistomodifytheexternal climateandprovideacomfortableplaceforhumanstoinhabit.Climatehas animportantroleinthedesignofabuilding.Climateisprojectedtochange duetoanthropogenicactivitiesandinordertodesignbuildingsthatare resilienttoclimatechangeandadaptabletofuturescenarios,itisvitalto understandwhatfutureclimatesmaylooklike.

Thedevelopmentofclimatechangescenariosbeganwithemissions scenarioswhicharebestdescribedasstorylinesforfutureemissionsof greenhousegasesandotheranthropogenicfactorsaffectingtheclimate.

SpecialReportonEmissionScenarios

SpecialReportonEmissionScenarios(SRES)wereusedinearlyIPCC reportstorepresentarangeofconceivablefuturescenariosforglobal greenhousegasemissionlevels.Thesesixscenarioswerecreatedbasedon assumedprojectionsforpopulationgrowth,technologicaladvancement, globalizationandsocietalvalues.

TheA1scenarioassumesafutureofglobalizationandrapideconomicand technologicalgrowthincludingfossilfuelintensive(A1FI),non-fossilfuel intensive(A1T),andbalanced(A1B)versions.TheA2scenarioassumesa dividedworldwithgreateremphasisonnationalidentities.TheB1andB2 scenariosassumeasustainableutopia,B1withaglobal-focusandB2witha moreregional-focus.

Whilesomeofthesescenarioscompriseofgenericnotionsofsustainability andenvironmentalprotection,thescenariosdonotenvisionexplicit attemptstostabilizeCO2concentrationsatanyparticularlevel.Dueto theirsocialcomponent,thesescenariosaredifficulttoaccuratelymodel.

RepresentationConcentrationPathways

TheRepresentationConcentrationPathways(RCPs)replacedSRESinthe FifthAssessmentReportin2013.Thesepathwayscouldpotentiallybe realizedwithmultiplesocioeconomicscenariostakeintoconsideration climatechangemitigationpoliciestolimitemissions.Theywerecreated with'integratedassessmentmodels'whichincludeclimate,economy,land use,demographic,andenergy-usageeffects.Carboncyclemodelswerethen usedtoturntheirgreenhousegasconcentrationsintoanemissions trajectory.

TheRCP2.6scenariorequiresextrememeasurestomitigationof greenhousegasconcentrations.Itpeaksduringthe2040sandgradually declinesby2100.TheRCP4.5andRCP6.0scenariosstabilizeafter2100.

TheRCP4.5andSRESB1scenariosarequitesimilar.RCP6.0issomewhere betweentheSRESB1andA1Bscenarios.TheRCP8.5scenarioistheclosest tocontinuingwithoutmakinganychangesinfossilfuelusageandissimilar toSRESA2by2100.

Inallthepathways,globalpopulationlevelsofforstartstodeclineby2100, withapeakvalueof12billioninRCP8.5.Grossdomesticproduct(GDP) increasesinallcases.TheRCP2.6pathwayhasthehighestGDP,although ithastheleastdependenceonfossilfuelsources.CO2emissionsinall pathwaysotherthantheRCP8.5scenariopeakby2100.

TheSpecialReportonEmissionScenarios(SRES),usedintheUKCP09 projections,didnotincludeanypoliciestolimitclimatechangeandhence

didnotconsiderafuturewithclimatechangemitigation.Theincreasing relevanceofmitigationscenariosledtothedevelopmentofanewsetof scenarios,theRCPs.

RCPseasecollaborationandcommunicationbetweenthescientific communitiesworkingonclimatechange,adaptationandmitigation. UnlikewithSRES,RCPsenablethecostsandbenefitsoflongtermclimate goalstobeevaluated.RCPsarereferredtoas‘pathways’astheyarenot definitiveandunravelviamorethanoneunderlyingsocioeconomic scenario.

ClimateChangeintheUK

Climatechangewillhaveadireeffectontheoperationalenergy consumptionofbuildings.Naturallyventilatedbuildingsmayexperience overheating,consequently,lowenergycoolingsystemsmaynotbeable createacomfortableinternalatmosphere.Mostbuildingsaredesignedto withstandtheclimateformanydecadesandprovideacomfortableindoor climate.Itisimportanttoaddressclimatechangeandtheeffectoffuture climateonpresentbuildingstoextendthelifespanofnewandexisting buildings.

Ithasbeenestimatedthatbuildingsaccountforabout45%ofthetotal energyconsumptionintheUK.Thereissubstantialneedandpotentialto reduceemissions.UKisstillacoolingdominatedcountryandalthough manyregionsexperienceoverheatingduringsummers,it’snotentirely economicallyorenvironmentallyfeasibletoaddmechanicalcoolingto buildings.Thefabricofthebuildingmustbetackledinordertogain controloftheinternalclimateandpreventanyinfiltration.Passive measuressuchasstrategicshadingandoperablewindowscanbeaddedto furtherdecreaseoverheating.TheuseofMechanicalVentilationandHeat Recoveryunitsalongwiththeuseofheatpumpshavebecomeincreasingly commontechnologyinUK,especiallyinenvironmentallyconscious buildings.MVHRsystemsareastapleinanylowenergybuildingasthey increasetheefficiencyofheatingandcoolingsystems.

SiteAnalysis CaseStudies

Thebuildingislocatedinagatedofficepark communityinWycombe,UK.Thebuildingisoriented towardsthewestwhereitrecievessunlight throughouttheyearandwillexperienceatheeffects ofwind.ShadingwillberequiredalongtheSouthand Westtopreventsummeroverheating.Theopenings onthewestwillbeusefulltomaximisenaturalcross ventilationduringwarmermonths.Thebuildingfabric mustbeupgradedtokeepthebuildingwarmduring winter.

SWOTAnalysis

Strengths

•FormFactor–compactbuilding

Opportunities

•Toreduceheatingandcoolingdemandby

tripleglazing

•TointroduceanMVHRsystemtoimproveenergy efficiencywiththeaddedbenefitof

•Toreducedependencyonfossilfuelpowered heatingsystembyintroducingaHeatPump

•Useanon-renewableenergysource,solarpanels, topowerthebuilding

Weaknessess

HarvardHouseZero

ZetlandRoad

Threats

HarvardHouseZeroisaretrofittedpre-1940stimberframedofficebuilding.Theprojectaimedtocreateone oftheworld’smostambitioussustainablebuildings withrigidperformancetargets,suchas100%natural ventilation,100%daylightautonomy,andalmostzero energyrequiredforheatingandcooling.Theresultwill beaprototypeforultra-efficiency,reducingrelianceon energy-intensivetechnologywhilstcreatinga comfortableindoorenvironment.

ApairofVictoriansemi-detachedhousesinZetland Road,Manchester,receivedEnerPHitPlus certificationinNovember2018.Thelowenergy demandforspaceheatingachievedbyhighlevelsof insulationandairtightnessissupplementedwithan 11kWPVinstallation.Incombinationwithenergy efficientappliancesfurtherreducingdemand,the housesgeneratemoreenergythantheyconsume.The focusoftheretrofitwasonminimizingtheu-value whileincreasingsolargainalongwithairtightness.The buildingmakesuseofanMVHRsystemwithanadded woodburningstoveasabackup.

DesignApproach

TheLETIretrofitstandardsuggestsahierarchicalapproachtoreduce operationalenergyofanexistingbuilding:1.Reducethespaceheatingdemand andEnergyUseIntensityasfarasispracticableforthebuilding.2.Remove fossilfuelheatsourcesandreplacewithlowcarbonalternatives.LETIbelieves thatthemainoptionforthisoveratleastthenextdecadewillbeheatpumps. And3.Generaterenewableenergyonsitewhereverfeasible.

Afabricfirstapproachwillbefollowedinthisretrofitproject.Thewalls, floors,andceilingswillbefittedwithefficientmineralwoolinsulation.Any andallgapsandthermalbridgesintheenvelopewillbeinsulatedusingspray foaminsulation.Allwindowswillbefittedwithtriple-glazedelectrochromic windowswhichhelpsmaintaintheindoortemperatureandprevents overheating.TheheatingsystemwillbereplacedwithHeatPumpsandthe HVACsystemwillbeupgradedtoanMVHRsystemwhichwillrecover 70-90%oftheheatfromstaleairleavingthebuilding.AnMVHRsystem wouldalsoprovideacontinuoussupplyofpollution,pollen,anddustfree freshairandwouldalsoridtheinternalspacesofair-bornemicroorganisms. Theexistingthermalmasswillbeusefulinregulatingthemicroclimateofthe building.Duringthesummer,nightpurgingmayhelpcoolthebuildingforthe nextdayandthestairwellwillbeusedtoremoveexcessheatusingstack ventilation.

OPTIONAPPRAISAL

SprayFoam

InsulationMaterial HeatPumps

MineralWool

Advantages DisadvantagesAdvantages

•Expandsquicklyandfills smallcracksandcrevices withease

•Bestforcrawlspaces,knee walls,basementrimjoists

•Actsasanairsealantand preventsinfiltration

•HighR-valueofabout R-2.72percm

•Waterandsagresistant

•Long-lasting

•Expensive

•Propertymustbevacated foratleast12hoursduring installation

•Poorlymixedchemicals canpotentiallyleadto healthrisksandineffective insulation

•Naturallymoistureresistantandretainsits insulatingqualitieseven whenwet.

•Soundinsulating properties

•Burnsataveryhigh temperaturethusactsasa firebarrier

Disadvantages

•Protectivegearmustbe wornwheninstalling.

•Inhalinganyparticlesof mineralwoolcancause lungdisease.

AirSourceHeatPumps

Air-to-waterheatpumpstransferheatfromtheoutsideairinto waterwhichisthenusedtoheatbuildingsthroughradiatorsor underfloorpipes.Theyareextremelyefficientandcost-effective. Theyabsorblow-temperatureheatfromtheambientairdownto atleast-15degreesCelsiusandcanbeupto350%moreefficient thanfossilfuelboilers.Themechanismofanair-to-airheat pumpissimilartothatofanair-to-waterheatpumpandcan helptoheatandcoolaproperty.Thiskindofunittakesinheat fromtheoutsidewhichisthenamplifiedwithacompressor.The airisthenreleasedintothebuildings.

AlthoughbothEPSandXPShavegreatthermalpropertieswhichmakesthemsuitableforinsulatinggroundslabsdirectly,XPShas greatercompressivestrengththanEPSwhichmakesitmoreefficient.XPSalsoperformsbetterinregionswithawetclimateasithas ahighervapourdiffusionresistancevalue.

Disadvantages

andbedrock

GroundSourceHeatPumps

tifreezeliquidburiedundergroundwhichisthencompressed andusedtoheatindoor.Thesystemtransferstheheatabsorbed towaterwhichisdistributedthroughunderfloorheating. WhenlandisavailableGSHPsystemsarelaidinhorizontal trenchesthatareapproximately1-2metresdeep.Verticalboreholesareamoreexpensivealternativewhereholesaredugupto around150m.

Advantages

Advantages Disadvantages

andbedrock

WYCOMBE

CLIMATEANALYSIS

TemperatureRange

Graphshowsthatthisisaheating dominatedclimate.Theaverage highandlowtemperaturesare recordedinthemonthofJulyand January.FewhoursinMay,June, AugustandSeptemberfalls withincomfortzone.Whereas January,February,March, NovemberandDecemberarethe monthswithlowestrecorded temperatures.

RadiationRange

IlluminationRange

Thegraphcomparesthehighesttemperaturerangesof2050 and2080inthreescenarios(2.6,4.5,and8.5)tothecurrent temperaturerange

Incomparisonto2050and2080, theaveragehighesttemperature rangeincurrentscenariosis relativelylow.

2050: Themeanhighest temperaturesarerecordedinthe monthofJuneJulyand August.Thelowesttemperatures arerecordedin2.6scenario.The highesttemperatureisrecordedin 8.5scenario.

2080: 8.5scenariohasthehighest temperaturesofthescenarios.

Highintensityradiationsareresponsibleforrisein temperature.Theradiationofthehourlyaverageis showninthefigureabove.TherangeofDirectNormal RadiationisgreaterthanthatofGlobalHorizontaland TotalSurfaceRadiation.Thegraphdepictsthosehigh radiationsareonlyduringthemonthofMay,June,July andAugust.

Illuminationrangegraph-2022

Thegraphcomparesthelowesttemperaturerangesof2050 and2080inthreescenarios(2.6,4.5,and8.5)tothecurrent temperaturerange

Incomparisonto2022and2050, theaveragelowesttemperature rangein2080isrelativelylow.

2050: Thelowesttemperatureis recordedin4.5scenario.

2080: Thelowesttemperatureis recordedin8.5scenario. Thereisnosignificantdifference betweenlowesttemperaturesin 2050and2080asper2.6and4.5 scenarios.Howeverin8.5 scenario,thereisagradual progression

Thegraphshowstheradiationrangesof2050 and2080inthreescenarios(2.6,4.5,and8.5)tothecurrent

Theaveragehighestradiationrangein2050(2.6)is relativelylowincomparisonto2022and2080.

Thehighestradiationisintheyear2080(4.5)

Thegraphshowsthehighestilluminationrange

Highestilluminationisintheyears2050in2.6 and8.5scenariosandin2080in4.5scenario.

Thegraphshowsthehighestilluminationrange

Lowestilluminationisintheyear2050in2.6and 8.5scenarios

SkyCoverRange

Theaveragehighestandlowestsky coverin2022areinthemonthof OctoberandAugust.Whereas,in 2050and2080itchangeswith3 differentscenarios,i.e.

2050:2.6:Highest-November,

Lowest-August

4.5:Highest-December

Lowest-August

8.5:Highest-January

Lowest-July 2080:2.6:Highest-December

Lowest-August

4.5:Highest-March

Lowest-July

8.5:Highest-November

Lowest–August

Thewindvelocityhasremains consistentovertheyears,with nosignificantchanges.Even thoughthereisaslight increaseintheyear2080inthe south-eastdirection.

WindChart

Thegraphshowsthehighestskyrange

Themeanhighestskycoverwillbein2050 (4.5)and2080(2.6).

PsychometricChartAnalysis

Bycomparingthepsychrometricchartof2022,2050and2080in differentscenarios,itisclearthattherewillbeasignificant increaseincomforthoursasthetemperatureincreasesandmore hoursfallintocomfortzone.Thereisnosignificanteffectforsun shadingofwindowsinthecurrentand2050s.However,shading becomesimportantin2080sespeciallyin8.5-2080scenario.As thetemperatures,risesupinternalheatgainitselfcanbringlotof hoursundercomfort.Itbecomesoneoftheimportantdesign strategy.Highmassbuildingsperformsslightlybetterthanlow massones.Significanceofprotectingfromwindisreducedin futurescenarios.Thereisalargereductioninheatingdemandin futurewhereasthecoolingdemandisincreased.

Current 8.5-2080

TotalEnergy Heating Cooling

Heating

Itisobservedthatin2.6 scenariothetotalenergy demandofthebuildingreduces by2050andthenslightly increasesby2080.Thisis becauseinthisscenarioitis expectedthatquickactionare takenagainstclimatechange andthetemperaturesstarts improving.Inallother scenarios,theenergydemand decreasesoveryears.Therateof decreaseismoreforthe8.5 scenario.

Cooling

Heating

4.5 Heating

Cooling

Cooling

Itcanbeseenthat,by2080,the energyrequiredtoheatthe buildingreducesfrom36972 KWhto29632KWhin4.5 scenarioandfrom36972KWh to24901KWhin8.5scenario. Thetrendisslightlydifferentin 2.6scenario.Thereisno significantdifferencebetween 2050and2080inthisscenario. Because,thisscenarioexpects thatnecessaryactionsaretaken againstglobalwarmingandso therewon’tbesignificantrisein temperature.

Cooling

Itcanbeseenthat,by2080,the energyrequiredtocoolthe buildingincreases.Thebuilding thatrequiredlessthana1000 KWhtocool,requiresmore than3000Kwhin2080asper 4.5scenarioandgreaterthan 7000Kwhasper8.5scenario.A similartrendasbeforeisseenin 2.6scenario.Thoughtheenergy requiredforcoolingincreasesin 2050,itthenstaysalmostthe samein2080.

Overheating

In2006,TheCharteredInstituteofBuilding ServicesEngineers(CIBSE)definedoverheatingas conditionswhenthecomfortableinternal temperaturethresholdof28°Cissurpassedfor morethan1%ofoccupied(working)hoursor where25°Cissurpassedfor5%ofoccupied (working)hours.

Schedule

Month Monday

January 8to18 8to18 8to18 8to18 8to18 8to18

February 8to18 8to18 8to18 8to18 8to18 8to18

March 8to18 8to18 8to18 8to18 8to18 8to18

April 8to18 8to18 8to18 8to18 8to18 8to18

May 8to18 8to18 8to18 8to18 8to18 8to18 Off

June 8to18 8to18 8to18 8to18 8to18 8to18 Off

July 8to18 8to18 8to18 8to18 8to18 8to18 Off

August 8to18 8to18 8to18 8to18 8to18 8to18 Off

September 8to18 8to18 8to18 8to18 8to18 8to18 Off

October 8to18 8to18 8to18 8to18 8to18 8to18 Off

November 8to18 8to18 8to18 8to18 8to18 8to18 Off

December 8to18 8to18 8to18 8to18 8to18 8to18 Off

No.Ofholidays-8days

Groundfloor

Accordingtothisrule,thoughtherearefewhours ineachzonethatgoesabove25degrees,thereare nozoneshasmorethan5%oftheoccupiedhours abovethistemperature.Thegraphaboveshows the%ofhoursthatgoesabove25degrees.Hence groundfloordoesn’thaveoverheatingissuesboth incurrentandanyofthefuturescenariosaswell.

Aspertheschedule,totalnumberofoccupied hoursinayearis3024.Thesimulationsand analysiswererunonlyforthisoccupiedtime period.

Inthecurrentscenario,thereareveryfewhours thatgoesabove25degreesandnohoursgoes above28degrees.Butby2080sasper8.5scenario, fewhoursgoesabove25degrees.Butstillstays lessthan2%.

of hours above 25 deg

Overheated zones

OVERHEATINGANALYSIS

FirstFloor

Asperthethreshold,therearemanyzonesin1st floorthathas morethan5%ofhoursabove25degrees.Butthenumberof hoursabove28degreesstayslessthan1%incurrentandall thefuturescenarios.

NohoursinZone7andZone9goesabove25degrees.Few hoursinZone8and10goesabove25degrees,butthereareno overheatingissuesas%ofhoursstaysbelow5%.Zone 1,2,3,4,5,6,11,12,13and15hasoverheatingissues.Forzone1 and13overheatingissuesoccuronlyin8.5scenariosand mostlyin2080.ButforZone2,3,11,12,13and15,thoughthere arenooverheatingissuesinthecurrentscenario,thereis problemsfrom2050sinallthescenarios.Whereas,Zones 4,5and6areoverheatedrightfromthecurrentscenario.

Thezonesthatfacesoverheatingissuesarehighlightedinred inthebottomrightcorner.Fromthisitcanbeobservedthat thesidethatfacessouth-westdirectionhasthemost overheatedhours,followedbythesouth-eastside.

Thereforestrategieshavetobedevelopedinordertoreduce theoverheatedissues.

Overheated zones

WYCOMBEBUILDING-RETROFITOPTIONS

ROOF

Theeffectofafloorabovewasobservedfromthetemperatureanalysis ofthebuilding.Groundfloordidn’thaveanyoverheatingissues, whereasfirstfloorhadsevereoverheatingissues.So,thefirstretrofit optionconsideredwas,changesinroof.Addingatrussroofontopof theexistingroofwasthefirstoptionconsidered.

Itwasobservedfromthepreviousgraphsthatthezonewith maximumoverheatingproblemisZone6.Henceeffectofeachroof optionswerequantifiedbasedonchangesinZone6.Also,theyear thathasmostnumberofoverheatedhoursis2080in8.5scenario.In additiontothattheoverallenergydemandwasthehighestforthe currentscenario.Hencetheeffectsofallretrofitoptionstothe buildingiscomparedinthese2scenarios.

Thefirstoptionconsideredwasaddingatrussroofontopof theexistingroof.Thesidesoftheaddedspaceconsistsof operablewindows.

Option1 Option3

Inthisoption,insulationlayersareaddedtotheexistingflat rooftoimprovetheUvalue.ThenewUvalueisasperLETI exemplarretrofittarget-0.12W/m2.K.

Thenextoptionhasthesametrussroofonthetopofthe existingroof,butthesidesoftheaddedspaceiskept completelyopen.

Option2 Option4

Inthisoption,isthecombinationofOption1and3.The existingroofisimprovedtoaUvalueof0.12andinadditionto thattrussworkisalsoadded.

Thenewlyaddedspacewasnotaddedinthethermal calculations,becausetheprimaryaimwastoassesstheeffect ofthisnewlyaddedspaceinthefirstfloor.Theenergy consumptionofthebuildingswerecomparedwithexisting energyconsumptionandtheoverheatedhourswerecompared withthe8.52080scenario.Thefirst2optionshadsimilar performancebothinenergyconsumptionandoverheated hours.Theyhelpinimprovingenergyconsumptionand overheatedhours.Butthebestperformanceintermsofenergy andoverheatedhoursisgivenbyOption3.Inoption3the energycomesdownto128.64Kwh/m2/yearfrom168.73Kwh/ m2/year.Withthisimprovement,thereisnooverheatedhours in2080scenario.Hence,theaimofoption4wastoaddtruss rooftoOption3,tocombineadvantagesofboth.Butno significantreductioninenergyandoverheatedhourswastobe foundevenafteraddingtruss.SoOption3seemstobethebest.

WYCOMBEBUILDING-RETROFITOPTIONS

Energy Comparison

Ofalltheoptions consideredforroof, Option3performs better.Option4of addingtrussroofon topofretrofitted roofhelpsin reducingenergy, butveryless(2 KWh/m2/year).

Thisisnotasignificantreductionandsoaddingtruss roofdoesnotmakeaconsiderableimpact.Hence Option3waschosenforthefurtherstudy.Thelayers ofretrofittedroofisasshownabove.

Roof Walls

Thenextoption consideredwas improvingthewall insulationinthe interiorlayers.LETI exemplarretrofit targetforwallsis 0.15W/m2.K.Hence wallswere improvedtoachieve thisUvalue.

Insulatingthewallsandmakingthestructureairtight hasbeenfoundtolowerenergydemand.However, differentfromotheroptions,theenergydemandin 8.5-2080scenarioishigherthancurrentdemand whenbuildingismadeairtight.Furtherstudieswere donetoidentifythereasonforthisshiftinpattern.

Abovegraphquantifiestheeffectofboththeoptionsonthepercentageofoverheated hours.WhentheUvaluesofthewallsareimproved,ithelpsinfurtherreducingthe numberofoverheatedhours.Butwhenthebuildingismadeairtightthenumberofhours above25degreesincreases.Thisisbecause,theimprovedair-tightnessmakesthe buildingwarm.Thiswillleadtotheincreaseincoolingloads.Figuresalsopointsoutto theimportanceimplyingproperventilationstrategiesforsuchairtightbuildings.

Uvalue-0.15W/m2.K

PURpolyurethaneboardsareusedforthesimulations, howeverotherinsulationoptionsarealsodiscussedin thisstudy.Referpage5. Afterimprovingwallinsulationandanalyzing changes,theairtightnessofthebuildingwas improvedtomeetLETIexemplarretrofittarget-0.1 ach@50Pa.Theeffectofimprovingairtightnesswas analyzedseparately.

AirTightness

2optionswerestudiedtoquantifytheeffectof improvingUvaluesofthewallsandimprovingair tightnessofbuildings.Inoption1,onlytheUvaluesof thewallswereimproved.WhereasinOption2,both Uvaluesofthewallsandair-tightnessofthebuilding wereimproved.

Acomparisonofimprovedwallandimprovedwall&air-tightness optionsweredoneinbothcurrentand8.5-2080scenariostoidentify thereasonfortheincreaseinoverallenergyin8.5-2080scenariowhen thebuildingwasmadeairtight.Itcanbeclearlyobservedfromthese graphsthattheoverallheatingdemanddrasticallyreducesandthe coolingloadisincreasedwhentheair-tightnessofthebuildingis improved.Inadditiontothatcoolingloadsincreasein2080s.Different fromotheroptions,thisleadstoslightlyincreasethetemperaturein8.52080thancurrentscenario.

Boththe‘improvedwall’and‘improvedwall&air-tightness’options werecomparedseparately.Forbothcurrentand2080scenarios, improvingtheair-tightnessofthebuildinghassignificanteffectin reducingheatingdemands.Thereisnegligibleeffectoncoolingloads andnoeffectonotheraspects.Thisshowsthatifthebuildingsaremade airtight,properventilationstrategiesmustbeemployed.Elsethatwill leadtooverheatingandincreaseinenergyconsumption.

WYCOMBEBUILDING-RETROFITOPTIONS

FLOORS-GROUNDFLOOR

Groundfloor

Energy comparison

Energy comparison

Thenext interventionwas madetoground floor.Generally uninsulated groundfloorsare responsiblefor largenumberof coldhoursinthe building.So improvingground floorcanhave significanteffect onthebuilding. So,insulationwasaddedtothegapsbelowthe existinggroundfloorslabtoachieveLETIexemplar retrofittargetforfloors-0.15W/m2.K.Theeffectof thisimprovementinenergyperformanceandover heatedhourswerequantified.Theresultsare comparedwiththeresultsofthepreviousintervention toseewhatdifferencethisbringstothebuilding.

Uvalue-0.150W/m2.K

Improvingthegroundfloorhasconsiderableeffectsonheatingand coolingloads.Itdrasticallyreducestheheatingdemandbothincurrent and8.5-2080scenario.However,thecoolingloadisslightlyincreased incurrentscenarioanddrasticallyincreasedin2080scenario.

First floor %

Improvingthegroundfloorinsulationreducestheenergydemandin thecurrentscenarioto101.43Kwh/m2.However,theenergy demandinthe8.5-2080scenarioincreases.Theincreaseisevenmore thanthepreviouscondition. Improvingthegroundfloorinsulationhadasignificanteffectontheoverheatedhoursin eachfloors.Plottingtheoverheatedhoursshowsthat%ofhoursabove25degrees drasticallyincreased.Theincreaseisevenmorethantheperformanceofexistingbuildingin 8.5-2080scenario.Thisresultspointsouttotheneedofobservingtheeffectofthis interventioningroundfloortemperaturesaswell.

Whentheoverheatedhoursingroundfloorwasplottedagainsttheperformanceofexistingbuilding,itis observedthatthebuildingfacesseriousoverheatingproblems.Therewasnooverheatinginthebuilding previously.Thisshowsthattheuninsulatedgroundfloorwasresponsibleforcoolertemperaturesinsidethe building.Whenitisproperlyinsulated,ithelpsinreducingtheheatingdemand.However,itleadsto overheatedhoursinsummersandfuturescenarios.Thisissueneedstobeaddressedinfurtherinterventions.

WYCOMBEBUILDING-RETROFITOPTIONS

INTERNALPARTITIONS

Internalpartitions

Uvalue-0.858W/m2.K

Theeffectof improving internal partitionswere analyzed.10mm insulationboards wereaddedon eithersideof existing partitionsto improvetheU valuefrom 1.639 W/m2.Kto0.858W/ m2.K.

Theeffectofthisinterventionisquantifiedand comparedwiththepreviousintervention.

Energy comparison

Annualenergygraphshowsthattheoverallenergyslightlyincreases bothincurrentand8.5-2080scenarios.Inthecurrentscenarioit increasesfrom101.43KWh/m2to101.69KWh/m2.In8.5-2080 scenario,itincreasesfrom111.65KWh/m2to111.74Kwh/m2.

Energybreakdownshowsthat,thisinterventionslightlyincreasesthe heatingdemandincurrentand8.5-2080scenarios.Coolingdemandis slightlyseentoreduceinbothcurrentandfuturescenarios.Onlya negligibleeffectisseenwiththisimprovementininternalpartitions.

Overallitcanbeobservedthat,improvingtheinternalpartitions,slightlyincreasesthenumberofover heatedhoursinsomezone.Anegligibledecreaseisalsofoundinsomezones.Howevermostofthehours liesjustabove25degreesandthenumberofhoursabove26degreesandtemperatureabovethatisslightly reduced.

Firstflooralsoshowsthesametrendbyimprovingtheinternalpartitions.Overallheated hoursincreases,butmostofthehoursliesin25degreesband.Thisisthereasonforhaving increasednumberofoverheatedhours,butslightreductioninthecoolingdemandsin currentandfuturescenarios.

WYCOMBEBUILDING-RETROFITOPTIONS

OPENINGS

Windows

Uvalue-0.780W/m2.K

LETIexemplarretrofittargetforwindowsis0.8W/ m2.K.Hencetheexistingdoubleglazedwindowsthat hadaUvalue-2.761wasreplacedwithtrippleglazed unitswithUvalue-0.780W/m2.K.Theeffectof trippleglazedwindowsineachzoneswereanalyzed andcompared.

Makingthewindowstrippleglazedbringsdownthecurrentenergy demandfrom101.69KWh/m2to87.78KWh/m2.However,thereis verylessenergyreductionin8.5-2080scenario.Differencebetween theenergiesincurrentand8.5-2080scenarioalsoincreases.

Trippleglazedwindowshelpsinreducinglightingenergydemand bothincurrentandfuturescenarios.Thereisdrasticreductionin heatingdemandwhereasthecoolingloadalsoincreasesaccordingly. Thisbecomesthereasonforincreasedenergydemandin8.5-2080.

Makingthewindowstrippleglazedhastremendouseffectonthenumberofoverheatedhoursinthe building.Thefiguresarealmostdoubledthanthepreviousoptionsandthisleadstotheincreasedcooling demand.Thereinincreaseinthe%ofhoursthatgoesabove28degreesaswell.

Firstfloortemperaturesalsoshowasimilarincrease.Thesefiguresalsopointsouttothe necessityofimplementingproperventilationstrategiesandshadingstrategiesinsummerto avoidoverheating.

WYCOMBEBUILDING-RETROFITOPTIONS LIGHTING

Lighting

Energy comparison

Energy comparison

TheexistingbuildingconsistsofmostlyT12 Fluorescent,halophosphate,lowfrequencycontrol lights.Thelightswerereplacedwithhighefficiency LEDlightswithlinearcontroltosaveenergy.Lighting hadconsiderablecontributiontotheinternalheatgain inthebuilding.Henceitsimpactwasquantifiedinall theaspects.

Thereisconsiderablereductionintheenergydemandbothin currentand8.5-2080scenarios.Thisshowsthatlightingstrategies haveastrongimpactintheenergyconsumptioninthebuildingsand thisimprovementcanbringahugedifference.

Lightingdemandconsiderablyreducesbothincurrentandfuture scenarios.Improvingthelightingslightlyincreasestheheatingdemand lowersthecoolingdemand.Reductioninthelightingenergy contributestotheoverallenergyreduction.

Improvingthelightingstrategiesconsiderablybringsdownthenumberofoverheatedhoursin groundfloor.However,itisstillhigherthantheexistingbuildingconditionsandhencefurther strategiesmustbeexploredtotacklethisissue.Alargedifferenceisseeninthezoneswith southwestexposure.

Numberofoverheatedhourshaveconsiderablereductioninthefirstflooraswell.Thispointsoutto thefactthattherewaslotofheatgainfromthelightingsystemsandimprovingthemhavea considerableeffectinreducingenergyconsumption.Improvinglightingstrategieshaveaconsiderable effectinenergyconsumptionandhenceitisanimportantstepwhenretrofittingbuildings.

WYCOMBEBUILDING-RETROFITOPTIONS

Option3performsbestofall

inreducingthenumberof overheatedhours. Percentageofoverheated hoursisreducedlessthan 5%inmostofthezones exceptZone11,whichhas southeastexposurealso.But stillthehoursaremorethan theoverheatedhoursinthe existingbuilding.The shadingiseffectivefor buildingonlyinthefuture scenarios.Theydon’tshow significantimpactinthe currentscenario.

InOption3,operablelouvershavebeenaddedtosouthwestside,thatcanbe deployedinthesummerperiodandsoutheastsideremainssameasoption2.

Option3performsbest ofall.Totalenergy almostremainssame forboththeconditions. Thereisslightincrease inlightingandheating energyinboth scenarios.Thereisa slightreductionfor coolingdemandin currentscenario, whereasthecooling demandisdrastically reducedinthe8.5-2080 scenario.

Asingroundfloor,Option3 performsbestinreducing numberofoverheatedhours. Overheatingisnot completelysolvedinanyof thezone,howeverthehours arecloserto5%exceptin zone11and15thathasgot south-eastandnorthwest exposuresrespectively.But differentfromgroundfloor, thenumberofoverheated hourshavecomedown drasticallythaninthe existingbuilding.

Groundfloor

ExceptinZone11, percentageofoverheated hourscomesbeloworcloser to5%.Zone11alsohave significantreductionin overheatedhoursfromthe previoussimulation.Further stepsneedtobetakento reducethenumberof overheatedhoursinZone11. Thoughshadingdoesn’t haveasignificantrolein currentscenario,theyare veryimportantinfuture scenarios.

EastOption3(E3)

NorthOption1(N1)

Inthisoption,anadditionalfinhasalsobeen addedtoshadefromsouthsun.

ThoughOption3performs best,thereisnosignificant differencefromOption2. Whentheenergyreducesfor the8.5-2080scenario,the energyincreasesforcurrent scenario.Abalancebetween boththeseisexpectedand henceOption2ischosenas thefinaldesign.Thereis slightincreaseinheatingand lightingdemandsinboththe scenariosandcoolingdemand reducesin8.5-2080.

Firstfloor

Asingroundfloor,shading helpsinbringingdown overheatedhoursinfirst floor.However,stillhours aregreaterthan5%.When comparedwithexisting building,performanceis improved.Itcanbeseenthat allthezoneshavesignificant reductioninthenumberof overheatedhoursthanthe previoussimulations.This showstheimportanceof shaddinginbringingdown overheatedhoursinwell insulatedbuildings.

Innorthsideonlyoverhangshavebeengivenas additionalfinsimpactlightingenergy.

WYCOMBEBUILDING-RETROFITOPTIONS

NorthSide

Lookingatallthegraphsit canbeobservedthatthereis nosignificantincreaseor decreaseintheenergy demandswhenshadingis introducedinthenorthside. Thereisnegligibledecrease andincreaseofenergy demandin8.52080and currentscenarios respectively.Lighting,heating andcoolingdemandsalso haveslightvariations.

Groundfloor Firstfloor

The%ofoverheatedhours arereducedinZone1, Howeverthepercentageof overheatedhoursarevery highbecausecoolingwas turnedoffduring simulationsasitisa bathroomspace.Thehours comesdownbelow5%in zone15andZone6alsohave animprovedperformance afteraddingshading.

Summary

Theeffectofallshadingstrategiesongroundflooraresummarizedinthisgraph.Zones1,2,11,12 and18stillhaveoverheatedhoursmorethan5%inthisworstcasescenarioof8.52080.Thehours aremorethanthehoursinexistingbuilding.

Sameasingroundfloor Zone1isToiletspaceand hencecoolingwasturned offduringsimulations.Both thezoneshavereductionin overheatedhours,however, thepercentageof overheatedhoursarestill higherthan5%.Further increasingtheshadingwill leadtoincreaseinlighting energy.

floor

Theeffectofallshadingstrategiesinfirstflooraresummarizedinthisgraph.Exceptzones7,8,9,10and 13allotherzonesstillhaveoverheatedhoursmorethan5%inthisworstcasescenarioof8.52080. Howeverthereissignificantimprovementinthanoverheatedhoursintheexistingbuilding.

WYCOMBEBUILDING-RETROFITOPTIONS

ElectrochromicWindows

Itisanelectronicallytintableglass,thatcan dynamicallycontrolglarefromdirectsunor brightskywhilemaintainingoccupantcomfort, maximizingaccesstodaylightandoutdoorviews andreducingenergycosts.Withasufficiently largerangebetweenclearandfullytinted,EC glazinghasthepotentialtocontrolglarefrom directsunorbrightpatchesofskythereby greatlyreducingorperhapseveneliminatingthe needforadditionalinternalorexternalshading.

Theenergysavingpotentialofthesewindowswere testedinthisproject.Twooptionsweretriedout. Option1consideredusingdoubleglazed electrochromicwindowsandoption2,considered trippleglazedelectrochromicwindows.Triiple glazedwindows performedbetter.Itwasseenthat thesewindowshelpedinreducingenergydemand by5.34Kwh/m2/yearincurrentscenarioandby 3.62Kwh/m2/yearin8.52080scenariowithlarge savingsinlightingenergydemand.

ShadedOption Option1,2

Energy comparison

Observations&Limitations

TheprojectfollowedtheguidelinesofLETIexemplar retrofittarget.ThetargetenergyasperLETIbestpractice retrofitis50Kwh/m2/yearandasperLETIexemplar retrofitis40Kwh/m2/year.Fabricandothercomponents ofthebuildingwereimprovedtomeettheseenergy targets.However,itisseenthatevenafterfollowingall theguidelines,theenergyofthisbuildinghasonlycome downto64Kwh/m2/yearincurrentscenarioand72 Kwh/m2/yearinextremeworsescenior(8.5-2080).Some ofthefollowingaspectshavenotbeenquantifiedin designbuilder.

Systemsandappliances :Analysisshowsthatthereis significantheatgainfromappliancesandcomputers.So thehighlyefficientsystemsandappliancesmustbeused. Therelimitationstoquantifytheeffectsofthesechanges indesignbuilder.

HVACsystems :Thesimulationsindesignbuilder showsmostenergysavingswhenusinggasboilerswhich weknowisnottrue.Maybeitisbecauseofthesystem design.ThoughdesigningHVACsystemstemplatesdoes notcomeunderthescopeofthisproject,theeffectof otherHVACsystemshavenotbeenquantified.

Hotwater :Aspectsmentionedaboveneedtobetaken careofduringretrofit.

Electro-chromicwindowsslightly helpsinreducingtheoverallenergy demand.Comparedtotheshaded windowoption,savingsinlighting energyishigher.Thereisnosavingsin heatingandcoolingenergy.Though totalenergysavingsbyECwindowsare notsignificant,thereisasignificant reductionintheoverheatedhours. Overheatinginallthezonesare elliminatedevenin8.52080scenario, exceptin2zonesthatarenotair conditioned.

WYCOMBEBUILDING-RETROFITOPTIONS

SENSITIVITYANALYSIS

Intheinterventionssofar,theUvaluesandother specificationsasperLETIexemplarretrofitstandard wasfollowed.However,theenergytargethasnotyet beenachieved.Thisdemandsforimprovingthe specificationsmuchmorethanthedemandsofthe standard.ImprovingtheUvaluesorother specificationsofalltheaspectscanleadtolarge increaseinthecost.Itisimportanttoknowwhichof theparametersarethemostinfluentialinreducingthe energydemand.Henceasensitivityanalysiswas performedtoidentifythemostinfluentialparameter.

SensitivityAnalysis

Inthisstudy,theprimaryaimistodosensitivity analysistofindeachdesignparameter'shierarchyof influenceratherthanuncertainty.Hence,eachdesign variablewasconsideredequalprobability,soall variableshaveuniformdistributioncurves.

Lhssamplingmethodisusedforsettinguptheanalysis. Latinhypercubesamplingisahighlyefficientsampling method.Asaruleofthumb,asamplesizeof10times thenumberofdesignvariableswillbesufficientforthe populationmeantobeaccuratelymodelled.So,almost 200simulationswillbeenoughtogetreliableresults. However,toincreaseconfidenceandreliability,a samplesizeof250wasrequestedineachanalysis.

Theregressionsensitivitymethodisusedforthis analysis.Regressionanalysis(multiplelinear regression)isastatisticalmethodthatestimatesthe relationshipsamonginputvariables.Regression analysishelpstounderstandhowtheoutput'stypical valuechangeswheninputvariablesarevaried (assumingthattheinputvariablesareindependentof eachother).

Results

Recently,sensitivityanalysistechniqueshavegaineda lotofattentionasamethodofidentifyingthemost influentialvariablesinbuildingdesign.Sensitivity Analysiscanquantifytheeffectofeachbuilding envelopeparameteranddiscovercriticaldesignchoices toimprovethethermalenvironmentandminimize energyconsumption. ResultsshowsthatusageofECwindows,and improvingtheUvaluesofexternalwallsandroofscan helpinreducingenergysignificantly.Followingsection explainstheresultsindetail.

Netsiteenergyconsumption ismoststrongly influencedbyGlazingtemplate,howeverthere isaninverserelationship.Whichmeans, trippleglazedECwindowshelpsreduce energy.Netsiteenergyconsumptionisalso stronglyinfluencedbyExternalwall construction.Totalenergyisalsomoderately influencedbyflatroofconstruction.Ground floorconstruction,Partitionconstruction, InternalfloorconstructionandAirtightnessdo nothaveanotableinfluenceonNetsiteenergy consumption,therefore,theseinputscanbe

ignoredinfurtheranalysisofNetsiteenergy consumptionforthismodel. AdjustedR-squaredvalue: Itrepresents goodnessoffitofthecompletemodel.It indicateshowmuchvariationoftheoutputis explainedbytheinputvariables.Forthe output:'Netsiteenergy(Netsiteenergy consumption)',the'adjustedR-squared'value of'0.9995'ishigh,suggestingthatmostofthe keysensitiveinputvariableshavebeen identified.Onlyafewinputvariablesmightbe

Outputparameters Inputparameters

leftthatcanimprovetheresults.Thecurrent resultscanbeusefullyconsideredtoidentify mostandleastsensitiveinputvariables.

p-value: Thisvaluetellsiftheinputvariable hasastatisticallysignificanteffectonthe output.Someinputvariableshaveap-value morethan0.05,suggestingthatthereislow levelofconfidenceintheirrespective regressionresultvalues.Theyarethe following:

1.Airtightness(0.1478)

Externalwallconstruction U-0.13 U-0.15 U-0.17

Flatroofconstruction U-0.10 U-0.12 U-0.14

Groundfloorconstruction U-0.13 U-0.15 U-0.17

Partitionconstruction U-0.78 U-0.80 U-0.82

Totalenergy

Glazingtemplate

Trippleglazedclear LoEArgonfilled Sageglasstripple glazedElectrochromic

Internalfloorconstruction U-0.18 U-0.20 U-0.22

Airtightness 0.80 1 1.2

Currentscenario

Existingbuilding

Retrofitbuilding

Currentscenarioand extremeworse condition(8.52080) hasbeenchosenfor comparisonbetween existingandretrofit buildings.Theretrofit buildingshows considerablereduction inallthefuelsenergies. Temperaturegraphs revealthatthebuilding hasbecomemuchmore warmerand comfortable. Infiltrationhasbeen reduced,andlightingis alsoimproved.Heating demandisalsoreduced. Howeverthereis increaseincooling demand.Computer equipments contributestolotheat gainandhenceefficient systemsmustbeused.

8.5-2080scenario

Existingbuilding

Retrofitbuilding

In8.52080,thereis significantreductionin lightingandheating demand.However thereisincreasein coolingdemand.The reductioninheating energyandincreasein coolingenergyisfar higherthaninthe currentscenario.Total freshairtothebuilding isalsoimproved.