PRIORY GREEN ESTATE Term 1 Refurbishing the City Architectural Association_SED
Anusha Nanavati, Thajnu Rashid, Shruti Shiva, Trishta B Vardhan Architectural Association SED 2015-16
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Msc + MArch Sustainable Environmental Design 2015-2016_ Architectural Association School of Architecture AUTORSHIP DECLARATION FORM Term 1 Project : Refurbishing the city: London Case Studies TITLE : PRIORY GREEN ESTATE NUMBER OF WORDS : STUDENT NAMES : ANUSHA NANAVATI THAJNU RASHID SHRUTI SHIVA TRISHTA B VARDHAN DECLARATION “We certify that the content of this document are entirely our own work and that any quotation or paraphrase from the published or unpublished work of is duly acknowledged.” SIGNATURES:
DATE : 18/12/2015
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Architectural Association SED 2015-16
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SUMMARY This report on Priory Green Estate represents the final outcome of the Term 1 of the Sustainable Environmental Design Graduate Master at the Architectural Association School of Architecture. The aim of this research is to understand the design principles of a building, its relation with the climate and the urban microclimate, towards a process of field work, measurements analytical work and parametric simulation. Priory Green is a modernist urban development from the 50s, which was a landmark social housing during its time. But it fell through a severe patch of deterioration before only recently gaining its heritage status. It was thereafter adopted by the Peabody Estate and went through some basic refurbishments. Our strategy to approach this project was identification of possible areas of interest or concern, through site visits and field work. Through this we looked at the large courtyard and its thermal comfort and its relationship to activity pattern. Further we studied one apartment as a base case and modified with different parameters such as insulation, night shutter, natural ventilation and glazing percentage to explore the potential of making the estate free running
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ACKNOWLEDGMENTS We would like to express our sincere gratitude to our esteem project tutor Mr. Jorge Rodriguez, for his guidance and encourging us to strive even better.The faculty of Architectural Association School of Architecture, Sustainable Environmental Design programme tutors; Mr Simos Yanna (programme director), Ms. Paula Cadima and Ms. Mariam Kapsali for their valuble feedback throughout the course of our project. We would also sincerly appreciate Mr Nick Baker, Mr. Gustavo Brunelli, Mr Byron Mardas and Mr Herman Calleja for their critical and valuble advices which led to the developement of the project in a great way. In addition we would like to thank Mr Micheal Muiruri, Neighbourhood Manager at Peabody Trust, for his support and the assistance in providing us with critical information regarding our case study. An honourable mention goes to the residents of Priory Green Estate and, in particular Mr. Norman Type, who has tolerated our frequent visits, given us useful information and co-operated with us in order to try to make this project as accurate and useful as possible. We would also like to thank our classmates for their constant support, presence and encouragment throughout the project. Lastly, we would like to thank our families for giving us the chance to study at the Architectural Association. Without their support this would have been a dream.
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TABLE OF CONTENTS INTRODUCTION 1.
OVERVIEW 1.1 1.2 1.3 1.4 1.5 1.6
2.
Introduction to Site History Site Analysis Climate Study Building Fact File Typology
OUTDOOR STUDIES 2.1 2.2 2.3 2.4 2.5
3.
Solar Access Analysis Illuminance Study Wind Study Field work measurements Comfort Analysis - PET Calculations
BUILDING ENVELOPE 3.1 Sectional Analysis 3.2 Heat Loss Analysis 3.3 Thermal Camera Studies
4.
INDOOR STUDIES 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5.0 5.1
6. 6
Case Study Description Building Typology and Occupant Study Spot Measurements Data Logger Analysis Illuminance Analysis Sun Path Studies Window to Floor ratio Analysis DayLight Autonomy Studies Interior Illuminance Analysis Base Case Thermal Stimulations Balcony Studies
CONCLUSIONS
INTRODUCTION The aim of the project, “Refurbishing the city� is to use the built space of london as our open air laboratory to measure the performance of the buildings, their environmental features and their interaction with the surrounding microclimate. This, together, with the contribution of weekly lectures, workshops and tutorials, and a consistent published literature, lead us to a deeper understanding of the design choices and their effect on the performance of the buildings as well as the possibility to identify possible refurbishment strategies and new design inspirations. The group chose Priory Green estate over 8-10 proposed case studies, because it was a post world war social housing structure. We wanted to study the materials and construction techniques of that time and how it performs about 50 years post occupancy. In addition, we wanted to explore the extent to which refurbishment strategies can be employed to make a free-running structure. We started our reseach work simultaneously with investigation in available literature and field work, which included several visits to the site, taking spot measurements of air temperature,humidity, lux and surface temperature, as well as conducting surveys with the residents and the neighbourhood manager. In the following sections, analysis using softwares like OpenStudio, EnergyPlus , Ladybug, RaymamPro, Diva, FlowDesign, Grasshopper, optivent and soft computations have been compiled to give us critical data needed to sustainabily refurbish the estate. Architectural Association SED 2015-16
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1.1 Introduction to Site “I love that it is so central and I can transport to anywhere conveniently”
CLIENT
- Borough of Finsbury
ARCHITECTS - Lubetkin and Tecton (Pre war design) Lubetkin, Bailey and Skinner (completion) STRUCTURAL ENGINEER - Ove Arup Priory Green Estate is located within the borough of Islington, in North London. Latitude 510 31’ 59.04” N
Longitude 00 06’ 56.17” W.
Priory Green Estate is an exemplar post war social housing
“The public space is a valuable aspect of the neighbourhood”
situated just north of King’s Cross. It stands as a testiment to early modernist housing. And due to its unique status as a heritage building, it finds itself asserting it’s relevance even today.
Fig.1.1.1 Location of the site
Fig.1.1.2 Bird’s eye view of the site
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1.2 History
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“Tecton project for working class flats (1935) were identified as the prototype for improved public housing.” (Malcolm 1981) Fig.1.2.3 street layout layout showing showing extent of pre-war Fig.Busaco Busaco street site (Allan 1992)
Fig.1.2.1 Poor housing conditions of of workFig. Poor housing conditions working class (www.urban75.net) ing class (www.urban75.net)
extent of pre-war site (Allan 1992)
Two main social evils in this period was poor housing and widespread ill-health.
The original scheme - Two eight-storey blocks were aligned north-south with a large green recreational space in between.
The housing problem - Majority of workers were not able to afford a living space that would provide a minimum quality of life and amenities.
The plans of each pair of flats were reversed providing entrances through half landings of staircases. Thus east facing flats were positioned half a floor higher than west facing flats.
Fig.1.2.2 ‘The houses that are needed’ the daily worker newspaper article (Malcolm 1981)
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Tightly packed slums of Busaco street were replaced by the new apartments and greenery.
Fig.1.2.4 Presentation plan of Estate (Malcolm 1981)
Construction Phase 1 The post - war design Site substantially enlarged to 8.75 acres, by bomb damage and budget reduced due to lack of government funds.
Fig.1.2.5 Aerial view completed main scheme (Allan Fig.1.2.5 Aerialview view of of mainmain scheme (Allan 1992) 1992) Fig. Aerial ofcompleted completed scheme
Fig.1.2.7 Aerial view of Present condition of site and surroundings (Source-Google Earth)
Two eight storey blocks with 269 flats (mainly 4-room flats)
1998 - Peabody was appointed by Finsbury council (now defunct) to regenerate Priory Green
Other facilities included community centre, well appointed laundry and public house.
The communal areas and facilities were upgraded with new landscaping, kids play area, improved lighting, new refuse store and some improvements to the interiors along with repair of the central heating system.
The large apartment blocks along with the adjacent terraces were visible from Euston Road.
JMCT Architects designed Hugh Cubitt House, the new community centre managed by Peabody to provide services to the residents. 2011 - Solar photovoltaic (PV) panels were installed at Priory Green by Breyer Group. These power communal electricity systems such as the lifts, communal lighting and the communal TV aerial for the building.
Fig.1.2.6 View of principal block
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
1.3 Site Analysis The Priory is one of the tallest built form in this area. And it is bound mainly by residential buildings along with a school and community centre on east side.
Fig.1.3.1 Figure ground of the site and nearby buildings
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The site is well connected in terms of public transport and road network with Angel and King’s cross underground stations in close proximity.
Fig.1.3.2 Major road network around the site
The site houses green spaces within the estate and is flanked by an outdoor garden on the south side.
Fig.1.3.3 Green spaces within and at close proximity to the site
1.4 Climate Study The weather Station - Angel/ Farringdon Located at 1.1 mile from Priory Green Several references has also been made using Mateonorm to assist in the daylight studies.
Fig.1.4.1 London sky condition frequency % (Source - Satel-light)
Fig.1.4.3 A satellite image showing the location of the weather station with reference to the Priory Green Estate site (Source - www.wunderground.com)
Fig.1.4.2 Graph showing global and diffuse radiation (Source - Mateonorm) Fig.1.4.4 Graph showing the mean monthly temperatures of London (Source - www.wunderground.com)
Fig.1.4.2 Graph showing global and diffuse radiation of London (Source - Mateonorm)
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
1.5 Building Fact File NO OF UNITS
- 192
NO OF STOREYS
-8
UNIT FLOOR AREA
- 78 sqm
COMMON SPACE AREA
- 1,384 sqm
AREA OF EACH BLOCK
- 10,080 sqm
In considering the overall layout of the site, Tecton was determined to develop a housing scheme which had significant entrances and recreational spaces.
Fig.1.5.1 View of Hugh Cubitt Centre
Fig.1.5.1 Hugh Cubitt Centre
Fig.1.5.2 The play area in Courtyard
Two blocks are symmetrically arranged on opposite sides of a spacious garden, creating a proportion and scale intended to reflect the quality of a London square, with trees, hard surfaces and seats as part of landscaping.
Entry Fig.1.5.4 View of Priory Green Estate
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Fig.1.5.3 Seating space
1.6 Typology
Fig.1.5.6 Isometric view of block A
Alternate placing of each apartment unit on successive floors, generates a three-dimensional stagger pattern which contrasts with the adjoining block’s gallery facade.
Fig.1.5.5 Typical plan of a block
The tripartite division of eight storey blocks mitigates the long horizontal effect of the cantilever corridors creating a large scale pattern. The arrangement of rooms and service ducts are symmetrical about the structural column.
Fig.1.5.8 Isometric projection showing the construction of the block (Source - Malcolm 1981)
The four way cast iron grid defines the checker squares and acts as a storm water drainage pipe.
Fig1.5.7 Isometric view of block B
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“ Myself not so much. There is nothing much in it . Its only a space in between: I do sit in the park across the road.” - On being asked whether they used the courtyard - Priory Green Resident
“ Families do bring young children in the evening, but thats about it.”
- On being asked whether they used the courtyard - Priory Green Resident
OUTDOOR STUDIES Architectural Association SED 2015-16
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
2.1 Solar Access Analysis
We started with the outdoor analysis to understand the relationship between the built form and the open spaces. The first stimulation run by the team has been the sun patch, calculated for 21st June (Summer Solstice), 21st March(Equinox) and the 21st December (Winter Solstice).
21st June Summer Solstice
21st March_Equinox
22nd December Winter Solstice
The sun path diagram (fig: 2.1.1),when read in tandem with the built form analysis reveals the following aspects: -Facades receiving most solar radiation during the summer are the ones facing the East and South, owing to which the East and West sides have a responsive sectional detail, which will be discussed in detail in the later sections of the book.
Fig. 2.1.1.1 Summer Equinox Overshadow (Morning)
Fig. 2.1.1.2 Summer Solstice Overshadow (Morning)
Fig. 2.1.1.3 Winter Solstice Overshadow (Morning)
Fig. 2.1.1.4 Summer Equinox Overshadow (Afternoon)
Fig. 2.1.1.5 Summer Solstice Overshadow (Afternoon)
Fig. 2.1.1.6 Winter Solstice Overshadow (Afternoon)
Fig. 2.1.1.7 Summer Equinox Overshadow (Evening)
Fig. 2.1.1.8 Summer Solstice Overshadow (Evening)
Fig. 2.1.1.9 Winter Solstice Overshadow (Evening)
-Most facades are in shade during the winters, barring a short duration in the afternoon, with the maximum being received by the South-facing facades. However, as the south facade consists of deadwalls and stairwells, none of the circulation or apartment spaces benefit from this.
Fig. 2.1.1 illustrates the overshadowing of the built form on the courtyard. Source: RHINO + Ladybug
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21st June_Summer Solstice
22nd December_Winter Solstice
“I like sitting on the bench on the other side of the road.� -Priory Green Resident
Fig. 2.2.1.1 Summer Solstice Illuminace levels (Morning)
Fig. 2.2.1.2 Winter Solstice Illuminace levels (Morning)
2.2 Illuminance Study
We began studying the various parameters that affect thermal comfort in the courtyard to understand its relationship with activity patterns. Fig. 2.2.1.3 Summer Solstice Illuminace levels (Afternoon)
The software DIVA, generated illuminance levels (lux) for the entire courtyard on a 5m by 5m grid. (Fig 2.2.1) represents the lux levels for the Summer and Winter Solstices at 9am, 12pm and 4 pm, respectively.
Fig. 2.2.1.4 Winter Solstice Illuminace levels (Afternoon)
The results show lack of built form area oriented towards the South, ensures that the courtyard remains exposed to unobstructed radiation all through the year.
Fig. 2.2.1.5 Summer Solstice Illuminace levels (Evening) Fig. 2.2.1 Illustrates the illuminance levels of the courtyard. Source: RHINO + DIVA
Fig. 2.2.1.6 Winter Solstice Illuminace levels (Evening)
Illuminance levels (lux) Scale (0 - 16000 lux)
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
2.3 Wind Study “I sit here (courtyard) while my child plays after I bring him back home from school.” - Priory Green Resident. A’
A
The prevailing winds are south westerly. The east- west orientation of the building allows unobstructed passage of the wind through the courtyard. Hence the wind flow becomes an important factor to assess the thermal comfort of the courtyard.
Fig. 2.3.1 & 2.3.2 Views of the Courtyard Source: http://www.lovelondoncouncilhousing.com/ http://kingscrossenvironment.com/
Fig. 2.3.3 Plan shows wind flow movement through the Estate. Source: FlowDesign
Fig. 2.3.4 Section AA’ shows the wind flow movement through the Estate. Source: FlowDesign
Fig. 2.3.5 Section AA’ represents the Solar Incidence on the Estate using Solstice and Equinox Sun incident angles.
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2.4 Field Work Measurements
The outdoor air temperature (fig. 2.4.1.1), air velocity (fig. 2.4.1.2), surface temperature (fig. 2.4.1.3) and illuminance levels (fig. 2.4.1.4) of the courtyard were studied by taking spot measurements in a grid of 10m by 10m. The measurements were taken on 27th October, 2015, on an overcast morning, between 8.00 and 10.30 am.
째C
Fig. 2.4.1.1 Air Temperature (째C)
m/s
Fig. 2.4.1.2 Air Velocity (m/s)
Even though the temperature difference between the various spots on the courtyard is nominal (3K) as illustrated in (fig 2.8.1), some spaces felt less comfortable than the others, due to the air velocity that ranged from 0-2.5 m/s. Thus, a possible research question that arises is- will the presence of wind buffers/barriers make the courtyard a more comfortable?
The central courtyard receives unobstructed solar radiation from the south, which can be noted in the measurements recorded in (fig. 2.8.4). It is also observed that the illuminance levels reduce as you progress from courtyard towards the buildings and other shaded spaces.
째C
Fig. 2.4.1.3 Surface Temperature (째C)
lux
Fig. 2.4.1.4 Illuminance level (lux)
Fig. 2.4.1 compiles the spot measurements of the various thermal comfort parameters
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
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INDOOR STUDIES
Air velocity : 1.0 m/s Air temp. : 14.9 °C Humidity : 66.5 % Mean radiant : 13.1 °C PET : 12.3 mPET : 16.7
1.
Air velocity : 1.5 m/s Air temp. : 16.9 °C Humidity : 67 % Mean radiant : 15.0 °C PET : 14.1 mPET : 18.2
2.
Air velocity : 0.8 m/s Air temp. : 11.4 °C Humidity : 70 % Mean radiant : 13.0 °C PET : 10.6 mPET : 14.8
2.
Air velocity : 1.9 m/s Air temp. : 16.0 °C Humidity : 68.4 % Mean radiant : 13.6 °C PET : 12.7 mPET : 17.1
3.
Air velocity : 1.5 m/s Air temp. : 14.8 °C Humidity : 69 % Mean radiant : 12.6 °C PET : 11.6 mPET : 16.3
3.
Air velocity : 1.9 m/s Air temp. : 16.2 °C Humidity : 69 % Mean radiant : 13.2 °C PET : 12.8 mPET : 17.2
4.
Air velocity : 0 m/s Air temp. : 11.6 °C Humidity : 69.8 % Mean radiant : 13.1 °C PET : 14.2 mPET : 18.8
4.
Air velocity : 2.5 m/s Air temp. : 15.7 °C Humidity : 65% Mean radiant : 13.0 °C PET : 11.1 mPET : 16.1
5.
Air velocity : 1.8 m/s Air temp. : 11.9 °C Humidity : 65 % Mean radiant : 13.0 °C PET : 8.7 mPET : 14.5
5.
Air velocity : 1.7 m/s Air temp. : 14.0 °C Humidity : 66.8 % Mean radiant : 12.6 °C PET : 10.8 mPET : 15.6
6.
Air velocity : 1.5 m/s Air temp. : 14.8 °C Humidity : 69 % Mean radiant : 12.6 °C PET : 11.6 mPET : 16.3
6.
Air velocity : 1.7 m/s Air temp. : 13.8 °C Humidity : 70% Mean radiant : 12.5 °C PET : 10.6 mPET : 15.5
8:00 -10:00
1:00 -3:00
16.0 (mPet)
16.0 (mPet)
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27th oct 17 °C | 10 °C
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1.
Fig. 2.5.1 Illustrates the range of PET values (Morning) Source: Rayman Pro
CONCLUSIONS
Fig. 2.5.2 Illustrates the range of PET values (Afternoon) Source: Rayman Pro (PET values)
2.5 COMFORT ANALYSIS 27
1.
4:00 6:00
Air velocity : 1.3 m/s Air temp. : 13.6 °C Humidity : 71.5% Mean radiant : 12.1 °C PET : 10.7 mPET : 15.6
2.
Air velocity : 0.9 m/s Air temp. : 13.6 °C Humidity : 70% Mean radiant : 12.9 °C PET : 11.3 mPET : 16.2
4.
Air velocity : 1.3 m/s Air temp. : 16.8 °C Humidity : 58 % Mean radiant : 16.3 °C PET : 14.7 mPET : 18.8
3.
Air velocity : 0.9 m/s Air temp. : 13.6 °C Humidity : 70% Mean radiant : 12.9 °C PET : 11.3 mPET : 16.2
5.
Air velocity : 1.7 m/s Air temp. : 13.8 °C Humidity : 68.6 % Mean radiant : 12.5 °C PET : 10.6 mPET : 15.5
6.
Air velocity : 2.8 m/s Air temp. : 13.5 °C Humidity : 69.4 % Mean radiant : 12.4 °C PET : 9.7 mPET : 14.4
Six spots of the courtyard were studied during various times of the day due to their varied activity pattern. The spots identified are 1 - Lawn towards the rear of the Estate 2 - Entrance of West Block 3 - Entrance of East Block 4 - Courtyard Centre 5 - Estate Entrance 6 - Pathway from Block entrance to the Estate Entrance The PET values experienced in the courtyard during the morning, afternoon and evening, respectively are calculated by observations of site activities during these times and Rayman Pro. From these studies we observed that although the courtyard is a large space within the gated community, it is used merely as a transition space, from the apartments to the outside. The courtyard is utilized to its maximum only when a few children play here, during their after school hours (4-5 pm) under adult supervision, beyond which it is largely under-utilized. These findings can be attributed to low PET values as seen in the illustrations in (Fig 2.5.1), (fig 2.5.2), (fig 2.5.3). We observed a few plausible reasons for the above stated:- lack of adequate landscaping, seating and less thermal comfort due to few wind barriers as oppposed to the park on the otherside of the street.
16.0 (mPet)
Fig. 2.5.3 Illustrates the range of PET values (Evening) Source: Rayman Pro (PET values)
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
PET - Morning :
CONCLUSIONS
Afternoon :
Evening :
PET is low, Temperatures are low, wind is unobstructed andsurface temperatures are also low, therefore this part needs to be enhanced
Fig. 2.5.6.1 View of Estate Entrance
PET - Morning :
Afternoon :
Evening :
PET is good but due to lack of seating, play infrastructure, and buffer for intermittent winds, used sparingly Fig. 2.5.4.1 View of Courtyard centre
PET - Morning :
Afternoon :
Evening :
PET is good because of good temperature, wind buffer trees, illuminance is low, but no seating or walking areas makes one of the most mutable spaces unused Fig. 2.5.5.1 View of Lawn
Vegetation, cycling path and lights are proposed to add a welcoming effect to the entrance. Fig. 2.5.6.2 Proposed View of Estate Entrance
Taking our findings from the PET calculations ahead, we propose a few changes to the current courtyard design (fig. 2.5.4.1) to (fig. 2.5.9.1) as can be seen in from (fig. 2.5.4.2) to (fig. 2.5.9.2).
Addition of Landscape and seating to improve the overall comfort. Fig. 2.5.4.2 Proposed View of Courtyard centre
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Activity based elements such as walking trails, seating and playing have been added to this unutilised green space. Fig. 2.5.5.2 Proposed View of Lawn
PET - Morning :
Afternoon :
Evening :
PET is low, wind is fairly low. Change in the material in the entrance foyer isnt making much of a difference. Fig. 2.5.7.1 View of Pathway towards Block Entrance
Re-desiging the entrance foyer, by changing the material, adding cycling paths, lights and vegetation. Fig. 2.5.7.2 Proposed View of Pathway towards Block Entrance
PET - Morning :
Afternoon :
Evening :
PET is low, wind is fairly low. Surface temperatures and illuminace are low as well. Does not act as a mediating transition space from outside to the inside. Fig. 2.5.8.1 View of Block Entrance Foyer
Addition of Vegetation to enhance the entrance foyer and using it as a mediating transition space from outside to inside. Fig. 2.5.8.2 Proposed View of Block Entrance Foyer
PET - Morning :
Afternoon :
Evening :
PET is okay but Mpet is good,considering high clo value, People are sparing seen walking. Fig. 2.5.9.1 View of Pathway from Building to Lawn
Addition of cycling paths, lights and vegetation to make the space more interative and lively. Fig. 2.5.9.2 Proposed View of Pathway from Building to Lawn
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“ From now until late February, not at all”
On being asked how often does he ventilate his house - Norman Type
“They are charged a mere £4 per week for heating. Most of them keep the radiators on even in summer.” Michael Muiriri Neighbourhood Manager
BUILDING ENVELOPE Architectural Association SED 2015-16
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
3.1 Sectional Analysis
INDOOR STUDIES U value : 1.3 W/m2 K
CONCLUSIONS
PAINTED INTERIOR 12 MM CONCRETE BLOCKS 80MM AIR GAP 50 MM EXPOSED BRICK EXTERIOR 105 MM CONCRETE BEAM ( SUPPORTS THE CANTILEVER CORRIDOR)
Figure 3.1.2 - wall section (corridor)
The building essentially comprises of two sectional details. The walls in the north and south facing walls are comprised of a section with an air gap sandwiched between two concrete walls, clad with yellow tiles. The walls facing the east and west directions consist of the air gap enclosed between a concrete wall and an exposed brick wall towards the exterior as illustrated in figures (3.1.2- 3.1.5)
U value : 1.45 W/m2 K PAINTED INTERIOR 12 MM CONCRETE BLOCKS 80MM AIR GAP 50 MM CONCRETE EXTERIOR 105 MM
The air gaps are ventilated through vents placed on the corridor side. The windows are double glazed units (figure 3.1.6) with spacers provided for increasing infiltration. 40% of the total glazing area of a single unit, opens to an angle of 30 degrees, thus mandating the necessity for infiltration to provide the requisite air change.
CERAMIC CREAM COLOUR TILED EXTERIOR 10 MM Figure 3.1.3 - wall section (north-south)
U value : 1.35 W/m2 K PAINTED INTERIOR 12 MM
However, we noticed that the occupant had his radiator for most times, which implied that without the presence of mechanical heating, the indoor temperatures were not in the comfort zone. This was seconded when we calculated the Predicted Mean Indoor temperatures (Yannas, 1991) and realised that without an additional internal gain of the radiator, the temperatures are
CONCRETE BLOCKS 80MM AIR GAP 50 MM CONCRETE EXTERIOR 105 MM CEMENT PAINTED EXTERIOR Figure 3.1.4 - wall section (staircase)
U value : 1.3 W/m2 K PAINTED INTERIOR 12 MM CONCRETE BLOCKS 80MM AIR GAP 50 MM EXPOSED BRICK EXTERIOR 105 MM Figure 3.1.1 - block plan, east block
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Figure 3.1.5- wall section (east-west)
Figure 3.1.6 - Double glazed windows and ventilators for the cavity wall
3.2 Heat loss Analysis
These observations formed the basis for our study of the difference between the indoor and the outdoor temperature. We conducted a series of spot measurements where we noted
• Surface temperatures of the interior and exteriors (below sill level) • Indoor air temperature • Difference in indoor and outdoor temperature
The figure to the left (3.2.1) states the temperature difference between the outdoor and indoor with respect to the heat losses due to the section. It was observed that the difference in the temperatures differ by orientation, for instance.
This preliminary study lead to questions of the performance of the building envelope, how the envelope conditions or affects the indoor temperature and what elements of the building contribute to the most heat losses/ gains.
Figure 3.2.1 - Plan of apartment showing heat losses through the envelope
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
3.3 Thermal Camera - Heat loss Analysis This was studied by using thermal camera pictures, to locate elements of the building through which primary heat losses were happening. The pictures also enabled us to locate any thermal bridges that were formed due to the structural details. Figures labelled (3.3.1-3.3.6) are a reflection of the same. The arrows a schematic representation of the places and nature of heat losses.
heat loss due to thermal bridge in balcony Figure 3.3.1- Thermal image - corridor
Our observations were then validated by the soft calculations the team conducted using the Energy Index (Yannas, 1991) where we gathered that due to the lack of insulation material, the air vents and the spacers in the glazing, the walls account for the largest heat losses, followed by heat loss due to ventilation needs and finally through the glazing.
Figure 3.3.1a - image of corridor
heat loss due to thermal bridge in balcony Figure 3.3.2a- image of facade
Figure 3.3.2- Thermal image - facade
Thus, these became parameters that we would look at in order to improve thermal performance Reducing heat loss through the envelope Maximising heat gains through glazing and shading devices Increasing air tightness of the building
20 C
heat loss through windows Heat gains trhough radiator
Figure 3.3.3- Thermal image - corridor
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5C Figure 3.3.3a - image of corridor
Thus, these became parameters that we would look at in order to improve thermal performance -Reducing heat loss through the envelope -Maximising heat gains through glazing and shading devices heat loss through windows/ vents
-Increasing air tightness of the building
Heat gains trhough radiator Figure 3.3.4- Thermal image - windows
Figure 3.3.4a - image of windows
heat loss through windows/ vents Heat gains trhough radiator Figure 3.3.5a- image of windows & vents
Figure 3.3.5 - thermal image - windows/vent
20 C
heat loss through windows
5C Figure 3.3.6- thermal image - windows/vent
Figure 3.3.6a - image of corridor
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“The block where I live is very close to the school and hence very noisy, especially when they play out.” - Fifth Floor Resident
INDOOR STUDIES Architectural Association SED 2015-16
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
4.1 Case study description
Norman Type’s Apartment
Apartment Type: 3 BHK Carpet Area: 78 sq.m Floor: 5th Number of Residents: 1 (Over 60 years old) Occupancy Hours: 20 Norman Type, is the only occupant of the apartment. Since, he is retired, he spends most of his time at home and hence the thermal performance of the apartment becomes critical for him. During the survey he described how much he depends on mechanical heating and artificial lighting. The residents of the estate are charged £4 a week for the centralised heating system by the Peabody Trust which does not let them hestitiate to use the radiators as often as possible. Norman likes his apartment at a standard temperature of 24 °C even during winter. He pointed out that the system is on even during the summer. So even if the individual radiators are switched off, the pipes continue leaking making the house very hot during the summers.
Figure 4.1.1 : Perspective plan of the apartment
“I put them on from September upto mid April. In some rooms they’re on all the time.” - Norman Type, on being asked how often does he put on the radiators.
The kitchen and third bedroom, open into the corridor and hence have the curtains drawn for most of the day. The corridor also provides a large overhang (1.6m) drastically reducing the daylight entering these spaces. Everytime Norman uses the kitchen, irrespective of the time of the day, he puts on the bulb. Norman, like most of the residents of the estate, uses the balcony primarily for storage. He finds the balcony “too cold and narrow” to spend time in. He balclony faces the East and hence he does not get sunlight beyond 11am. Figures 4.1.3- 4.1.4 : Pictures of the apartment
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Figures 4.1.5 : location of the apartment with respect to the estate
Figure 4.1.2 : Locating Norman’s apartment in the block
4.2 Building Typology and Occupant study
The building as alluded to earlier in the typology section, consists of one unit type as described in the previous page. Each unit is consistantly sized and there are no varying spatial configurations throughout the estate. This results in various number of occupants occupying the same space. The team investigated the occupancy patterns present in the building and if there is a correlation between the occupancy and the subsequent energy consumption. Figure (4.2.1) is a graph of percentage of occupancy types. We analysed this by simulating heating and cooling loads (figure 4.2.2) and schedules for the present occupancy types : one person, two people per apartment, three per apartment and four per apartment. We concluded that the typology that produces most heating loads is the one person occupancy and is energy inefficent thereby leading us to focus our studies on that typology. We therefore continued to investigate the house of Norman Type for further analysis.
37%
40%
21%
2%
Figure 4.2.1 : percentage of occupancy distribution 90 80 70 60 50 40 30 20 10 0 base case
2 occupant heating (kwh/sq.m)
3 occupants
4 occupants
cooling (kwh/sq.m)
Figure 4.2.2 : Heating and cooling loads for various occupancy types
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
4.3 Spot Measurements
INDOOR STUDIES
CONCLUSIONS
B A’
On the 16th of october, we took preliminary spot measures to measure relative humidity, air temperature and illuminance, between 1:30- 3:00 pm. This was done to aid in further studies about thermal performance (figures 4.3.1-4.3.2)
A
The sections below illustrate the difference between the recorded indoor temperatures and Predicted mean temepratures (figure 4.3.3-4.3.4) As depicted in the sections, most of the tempratures recorded, barring the living room (where the radiator is on most of the time) are below the comfort band.
B’ Figure 4.3.1: Relative Humidity/ Percentage(%)
16th oct 12°C | 10 °C
>70%
70-65% 65-60% 60-55% 50-55%
Figure 4.3.2 :Air Temperature / Degree Celsius(°C )
22-20 22-18 18-16 16-14 <14
16 25 24 23 22 21 20 19 18 17 16 15 14 13
RECORDED TEMPERATURE PREDICTED MEAN TEMP. COMFORT BAND
Balcony
Bedroom 1
Bedroom 2
Corridor
Figure 4.3.3 : Section AA’ depicting the predicted mean versus the recorded temperatures 25 24 23 22 21 20 19 18 17 16 15 14 13
RECORDED TEMPERATURE PREDICTED MEAN TEMP. COMFORT BAND Living Room Kitchen Corridor Figure 4.3.4 : Section BB’ depicting the predicted mean versus the recorded temperatures
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Site Plan
4.4 Data Logger Analysis We studied the data loggers to understand the activity patterns and the internal gains in normans apartment. 1.Indoor temperature does not respond to the outdoor temperature due to mechanical heating which keeps the indoor in conditions within the comfort band. The temperature pattern of the living room does not fluctuate a lot. 2.The occupant cooks food only on the weekdays (between 6am12pm). Weekends he uses the microwave. Data logger shows higher internal gains on weekends. 3.The building envelope can be modified to a free-running building by upgrading the insulation. Predicted mean indoor temperature has been calculated without any mechanical heating energy. 4.The living room shows peaks in temperature at around 12am. The inconsistency can be attributed to the cycle of the heating system. 5. The balcony does not aid in creating thermally comfortable indoor spaces. The approx.∆Tbal –out= 0.75 – 1.5K The approx.∆Tin –bal= 0 – 4K 6. Balcony – Used for storage purposes. The temperature pattern of the balcony remains consistent with the outdoor.
Figure 4.4.2 : Graph showing living, kitchen, balcony and outdoor temperatures of Norman Type’s house (Source : TinyTag software)
Air Temperature - LIVING
Air Temperature - KITCHEN
Air Temperature - Outdoor Temperature
Air Temperature - BALCONY
Predicted Mean Indoor Temperature - LIVING Figure 4.4.2 : Data logger positions in Normans apartment
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
B
4.5 Iluminance analysis
A’
On the 16th of october, we took preliminary spot measures to measure relative humidity, air temperature and illuminance, between 1:30- 3:00 pm.
A
The plan illustrated in figure (4.5.1) shows the spot measurments taken for illuminance levels in Norman Type’s apartment. The measures were taken at sill level. We noticed that the occupant had artificial lighting on even in the afternoon. Upon looking at the spot measurements, we noted the lux levels were very low.
B’ Figure 4.5.1 : Illumimance / Lux Levels ( LUX)
In order to study this further we looked at differing tools to help us understand :
0500 500 1000
-the role of orientation in the amount of daylighting
1000 - 1500 - 2000 - 2500 - >3000 1500 2000 2500 3000
-the daylight factor of the space -the impact of the window/floor ratio and percentage of glazing on administrating RECORDED LUX
16th oct 17 °C | 10 °C
16
Balcony
Bedroom 1
Bedroom 2
Corridor
Figure 4.5.2 :Section AA’ showing the Lux levels
Living Room Kitchen Figure 4.5.3 :Section BB’ showing the Lux levels
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Corridor Site Plan
21st March (Summer Solstice)
4.6 Sunpath studies Impact of Orientation on daylighting The sunpath studies using RHINO with Grasshopper helped us understand the daylighting pattern with respect to solar hours. The orientation of the building (East-West) decided the duration for which each space of the apartment received daylighting. Figure 4.6.1 :Sunpath in march East facing (morning) (source : RHINO + ladybug)
Figure 4.6.4 :Sunpath in march, West facing (evening) (source : RHINO + ladybug)
21st June (Summer Equinox)
Figure 4.6.2 :Sunpath in June, East facing (morning) (source : RHINO + ladybug)
Figure 4.6.5 :Sunpath in June, West facing (evening) (source : RHINO+ ladybug)
22nd December (Winter Equinox)
Figure 4.6.3 :Sunpath in December, East facing (morning) (source : rhino + lady)
Figure 4.6.6 :Sunpath in December, West facing (evening) (source : RHINO + ladybug)
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS 4.7
4.7 Window to floor ratio analysis
1.2
Upon studying the effects of orientation, we studied the window to floor ratio in order to understand the depth upto which light enters a space. Using the angle of incidence of the sun during summer, winter solstices and equinox, the team investigated how structural features like area of glazing, presence of overhangs, height of parapets and spatial configuration play a role in admittance of daylighting. Kitchen
Through this, we inferred that except the living room no other space gets sufficient daylight, while the bedrooms remain poorly lit, despite the fact that the window to floor ratio is greater than the living. This can be accounted for by the presence of large overhangs. The location of the master bedroom makes it incident to indirect daylight for most times of the year.
Corridor
Living room
Bedroom 2
Master Bedroom
Balcony
3.5
This was further investigated for an annual understanding in the next section.
1.0
Figure 4.7.1 :Section studying solar incident angles – East Facade
1.2
Window to Floor Ratio
Living room
1.2
Figures (4.7.1-4.7.2 ) illustrate through sections the solar incidence angles at various times of the year.
: 25.5% - No overhang
Summer Solstice 16 ° Equinox
39 °
Winter Solstice
62 °
Kitchen
Living room
Bedroom 2
Master Bedroom
1.2
Master Bedroom : 34.3% - 1.0 m overhang & Study Kitchen : 38.7% - 1.6m overhang
Corridor
1.6
3.1 Figure 4.7.2 : Section studying solar incident angles –
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Balcony
4.8 Daylight autonomy study In order to study the amount of daylight the apartment receives throughout the year, we modulated illuminance maps as shown in figures (4.8.1-4.8.4) of the apartment through various times of the year, namely the summer and the winter solstices and annually as well. We modeled these simulations for both overcast and sunny conditions and Using the DIVA software, we generated ‘Daysim’ reports which informs of the daylight factor According to the CIBSE Lighting Guide 10, which broadly bands average daylight factors can be put into the following categories: Under 2 – Not adequately lit – artificial lighting is required figure 4.8.1 :Illuminance Map of the apartment Summer Solstice , 12pm, Overcast day (source : Rhino +DIVA)
Figure 4.8.2 : Illuminance Map of the apartment Summer Solstice , 12pm, Sunny day (source : Rhino +DIVA)
Between 2 and 5 – Adequately lit but artificial lighting may be needed part of the time Over 5 – Well lit – artificial lighting generally not required, but glare and solar gain may cause problems The findings of these simulations illustrated that the Daylight factor for the entire apartment was about 2.1 %. While the kitchen and master bedroom has daylight factors below 2.1 %, the daylight factor in the living room was 4.6%. However, due to the orientation impacts as discussed in the previous section, no part of the apartment gets 250 Lux for a minimum of 50% of the day, over 50% of the area - a standard defined by ‘DAYSIM for residences.
Figure 4.8.3 :Illuminance Map of the apartment (source : Rhino +DIVA)
Figure 4.8.4 : Illuminance Map of the apartment (source : Rhino +DIVA)
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
4.9 Interior Illuminance Studies
Figure 4.9.1 : Kitchen
Figure 4.9.2 : Living Room
Figures 4.9.1 to 4.9.3 show various rooms in the apartment that are to be studied for their illuminance levels. In order to understand the incident daylight in the space as well as the glazing unit that supplies this daylight, we simulated false colour images (figures 4.9.4 - 4.9.9) displaying lux levels in the room. This coupled with the illuminance maps that preceeded this page, we are able to discern how much daylighting the various rooms in the space recieve. The renders enabled us to also notice if the illuminance is sufficient for the nature of space, i.e, if there is enough daylight on the platform in the kitchen or if there is enough daylight on the working table in the living room. Through these images, we were able to validate the necessity for increasing daylighting.
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Figure 4.9.3 : Master bedroom
CONCLUSIONS
Figure 4.9.4 :Kitchen_Summer Solstice , 12pm, Over Cast sky (source : DIVA)
Figure 4.9.4 :Living room_Summer Solstice , 12pm, Over Cast (source : DIVA)
Figure 4.9.4 :Master Bedroom_Summer Solstice , 12pm, Over Cast (source : DIVA)
Figure 4.9.4 : Kitchen_Winter Solstice , 12pm, Over Cast sky (source : DIVA)
Figure 4.9.4 : Living room_Winter Solstice , 12pm, Over Cast (source : DIVA)
Figure 4.9.4 :Master Bedroom_Winter Solstice , 12pm, Over Cast (source : DIVA)
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
5.0 Base Case Thermal simulations ORIGINAL CONDITIONS (BASE CASE) 80 mm Concrete wall Air gap (50 mm) Brick wall (105 mm)
Figure 5.0.1 : Base case
WALL SECTION U VALUE : 1.45 W/m2 K : 1.3 W/m2 K
After studying the existing case. we established it as a base case to conduct further studies on. Through the previous studies, we concluded that thermal performance can be improved by reducing heat losses through the walls, making the apartment more air tight and reducing losses through the windows. We studied the heat gains and losses in the existing case and began to change various factors in the existing case to simulate the impact these changes have on heating and cooling loadsse.
GLAZING UNIT U VALUE : 2.9 W/m2 K
IMPROVING THE ENVELOPE
80 mm Concrete wall Insulation Brick wall (105 mm)
Figure 5.0.3 : Improved base case with insulation
WALL SECTION U VALUE : 0.33 W/m2 K :0.33 W/m2 K GLAZING UNIT U VALUE : 1.3 W/m2 K
Figure (5.0.1 ) illustrates the base case with its current sections and their respective U values. Figure (5.0.2 ) is a chart for the internal gains and figure (5.0.3) is a graph for heat los and heat gains 0.6 mean Wh 43.8 mean Wh
125 mean Wh
The various parameters applied in order to reduce heating and cooling loads from the base case to the improved case are listed as follows :
0.6 mean Wh
85 Kwh/sq.m
U value of wall section changed from 1.45 and 1.3 to 0.33, by adding a layer of insulation to lessen heat losses through the walls.
275 mean Wh 250 mean Wh 194 Kwh/sq.m
131 Kwh/sq.m
HEAT LOSS THROUGH WINDOWS HEAT LOSS THROUGH WALLS HEAT LOSS THROUGH VENTILATION
12.5 mean Wh 44 Kwh/sq.m
20.8 mean Wh
32 Kwh/sq.m
INTERNAL HEAT GAINS SOLAR HEAT GAINS
2.5 mean Wh
Figure 5.0.2 : Internal heat gains, appliances for Norman Type’s house
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U value of double glazed unit improved from 2.9 to 1.3
Figure 5.0.2 : Heat loss and heat gains for Norman Type’s house (source : Energy Index)
Reducing cooling loads by introducing set temperature ventilation provision
Rest of the apartment temp
Master bed temp
Outdoor temp.
Living indoor temp.
Study bed. temp.
Comfort band
Figure (5.0.4) is the annual graph for indoor temperatures for the base case. It clearly demonstrates the necessity for applying insulation and cooling as a very large portion of the operative temperatures fall either lower or higher than the comfort band. Figure 5.0.4 : Graph showing indoor temperature of the base case (source : EnergyPlus + Openstudio)
Figure (5.0.5) is the improved case where insulation, night shutters and temperature driven ventilation is applied.
The improved case demonstrates most of the operative indoor temperatures falling within the comfort zone.
JANUARY
FEBRUARY
MARCH
APRIL
MAY
JUNE
JULY
AUGUST
SEPTEMBER
OCTOBER
NOVEMBER
DECEMBER
Figure 5.0.5 : Graph showing indoor temperature of the improved base case with ventilation and insulation (source : EnergyPlus + Openstudio)
Solar Radiation
Infiltration
Outdoor temp.
Indoor Temp.
Comfort band
Heating required
cooling through Natural ventilation
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
Solar Radiation
Solar Radiation
Infiltration
Infiltration
Outdoor temp.
Outdoor temp.
Indoor Temp.
Indoor Temp.
Figure 5.0.6 : indoor temperature in improved case during winter week (18th june to 24th june)
Figure 5.0.7 : indoor temperature in improved case during a typical winter week (29th jan to 2nd feb)
Figure (5.0.6) is a graph showing the operative indoor temperatures in the improved case during a typical summer week Figure (5.0.7) is a graph showing the operative indoor temperatures in the improved case during a typical winter week The heating and cooling loads for the various modulations from the base case to the improved case show a substantial decrease in heating loads, However, the cooling demand has increased due to the added air tightness. Thus, we take this idea of improving thermal performance by addressing heat losses though the envelope further as we Figure 5.0.8 : Heating and cooling loads (annual) for various parameters applied to Base case towards the improved case
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CONCLUSIONS
5.1 Balcony Studies
Guided by observations on site, we noticed that despite the fact that the balcony accounts for almost ___ % of the area, it is a largely underutilized space. Occupants were generally seen using it for storage purposes as illustrated in figures (5.1.1 and 5.1.1a) We began to investigate the possible reasoning for this. The reasons contributed by the occupant was the minimal width (1.2 m), the high parapet wall that restricts view and a pertinent commentary on the thermal comfort of the space
“Why would I go there? It’s so cold and beyond 11am, I barely get any warmth from the sun, since my balcony faces the east” (on being asked why he doesn’t use the balcony much) To validate these observations, we calculated the Physiological Equivalent Temperature (PET) and the mPET in three different locations - the courtyard, the corridor and the balcony, to understand the relative comfort in the each of these locations. This is illustrated in figure (5.1.2) to show the varying degrees of comfort from the outside, through the corridor, to the balcony. We assumed differing clo values for each case2.5, 2.5 and 1.3 for the courtyard, corridor and the balcony respectively. The calculations confirmed that the balcony is not a favourable space, with a low thermal comfort.
Figure 5.1.1 : Images showing balcony spaces used for storage purposes
Figure 5.1.1a : Images showing balcony spaces used for storage purposes Figure 5.1.2 : Schematic section of a block to show relative comforts in three places - the indoors, the courtyard, the balcony and the corridor
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
This prompted us to rethink the spatial configuration of balcony, in a way that contributes to the thermal performance of the apartment and ceases to be an underutilized space. Using the existing case as a base, we manipulated factors like total glazing percentage, window to floor ratio to generate various cases, which were then studied for their thermal performance. This parametric study is illustrated (figures 5.1.3-5.1.3e) below
BASE CASE Current Apartment Unit
CASE 3 Glazed Balcony
WINDOW/ FLOOR RATIO - 1.16
WINDOW/ FLOOR RATIO - 2.61
GLAZING PERCENTAGE - 13.4%
Figure 5.1.3 - Base case for balcony modulation
GLAZING PERCENTAGE - 22.4%
Figure 5.1.3c - Case 3 for balcony modulation
CASE 1 Glazed Balcony with french windows in bedroom.
CASE 4 Balcony included in the bedroom WINDOW/ FLOOR RATIO - 1.6
WINDOW/ FLOOR RATIO - 3.19
GLAZING PERCENTAGE - 22.4%
GLAZING PERCENTAGE - 28.4%
Figure 5.1.3d - Case 4 for balcony modulation
Figure 5.1.3a - Case 1 for balcony modulation
CASE 2 Fully glazed balcony with french window in living room
CASE 5 Balcony as a sunspace
WINDOW/ FLOOR RATIO - 4.7
WINDOW/ FLOOR RATIO - 4.5
GLAZING PERCENTAGE - 39.2%
Figure 5.1.3b - Case 2 for balcony modulation
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GLAZING PERCENTAGE - 39.2% Figure 5.1.3e - Case 5 for balcony modulation
After studying the various cases, we compared the annual heating and cooling loads of each case against the base case to understand the comparative impact produced. The graph (figure ) illustrates the mean indoor temperature of the living room in each of the cases, to see if the indoor temperatures produced fall under the comfort band.
The cases, referred to as case 1 and case 2 hereafter, are then dealt with in the subsequent sections by applying various parameters affecting the heat loss through envelope, considered in the previous section, to further investigate the cases.
The simulations as generated on OpenStudio were made without applying the thermostat, to gauge the potential of each these parametric studies into drastically reducing heating and cooling loads, with the intention of becoming free-running. Upon analysis, we picked two cases to study further, based on the following factors : • minimum and maximum intervention to the existing fabric • significant reduction in heating loads • cases that offer greater occupant adaptive opportunity Figure 5.1.4 : Annual heating and cooling loads for each of the balcony cases to assess thermal performance
JANUARY
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MARCH
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JUNE
JULY
AUGUST
SEPTEMBER
OCTOBER
NOVEMBER
DECEMBER
Figure 5.1.5 : Annual operative indoor living room temperatures for each of the balcony cases
Solar Radiation
Outdoor temp.
Base case indoor temp
case 1 indoor temp
case 2 indoor temp
case 3 indoor temp
case 4 indoor temp
case 5 indoor temp
Comfort band
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
Case 1 with improvements : - U value of 0.33 W/m2 K for the wall section with added insulation
-U value of 1.3 W/m2 K for double glazing -added temperature set ventilation schedule -added night shutters (from 9 pm to 6 am)
Figure 5.1.7 - Simulation for typical winter week for case 1, improved (source: EnergyPlus with Openstudio)
Figure 5.1.6 - Simulation for typical summer week for case 1, improved (source: EnergyPlus with Openstudio)
JANUARY
FEBRUARY
MARCH
APRIL
MAY
JUNE
JULY
AUGUST
SEPTEMBER
OCTOBER
Figure 5.1.8 - Graph showing indoor temperature of the improved case 1 with ventilation and insulation (source : EnergyPlus + Openstudio)
Solar Radiation
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Infiltration
Outdoor temp.
Indoor Temp.
Comfort band
Heating required
cooling through Natural ventilation
NOVEMBER
DECEMBER
Case 2 with improvements : - U value of 0.33 W/m2 K for the wall section with added insulation
-U value of 1.3 W/m2 K for double glazing -added temperature set ventilation schedule -added night shutters (from 9 pm to 6 am)
Figure 5.1.10 - Simulation for typical winter week for case 2, improved (source: EnergyPlus with Openstudio)
Figure 5.1.9 - Simulation for typical summer week for case 2, improved (source: EnergyPlus with Openstudio)
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OCTOBER
NOVEMBER
DECEMBER
Figure 5.1.11 - Graph showing indoor temperature of the improved case 2 with ventilation and insulation (source : EnergyPlus + Openstudio) Solar Radiation
Infiltration
Outdoor temp.
Indoor Temp.
Comfort band
Heating required
cooling through Natural ventilation
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OVERVIEW
OUTDOOR STUDIES
BUILDING ENVELOPE
INDOOR STUDIES
CONCLUSIONS
Conclusions Indoor conclusions The building being an old estate, uses the leakiness in its structure to account for air changes. However, due to the same reason, it becomes susceptible to large heat losses from the envelope. Improvements made in the envelope by adding insulation and increasing air tightness reduces cooling loads significantly, but beyond a point, the insulation stops being effective and starts contributing to an increased cooling load. In order to mitigate that, provisions for occupant adaptive control must be provided. For instance, the current window unit has a very small effective opening aperture. By allowing for natural ventilation to mitigate the effects of increased cooling load, as per adaptive opportunities of the occupant, energy consumption can be checked. Carrying the same thread from the previous point, it is noted that the radiators that operate in Priory, function through communal heating. Even if a resident were to shut the radiator off, the hot water flowing through the pipes continue to heat the space undesirably. Due to this lack of sufficient control, the apartments end up getting overheated during summers. Provisions for a system where the occupant can exercise greater control would be more efficient. As the typology is uniform throughout the estate, offering the same apartment for various patterns of occupants, the internal heat gains are not taken advantage of to tackle heating loads, in cases of 1 or 2 persons per flat. Varying apartment types to optimize heat gains, would make the apartments more efficient. Due to the fact that the balcony is spatially and thermally uncomfortable, it is seldom used. And as observed in the parametric cases in the indoor section, the indoor operative temperature for the case with no balcony and a glazed balcony are nearly the same. Thereby leading to the conclusion that, the balcony could be included in the apartment space or the effective glazing percentage could be increased to make it contribute to reducing the heating loads and increasing daylighting.
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Outdoor conclusions The courtyard has good PET values, but due to the lack of adequate landscaping (i.e trees acting as wind buffers) and seating, it is not used very often by the residents, barring for children in evening. In order to improve this, landscaping and seating need to be added to improve the overall comfort, keeping the activities in mind. The landscaped area in the rear end, displays good temperatures and low wind velocities, but this area is entirely unused due to lack of any assigned activity (no seats or walking trails or play areas) Addition of activity based elements will make use of these spaces. The design of outdoor spaces should be done keeping the occupancy patterns in mind, in order not to create spaces that are rarely used. ‘Comfort scales’ like PET and mPET are effective tools in establishing spots that can become favourites by the users. A variety of ‘thermally comfortable places’, provided by manipulating surface temperatures, landscaped features, wind buffers etc, can create a well functioning outdoor space that accounts for various users, thereby avoiding creating thermally monotonous spaces.
The project provided us the opportunity to learn some very different tools from what we were used to. Through the means of various software, we could simulate and understand the effect of each parameter that plays a role in the environmental performance of a building. Documenting of the climatic conditions of the outdoor and the indoor at site, gave us an idea of how to place ourselves to deal with pressing concerns of energy consumption and introduced us to the idea of free-running. I particularly enjoyed engaging with the occupants in order to find their “favorite” spots and how that translated into design features was a very enriching and informative experience. We were lucky enough to meet Norman, someone who has lived in Priory Green all his life and thereby we were able to get some very keen insights about the performance of the building, it’s growth and its transformation over fifty years. I’m hopeful that this knowledge will enable me with more tools to design better for the terms to come. -Anusha Nanavati
The study of performance of a high density residential complex with respect to its surroundings, climate and occupants was a valuable opportunity, that has changed my understanding of sustainable design. It was interesting to learn the evolution of the locale with respect to Lubetkin’s original intention to provide better quality affordable social housing, and transformation of the structure from pre-war design (1930s) to the current situation. However along with time, estate had unfortunately fallen into a very rundown state, some initiatives were taken to revitalise it. But there is still more room for improvement which we have identified through our field studies and numerous discussions along the term. Although the architect paid particular attention to the transition from outside to the individual units, the open spaces are not used as expected due to the lack of thermal comfort and designated functional spaces. Poor performance of the building envelope and lack of adaptive opportunities for controlling the heating system and ventilation has lead to over consumption of energy. The analysis of field measurements and simulation results has helped us to make proposals including improved courtyard landscape, adaptive ventilation strategies, better performing envelope and transitional spaces for energy efficiency and well being of the residents. I have come to realize how a building’s form, orientation, services and materials used are critical for occupant comfort. This holistic approach to sustainability concepts has widened my perspective of design. -Thajnu Rashid
This project was the best way to inch into the concept of what sustainable design is. Understanding various tools deployed to predict environmental factors was very interesting as it made the theoretical concepts of energy consumption, reducing heating and cooling loads and free-running almost life-like. Interacting with the occupants of the Priory Green was an engaging experience as it led to a thorough understanding of what the end user desires from an architect in terms of a space and how as an architect, it becomes essential to communicate this idea of sustainability to them. Working with the team in order to simulate various situations was extremely interesting as various thought processes were shared and exchanged during the process. Each one helped the other in fields of their own “growing comfort and expertise”. It was interesting to see a building from the 50s become relevant to today’s scene again, giving a new notion to the idea of refurbishment and adaptive usage. Constantly working with and on site and assessing the comforts for ourselves, I was able to be a part of the study too. At the back of my head, I would compare it to the social housing at home, eager to translate the learning from this study to various scenarios. I look forward to implementing not just the tools I’ve gained, but the new methodology and scope of thinking that I’ve learnt through this exchange.
“The best way to learn is to do” -Paul Halmos Working with London as a “live laboratory” through the duration of this project, to understand the principles of Sustainable Environmental Design, has been an excellent experience. Applying the theories that were introduced to us every week to a real life scenario and understanding how simple and adaptive strategies can go a long way in reducing energy consumption has given me a greater sense of confidence towards the practice of passive design. What excited me about the site, Priory Green Estate, was its historical context and the opportunity it provided to meet residents who has occupied the building for a duration of 40 to 2 years. Each one had their own unique way of responding to the conditions of the Estate. The insights of orientation of the built-form and facade section that responds to the orientation that I have seen while working on this project have made my concepts on the subject very clear. It was interesting to work in a team four, where even though we are from the same country, we came from very different schools of thoughts. We have learnt alot from each other in terms of methodology, presentation and teamwork. I look forward to applying the learnings from this term into the next project and the future.
-Shruti Shiva
Architectural Association SED 2015-16
-Trishta B Vardhan
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