AA SED_MSc Dissertations by AA School

dissertation projects Architectural Association / School of Architecture / Graduate School MASTER OF SCIENCE in Sustainable Environmental Design

http://sed.aaschool.ac.uk

Architectural Association / Graduate School MSc Sustainable Environmental Design

MSc SED dissertation projects Sustainable environmental design engages with real-life problems affecting buildings and cities throughout the world. Providing alternatives to the global architecture and brute force engineering that are still the norm in most countries requires new knowledge on what makes a good environment for inhabitants and how architecture can contribute to this. Over the past five years the AA School’s SED Programme has pursued a research agenda on “Refurbishing the City”, initiating projects in some 70 cities across 40 countries and encompassing a wide range of building types and climates with proposals for both new and existing buildings and urban spaces. The 12-month MSc is structured in two consecutive phases. Phase I is organised around studio projects that are run in teams combining MSc and MArch students (see books on Term 1 Urban Case Studies and Term 2 Design Projects). Studio projects are supported by weekly lectures, software workshops and tutorials. The research methods introduced by the taught programme combine on-site observations and measurements with advanced computational simulation of environmental processes. Phase II is devoted to Dissertation Projects focusing on areas of design research that address the programme’s areas of concern as well as students own backgrounds, professional interests and special skills. Key objectives of all projects are to improve outdoor environmental conditions in cities, achieve independence from non-renewable energy sources in buildings and promote the development of an environmentally-sustainable architecture. The excerpts included in this compilation are from a selection of recent MSc Dissertations illustrating the climatic, typological and thematic diversity of projects undertaken for the Master of Science in Sustainable Environmental Design. Simos Yannas, Director MSc & MArch Sustainable Environmental Design

the amazon research network:

social housing in Costa Rica

lessons from the Masters

sustainable architecture for the tropical rainforest

strategies and consideration for passive design

a study of Tertiary Educational Buildings in India

September 2011 Alexandre Hepner

September 2008 Michael Smith Masis

September 2013 Megha Nanaiah

creative refurbishment of historic housing

Keeping the Nomad

refurbishing the city a.urban canyon b.urban block c.arcade

September 2013 Anastasia Gravani Eleni Kaltsogianni Byron Mardas

in Santiago de Compostela

September 2011 Patricia Linares

adaptive bedouin house in Wadi Rum

September 2013 Rawan Qobrosi

climatic adaptation of the office building typology in the Mediterranean September 2013 Jonathan Natanian

Architectural Association / Graduate School MSc Sustainable Environmental Design

MSc SED dissertation projects

table of contents

Architectural Association / Graduate School MSc Sustainable Environmental Design

MSc SED dissertation projects

the amazon research network: sustainable architecture for the tropical rainforest

September 2011 Alexandre Hepner

The Amazon Research Network Chapter 3

3.1.2 Provision of energy and management of resources 4.1.1.1 Local processes: solar and wind energy, water treatment 4.1.1.2 Systemic processes: biodigestion, waste treatment Fig. 3.5. Energy matrix of the Amazon Research Network. As a self‐sustaining system, the Amazon Research Network should supply its own energy to meet the demand of all its components. This need comes not only from the environmental ideology that guides the project, but also from the fact that, being dispersed in a wide territory and in remote locations, most of its facilities are disconnected from the energy grid. Considering the delicate environmental context of the Amazon Forest, the use of conventional modes of energy production based on fossil fuels must be pre‐emptively discarded in favour of alternative solutions based on renewable resources. In order to establish an energy matrix for the network, it is necessary to identify which resources are available in the Amazon and which are the specific needs put forward by the system. Initially, four potential sources of energy can be identified: solar radiation, wind energy, the kinetic energy of the river currents, and biomass. Each of these must be processed in different ways in order to be taken advantage of (Fig. 3.5) As for the specific needs of the system, they differ in the case of the research stations and the mobile units. The research stations would basically need electric energy in order to power up common electrical appliances, computers and other kind of equipments that integrate the laboratories. While some of these technical equipments could be relatively energy intensive, this should not be complicated to provide

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3.1 The Network

Fig. 3.2. The research stations can be upgraded to higher ‘levels’ according to how many other stations they are connected to.

3.1.1 The dynamic arrangement of the system ESQUEMA NIVEIS Fig. 3.1. Relation between fixed research stations and mobile research units. Each pair of ‘connected’ stations is serviced by three mobile units.

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Chapter 3

Fig. 3.3. Schematic diagram of the possible evolution of the Amazon Research Network over time. 39

AA E+E Environment & Energy Studies Programme Architectural Association School of Architecture

3.2.2 Boat design

Fig. 3.9. Comparison between lateral stability in ‘displacement’ boats and catamarans

It is not the purpose of the present study to discuss about t particularities of boat design, especially considering that, although t mobile unit is a floating platform, it is not to be regarded as a bo because its primary function is not that of transportation.

Fig. 3.10. The two‐hulled catamaran is one of the lightest models of boats.

Fig. 3.11. Elevated decks in catamarans allow better heat dissipation through convection.

Nevertheless, energy saving is one of the key issues sustainable environmental design, and as such should be consider from all perspectives. It would stand as a fundamental contradiction Fig. 3.9. Comparison between lateral stability in ‘displacement’ boats and catamarans. achieve environmental comfort through passive means in a mobile un It is not the purpose of the present study to discuss about the if this same unit would in the other hand require significant amounts particularities of boat design, especially considering that, although the energy to unit be is moved. The same it resources could rather mobile a floating platform, is not to be regarded as a be boat spent f because its primary function is not that of transportation. providing air‐conditioning for an efficient boat, and this is exactly t situation that should be avoided. For this reason, some attention will Nevertheless, energy saving is one of the key issues of given to the fundamentals of boat design. sustainable environmental design, and as such should be considered from all perspectives. It would stand as a fundamental contradiction to

achieve environmental comfort through passive means in a mobile unit, In the case of the mobile units, efficiency is not particula related to speed capacity as it is in general boat design. As a matter if this same unit would in the other hand require significant amounts of energy be not moved. The resources could rather be to spent do for so witho fact, they to do need to same move fast, but they need providing air‐conditioning for an efficient boat, and this is exactly the spending much energy, and in this case lightness and reduced resistan situation that should be avoided. For this reason, some attention will be to water are central issues. given to the fundamentals of boat design.

Regular boats which do not fall into special categories – such In the case of the mobile units, efficiency is not particularly related to speed capacity as it is in general boat design. As a matter of the narrow ‘cutters’, which cut through water, or shallow ‘sloops’, whi fact, they the do surface not need of to water move fast, but often they need to ‘displacement’ do so without boa slide over – are called spending much energy, and in this case lightness and reduced resistance because they achieve lateral stability by displacing water to the sid to water are central issues. (Doane, 2010). In order to do so, they need to counterbalance t weight of Regular boats which do not fall into special categories – such as water by simply being heavy, or using additional ballast the narrow ‘cutters’, which cut through water, or shallow ‘sloops’, which increment their weight. This makes this type of boat boats heavier th slide over the surface of water – are often called ‘displacement’ boats, they need to be, and intrinsically less efficient (Fig. 3.9). because they achieve lateral stability by displacing water to the sides (Doane, 2010). In order to do so, they need to counterbalance the

Fig. 3.12. Elevated decks in catamarans also contribute for greater exposure to wind. Fig. 3.12. Elevated decks in catamarans also contribute for greater exposure to wind.

weight One special type of boat known as ‘catamaran’ achieves late of water by simply being heavy, or using additional ballast to stability through its geometry rather than through its weight, allowing increment their weight. This makes this type of boat boats heavier than to they need to be, and intrinsically less efficient (Fig. 3.9). be much lighter than other types (Fig. 3.10). The catamaran basically a One special type of boat known as ‘catamaran’ achieves lateral boat with two hulls united by a platform that stands abo the stability through its geometry rather than through its weight, allowing it level of the water, considerably increasing the usable area of t to be much lighter than other types (Fig. 3.10). The catamaran is boat without increasing its friction with the water. For this two reasons basically and a boat with two hulls united by a that stands represents above lightness increased usable area – platform the catamaran t the level of the water, considerably increasing the usable area of the perfect model for the mobile unit.

boat without increasing its friction with the water. For this two reasons – lightness and increased usable area – the catamaran represents the The catamaran also possesses several other characteristics th perfect model for the mobile unit.

Fig. 3.13. The space between the two hulls Fig. 3.13. The space between the two hulls creates pressure differences that can be creates pressure differences that can be taken advantage of for cross ventilation. taken advantage of for cross ventilation.

can be taken advantage of from the point of view of passive design. Fi The catamaran also possesses several other characteristics that of all, its elevated deck allows better heat dissipation throu can be taken advantage of from the point of view of passive design. First convection, because it is ventilated from above and below rather th of all, its elevated deck allows better heat dissipation through just convection, from above like it other boats from (Fig. 3.11). catamarans al because is ventilated above and Because below rather than tend to be ‘taller’ than other boats, its deck enjoys greater exposure just from above like other boats (Fig. 3.11). Because catamarans also tend to be ‘taller’ than other boats, its deck enjoys greater exposure to wind because it can be higher than surrounding obstacles (Fig. 3.1 wind because it can be higher than surrounding obstacles (Fig. 3.12). Finally, the two‐hulled shape of the catamaran creates areas of pressu Finally, the two‐hulled shape of the catamaran creates areas of pressure difference in‐between the two hulls that can contribute for efficie difference in‐between the two hulls that can contribute for efficient cross ventilation (Fig. 3.13). cross ventilation (Fig. 3.13).

AA E+E Environment & Energy Studies Programme Architectural Association School of Architecture

3.3.3 Mobile units ‐ architectural design FLOOR PLAN

LATERAL ELEVATION

FRONT ELEVATION Fig. 3.15. Architectural design of the mobile research units.

The Amazon Research Network Chapter 3

3.3.4 Construction The mobile research unit is built with modular lightweight components. Its primary structure is made of steel in order to provide greater structural stability, and a secondary wood structure holds the wood hull panels in place. Operable façade components offer adaptive possibilities for solar and ventilation control. Each of the two sides of the catamaran is occupied by a group of three ‘lab pods’ and three bedrooms fitted with bulk beds, accommodating in total a crew of up to 12. The central deck holds the control station, office, kitchen and main social area of the mobile unit, which can be used for several different purposes.

Fig. 3.16. Construction scheme of the mobile research units. 49

The Amazon Research Network Chapter 3

3.3.6. Solar control The lower part of the exterior side walls are closed by ‘muxarabi’ panels that allow permanent ventilation, combined with movable mosquito screens on the inner side. The windows are top hinged and have operable louvers, allowing adaptive control of lighting and natural ventilation to suit the occupier’s needs.

Fig. 3.19 Adaptive façade components and solar control

3.3.7 Natural lighting

Dayligh is abundantly available, because the natural shape of the catamaran generates a shallow floor plan, increasing the ‘passive area’ of natural lighting. There are many openings to the outside which can be controlled in order to reduce illumination and avoid glare in case there is need to.

The parts that enjoy the most natural lighting are the front flanks of the hull, where the ‘lab pods’ are located. This is consistent with their use as the main work areas of the mobile unit. However, even the innermost area of the boat still enjoys very good lighting, with a daylight factor of at least 10%.

Fig. 3.20 Average daylight factor in the mobile research unit

AA E+E Environment & Energy Studies Programme Architectural Association School of Architecture

3.3.8 Natural ventilation Natural ventilation is of extreme importance in order to provide comfort cooling for the occupants of the mobile unit. Constant air movement is extremely desirable, and therefore strategies were developed in order to promote cross ventilation as much as possible.

Even if occupiers in one side of the boat desire to close their windows, occupiers on the other side may still profit from cross ventilation through the permanent openings oriented to the ‘inner courtyard’ of the catamaran.

The envelope of the boat is very permeable to wind, and it can be adapted by the occupiers by opening windows and regulating louvers in order to allow more or less light and air in (Fig. 3.21).

Computer Fluid Dynamics (CFD) simulations were made using the softwares WinAir and Ecotect in order to assess if the natural ventilation is occurring as efficiently as desired and to identify possible problems.

b Fig. 3.21. Possible modes of ventilation: a) Through open windows; b) Through muxarabi panels louvers; c) Cross ventilation across the ‘inner courtyard’ of the catamaran

Fig. 3.22. CFD simulation, longitudinal cross‐section of the catamaran. Although the sails can cause significant turbulence around the boat by offering resistance to the wind, air movement is still kept close to the original speed of incoming wind (100%) across the interior of the boat because the sails are leeward (behind) of the aft (back) openings. 52

a b

The Amazon Research Network Chapter 3

Fig. 3.25. The mobile units can perform long research missions that could take up to a week.

Fig. 3.26. Central deck of the mobile research unit. 55

AA E+E Environment & Energy Studies Programme Architectural Association School of Architecture

3.3.1 Components Fig. 3.29. Structural components of a Level 1 research station.

The research stations are basically composed by two parts: a circular ‘core’ organized around the biodigester plant, and a linear ‘research wing’ stretching out towards the water of a river. This wing branches out in three docks that can receive one mobile unit each. The core has two floors, with the ground floor housing the research and working facilities and the upper floor accommodating the staff’s living quarters. The research wing, in turn, offers both bedrooms and laboratories for the mobile unit’s crews. The structure of the core part is made of modular steel components because of the large space they enclose, while the research wing has a simple wood structure.

The Amazon Research Network Chapter 3

Fig. 3.32. Research station – Upper floor plan.

Fig. 3.33. Research station – Front elevation.

Fig. 3.33. Research station – longitudinal section.

AA E+E Environment & Energy Studies Programme Architectural Association School of Architecture

3.3.5 Natural ventilation Natural ventilation as form‐finding

Fig. 3.40. Expected natural ventilation scheme for the research station: a) roof openings on the upwind side act as ‘wind scoops’, drawing ventilation in; b) ‘wind cowl’ on the centre of the core roof promotes buoyancy exhaust;

c) roof openings on the downwind side promote further exhaust, as the ‘stepping down’ shape of the roof creates areas of negative pressure near the openings;

d) cross ventilation is easily achieved when wind is perpendicular to the building.

Permeability to natural ventilation can be singled out as the main form‐finding principle for the design of the research station, because it is the most important strategy to achieve environmental comfort by means of comfort ventilation, as discussed in Chapter 2. For this reason, ‘organic’ and ‘aerodynamic’ shapes have been favoured instead of orthogonality. The radial configuration of the research station has been adopted not only for the purpose of permitting easy expansion, but because it is the most favourable in terms of allowing cross ventilation. Each wing can be expected to act as a kind of ‘wing wall’ that creates pressure differences between each side in relation to incoming winds, promoting air movement across the building (Givoni, 1998). The radial configuration also keeps floor plans relatively shallow, also facilitating cross ventilation. However, as more research wings are added in larger stations, there is an increased chance that the ‘core’ part of the station might become overly obstructed by the own shape of the building. For this reason, strategies have been developed in order to increase the general permeability to incoming winds and to attract ventilation to the central part of the station. This is basically achieved in the following manner: First, the roof of each of the research wings contains wide, lightly curved horizontal openings that function as ‘wind scoops’, capturing incoming wind. Second, a wind cowl located on the top part of the central roof promotes air exhaust by buoyancy. The roof openings located downwind function in turn as additional exhausts.

AA E+E Environment & Energy Studies Programme Architectural Association School of Architecture

Wind cowl The ‘wind cowl’ is a light rotating device located on the top part of the roof that can dynamically respond to the wind by sliding on a circular bed made of some low‐friction material such as graphite. It is closed on one side and open on the other, and a large vertical foil will make it rotate in reaction to wind in order to always keep the open part oriented downwind (Fig. 3.43). The wind circumvents the wind cowl, creating positive pressure on one side and negative pressure on the other. This area of negative pressure will create an exhaust effect that attracts air movement from inside the building. A CFD simulation can demonstrate how the air is accelerated around the wind cowl and slowed down in the area of its ‘wind shadow’, which in turn will accelerate air coming from inside the building through the exhaust (Fig. 3.44) Fig. 3.43. Principles behind the functioning of the wind cowl.

Fig. 3.44. Effect of the wind cowl on the surrounding wind speeds. 66

The Amazon Research Network Chapter 3

Computer fluid dynamics simulation (CFD) CFD simulations have been made in order to assess if the proposed solutions for natural ventilation are functional, and to estimate the rate of air movement that occupiers might enjoy inside the station’s facilities. The main purpose of these simulations is to verify if air movement happens as predicted, especially in the case of the roof wind scoops and the central wind cowl. The software utilised for these simulations was WinAir, a plugin for Ecotect, which was developed by the Welsh School of Architecture of the Cardiff University. This is not a ‘high‐end’ software in comparison to other, more accurate CFD simulators such as Ansys CFX and Ansys Fluent, and there are limits to its resolution in terms of interpreting the finer details of the architectural space. However, they do achieve enough accuracy to demonstrate that incoming wind will indeed be drawn in by the wind scoops, that the central wind cowl functions consistently (Fig. 3.45), and that the roof apertures will also serve as exhausts on the downwind side (Fig. 3.46). Images on the following pages demonstrate the expected dynamics of air movement in and around the ground floor of the building considering two different wind directions, parallel (Fig. 3.47) and perpendicular (Fig. 3.48) to the main body of the station.

Fig. 3.45. Dynamics of air movement when roof openings are facing incoming winds.

Fig. 3.46. Dynamics of air movement when roof openings are oriented downwind of incoming winds. 67

AA E+E Environment & Energy Studies Programme Architectural Association School of Architecture

3.3.6 Solar control Fig. 3.49. Preferred orientation of a ‘Level 3’ station in relation to solar geometry.

Fig. 3.50. Effective solar protection is achieved by the roof overhangs on either side of the research wing, offering complete protection for solar angles higher than 45o.

Solar control is an important parameter for passive design and deserves particular attention. As the research stations are expected to be built in several different locations, their orientation has to be considered on a case‐by‐case basis. However, some general guidelines can be established, such as favouring east‐ west configurations because they cause less exposure to unwelcome sun at lower angles in the early morning and late afternoon (Fig. 3.49). As the combined solution of utilizing a piaçava layer beneath the PV roof cladding in conjunction with ventilated attics offers enough protection from incident solar gains over the roof, a ‘spread‐out’ roof becomes an interesting option. Large roof overhangs all around the building will not only offer effective protection for the façades (Fig. 3.50), but will also create verandas that constitute transitional spaces between inside and outside. Figure 3.51 demonstrates how the surrounding verandas act to create a gradual transition between areas completely protected from the sun and the outside.

AA E+E Environment & Energy Studies Programme Architectural Association School of Architecture

4. Conclusion The Amazon Research Network is a hypothetical idea that would probably need to walk a long and hard road in order to materialize. It is an ambitious proposal that would certainly face several difficulties in the process of becoming a feasible project, including economic and technical constraints that would probably change several aspects of the original design. In this process, it would possibly meet a lot of resistance from skeptics who do not believe that the Amazon is realistically under threat and thus do not think it worth the investment. It would also be resisted by fatalists who do not believe that a new mode of relating to the natural environment is possible, and therefore do not see the possible contributions that might be made by such a project. However, the greatest resistance would come from those who actually profit with the systemic destruction of the forest for capital gain and wish to deprive the world of its immense richness and beauty. This project is essentially an attempt to demonstrate that other outcomes for the Amazon Forest are possible if action is taken with proper knowledge and guided by correct principles. In this sense, the Amazon Research Network is an intentionally bold proposal that is meant to inspire people, and as such must rely on some base assumptions about its own feasibility, or else there would not be enough leverage to get the design process started.

Architectural Association / Graduate School MSc Sustainable Environmental Design

MSc SED dissertation projects

social housing in Costa Rica strategies and consideration for passive design

September 2008 Michael Smith Masis

[Chapter 1] Costa Ricaâ&#x20AC;&#x2122;s Social Housing Scenario Background

In developing countries, the phenomenon implications upon the urban thread. Just in where 67% of the inhabitants are poor. In 3 spontaneous sprawls without a clear develop improvement and shelter.

In the past 10 years Costa Rica has experie fact the Great Metropolitan Area where 56% outside the Great Metropolitan Area are movi taking place. It is expected that this trend wi tourism and services. As a consequence, jeopardizes low-income familiesâ&#x20AC;&#x2122; aspirations In developing countries, the phenomenon of migration into the cities carries profound socioeconomic implications upon the urban thread. Just in Central America of the population lives in urban areas, population still 62% lives intotal poverty. where 67% of the inhabitants are poor. In 30 years urban populations has increased 48% over disorganized spontaneous sprawls without a clear development strategy. Where the poorest are seeking for a socioeconomic improvement and shelter.

In the past 10 years Costa Rica has experienced such impacts of migration and labor mobilization, and it is in fact the Great Metropolitan Area where 56% of the population lives. However recently rapid urban developments outside the Great Metropolitan Area are moving towards rural areas, where the principal tourism investments are taking place. It is expected that this trend will continue in a country that its national economy depends 60% on tourism and services. As a consequence, housing demand has augmented dramatically, but affordability jeopardizes low-income familiesâ&#x20AC;&#x2122; aspirations for good low-cost quality housing; in a country where 22% of the population still lives in poverty.

The typological guidelines per region are probably the most significant of the requirements, nevertheles qualitative and environmental issues still quite weak into a certain extent. Despite this fact, this set of guideline at least points out the necessity of climatic differentiations for particular regions. These are some of the basi criteria for each typology (figure 5):

n of migration into the cities carries profound socioeconomic Central America 62% of the total population lives in urban areas, 30 years urban populations has increased 48% over disorganized pment strategy. Where the poorest are seeking for a socioeconomic

enced such impacts of migration and labor mobilization, and it is in of the population lives. However recently rapid urban developments ing towards rural areas, where the principal tourism investments are ill continue in a country that its national economy depends 60% on housing demand has augmented dramatically, but affordability for good low-cost quality housing; in a country where 22% of the

Typologies for Region 1: For warm humid conditions mainly in Caribbean and south pacific regions Houses should be provided over stilts to prevent floods threats or humidity problems. The floors must b treated against humidity problems, moisture and mould.

Typologies for Region 2: For the hottest regions in the country, mainly north and central pacific locations They required being fresh and well ventilated. Cross ventilation is required with openings over th windows and doors, thus the openings have to be covered with fly screens for allowing constan ventilation. Minimum floor to ceiling heights should be 2.6, but 2.45 meters can be used with opening (fix glazing and ventilation openings) ratios of 50% of the total house envelope or a minimum of 20% t the floor ratio. Also the lateral openings for the glaze areas should have additional protection agains direct solar radiation and extra overhangs have to be incorporated.

Typologies for Region 3: All projects that are allocated on aborigine settlements or conservation area located under slightly warm-humid conditions. The main objective is to maintain cultural traditions materials, and plan distributions. These typologies are required to be fresh during day and warm a night.

Typologies for Region 4: All urban zones in the great metropolitan area, and for instance genera building codes apply. Social Housing in Costa Rica’s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008

[Chapter 3] Building Analysis The Social Housing typology Social housing projects have to meet always cost effective requirements to shelter essential living conditions. In Costa Rica, it is a main concern to obtain the â&#x20AC;&#x2DC;maximum resultâ&#x20AC;&#x2122; out of the minimum square footage of construction for a single detached housing unit. Due the lack of resources these typologies are constantly facing the challenge of optimization of spaces and resources for low-density units. This becomes quite evident in developing countries, where low-income families have to struggle with such critical constraints at all time. According to the above, it is fundamental to understand space usage in order to evaluate and determine the necessary amount of space required for the various activities in a dwelling. Mapping spaces, functions and activities, becomes relevant to visualize: How? Where? , and when?, main activities are taking place. Coupling this information within the climate denotes quantity and quality regarding intrinsic architectural responses for spatial layout, form and materiality.

Space Classification The spaces within this type of dwellings could be classified according their sensitivity (private, semiprivate & communal) and whether the functions might be performed inside or outside. Figure 15 shows that over a 42 square meters single detached unit (minimum by local regulations) 66% of activities could be performed under a semiprivate or a communal space, i.e. under a covered space or even outside. In other words, 39% of the areas are constricted for a specific private use (i.e. bedrooms), whilst the rest of the spaces (61%) might be used under different levels of sensitivity and respond to users when indoor-outdoors activities are required. Here it becomes quite evident that even though most activities must be sheltered due climatic constrains, there is an opportunity to extend activities outdoors gradually. At the same time, semiprivate spaces have an interface role among other functional areas, by allowing indoors to outdoors transition and promoting different levels of sensitivity and location.

Social Housing in Costa Ricaâ&#x20AC;&#x2122;s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008

Occupation patterns

In Costa Ricaâ&#x20AC;&#x2122;s warm humid climates most of the activities occur during daytime, therefore the importance to match diurnal occupational patterns within temperatures and solar radiation. Figure 16 shows on top, climate data of May (yearly critical hot period) with daily average outdoor temperatures (DBT) and global radiation. Underneath the climatic data, main activities are plotted over a 24 hours nonlinear graph for a single detached family dwelling (4 persons) on a typical weekday, and considering when occupants arrive or depart (to-from school or work). Below the nonlinear graph a mapping of the occupational patterns allows tracing 5 main functions along time, space and density according to its sensitivity.

It can be seen that from 11-14 hrs (16% day), the DBT outdoors are above the adaptive comfort limit (Tn+2.5K), but still below the extended comfort limit by increasing wind speed up to 1.0 m/s for a ventilative passive cooling

Heat gains

May average peak temperatures do not rise above the extended comfort limits, however by adding internal hea gains such as occupancy, appliances and solar radiation conducted into the space through the roof, the interna conditions of a dwelling could get problematic; especially by assuming wrong design decisions on the overa design scheme of the house. Figure 17 denotes that the sum of all accounted internal heat gains (1700w estimated a temperature rise of 5.1 K from 11 to 14 hours, by which indoors temperatures rising above 32 degrees.

The schematic analysis showed that a strategic zoning of appliances for heat dissipation would benefit some areas such as the kitchen. Here appliances could be located over leeward and perimeter facades in order to respond to a ventilation strategy (convection), thus get rid of the heat inputs generated by cooking appliance during peak hours (e.g. lunch). Additionally it was also observed that the building envelope represent more than 50% of the overall internal heat gains indoors. Furthermore it is critical to emphasize that in Costa Rica the roo is one of the most important elements in a building envelope to control heat generated by solar radiation -It i locally agreed that shading under these latitudes is a major concern in bioclimatic design.

Social Housing in Costa Ricaâ&#x20AC;&#x2122;s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008

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Spatial opportunities Regular social housing practice in Costa Rica tend to concentrate all dwelling functions indoors. Despite this Spatial opportunities fact, the potential for semiprivate or communal activities as pointed previously demonstrates a real Regular with social housing practice Costa Rica tend to concentrate all dwelling functions indoors. Despite indoor this relationship the outdoors. Thisinrelationship becomes fundamental when more space or coupling to fact, the potential for semiprivate or communal activities as pointed previously demonstrates a real outdoor temperatures is needed, and when any ventilation strategy is necessary to achieve thermal comfort, relationship the outdoors.performance This relationship fundamental when more space or coupling indoor to thus an optimumwith environmental mustbecomes be achieved. outdoor temperatures is needed, and when any ventilation strategy is necessary to achieve thermal comfort, thus an optimum environmental performance must be achieved.

Figure 18 exemplifies conceptually how the degrees of enclosure may perform over a daily base analysis, wherever could be defined by degrees the degree of enclosure occupational patterns. The different Figurethe 18architecture exemplifies conceptually how the of enclosure may and perform over a daily base analysis, levelswherever of enclosure expand and contract to respond to function, space and climate adaptation demands. It the architecture could be defined by the degree of enclosure and occupational patterns. The different questions internal and external appear or disappear needs. demands. It levelshow of enclosure expand and divisions contract to respond to function,within spacethe andoccupants climate adaptation questions how internal and external divisions appear or disappear within the occupants needs.

From left to right at the table bottom (figure 18), the scheme evolves from a lower to a higher degree of activities. From to right are at theclearly table bottom (figure scheme evolves from requires a lower to less a higher degree activities. Where twoleftspaces defined; one18), is the private, for activities space andofthen it looses Where two spaces are clearly defined; one is private, for activities requires less space and then it compactness gradually by becoming ‘openable’ towards semiprivate and communal activities. looses In addition, compactness gradually for by this becoming towards semiprivate and communal activities. In addition, spaces under contraction type of‘openable’ climate represent ‘less warm environments’ and the opposite for spaces under contraction for this type of climate represent ‘less warm environments’ and the opposite for openness and envelope permeability. When spaces unfold and open, they will tend to be more capable to openness and envelope permeability. When spaces unfold and open, they will tend to be more capable to allowallow ventilation; thus coupling within outdoor conditions, for several activities such as domestic shores, work or ventilation; thus coupling within outdoor conditions, for several activities such as domestic shores, work or even even producing -all -all under comfortable producing under comfortableconditions. conditions. Finally, identifying newnew programmatic fundamentalwherever wherever live, work or progressive growth of Finally, identifying programmaticopportunities opportunities is fundamental live, work or progressive growth of the dwelling questions new housingparadigms. paradigms. Social Social housing in in developing countries are constantly the dwelling questions new housing housingtypologies typologies developing countries are constantly to the families’necessities. necessities. For For example housing scheme, where duringduring evolving according evolving according to the families’ example inina aproductive productive housing scheme, where daytime hours bedrooms could contract as furniture elements (e.g. shelve) and internal divisions could could daytime hours bedrooms could contract as furniture elements (e.g. shelve) and internal divisions disappear to perform productive activities within the household (figure 19). disappear to perform productive activities within the household (figure 19). Social Housing in Costa Rica’s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008 Social Housing in Costa Rica’s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008

As seen in Figure 26, by adding a vertical projected element of the size of the opening width with oblique winds, it is possible to double the average wind speed indoors. Then by increasing the projection as twice of the opening width, there is no significant increment from the one before, in fact there is a reduction over the maximum wind speed. For cross ventilation, perpendicular air flows have a short circuited air flow pattern with poor secondary flows inside, while oblique wind directions enhances air circulation & distribution.

For warm humid climates, the recommended size of the openings is of 40 to 80% of the wall area. This might become quite useful but it demands the interaction within other design variables such as dimensions shifts and orientation for its effectiveness (Figure 27). “Because the external walls of detached single family houses face at least four directions, these houses are less sensitive to orientation effect, although the problem of choosing the orientation of the different rooms, and specially the orientation of the large windows still exits ” (Givoni, 1998) The quote above demonstrates how the effect of increasing size of the window as a function of orientation is critical. In fact it is a definitive issue to achieve an appropriate ventilation strategy. This becomes quite evident with cross ventilation and oblique winds where airflow and air speed increases the most. However, perpendicular winds might also experience the same effects. On the other hand, single sided ventilation has a small consequence within perpendicular winds, and wind pressure or speed may increase only with oblique winds.

At the same time, the variation of sizes among the openings produces different wind-driven patterns in cross ventilation. For example having the inlet and outlet of the same size produces the highest airflow rates indoors. By reducing the inlet size, wind acceleration is experienced with a maximum air speed and narrower air stream. It is said that this type of arrangement may be suitable to locate a particular place of a room such as a bedroom. A recommended ratio of 1/25 inlet-outlet may perform this task (Stagno & Ugarte, 1998). Conversely, decreasing the outlet area equalizes the air speed distribution but reduces wind speed with a uniform air stream, which in way could be suitable for living rooms where ventilation is required at any point of the room. Social Housing in Costa Rica’s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008

Among the different options of varying orientation and size, the greatest average of external wind speed indoors is achieved by cross-ventilation with the largest openings and oblique winds of 45º (Figure 28). Whilst average wind speeds reachesoptions 65% ofofthe external air velocity, with perpendicular winds itofreduces 47%. In the case of Among the different varying orientation and size, the greatest average externaltowind speed indoors small inlet with largest outlet it gets hold of 44% of the external air velocity, but with greater maximum wind is achieved by cross-ventilation with the largest openings and oblique winds of 45º (Figure 28). Whilst average speed (152%). In the case of adjacent openings, perpendicular winds achieves greater average wind speed wind speeds reaches 65% of the external air velocity, with perpendicular winds it reduces to 47%. In the case of indoors of 51%, an inlet andhold outlet of 1/3ofofthe theexternal wall size. small inlet with with largest outletofit2/3 gets of 44% air velocity, but with greater maximum wind speed (152%). In the case of adjacent openings, perpendicular winds achieves greater average wind speed indoors of 51%, with an inlet of 2/3 and outlet of 1/3 of the wall size.

Inlets position determines the main airflow stream indoors, and it is the vertical location, which determines main airflow level towards the living zone, hence the occupants cooling. According to several authors, the role of the Inlets position determines the main airflow stream indoors, and it is the vertical location, which determines main outlets is of secondary importance. Figure 29 illustrates how different vertical configuration of the inlets defines airflow level towards the living zone, hence the occupants cooling. According to several authors, the role of the airflow patterns within the space. Inlets at the body height are the most advantageous for cross ventilation and outlets is of secondary importance. Figure 29 illustrates how different vertical configuration of the inlets defines cooling at the living zones. High inlets are less suitable for occupants cooling, but useful for a night ventilation airflow patterns within the space. Inlets at the body height are the most advantageous for cross ventilation and strategy; high lowzones. inlets High reduces airare circulation on the zones.cooling, Also it but is important that there cooling at theand living inlets less suitable forliving occupants useful fortoa consider night ventilation isstrategy; always sharp airspeed drop below the window sill unless a proper design solution is provided. high and low inlets reduces air circulation on the living zones. Also it is important to consider that there is always sharp airspeed drop below the window sill unless a proper design solution is provided. Roof openings may be used to encourage an adiabatic flow, which enhances a natural stack effect when vertical opposite openings are place. Roof openings may bedifficult used totoencourage an adiabatic flow, which enhances a natural stack effect when vertical opposite openings are difficult to place.

For ventilation determining the inlets opening type is a fundamental due its decisive role, which determine airflow For ventilation determining the inlets opening type is a fundamental due its decisive role, which determine airflow patterns indoors. In other words, the ‘window’ type selected will enhance or reduce dramatically the patterns indoors. In other words, the ‘window’ type selected will enhance or reduce dramatically the effectiveness for any given ventilation strategy. Among basic openings types, the most suitable designs for warm effectiveness for any given ventilation strategy. Among basic openings types, the most suitable designs for warm humid conditions are the ones that allow ample air passing and enhances velocity distribution. Here top hung or humid conditions are the ones that allow ample air passing and enhances velocity distribution. Here top hung or Venetian for this this asset. asset. Venetianblinds blindsare arethe the most most suitable suitable for

Comparative analysis To underline basic ventilation criteria, the “f” house is compared with a recent build social housing unit, which slightly intends to emulate its typology. The other social housing project is located at Nazareth de Siquirres, a community on Costa Rica’s Caribbean region. This project was constructed under government’s new typological regulations for hot humid climates. This house is half a meter above ground and comprises 3 bedrooms, kitchen, and bathroom (Figure 34).

For the comparative analysis the “f” house is taken as case study ‘a’ and Nazareth’s community dwelling as case ‘b’. The comparison follows; ventilation configurations-useful depths, where useful depths are measured to verify distances, spatial dimensions and floor plan areas. A Floor to opening ratio aims to define coefficients for apertures areas on each unit, while wall to openings ratios are extracted as well. Then airflow pattern analysis over the plan layout, attempts to illustrate wind driven patterns with pressure and suction flows. At last an occupation-air exchange rate is given for living room, which volume may comprise the highest occupancy rate of 4 persons; consequently the relationship between the air exchanges requirements and aperture coefficients via the envelope should be revised.

Figure 35 illustrates that both approaches have a convenient narrow depth, which facilitates cross-flow over a maximum useful depth as twice the floor to ceiling height; in this way 6 to 7 meters is the maximum distance between openings for 3 meters height.

Social Housing in Costa Rica’s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008

façade, while it is 24% on its opposite leeward façade. At this point the pressure effects accelerates air velocity indoors; hence a cooling effect may happen with efficient cross ventilation. Case ‘b’ denotes a totally distinct situation, in which a poorly shaded long axis leeward façade does not even have ventilation apertures and its single sided windward apertures has only 6% of the façade area; no cross ventilation is expected for these rooms.

On Figure 37, an optimum orientation is assumed where most rooms are facing to the prevailing breeze and the linkage between leeward and windward side to utilize pressure differences. On case ‘a’ the long windward façade catches the breeze. Then cross ventilation happens when wind driven flows penetrate through internal wall vents and reduced internal obstructions. On the other hand case ‘b’ just allows single sided natural ventilation for the rooms and cross ventilation is only expected in the living room. Negative flows and turbulence may prevail inside rooms as a result of the internal walls obstructions. Social Housing in Costa Rica’s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008

On the other hand, the opening to floor ratio (Figure 36) for case ‘a’ is 50% and case ‘b’ only 9%. Here ratios for

This veranda house concept is derived from the shade veranda. Australian architect Glenn Murcutt developed a first approach upon this concept. Based on climate parameters for Southern Australia, used a long plan to provide cross ventilation in summer. A shallow veranda buffered the interior space and adjustable louvers are used to control the sun and ventilation. The veranda allows closer connection between interior spaces and connects inside to outside spaces. At the same time enhances breeze access and to shield from the sun with less structural elements, which makes it cost effective by not requiring extensive amounts of materials, with minimum architectural elements and becomes a successful buffer space along side of the house. These design principles of his work can be appreciated on the Simpson-Lee House (Figure 39).

Australian architect Gabriel Poole also explored the concept of using the veranda house strategy. He developed an experimental tent house prototype (Figure 40) within a linear plan as on Murcutt’s buildings to provide summer cooling. The innovative approach was to manipulate the line of enclosure, whereby walls could be removed, giving the potential for the rooms to become an external veranda-like space. Here the ‘Space is implied rather than defined due the lack of walls’ (Hyde, 2000), with a strategy to articulate the long shallow veranda contained by the rooms and generate free standing pavilions, where the fold-up of the walls provide a higher degree of flexibility in the rooms. The climate responsive concept depends on the position of the ‘wall’; for example when it opens, a veranda is provided to create shade and openness to the room, or when the wall is closed, an interior space is generated within its enclosure. This particular concept of houses emphasizes that the veranda derives its character and climate response from the degree of enclosure provided by the building. It is the manipulation of its degree of enclosure and integration within the buildings functions that new forms of veranda can be developed. The value is to ensure a variety of functions and provisions of thermal delight for the occupants.

Social Housing in Costa Rica’s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008

er along axis and is covered by an un-insulated, roof with broad eaves. The users d fresh air can be brought via movable panels in the walls or by ventilation vents on the cabinets the facades open, yet closed bywith wire broad screening, so that rder along axis andalong is covered by anis un-insulated, roof eaves. Theall users pened to various degrees. The facades provide a wide range of possibilities to be fresh air can be brought via movable panels in the walls or by ventilation vents on y the occupants, which makes this example a straightforward image for its ventilation

er the cabinets along the facades is open, yet closed by wire screening, so that all ened to various degrees. The facades provide a wide range of possibilities to be he occupants, which makes this example a straightforward image for its ventilation

sa Kike, is an example of local contemporary architecture that manages to provide lope that responds to the climate. This 2008 Riba award-winning project designed s, is located in a Costa Rican warm-humid region, and relies on a close relationship ts own envelope the manner by which this relation gets well articulated.

After knowing the total required resistance, individual values are assessed for each layer of the roofing system. It is possible to observe in Figure 47, that the major contribution from the resistances values comes from the air cavity and insulation material, however the latter unfortunately is still rather expensive to achieve for most low After knowing the totalsame required individual values are assessed for eachwith layer of theroofing roofingsystems, system. It cost housing. At the timeresistance, by comparing the obtained U-value with others similar it is possible to observe 47, that the major contribution from values from the could be observed that in forFigure any surface temperature rise above the 30 the ºK, resistances U-values could varycomes on a range fromair 1 cavity and insulation material, however latter unfortunately is still rather to 1.5 W/m2ºC, with approximate ceiling the temperature excess of 2.5 to 3.5 ºK. expensive to achieve for most low cost housing. At the same time by comparing the obtained U-value with others with similar roofing systems, it could be observed that for any surface temperature rise above the 30 ºK, U-values could vary on a range from 1 to 1.5 W/m2ºC, with approximate ceiling temperature excess of 2.5 to 3.5 ºK.

Parametric test

Despite the fact of the software sensibility and materials calibration, the resulting computational values were approximates which help to illustrate what was approached with the ‘manual calculations’. Even though there are some minor discrepancies between expected simulations results and manual calculations, the performance contribution of each layer of the roof construction can be visualized in a practical way. Form Considerations For shaping the roof under this type of climate, it is a primarily concern the surface tilt (slope degree), its orientation and extension of the eaves for solar radiation protection. According to this in Costa Rica’s social housing projects roofs are typically provided as double-pitched slopes (15% to 20% gradient) and with 0.50 m overhangs; conversely due economical factors disregarding of orientation and ‘sloping criteria’. It is a main concern at this level of research to analyze main form considerations, which can help to define criteria for the roof form. Surface Tilt As the sun’s path for this latitude is near the zenith, very strong irradiation affects the envelope, especially for surfaces, which are perpendicular to the sun. Figure 49 illustrates that the angle of solar incidences could be reduced during critical hours of solar radiation impinge, by tilting the horizontal surface (roof) with higher slope degrees to reduce ‘perpendicularity’ towards the sun. Even though the south façade accounts yearly higher levels of global radiation, the north façade can become especially critical in a month like May; when the sun is on the north side, that is why certain northern tilt angles were having higher levels of solar radiation due is proximity to perpendicular incidence. This can become quite problematic in month that has high temperatures and solar radiation peaks. In terms of potential roofing slopes, angles between 15º and 30º are more likely to be found in typical roofing scheme in Costa Rica. In fact as seen on vernacular examples, it is commonly to find slopes of 35% gradient (22.5º), with multiple pitches to reduce the perpendicular impinge of solar radiation. Important improvements can be seen at this point when predominant sloping facades can be located at north and south; hence containing most of the roof surface over the long axis, when parallel to the sun path. From the above it can be said that solar radiation approaching an exposed surface could be reduce as function of the tilted plane. For example by tilting the surface with a 30 degrees gradient the north slope have experience a reduction of 15% of the average incident global radiation, whilst the south have 5% less radiation with the same angle. Additionally higher angles or close to vertical surfaces received less solar radiation, which can be strategically accounted for narrower shaded east-west facades.

Social Housing in Costa Rica’s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SMITH.M / 2008

Space organization ¥

The dwelling has to facilitate a wide range of spatial options for a very compact internal layout. Figure 55 shows how from enclose specific use to a wide-open multifunctional space, the plan responds to users demands for living, working, growing or producing in the same place. Here private spaces such as single banked bedrooms can be grouped along the north side where less overhang extensions are required. The area of these rooms can be reduced gradually through its internal partitions, thus semiprivate and communal activities can take over a greater area. The expansion takes into account balconies or verandas to enhance a closer relation with the environment, whilst it incorporates to the open ‘interior’ communal plan as well.

Air movement ¥

The dwelling has to ensure maximum cross ventilation for the open communal area and single banked rooms. Here winds approaching with incidence angles of 45 degrees have a greater potential to increase speed indoors, hence openings should be oriented accordingly or at least incorporate wing walls to capture the eastern prevailing breezes.

Main openings are expected to be link with semi outdoors spaces, e.g. the south elevation due shading reasons can contain a veranda within a deeper overhang. Here a large south facade with external ‘adjustable wing walls’ located at the veranda external ridge can re-direct winds with beneficial angles for

comfortable conditions with adequate shading and ventilation. In fact depending o and available resources both systems can coexist under the same scheme.

uld allow along the short axis (south-north) air cross flows. At this juncture the s the overall performance of internal cross flows, hence a degree of air egrated to the partitions. Perpendicular-to-wind interior walls have to be able to his asset. Figure 56.C illustrates how this action can be promoted with different shutters, movable panels or even totally folding-up the partitions. Additionally equired to be reduced, parallel-to-wind divisions should be compacted, without main air stream along the shorter axis.

ventilation in order to couple with outdoors conditions, hence to allow more nal-external obstructions to prevailing breezes.

iances can be set along leeward openings within the open communal space in any heat input through the immediate opening (Figure 56.D).

mposite structural elements is relevant for cultural, economical and structural n’s climate, heavy and lightweight structures can achieve similar thermal th adequate shading and ventilation. In fact depending on the user necessities oth systems can coexist under the same scheme. ¥

A composite construction system might be beneficial to reduce cost and to environmental design strategy. For example a heavyweight construction can be u structure in a dwelling, whilst lightweight elements can be attached (roof, wa elements within the building envelope. Here the main structure also defines s natural threats such as: floods, hurricanes, and earthquakes (Figure 57.A).

The main structure geometry should determine how internal partitions can mo spatial approaches discussed previously for organization, e.g. retractile panels ca wind the main frame (Figure 57.B), or to expand to the communal areas.

The openings ¥

Multiple openings on the walls should be encouraged to make available a wide ran natural ventilation.

Social Housing in Costa Rica’s Warm Humid Climate / MSc. Sustainable and Environmental Design / AA Grad School / M.SM

A typical roof can be provided as single, double or quadruple pitches, however a double pitch roof oriented north to south will benefit from less solar irradiation exposure. Additionally the pitch angles can vary on a range of 15º to 30º, as however considering higher tilt angles can reduce the effects of radiation impinge (Figure 59.A).

In general terms overhangs can provide shading during critical hours for most of the year for north and south walls, with the exception of late afternoon or early morning periods (from about 3-2 hrs). In case of requiring any additional shading for lower altitude irradiation, this can be prevented with vertical elements such as wing walls, which can act as multi purpose devices for shading and ventilation. The specific shading recommendations for both VSA and HSA are summarized on Figure 59.B.

Figure 59.C illustrates several roof variations that can be put into consideration. But this will greatly depends on specific locations and occupant’s economic possibilities. The roof design should attain to basic standards and less use of materials, within an adequate balance of reducing the area of exposure

Architectural Association / Graduate School MSc Sustainable Environmental Design

MSc SED dissertation projects

lessons from the Masters a stydy of Tertiary Educational Buildings in India

September 2013 Megha Nanaiah

Architectural Association / Graduate School MSc Sustainable Environmental Design

MSc SED dissertation projects climatic adaptation of the office building typology in the Mediterranean climate

September 2013 Jonathan Natanian

2.1 THE FUTURE OFFICE SPACE New trends and design consequences “Work is no longer a place you go. It is something you do” (Dixon & Ross 2011)

2.1.1

THE NEW WORKPLACE

NEW GENERATION

Analysts believe that society is in the middle of a major revolution led by Generation- Y,

defined as those who were born between 1980 and 2000 (Johnson et at. 2011). Gen-Y is generally marked by an increased familiarity with instant communication, social media and other Web technologies (Figures 2.1.1-2). Nowadays, in contrast to the specific prescribed tasks of the traditional “office factory” which had been executed through single fixed workstations (Figure 2.1.3-4), the economic shift towards the knowledge society has created a new need for variety of alternative spaces in which the knowledge workers will have higher levels of interaction and autonomy (Harrison et al. 2004).

Figures 2.1.1-2 (2 upper images) the new Generation-Y (Source left: NYU Wagner)

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Figure 2.1.3-4 (2 lower images) Trends in Office layouts from the fixed prescribed tasking (left) to productive thinking space (right). (Sources: left- DeadInk.com, right – Google ) →

SPACE REQUIREMENTS & ACTIVITIES

New office concepts reflect a move towards more flexible office spaces

and work locations. New technologies which enable people to work virtually anywhere, resulted in new work patterns such as the “nomadic workers” characterized by portable computers and multiple workstations. However, the social importance of the workplace is likely to continue to serve as a vital element and the new offices will be regarded more as meeting centers or hubs for social interaction and exchange of ideas rather than fixed places for private work (Figure 2.1.5).

“Innovation springs out of the ‘adjacent possible’ - the most inventive places are hives of activity where people get together and share ideas” (Johnson 2011) Figure 2.1.5 Social interaction will keep serving as a vital element in the new office space (Source: Davis Meyer) ↑

THEORETICAL FRAMEWORK I THE FUTURE OFFICE SPACE

TECHNOLOGY

More than in any other typology, technology had changed the way we work substantially

(Figure 2.1.9); As part of their study on trends in office internal gains, Johnson, Counsell and Strachan (2011) suggest four key interrelated trends which could be used to categorize the new technological interaction between Generation- Y users within the office space: cloud computing, mobile computing, surface computing and sensor networks; they discuss the contradiction between two trends – one represents the improvements in efficiency of appliances, and the other, our increasing dependency on technology to achieve more productivity; they suggest that these trends will result in two different energy scenarios for the future – an energy conscious and technology explosion scenarios; Figure 2.1.10 shows the simulation for each of these scenarios along a typical day and for an annual consumption; these charts clearly express how big the potential of these trend is to offset levels of energy consumption and comfort within office buildings the near future.

Figure 2.1.9 Technological evolution of workspace platforms (Sources left to right: richardmmarshall.com, stefandidak.com, gizmag.com) ↑

Figure 2.1.10

Equipment usage daily profile

(left) and annual energy demand (right) for 3 scenarios (Source: Johnson et al. 2011) ↑→

ADAPTABILITY

Recent studies (Capper et al. 2008) further reinforce the direct correlation between the

control the occupant has on his immediate office space and his comfort and productivity levels; These indicate that future consideration should be given to the right balance between allowing manual control for the occupants versus automated systems in order to optimize efficiency levels (Figure 2.1.11 left & middle). The design of control interfaces becomes critical and should be considered against the levels of engagement and expectations of the occupants to reach optimum performance; thus in the future office, more complicated systems are not necessary optimal and passive strategies are not necessary irrelevant. The adaptability levels of occupants to perform their work in different conditions (such as outdoor and semi outdoor spaces) should be considered as a starting point for addressing the need for diverse working environments within an office buildings. (Figure 2.1.11 right)

Figure 2.1.11 (left to right) 1. Manual air inlet control, Solar XXI Lisbon, Portugal 2. Electrochromic Glazing control Via IPAD (Source : ABM.com) ↖

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3.1 CLIMATE ANALYSIS 3.1.1

ISRAEL’S COASTAL PLAIN CLIMATIC CHARACTERISTICS

LOCATION (31.2N 34.7E) Israel is located in the eastern boundary of the Mediterranean, stretched linearly 424 km north to south along the Mediterranean coast with relatively shallow width ranging from 115km to only 15km (figures 3.1.1-2).

31.2°

34.7°

ACTERISTICS

iterranean, stretched linearly 424 km north to south along

h ranging from 115km tolocation only Figure 3.1.1 Israel’s global geographic ↑ 15km (figures 3.1.1-2).

Figure 3.1.2 Israel’s climatic zoning map (Sources: photos (top to bottom) - Eli Zahavi, Getin travel.com, celsias.com, illustration – After Perlmuter et al. 2010 ) →

Beit Dagan weather station 32°N 34.8°E

CLIMATIC REGIONS Despite its small size, Israel has a variety of landscapes, changing dramatically between highlands, deep valleys,

31.2°

coastline and deserts which experience different climatic conditions yearly. Although the traditional climatic division in Israel since the 80’s had been between four different climatic zones, new research funded by the state (Forshpan et al. 2000) suggests a new division to three main climatic regions (figure 3.1.2): Zone A-B. The coastal plain - includes the western coastline and northern areas, characterized by hot and

relatively humid coastal Mediterranean climate. This research focuses on this climatic region which accounts for the largest conglomeration of office buildings in the country around the Tel Aviv metropolitan area. Zone C. The highland area – Includes Jerusalem and the eastern mountain strip, characterized by drier and

colder temperatures with lower cooling demand and higher heating demand. Zone D. The desert area – including the Negev desert with hot dry arid climatic conditions.

TEMPERATURES Figure 3.1.3 (opposite) shows the monthly diurnal external temperature averages recorded by Beit Dagan weather station (See location in figure 3.1.2); the chart shows relatively high external temperature across the year, with mild fluctuation annually between mean maximum temperatures reaching 320C during July and august, and mean minimum temperature dropping to 90C during January. The hot period extends from June to September inclusive; it is almost rainless, with average temperature of 270C and diurnal temperature range of 90C between day and night. The cold period (Dec-Feb) is mild and relatively sunny with mean maximum temperatures of 190C and an average of 140C. Mid-season months (March-May and Oct-November), are categorized by mild weather temperatures ranging between 280C mean max. and 110C mean min. Beit Dagan station

32°N 34.8°E 32

CONTEXT I CLIMATE ANALYSIS

BASE CASE B I single sided open office space (9m deep) B

Figure 3.2.15 Cooling loads annual breakdown vs. external and resultant temperature for Base case B (Source: TAS)

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Figure 3.2.16 Internal gains and cooling load annual breakdown

↑

for Base case B (Source: TAS)

In both open space configurations (Base cases B ↑ and C ↓), internal gains by occupants, lighting and appliances are increasing due to the rise of density compared to the Cellular office (Figure 3.2.16, 3.2.18); However, although solar gains per area are substantially reduced (Compared to the Cel. Office), these are still in the level of intensity to predominate the performance in both cases. The yearly breakdown of cooling loads as seen in Figures 3.2.15 and 3.2.17, could serve as an indication for the potential of a dynamic approach, which will create differentiation between periods of the year, towards a more advanced approach of comfort and performance.

BASE CASE C I DOUBLE SIDED OPEN OFFICE SPACE (15M DEEP)

Figure 3.2.17 Cooling loads annual breakdown vs. external and resultant temperature for Base case C (Source: TAS)

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Figure 3.2.18 Internal gains and cooling load annual breakdown for Base case C (Source: TAS)

↑

NORTH-SOUTH ORIENTATIONS

Figure 4.1.7 Double sided base case (C) facing NorthSouth on the annual Sun path (Source: Ecotect)

↑

NORTH

SOUTH

Figure 4.1.8 3d models and sun path diagrams for both North and South optimized external shading (Source: Ecotect)

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Figure 4.1.9 North (top) and South (bottom) references for optimized external

↑

shading (Sources: Norman Foster (up), Richards Rogers (bottom))

Figure 4.1.10 Daylight simulation for partly cloudy sky conditions without sun (June 21st 18:00, Sky Illumonance - 17,000 lux), (Source: Radiance)

↑

NORTH

SOUTH

Figure 4.1.11 Daylight simulation for partly cloudy sky conditions with sun (June 21st 12:00, Sky Illumonance - 20,500 lux)

Reflective internal blinds applied

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CLIMATIC ADAPTATION OF THE OFFICE BUILDING TYPOLOGY IN THE MEDITERRANEAN

EAST -WEST ORIENTATIONS

Figure 4.1.12 Double sided base case (C) facing EastWest on the annual Sun path (Source: Ecotect)

EAST

↑

WEST

Figure 4.1.13 3d models and sun path diagrams for both East and West optimized external shading (Source: Ecotect)

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Figure 4.1.14 East (top) and West (bottom) references for optimized external shading (Sources: Fabric architecture (top), Norman Foster (bottom))

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Figure 4.1.15 Daylight simulation for partly cloudy sky conditions without sun (June 21st 18:00, Sky Illumonance - 17,000 lux), (Source: Radiance)

↑

EAST

WEST

Figure 4.1.16 Daylight simulation for partly cloudy sky conditions with sun (June 21st 12:00, Sky Illumonance - 20,500 lux)

Reflective internal blinds applied

↑

CLIMATIC ADAPTATION OF THE OFFICE BUILDING TYPOLOGY IN THE MEDITERRANEAN

4.1.4

WINDOW TO WALL RATIO (WWR)

4.1.4.1 WWR AND DAYLIGHT This study explored the balance between minimizing exposure for thermal considerations while insuring adequate daylight levels for the 3 base case layouts through different orientations; the levels of exposure which were chosen were 45%, 60% and 75% (in Israel the spandrel opaque segment usually does not allow 100% glazing). The first step was to correlate between the daylight passive zone and the exposure levels; using the daylight design day to mark the target Daylight Factor, daylight simulations were conducted for the three exposures (for a single sided façade). Figures 4.1.20-21 show the summary of the passive zone and exposure (WWR) correlation; The graph shows how the reduction in exposure leads to shallower passive zone only in the 45% configuration while the reduction from 75% to 60% is neglectable.

Figure 4.1.20 Daylight Factor calculations as function of depth for 3 three different exposures (Source: Radiance) ↑ Daylight passive zone for 60%, 75% WWR ˃

Daylight passive zone for 45% WWR ˃

Figure 4.1.21 Daylight Factor calculations plotted on a typical section of a single sided open space showing two different passive zones for 45% WWR and 60 and 75% WWR (Source: Radiance)

↑

CLIMATIC ADAPTATION OF THE OFFICE BUILDING TYPOLOGY IN THE MEDITERRANEAN

In order to reaffirm the DF calculations further, the 45% WWR configuration was chosen for further daylight analysis (being the most restrictive in terms of daylight); the base case was simulated for three different envelopes – (a) unshaded, (b) with overhang and light shelf and (c) the same as (b) but with reflective louvers system for solar control. The daylight simulations were calculated for the design day sky conditions (17,000 lux sky Illuminance, with partly cloudy sky and no sun). The outcome (Figure 4.1.21) proves that by using a simple system which differentiates between the roles of the window as daylight distributer and solar protector, the passive zone could be extended with relatively small compromises in both daylight levels and views to outside. The principles of reflection could be further used to enhance daylight levels even further by using tilted ceiling, angular light shelves and reflective materiality.

Daylight passive zone for 45% WWR Basecase ˃

Daylight passive zone for 45% WWR w. external shading ˃

Daylight passive zone for 45% WWR w. external shading and ref. glare control ˃

Figure 4.1.21 Daylight Factor and illuminance calculations for 45% WWR base case with three envelopes, sky con. - illuminance 17,000 lux intermediate sky no sun (Source: Radiance)

OPTIMIZATION STUDIES I PRELIMINARY OPTIMIZATION

CONCEQUENCES OF AIR FLOW THROUGH THE OFFICE SPACE In order to estimate the ability of air flow to achieve a cooling effect throughout the office space, a specific day within a week in September was chosen, and CFD simulations where conducted for Base case C (Double sided open space); two configurations - standard height (2.8m) and exposed ceiling 3.4m high configuration were checked (the latter was considered in order to analyze how air flow pattern corresponds to the change in clear height). Figure 4.2.17 shows the thermal boundary conditions for the Ambiens CFD simulations which were obtained from TAS, coupled with climatic inputs form the Meteonorm weather file for Friday 7th of September at 12:00:

UGH THE OFFICE SPACE

OPTION A 4.2.17 Boundary conditions for Ambiens throughout CFD simulations ow to Figure achieve a cooling effect the office space, a specific day for two different configurations (Source: TAS, Meteonorm)

standard height double

→

open space 2.8m en, and CFD simulations where conducted for Basesided case C (Double sided

ndard height (2.8m) and exposed ceiling 3.4m high configuration wereN External conditions

order to analyze how air flow pattern corresponds to the change in clear Temperature:28.9 C → 280 o

R.Humidity: 41% Wind speed - 4.1 m/s Wind direction - 2040

33oC

13 ACH

Internal

resultant

temperature (TAS)

B dary conditions for the Ambiens CFD simulationsOPTION which were obtained Exposed ceiling double

sided open space 3.4m at 12:00: form the Meteonorm weather file for Friday 7th of September N

External conditions Temperature:28.9 C 0

OPTION A

simulations

340

Wind speed - 4.1 m/s

standard height double

→

norm)

→

R.Humidity: 41% Wind direction - 2040

sided open space 13 ACH2.8m

32oC

Internal

resultant

temperature (TAS)

N CFD simulations for both options (Figure 4.2.18), demonstrate the cooling effect of air flow throughout the External conditions space - temperature reductions of approximate 280 2-3oC on the workspace level were recorded across both o Temperature:28.9 C →

configurations. These air flow simulations show acceptable air flow rates of up to 0.6 m/s throughout the space

R.Humidity: 41%

and indicate the possibility to map different activities according to different wind speeds; e.g. informal meeting

Wind speed - 4.1 m/s

or gathering area could be directed closer to the front window (south or west), while activities which require

Internal resultant Wind direction - 2040 concentration or paper work could be directed towards the back beneath 33oC the upper window, in which less air (TAS) 13velocity ACH will be perceived. Further simulations (see APPENDIX B) which weretemperature conducted for higher wind speeds indicated 8m/s at the highest OPTION thresholdBfor these configurations to allow adequate airflow through the space.

Exposed ceiling double The differences between options and Bspace were 3.4m both in flow patterns and resultant temperatures - the higher sidedA open

space recorded more uniform flow through the space with lower air flow velocity, and lower temperatures with less differentiation between the flow path and the office space boundaries1.

External conditions

Temperature:28.90C

→

R.Humidity: 41%

340

Wind speed - 4.1 m/s Wind direction - 2040 13 ACH

32oC

Internal

resultant

temperature (TAS)

Both thermal and CFD simulations did not take into effect the differences in thermal capacity. ceiling materiality was similar in both options for the

thermal simulations (i.e. mineral ceiling panels)

ure 4.2.18), demonstrate the cooling effect of air flow throughout the

OPTION A Standard height double-sided open space 2.8m

Air speed

Resultant Temperature

OPTION B Exposed ceiling double-sided open space 3.4m

Air speed

Resultant Temperature Figure 4.2.18 CFD simulations for double sided base case with both standard height (2.8m) and increased height (3.4m) for a typical week in September (Source: Ambiens EDSL)

â&#x2020;&#x2018;Â

(a).

(b).

(c).

(d).

(e).

interact, exchange ideas and collaborate; thus the wide range of shared activities was disperse

different micro climatic settings which could allow the whole range - from quite presentation sp

outdoor communal lunch meeting. Singular activities are decentralized and could be performed in m

semi enclosed spaces, or through any of the other shared desks and breakdown areas. Figure 5.3.3 s

wide range of combination between different kinds of activities, these could be distributed according

and thermal considerations, e.g. presentation areas at the depth of the space, less exposed to daylight

gains, break down and informal interaction along the semi outdoor spaces with higher tolerance lev

outdoor climatic conditions and fixed workstations close to the northern windows, with higher exposure and stabilized thermal conditions.

ENVELOPE

The envelope is designed to correspond to different climatic conditions (Figure 5.3.4); openabl

partitions and external movable louvers allow for dynamic exposures between fully extended space 5.3.1 Building form concept evolution the outside, andFigure double protected internal space (with openable windows within the sliding glass form the rigid deep plan to a permeable shallow

natural ventilation theirlayout closed position). planin dynamic

↑

CLIMATIC ADAPTATION OF THE OFFICE BUILDING TYPOLOGY IN THE MEDITERRANEAN

Open position A sunny day during Mid-period

Protected position A sunny day during the hot period Figure 5.3.4

Dynamic envelope design which allows the user to

adapt the space and exposure level by movable partitions, openable windows and adjustable louver-shelf systems

↑

and with the building space to control the balance between thermal and visual comfort levels. In addition to the basic environmental strategies applied (orientation, exposure, ventilation etc.), the application of the adjacent semi-outdoor space towards the south is taking performance further, by serving as a mediator between internal and external conditions, and offers a very good balance between thermal and visual issues; the deep projection addresses glare and excess heat issues effectively, while the adjustable louver-shelf serves as solar protection for the semi-outdoor space and redistributes light towards the depth of the office space. Figure 5.3.5 shows a sequence of scenarios which demonstrates the approach of adaptability towards different activity scenarios and climatic conditions.

DESIGN EXPRESSION The external figure of the building reflects the shift of mind from the sealed rigid glass building, disconnected from its environment, to a new model in which different levels of exposure drive the building’s external image. The correlation between the external layout and the performance becomes complete and corresponds with the local Bauhaus design language in which climatic considerations helped contextualize the modern building trends to the local climate.

Figure 5.2.6 Exterior view of the open air case study showing the design expression of the environmental concepts

THE OPEN AIR OFFICE I DESIGN APPLICABILITY

↑

Mid-period typical day/ Cold-period sunny day

Hot-period typical day

Hot-period afternoon Mid-period hot-day

Cold-period typical day

Architectural Association / Graduate School MSc Sustainable Environmental Design

MSc SED dissertation projects

refurbishing the city a.urban canyon b.urban block c.arcade September 2013 Anastasia Gravani Eleni Kaltsogianni Byron Mardas

AA.

A r

Sch

Sep

REFURBISHING THE CITY

2.4_HUMAN PERCEPTION / TOOLS In order to evaluate the human perception within the urban environment, many outdoor climatic and comfort indexes have been elaborated. Predicted Mean Vote (PMV), Predicted Percentage Dissatisfied (PPD) and Physiological Equivalent Temperature (PET) are the most common used indexes for thermal perception researches. Predicted Mean Vote (PMV) / Predicted Percentage Dissatisfied (PPD) Fanger’s equation for the “Predicted Mean Vote” (PMV) and “Predicted Percentage Dissatisfied” (PPD) is the outcome of a research conducted regarding comfort. A set of environmental variables in correlation with an assumed metabolic rate and clothing level was used, in order to calculate the Predicted Mean Vote (PMV) of a population expressed on a seven-point thermal scale (-3 to +3). The PMV equation rests on steady-state heat transfer which, as stated by Erell et al, hardly ever occurs in everyday life, particularly in the outdoor environment. A state of dynamic thermal equilibrium would best describe the situation of most people. Therefore, according to the same author, when calculating PMV, there might be an error arising from the body’s ever-changing thermal state. This error for a sample of individuals is likely to behave in quasi-random manner, therefore should not be used as an index for assessing outdoor comfort (Erell, 2011). According to Marianna Tsitoura et al, although PMV index might have some disadvantages, it is able to predict the increase or the fall of the comfort votes quite realistically. Predicted Percentage Dissatisfied (PPD) is an index that predicts the percentage of a large group of people who are likely to feel thermally dissatisfied and more specifically feel either too warm or too cold or neutral. The “Thermal Comfort Tool for ASHRAE-55” was developed in the Centre for the Built Environment at the University of California Berkeley, in order to simulate the occupants’ perception in accordance with the monitored values. The parameters which are inserted in the Thermal Comfort Tool are air temperature, mean radiant temperature, air speed, humidity, metabolic rate and clothing level.

figure 2.5_ dynamic relationship between environmental conditions and human perception

REFURBISHING THE CITY

Athens

37.58N

A A tt h he en ns s

23.43E 23.43E

23.43E

37.58N 37.58N

figure 3.1_ Athens location

3 4 4

4 4

3 3

3 2 2

3.1_FORMAL CITY: Athens 3 3

Weather data & climate analysis

1 southern part of Europe, at a 37.9°N Athens is the capital of Greece, located in the Latitude and 23.7°E Longitude, while the average elevation is 45m above sea level. The contemporary city extends across the central plain of Attica basin, surrounded by four mountains: Parnitha, Penteli, Aegaleo and Hymettus and enclosed by the Saronic gulf on its southwest border. According to Köppen-Geiger climatic classification, Greece is characterized by subtropical Mediterranean climate. The national Technical Directive of the Technical Chamber of Greece III (TDCG-3, 2010) has divided the country into four Climatic Zones, based on the heating degree days, with different needs and consumption levels. Athens is located in the 2nd Climatic zone, as shown on Figure 3.2, which is characterized by mild winters and hot-dry summers. 44

figure 3.2_ climatic zones of Greece

ENVIRONMENTAL PERCEPTION THROUGH THE URBAN TISSUE

Figure 3.3 illustrates the annual temperature profile of Athens, as acquired from Meteonorm 7.0. Since a big variation can be identified throughout the year, seasons are distinct. Between January and July average mean monthly temperatures differentiate by 19K thus defining warm, cold and mild periods. Cold period lasts from November to April whereas warm period lasts from June to September. Mild periods can be met around May and October and sunshine duration is high throughout the year, as depicted in figure 3.3. Warm period In the warm period, the average mean monthly temperature raises up to 28.5oC with a mean maximum at 32.8oC . The absolute peak during warm period is given at 38.6oC . Although Meteonorm gives an average of values acquired throughout the length of 5 years, actual temperatures sometimes exceed this value escalating above 40oC . Global radiation during this period, is quite high reaching a peak of 10 KWh/m2 in June and July. Wind also reaches the highest average monthly value during the warm period with a prevailing West orientation, according to Meteonorm data. There is a peak of up to 3.7 m/s during July and August. These values refer though to unobstructed weather data and it needs to be taken into consideration that urban environment reduces the wind speeds significantly. Cold period The cold period has an average mean monthly temperature of 9.3oC with mean minimum monthly at 6.0oC and absolute low -1.5oC during February. As in warm period, in cold also actual temperature can differ from the average given by Meteonorm. Global radiation is reduced to an average of 4 KWh/m2. Average monthly wind speeds remain quite high for this period as well, although the prevailing orientation alters from that of the warm period, coming from a South direction. The average monthly values of relative humidity range from 43% to 70% and follow an opposite diurnal and annual variation to the air temperature. Comfort Figure 3.3 indicates also a comfort band (calculated using EN 15251 2007). It should be pointed out that this comfort band refers more to indoor environments. While the graph depicts a much higher deviation from the comfort band in the cold period, this contradicts with literature and the experiential factor which indicates that warm period is more problematic within the Athenian context.

figure 3.3_ annual weather data for Athens Source: Meteonorm 7

REFURBISHING THE CITY

figure 3.7_ Athens metropolitan area

ENVIRONMENTAL PERCEPTION THROUGH THE URBAN TISSUE

Urban form Current Urban Form The city of Athens has been expanded during the last two centuries towards all directions around the central urban triangle, which have been designed by the architects Stamatis Kleanthis and Eduard Schaubert in 1833. Their proposal intended to enhance the continuity between modern and ancient Athens, by defining the contemporary center in direct correlation with the Acropolis hill and the cemetery of Keramikos. The urban triangle indicated also the location of the new palace of the Bavarian king, which nowadays hosts the Greek Parliament. After the rapid urban growth during the 1960â&#x20AC;&#x2122;s, the urban area of Athens (Greater Athens and Greater Piraeus) extends beyond the administrative municipal city limits (fig. 3.7), with a population of 3.089.698 (in 2011) over an area of 412 km2, which represents one third of the total greek population. According to Eurostat, the Athens Larger Urban Zone (LUZ) is the 7th most populous LUZ in the European Union (the 4th most populous capital city of the EU), with a population of 4,013,368 (in 2004) in an area of 3,807 km2.

figure 3.8_ Athens municipality area Urban density analysis & green spaces

Regarding the contemporary urban tissue of Athens, without analyzing the social and economical factors that dictated its formation, it is characterized by high density areas around the center (fig. 3.8a), with mixed uses organized on the vertical axis. That means that the public uses are located on the ground and first floor level, while the rest of the built volume is commonly used to cover residential or office needs. This distribution of the uses, combined with the Greek building regulations, developed a quite homogeneous urban tissue, consisting of buildings with similar characteristics and spatial principles. Another significant aspect of the Greek capital is the lack of open spaces (fig. 3.8b). It is worth mentioning that total green areas (mÂ˛) to number of residents ratio was significantly low for Athens in 2006, reaching only a value of 2.55. At the same time, in other European countries the values were dramatically higher going up to 9 for London, 27 for Amsterdam and 13 for Berlin (Source:http:// www.minenv.gr/). The basic component of the Athenian layout is the urban block, as a result from the system of continuous building, according to which buildings must be aligned to the front and side boundaries of the plot (GBC 1957-1985). The prevailing geometrical configurations of the urban block are mainly two, the square and the rectangle. The blocks are typically oriented N-S and E-W with deviation of up to 30o in either location (Yannas and Baker, 1983). This is the urban unit that most of the researchers take into account during their studies on the city of Athens. 49

REFURBISHING THE CITY

3.2 URBAN AND ENVIRONMENTAL DIVERSITY Sample stripe In order to conduct a more detailed study in relevance with the microclimatic conditions and the urban features of Athens, a stripe of the urban tissue was defined as sample area. The stripe is located in direct correlation with the urban triangle, as well as with Panepistimiou Avenue, in between the hills of Acropolis and Lycabettus. As depicted in Figure 3.13, within the area of interest, the landscape varies, with an altitude from +90m to +277m. Moreover, the stripe contains a part of both the contemporary and the old city. The distinction between the two parts is based on the different orientation of the tissue, with SW-NE and SE-NW at the contemporary part or S-N and E-W at the old part. Another difference is identified in the height of the building stock, with an average of 2-3floors at the old part and 6-7 floors at the contemporary center. For the ongoing research, special attention will be paid to the contemporary part of the greek capital. The aforementioned part, can be subdivided into two areas, the central uses and the mixed uses. The former is located at the edge of the urban triangle (+90m), being characterized by big blocks and commercial or leisure uses. The latter is expanded towards Lycabettus hill (+110m), hosting commercial uses at the groundfloor and residential or working spaces at the rest of the building stock.

figure 3.12_ Athens Urban triangle & sample stripe

REFURBISHING THE CITY

Sun and wind access As already mentioned, sun and wind access are considered to be catalytic parameters for outdoor comfort. The diversity of the urban fabric has a direct impact on the rate of penetration of solar radiation and wind flow within the urban public space. Consequently, initial analytic studies have been conducted to determine the distinctive patterns of sun and wind access, at street level, within the areas analyzed above (appendix fig.A.7, A.8). Occupancy The area of research is represented by a quite variable group of occupants (fig. 3.13). More specifically, the old part of the city hosts mostly tourists, which means low metabolic rate activities, whereas in the central part of the city, the occupancy patterns are characterized by high mobility rates, especially during daytime. The upper part, towards Lycabbetus hill, hosts both working population during the rush hours, as well as visitors and residents throughout the whole day.

figure 3.13_ sample stripe section

REFURBISHING THE CITY

The

data

input

calculation period

for

the

was:

PET warm

external

temperature 33oC, relative humidity 43% and human characteristics: (1.75m),

weight

height (75kg),

age (35) and sex (male). Radiation for the shadowed areas was considered 130 W/m2, whereas for sunny spots it was used the value of global radiation, equal to 1045 W/m2. Regarding the wind velocity, 0.7m/s was considered

for

protected

areas and 3m/s for the areas exposed to the wind.

figure 3.16_human perception in warm period

ENVIRONMENTAL PERCEPTION THROUGH THE URBAN TISSUE

Human perception

The data input considered for PET calculation during the

cold

period

was:

external temperature 6oC, relative humidity 70%, and human

characteristics

previously described. Moreover,

the

radiation

taken

for

the

shadowed

areas

was

114

/m2,

whereas for sunny spots the value of global radiation was

used

(862

W/m2).

Regarding the wind velocity, 0.7m/s

was

the

value

used for protected areas and 2.5m/s for the areas exposed to the wind.

The complexity of the urban environment, the wide range of conditions and the variety of peoplesâ&#x20AC;&#x2122; reactions, makes its comprehension a complicated task. As introduced more thoroughly in chapter 2, PET index was used in order to evaluate the variable thermal perception outdoors, for the Athenian context. Since PET does not take into account the variation of clothing units, the results given are not considered totally accurate; however they offer an initial approach to the range of thermal perception within the urban tissue. As illustrated in figure 3.16, thermal diversity for a representative warm day and a representative cold day were simulated within the Athenian context. In both cases, the weather data were extracted from Meteonorm 7.0. The four case studies, considered for each day, varied in terms of sun and wind exposure. The overall conclusion is that, during the warm period, being protected from the wind and exposed to the sun can increase sensation of up to 18.5 K, compared to the case of being under the shade and exposed to high wind flow. This result demonstrates that there can be significant variation in perception in warm period within the Athenian context, according to the surrounding urban features. Similarly to the above, a representative cold day was simulated. The conclusion which emerges is that when the occupant is protected by the wind and exposed to the sun the thermal perception rises up 19.3K compared to the base case. Moreover, 10K increase can be achieved even if the occupant is exposed to the wind, as long as there is enough solar exposure occurring simultaneously. What arises, from the above, is that the diversity which exists in the urban environment demonstrates significant potential for improving comfort outdoors. The already existing urban material could be used as an indicator of pleasant and unpleasant cases from which architects and urban designers could be exemplified for future urban design solutions, promoting outdoor comfort.

figure 3.17_ human perception in cold period

REFURBISHING THE CITY

figure 4.28_ Map of Athens, showing the two weather stations, which coincide with the data-logger spots

104

FIELDWORK

fieldwork sample: Contemporary centre of Athens Fieldwork focused on the central area of Athens, in direct correlation with the urban triangle and the zone that will be regenerated across Panepistimiou street, as already introduced in Chapter 3.1 (fig.3.11). This part of the tissue, in case of regeneration, is considered to have a high potential of upgrading the comfort conditions in the center of the city. The urban grid in the area of interest is orientated NE-SW and NW-SE. Within this sample, fieldwork was conducted in urban canyons, urban blocks and various arcades (fig. 4.29). More precisely, three canyons were chosen in each orientation, characterized by different geometry and occupancy pattern (one high traffic road, one low traffic road and a pedestrian street). Furthermore, a series of blocks were measured in order to understand the impact of the various parameters (geometry, orientation, anthropogenic heat and qualitative characteristics) to the thermal conditions, both in the courtyards and the arcades. An initial study focused on the impact of the urban heat island effect on the Athenian center. For the purpose of this study, two data-loggers were installed, one within the center of the city and one in the suburbs, in a low density area(fig. 4.28). Figure 4.27 depicts a difference of 2.5K for the duration of a sunny summer week, between the air temperature values of the suburbs and the central canyons. figure 4.27_ Graph showing temperature difference between city center and suburban area. Difference is indicated bot using data loggers and data acquired by Wundergound.com

Data was also taken from two weather stations of W-underground, located in respect to the above mentioned data logger spots. The difference taken from the weather stations is of 3.6K between the city center and the suburbs. Both the data-loggers and the weather stations depict the urban heat island effect in the center of the Greek capital.

figure 4.29_ Map of the Historic Center of Athens along with the area and the elements where fieldwork was conducted

105

REFURBISHING THE CITY

108

FIELDWORK

Datalogger recordings As

mentioned

above

dataloggers were installed to a series of courtyards and the

canyons area

within

the

study.

Gathered information from a 24 hour measurement was

subdivided

categories

into

two

order

evaluate the outcomes. For that reason, results were grouped into courtyards and canyons. Figure

4.32

illustrates

temperatures as measured within the courtyards. What can be identified is that more enclosed

and

protected

courtyards

(Mpolani,

Ippokratous and City Link) are ~2K lower than outdoor temperature.

The

same

courtyards retain the heat during the night resulting to a 1.5K difference, higher than outdoor temperature. Polis courtyard which has a SVF of ~90% follows outdoor temperature with a high rise during morning hours

affected

solar

radiation. Figure

depicts

air

temperatures

within

arcade

Similarly

4.34 and to

canyon.

above,

the

more enclosed arcade keeps temperatures

1,8K

lower

during the day and 1.5K higher in the night. figure 4.32_ (left top) Air temperatures from Data-loggers within the courtyards. Depicted in the graph are outdoor air temperatures and solar radiation, acquired from wunderground.com

figure 4.33_ (left bottom) Air temperatures from Data-loggers within the Arcades and canyons. Depicted in the graph are outdoor air temperatures and solar radiation, acquired from wunderground.

com

figure 4.34_ Illustrations of the sample blocks where fieldwork was conducted in arcades and courtyards. They are accompanied by their courtyard sky view factors. Source Ecotect

109

REFURBISHING THE CITY

Akadimias street is a high traffic NW-SE orientated canyon, with an average sky view factor of 43% along the canyon and 55% at the crossroads (fig.4.37). The open space around trilogia is highly exposed (point 8 ), reaching 88% SVF. The street level is characterised by commercial uses and offices, however there is no high pedestrian flow due to the unfriendly environment. The surface temperature patterns coincide with the solar radiation profiles, exceeding 50oC around midday. NE Side is highly exposed to solar access around midday, whereas SW side receives direct sun from the morning until the afternoon hours, which leads to a peak increase of 2oC in air temperature (fig. 4.35, 4.36, 4.38 and 4.39).

figure 4.35_ NE facing facade of Akadimias street with the specific spots where measurements were taken and their Sky view factors. Source Ecotect

figure 4.36_ Spot measurements in Akadimias NE side throughout the day

114

FIELDWORK

figure 4.37_ Sky view factors within the urban canyon, within crossroads and the absolute highest of the sample street. Source: Ecotect

figure 4.38_ SW facing facade of Akadimias street with the specific spots where measurements were taken

figure 4.39_ Spot measurements in Akadimias SW side throughout the day

115

REFURBISHING THE CITY

figure 4.65_ measured

126

sample

urban

canyons

FIELDWORK

Fieldwork Outcomes for Urban Canyons Summarizing the results obtained from the fieldwork, in a warm, sunny day the performance within the street level of the Athenian canyons depicts some repetitive characteristics, attributed to their geometrical features and linked with their qualitative characteristics (fig. 4.66). More precisely, in NW-SE orientated canyons (Akadimias str. / Skoufa str. / Valtetsioou str.), there is a higher air temperature difference, depicted between the two sides of the street, allowing for wider adaptive opportunities for pedestrians. Moreover, the wind speed flow was higher than in the SW-NE canyons. Valtetsiou pedestrian canyon has the highest Sky View Factors of the 6 canyons examined, reaching an average of 48% along the canyon and 60% at the crossroads, allowing for the fastest heat dissipation during the afternoon hours, as depicted in the graph. As for the SW-NE canyons (Ippokratous str / Likavittou str / Voukourestiou str), the air temperature profiles of the two sides are homogeneous, reaching higher values than the NW-SE orientated canyons. In comparison with the 6 canyons that have been examined, Voukourestiou street has the lowest SVF values (33% along the canyon and 49% at the crossroads). As a direct result, the direct solar radiation is decreased, allowing for lower air temperature values throughout the daytime. Heat Disspiation though, is quite lower in the afternoon hours. Extended analysis of the urban canyon outcomes is summarised at the fifth chapter.

figure 4.65_ Comparison of the measurements conducted within all the urban canyons

127

REFURBISHING THE CITY

figure 4.67_ Sky view factor in Mpolani Courtyard 29.1%. Source Ecotect

132

FIELDWORK

“Bolani” block is an aggregation

buildings

built

around the 1980’s creating a small open courtyard in the middle (SVF 29.1%) active with commercial uses and an “L-shaped” arcade (DoE 20.4) which connects the courtyard with an adjacent street, that also hosts a variety of commercial uses like restaurants and shops.

BOLANI

BLOCK

Figure 4.68 demonstrates the measurements in “Bolani” block. As it is shown the surface temperatures are in constant correlation with the sun exposure and consequently with the Lux values. The air temperature in the morning is low in the adjacent urban canyon in measurements 1 and 2 since it is totally protected from the sun exposure at this specific time of the day. Values increase by 1K reaching up to 31 oC while entering the arcade (spot 3,4 and 5). Finally, air temperature decreases by 1K inside the courtyard and rises again to 31.5 oC in the adjacent to the courtyard urban canyon, which is exposed to the sun during the morning. The performance during midday changes significantly since the sun exposure has increased remarkably in both urban canyons (spots 1, 2 and 8, 9) and inside the courtyard (spots 6 and 7) affecting the air temperature in those spots likewise reaching a high peak of 36.5 oC . Contrariwise, the air temperature inside the arcade is at 33 oC creating a thermal diversity of 3.5 K with the urban canyons and the courtyard. The measurements taken, during the evening and night visits, display high homogeneity in air temperature and Lux values which indicates that as the sun exposure is decreasing, the air temperature is less affected by the diversity in urban morphology. The PPD results are low (under 20%) for “Bolani” block throughout the whole day, however, the arcade indicates higher percentages, up to 25%, compared to the courtyard at midday. This could be due to the low wind velocity inside the arcade which affected the perception of heat increasing that way the feeling of discomfort. (fg. 4.70)

figure 4.70_ PPD analysis of Mpolani throughout the day. Source ASHRAE comfort tool

135

REFURBISHING THE CITY

figure 4.80_ Perception of thermal walk participants Source: Questionnaires

figure 4.82_ Spot measurements done during thermal walk

150

FIELDWORK

figure 4.81_ Map showing the thermal walk route and the spots evaluated as most pleasant and most unpleasant

151

REFURBISHING THE CITY

urban canyon

figure 5a.32_pedestrian gallery : configuration of structural elements

192

.urban block

.arcade

DESIGN GUIDELINES

figure 5a.33_pedestrian gallery : adaptive strategies

193

REFURBISHING THE CITY

urban canyon

figure 5a.34_Voukourestiou canyon / SW view / midday 21st of June

DESIGN GUIDELINES

REFURBISHING THE CITY

.urban canyon

urban block

.arcade

figure 5b.19_ Renders of the two cases showing the difference in shadow and lighting quality.

0 :0

0 1:

Panel Roof

: 16

figure 5b.20_ The three conditions of the grid-panel roof where different patterns achieve permanent protection to the problematic area. source Grasshopper

interface Rhino

What makes the grid case even more appealing, is the fact that the percentage of open tiles can be modified according to the needs, therefore offers a variety of solutions, from fully exposed to fully protected and different levels of protection. The aforementioned 20% of open tiles refers to the part of the roof that needs to be closed according to the shading pattern analyzed in figure 5b.12. The rest of the roof can have much higher percentage of open tiles in order to enhance the lighting conditions inside the courtyard and to not compromise the conditions of the adjacent indoor spaces. These parts of the roof could either be a fixed pattern of 70% open tiles or could follow the rotating concept of the main body. Of course the rotating panels would increase even more the adaptability and will also serve the indoor conditions as well. In figure 5b.20 different patterns of closed and open tiles are illustrated. These are generated using Grasshopper for Rhino where a random 20% of the tiles are opened on the area of interest, according to the hourly profile introduced in figure 5b.12. The rest of the roof has a percentage of open tiles of 70%. It can be seen that the area of interest, marked inside the red, lies always within protection from solar radiation due to the adaptability of the roof. As mentioned before and also as illustrated in figures 5b.21 and 5b.22 the different solar protection and the shadow patterns that are created within the courtyard provide the possibility for a variety of public activities to take place.

210

figure 5b.22_ (left) Render of the gridpanel case using a coverage of 40%

DESIGN GUIDELINES

figure 5b.21_ Render of the grid-panel case using a coverage of 80%

211

REFURBISHING THE CITY

.urban canyon

urban block

.arcade

30%

March 4390 April 5604 May 6725 table 5b.1 calculation of energy produced June 7192 July 7238 PAugust eriod K 6538 w h September 5324 Janyary 2330 October 3750 February 2718 November 2325 March 4390 December 1962 April 5604 May 6725 Annual 5 6 0 9 6 Kwh June 7192 July 7238 August 6538 September 5324 October 3750 November 2325 December 1962 Annual

30%

5 6 0 9 6 Kwh

figure 5b.23_ (left) Illustration of the PV panel case.

30%

80%

30%

4 6 7 m 2 o f p a n e l s

30%

80%

4 6 7 m 2 o f p a n e l s

figure 5b.24_ (left) Dimensions and coverage of the roof parts in order to calculate area of closed panels.

5b.5 COST & ALTERNATIVE SOLUTIONS In any case, this scenario, of the individual rotating tiles, is much more complicated and of course costly. Therefore another option to this case is for the tiles to consist of solar panels that will produce energy when closed. Energy produces will be enough to power their own movement and in an optimum scenario the remaining energy could be distributed to the occupants of the block. (fig. 5b.23) With a 30% closed tiles on the roof and 80% specifically on the area of interest, each part of the day, an area of ~467 m2 can be calculated within the courtyard of the case block almost every part of the day. Of course the area can be altered within the limits of the adaptive opportunities as mentioned before. But in the case set as a base scenario this area can produce substantial energy, even though the panels are horizontal and not tilted as the optimum condition of PV panels is. Table 5b.1 indicates a brief calculation of the KWh that this installation can produce, calculated using various methods available on the internet. Of course, the installation of all these small panels will make the project even more expensive and although there will be long-term benefits (in around 5-6 years), occupants will tend to dishearten it. Therefore a much cheaper case was introduced that is considered much cheaper and works in the same way. In this case panels are created by cheap material such as cane which can be found in Greece. This material can be considered also much eco friendlier since it is a natural material with availability within the country. Of course the urban area does not host any cane fields therefore they need to be transported from rural areas, but in the same way every material that is used in construction inside the city, is bound to be transferred from elsewhere. (fig. 5b.25) As already mentioned, this “cheap” case, works like the PV panel case in terms of protection. Having a percentage of open and closed tiles to create the shading needed. For this option to become even friendlier, cheap and more interactive, the operation can be done manually from bellow according to the needs of the occupants. For this to be done more easily the grid is slightly larger so the number of the movable panels can be reduced. The operation can be done directly from ground level using ropes and this will give the occupants the perception of higher control over their adaptability. (fig. 5b.26) 212

figure 5b.25_ Cane panel grid

figure 5b.26_ Render of the “cheap” case showing the interaction of the occupants.

DESIGN GUIDELINES

213

REFURBISHING THE CITY

.urban canyon

.urban block

arcade

d.VOUKOURESTIOU_STR.

c.MONETARY_MUSEUM

b . C I T Y. L I N K _ B L O C K

a . B O L A N I _ B L O C K

b. a.

250

REFURBISHING THE CITY

254

.urban canyon

.urban block

arcade

REFURBISHING THE CITY

.urban canyon

.urban block

arcade

figure 5c.22_Perspective view of the intervention applied into an already existing arcade (City Link).

258

DESIGN GUIDELINES

Visualisation

figure 5c.23_Perspective view of Voukourestiou Str. with the intervention expanding on the pedestrian street.

259

Architectural Association / Graduate School MSc Sustainable Environmental Design

MSc SED dissertation projects creative refurbishment of historic housing in Santiago de Compostela

September 2011 Patricia Linares

Climatic areas in Galicia according with temperature and precipitation <8

8-10 10-12 12-14 >14

Annual Precipitation (mm)

< 800 800-1000 1000-1200

A Coruña

1200-1400 1400-1800

Lugo

>1800

Annual Mean Temperature (ºC)

Santiago

III Ourense

VII Vigo

VI Classification according to Temperatures

Climatic areas in Galicia according with temperature IV and precip Figure viii.7. After Martínez et al. (1999)

40 (km)

< 800

Characteristics of the site (Concello de Santiago)

8-10

800-1000 1000-1200

A Coruña

1200-1400 1400-1800

Lugo R ío

River

el a Sar

Santiago de Santiago Compostela

>1800

Annual Mea

Peak Historic centre

Lavacolla

III

Wind direction Administrative boundaries

R ío

Ourense

Sa r

VII Vigo

VI 1

Figure viii.8. After SITGA · 19 ··

Figure viii.7. After Martínez et al. (1999)

10 (km)

Classification a to Temp

1400-1800

Lugo

>1800

IV R ío

Annual Mean Tem River

el a Sar

Santiago

Santiago de Compostela

Peak

III

Historic centre

Lavacolla

Wind direction

Ourense R ío

Administrative boundaries

VII

Sa r

Vigo

Classification accord to Temperatu 10 (km)

Figure viii.8. After SITGA

Figure viii.7. After Martínez et al. (1999)

19 ··

Characteristics of the site (Concello de Santiago)

R ío

el a Sar

Santiago de Compostela

Historic ce

Lavacolla

Wind direc

Administrative bounda R ío

Sa r

Figure viii.8. After SITGA

Impact of street width on non-passive zone obstruction angle Non-passive zone (%)

3 5 7 9 12 (m)

100

60 40 20 0

‘non-passive’ zone

3m (72º)

5m (62º)

7m (53º)

9m (46º)

12m (40º)

Street Width (Obstruction Angle)

Figure viii.20

Impact of floor height on non-passive zone

Non-passive zone (%)

100

‘non-passive’ zone

89 79

80 60

40 20 0

Ground F (72º)

Floor 1 (65º)

Floor 2 (48º)

Floor 3 (23º)

Floor Height (Obstruction Angle)

Figure viii.21

Impact of building depth on non-passive zone

8 16 24

(m)

ground floor first floor second floor

Non-passive zone (%)

100 80 60 40 20 0

24m GF

16m Building Depth (m) F1

‘non-passive’ zone ground floor ‘non-passive’ zone first floor ‘non-passive’ zone first floor

third floor Figure viii.22 · 25 ··

‘non-passive’ zone first floor

8m F3

Case Study Rúa Nova 22

Rúa

Nova

Urban context and building description

24’00m 7’45m 100m

50m

Building Data Floor studied Nº occupants

Floor Area (m2) Galería area (m2)

Window-to-floor R (%)

Heat loss coefficient (W/m2K)

2nd Floor 2

147’5 13’4

13.95 %

2’04

Plan 2nd Floor V1 V2

V3 N

V1 (street facade)

V2 (patio)

Figure ix.1. After Barones et al. (2011) · 34 ··

V3 (living-room)

V4 (galería)

V5 (kitchen)

Population in block Rúa do Vilar - Rúa Nova Block population = 156 inhabitants Dwelling surface = 16613’90 m2 Density = 106’50 m2/inhabitant

4 5

<1-24 years old

8-10

25-64 years old

11 13

65-99 years old

P o p u l a t i o n Rúa do Vilar (impares)

do V

ilar

21 23

22 24

Rúa

29 31 33

26 28

Nova

37-39

Rúa

51-53-55

40 57

11 20

42 44

51 46

<1-24 years old 25-64 years old 65-99 years old

P o p u l a t i o n Rúa Nova (pares) Figure x.3. After Martí (1995) and Censo de población de Santiago (2011) · 50 ··

Residential buildings in Rúa do Vilar <1-24 years old 25-64 years old

nº3

65-99 years old

Building Residential Area (m2) - attics not included -

nº5

nº7-9

nº11 nº13

486,00

534,12

nº15

571,74

574,30

11 13

nº17

nº19

nº21

162,92

nº43

391’04

1 4

nº33

nº35

595’77

nº37-39

nº41

811’53

37-39

29 31 33

nº45 47 49 51-53-55 nº57 nº59

315’6 553’3 253’8

43 45

4 2

235’04 272’64

21 23

nº23 nº25 nº27 nº29 nº31

668,72

4749

837’87

nº61

384’93

nº63

nº65

nº67

340

0 10

51-55

Figure x.4. Source: Censo de población de Santiago (2011) ·· 51 ·

Increase in solar access (Case1) occupancy = 15 hours 1 = masonry wall 2 = timber wall 2

occupancy = young single

Case 1 (BC4 + size patio)

10m

Floor Area Patio Area

Infiltration Ventilation (air fresh requ)

Annual Internal Gains Weeday Internal G

(m2)

(ach)

(kWh/year) (Wh/day)

153’47 45’32

0’850 0’080

3640,875 9975

U-v masonry wall U-v timber wall U-v Windows U-v Roof (W/m2K)

0,54 0,56 1,81(day)/1,12(night) 1,31

Window Ratio Non-passive Zone (%)

21’11 43’99

Heating load (kWh/m2year) 160.00 140.00 120.00

21.17 %

100.00 80.00

57.45

60.00 40.00 20.00 0.00

BC BC

BC1

BC2

B1 (airtight)

B2 (shutters)

BC3

B3 (Uvwind)

BC4

B4 (Uvstone)

B5 (bigpatio)

B6 (2houses)

B7 (galería)

B8 (newRoof)

Loads Breakdown Annual (kWh/m2year)

Winter (kWh/m2season)

7.77 51.69

-65.29

Solar

sse

Figure xi.5. Source: TAS · 63 ··

Heat Loss Conduction

G Lo

3.87

Internal

16.48 -47.76

-19.41

Infiltr. + Ventilation

-13.75

Patio 0 (BASE CASE) Figure xi.6. Source: ECOTEC · 65 ··

Patio A

Patio B

Patio C (CASE 2)

Patio D

% DF

7’28 % 4’73 % 3’42 %

DF %

6’59% 4’48% 3’10%

DF %

5’34% 3’80% 2’48%

% DF

5’16 % 3’44 % 2’34 %

% DF

3’90 % 2’94 % 2’21 %

Parametric studies on solar access through the patio

Average daily radiation in winter

(Wh/day)

South W

478’1 700’0 531’0 499’3

E 753’6

(Wh/day)

South 1015’9

W 700’0

N 747’3

Figure xi.7. Source: ECOTEC

Daylight Factor (%)

DF (%)

6.71

1.21

0.00 0.40 0.80 1.20 1.60 2.00 2.40 2.80 3.20 4.00

0.69

0.51

0.91

6.60

0.45

DF (%)

7.18

2.01

0.00 0.40 0.80 1.20 1.60 2.00 2.40 2.80 3.20 4.00

1.51

1.42

Figure xi.8. Source: ECOTEC

·· 66 ·

Dwelling surface reduction (C2) occupancy = 15 hours 1 = masonry wall 2 = timber wall 1

occupancy = young single

10m

Case 2 (C1+dwelling surface)

Floor Area Patio Area

Infiltration Ventilation (air fresh requ)

(m2)

(ach)

(kWh/year) (Wh/day)

70’73 45’32

0’750 0’173

3640,875 9975

Annual Internal Gains Weeday Internal G

U-v masonry wall U-v timber wall U-v Windows U-v Roof (W/m2K)

Window Ratio Non-passive Zone (%)

0,54 0,56 1,81(day)/1,12(night) 1,31

22’90 47’73

Heating load (kWh/m2year) 160.00 140.00 120.00

26.86 %

100.00 80.00 60.00

42.02

40.00 20.00 0.00

BC BC

BC1

BC2

B1 (airtight)

B2 (shutters)

BC3

B3 (Uvwind)

BC4

B4 (Uvstone)

B5 (bigpatio)

B6 (2houses)

B7 (galería)

B8 (newRoof)

Loads Breakdown (kWh/m2) Annual (kWh/m2year)

Winter (kWh/m2season)

8.27 -69.48

55.95

Solar 33.02 35.39

ses

· 67 ··

ins

Los

Figure xi.9. Source: TAS

8.32 7.81

Internal Heat Loss Conduction

-52.18

-21.25

Infiltr. + Ventilation

-14.12

(xii.3) Architectural implications and accessibility The strategies described so far might result in an alteration of the original house, affecting openings, wall finishing and also layout. Figure xii.10 illustrates the volume of Case 2+nR, which shows the spacial alterations commented so far. Some distributions schemes are studied in figure xii.11, for every Case. Adversely to traditional practice, open layouts may be preferable, in order to maximise daylight. As mentioned before, location of doors is preferable in the southern area, which has been proved to be the darkest (chapter x.3). In some houses, the stairs are placed within the patio. Traditionally, they are wide and made of dark wood, thus reducing the solar access of the lower floors. If the stairs were to be refurbished, their position and design should encourage the solarity of this space. Improvement of accessibility, which is a big handicap of old buildings, should also be considered, provided that a bigger patio favours the location of an elevator. However, this would also have a negative effect on the daylight of the houses (see patio B in figure xi.6). A compromise should be achieved between environmental performance and architectural functionality. Case C2+nR has been rendered to visualize the spacial quality of the domestic spaces (figures xii.12 to xii.15).

Case C2+nR

Figure xii.10 路 82 路路

Distribution shemes Base Case

Case 1 (with improved accesibility)

Case 2

Case new Roof

Figure xii.11 路路 83 路

Figure xii.12

Figure xii.13 路 84 路路

Figure xii.14

Figure xii.15

路路 85 路

Architectural Association / Graduate School MSc Sustainable Environmental Design

MSc SED dissertation projects Keeping the Nomad adaptive bedouin house in Wadi Rum

September 2013 Rawan Qobrosi

Fig. 2.4 Bedouin Camel herds. (Source: Faegre, 1979)

2 1. The tent constitutes the principal form of dwelling or its use is extremely widespread. 2. Widest extent Fig. 2.5 Geographical distribution of the Black tent. (Source: Drew, 1979)

Fig. 2.6 The Arabic and Persian Black tent Tribes. (Source: after Faegre, 1979)

Fig. 2.9 Woman of the Hwaitat Bedouin, South of Jordan sewing strips for a tent. (Source: Drew, 1979)

Fig. 2.8 Tent with Loom , South of Jordan. (Source: Drew, 1979)

Fig. 2.9 Woman of the Hwaitat Bedouin, South of Jordan sewing strips for a tent. (Source: Drew, 1979)

Fig. 2.8 Tent with Loom , South of Jordan. (Source: Drew, 1979)

Fig. 2.10 View of goat hair strips on the roof cloth and detailed sewn edge to edge strips.

Goat Hair Strip 60-80cm

Women’s Side

Men’s Side

Fig. 2.10 View of goat hair strips on the roof cloth and Tension bands detailed sewn edge to edge strips.

Wooden Poles Walls; Ru’ag

Hemp Rope Goat Hair Strip

Fig. 60-80cm 2.11 Detailed plan of Um Omar tent, and a section through the middle. Women’s (Source: after Faegre, 1979)

Side

Tension bands

Hemp Rope

Men’s Side Stay Fastener

Tension Band

Wooden Poles Walls; Ru’ag

Front

the goat hair fabric.

(Source : Ragette, 2006) Women’s Side

Men’s Side

Mattress Rolled up bedding

Common Space Hearth Kitchen

Child hammock

Hearth

Guest’s Space

Loom

Outdoor Kitchen

Fig. 2.26 Bedouin tent layout and daily activities expansion to the front space.

| 1 7

Fig. 2.15 Expanded Qata, and fixed back wall for the Northern wind protection. (Source: Faegre, 1979)

Expanded Qata

Fig. 2.16 Closed front openings. (Source: Photo by G. Wilson)

Fig. 2.17 Expanded Qata. (Source: after Lockerbie, 2013)

48.8째C 30.7째C

500lux 97000lux

Fig. 2.18 Surface temperature of shaded red sand by the tent and exposed sand.

Fig. 2.20 Lowered roof Bedouin South Jordan. (Source: after Lockerbie, 2013)

Fig. 2.19 Illuminance levels of the outdoors and internal space of the tent at 12:45pm.

Fig. 2.21 Um Omar added cloth for extra shading.

| 1 5

Fig. 4.5 Front façade, main entrance Mastaba. Fig. 4.3 Rum Village aerial view with Mohammad Zalabia house identified. (Source: after Bing maps)

Fig. 4.5 Front façade, main en North façade, Family Room entrance. Fig. 4.3 Rum Village aerial viewFig. 4.6 with Mohammad Zalabia house identified. (Source: after Bing maps)

Fig. 4.3 Rum Village aerial view with Mohammad Zalabia house identified. (Source: after Bing maps)

Fig. 4.4a Mohammad Zalabia house with the offsets from the boundary walls. Fig. 4.7 West façade.

Fig. 4.6 North façade, Family 1 0 m

Family Room

Majlis

Family Majlis

Fig. 4.8 South façade.

1 0 m

Fig. 4.4b Mohammad Zalabia house plan.

Fig. 4.4a Mohammad Zalabia house with the offsets from the boundary walls. | 4 5

Fig. 4.4a Mohammad Zalabia house with the offsets from the boundary walls. Fig. 4.7 West façade.

Resultant Temperature (째C)

Goat Hair + Tilt Roof

22nd Jan

23nd Jan 24th Jan Fig. 5.10 The resultant temperature of the Bedouin house wit tilted goat hair roof.

25th Jan

22nd of January at 12pm To = 14.1째C, Inlet=0.1m/s

54.7째C 48.5 42.8 36.9 30.9 25.0 19.0 13.1

Fig. 5.11 The resultant temperature through the Family Room, 22nd of January, at 12pm. (Source: Ambians, Tas EDSL)

Resultant Temperature (째C)

Goat Hair + Tilt Roof | Insulation

22nd Jan

23nd Jan 25th Jan 24th Jan Fig. 5.12 The resultant temperature of the Bedouin house with goat hair tilted roof and insulation.

| 6 7

6.1 D e s i g n P r o p o s a l Integrating the adaptive Bedouin culture with sustainable architecture is essential. The idea is to â&#x20AC;&#x153;dissolveâ&#x20AC;? some of the Bedouin passive habits that are effective and desired or familiar by the Bedouins to provide a responsive Bedouin house. Layout and Boundary walls The Bedouin house should be oriented with Southern orientation (see Fig 6.1). The Hosh should be on the Northern side, so the desired Northern breeze can reach into the house across the Family Room (see Fig 6.2 and 6.3). Moreover, in order to minimize the negative impact of the boundary on the wind flow, an adaptive boundary is proposed. According to Jones (2008), the height of the barrier will create a wind shadow of four times its height. Therefore, introducing an adaptive boundary where its height can be reduced from the original 2.8m to 2m, can help the wind to flow into the house in the hot period, or raised back to 2.8m to protect from the cold winds (see Fig. 6.5). Moreover, having permeability in the boundary can also help in the wind flow patterns in the Hosh (see Fig. 6.4).

EAST

Fig. 6.2 Barriers and their effect on wind flow. (Source: Metric Handbook)

WEST Fig. 6.1 Bedouin house preferred orientation.

H 3.2m Fig. 6.3 Existing proportions.

2.80

2.00

Fig. 6.4 Typical wind flow patterns. (Source: Metric Handbook)

8 2 |

Fig. 6.5 Adaptive boundary wall height.

ns getting their dinner out of the Zarb. (Source: Abadi, 2012)

Fig. 6.7 Section through Family Room Windows.

Fig. 6.8 Illustra

rough Family

Fig. 6.8 Illustrations of the Windows opening application.

be movable to help more with passive solar heating from the South opening, and prevent obstruction of the air movement into all the spaces in the hot period (see Fig. 6.12).

Northern West Winds

Fig. 6.9 Illustrations of the effect of oblique winds to the openings on cross ventilation. (Source: Metric Handbook, 2008)

South West winds Fig. 6.10 Oblique winds on the Bedouin House openings.

Fig. 6.11 Illustrations of the effect of adding wing walls. (Source: Metric Handbook, 2008)

Fig. 6.12 Adding adaptive wing walls and movable internal wall.

8 4 |

Shading Bedouins usually water the front entrance â&#x20AC;&#x153;Mastabaâ&#x20AC;? to make it more comfortable for evening use and sleep under an open sky. To reduce the use of water and preserve the habit of the daily migration, the ground can be shaded during the hot hours of the day with the use of weaved goat hair cloth strips, which preserves the system and scale of the loom as shown in Fig. 6.13. These same pieces that are handled by the women can be rolled and fixed with similar steel bolts used in the loom weaving as illustrated in Fig. 6.14 and 6.15.

Fig. 6.13 Women weaving on the loom. (Source: Drew, 1979)

Fig. 6.14 Section through the ground shading.

Fig. 6.15 The shading application concept taken using the same sizes of cloth breadth and fixed with steel bolts at the edge.

| 8 5

provide privacy for the lower Majlis windows when needed (See Fig. 6.18). Moreover the mats can be used as a local adaptive internal shading element in the Family Room to help reduce glare and provide privacy (see Fig 6.19).

Fig. 6.15 Reed mats used as shading element in shop in Rum Village.

(Source: Arco, 2010)

Fig. 6.16 East and West faรงade Shading Device application.

Fig. 6.17 South faรงade shading device application.

Fig. 6.18 Majlis Windows shading device application.

Fig. 6.19 Local adaptive internal shading application for privacy and glare, shown with the Human Sensitivity image.

8 6 |

Fig. 6.21 Family Room in the hot period during midday at 12pm. Maximum shade.

Fig. 6.22 Family Room in the hot period, at night. Roof is open to the clear sky.

Fig. 6.23 Wing walls added similar to how the Qata in the tent extends on the stay ropes to protect from the South-West winds.

Fig 6.24 Wing wall added to help direct the North-West winds into the Family Room.

Fig. 6.25 Family Room in the cold period, buffer space is added and coupled.

Fig. 6.26 Family Room in the mild period, some direct solar gains by opening part of the roof.

Fig. 6.27 Parents bedroom coupled with children bedroom for extra solar heating and keeping the current family behaviour where they sleep in one space in winter by applying movable walls. | 8 9

9 2

Fig. 6.31 Exploded 3d of the conceptual design model.

2 |

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