Document [original]

German-Iranian Research Project

Young Cities

Developing Energy-Efficient Urban Fabric in the Tehran-Karaj Region

www.youngcities.org Energy-Efficient-

Homes

Designing Energy-

Efficient Architecture

in an Urban Context

Philipp Wehage, Annette Wolpert, Elke Pahl-Weber

Young Cities Research Briefs | 10

The volume before you results from the federal funded research

project “Young Cities – Developing Urban Energy Efficiency”.

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Technische Universität Berlin

FG Bestandsentwicklung und Erneuerung

von Siedlungseinheiten

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10623 Berlin | Germany

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Preface .................. 3

1 Introduction ................ 4

2 Research methodology: a research by design process .....10

3 Design strategy – analysis and design approach ......16

4 Design solutions ...............19

5 Perspectives ................42

6 Architectural plans ..............45

7 References .................52

Table of Contents

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Preface

The “Energy-Efficient-Homes” present a “research by design” based process

for sustainable housing in the MENA (Middle-East North-Africa) region

based on the case study for Hashtgerd New Town in Iran.

The pilot area of the case study, the “Shahre Javan Community”, is sit-

uated in Hashtgerd New Town, about 65 km north-west of Tehran. Within

the existing framework, the program provides a housing quarter for about

8,000 inhabitants in about 2,000 dwellings, including the necessary social

infrastructure.

The “Energy-Efficient-Homes” highlight the potential of spatial design

regarding energy- and resource-efficiency. The task for urbanism and archi-

tecture was to develop spatial strategies and measures to maximize the use

of passive energy impact and to minimize the consumption of natural re-

sources. The final design is an adaptation of the process findings to the site

specifics of the pilot area. It shows the design scenario for one urban unit for

about 250–300 inhabitants.

Due to the fact that about 70 % of the whole MENA region is classified

into arid and semi-arid climate and that the Islamic rooted society consti-

tutes the socio-cultural context of a wider supranational region, project re-

sults gathered against this background, can be used for further dissemina-

tion through e. g. transfer and adaptation to other locations in the region.

The study was conducted by the “Young Cities” Project at TU Berlin in

the research dimension “Urban Design and Architecture”. It was published

in the “Young Cities Paper Series, Volume 04” of TU Berlin in 2013. The au-

thors would like to thank Cornelia Saalmann of the Project Centre at the TU

Berlin to enable this publication and Prof. Elke Pahl-Weber and Prof. Peter

Berten for their expertise and support.

Philipp Wehage, Annette Wolpert

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

1 Introduction

Housing is the central, if not the original objective of architecture. The hu-

man need for a climate adapted envelope and the areal formulation of the

smallest social unit has always followed specific social and spatial visions.

In a fast growing society like Iran, the demand for mass produced housing

requires efficient strategies for the planning and construction processes.

These challenges in mind, a typological approach for the design of an en-

ergy-efficient housing architecture, that derives from the planning process

directly, has been chosen as the appropriate method. This “research by de-

sign” method provides the opportunity to apply a typological approach to

the development of an energy-efficient estate. The pilot area selected is the

“Shahre Javan Community”. Here, the “research by design” approach serves

as a tool to develop design solutions that incorporate the urban context of

the pilot area. Respecting the aims of the urban design and its relevance con-

cerning the spatial arrangements for energy efficiency, the housing typolo-

gies follow the needs of the local culture, which means creating places for

privacy in a compact urban context. The design of residential architecture is

therefore the outcome of simultaneous aims, those for energy efficiency and

those concerning the spatial need for privacy.

1.1 Goals and strategies

Supposing the general scientific principles for energy efficiency as well as the

need for privacy applied in the pilot project are comparable to regional de-

mands, then the design resulting in the “Shahre Javan Community” project

does not just stand for this specific location. Despite the fact that design solu-

tions are always connected with the “genius loci”, these are in fact transferable

to other regions in the Middle East as they respect the general climate con-

ditions and the socio-cultural demand in the region. Geological (e. g. earth-

quake resistance) and geographical (e. g. topography) aspects that are specific

to each site need to be reflected and adapted to local demands. Therefore, the

aim of this typological work is not to give fixed answers for mass housing in

the whole region, but to give a catalogue of planning measures and processes

that can be adapted to specific applications and standards.

The research process involved in developing the energy-efficient archi-

tecture for the “Shahre Javan Community” pilot project is characterized by

the relation between the general scientific principles (physical and techni-

cal) and the local and regional conditions (climate and site). The housing for

Iran’s new towns demands an analysis of the country’s present situation in

regard of urban design and architecture and the potentials of vernacular ar-

chitecture for future developments in semi-arid regions. By analysing the

spatial formulations of architecture and urban design regarding energy ef-

ficiency, it was possible to categorize suitable organizational forms. The en-

ergy efficiency value of the general architectural and urban findings on the

site with its specific features concerning climate and topography has been

adjusted to the socio-cultural context. The result of this research is formu-

lated in a catalogue of architectural criteria as an approach for further de-

sign solutions.

1.2 Housing in the orient and Iran

1.2.1 Housing in the orient – tradition and today

In the architectural traditions of Iran and the Orient, a home is characterized

by the demand for absolute privacy. Following the hierarchy of public and

private space in urban designs, the following consequences can be outlined:

Integrated in the hierarchical definition of space, the house represents

the final step into the private realm (Wirth, 2000, p. 325 ff). The introver-

sion of the traditional courtyard house is one spatial expression of the need

for tranquillity and intimacy. This hierarchical system of space in urban de-

signs is accepted and also pursued in the organization of the house. Areas

for access, guests, services and family-life are integrated in a well-defined

floor plan around one or several central courtyards which form the centre

of the house (Edwards et al., 2006, p. 21 ff). The layout illustrates the hierar-

chical system from public to private areas inside the dwelling (Bianca, 1991,

p. 196 ff). The open spaces attached to the courtyard houses, such as access

paths, are minimized as the focus is on the spatial quality of private space

Traditional

sense of place

inward looking space

Western

sense of place

outward looking space

Fig. 1: The sense of place according to S. Manzoor

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

inside the house. The introverted housing scheme allows for a climate-sen-

sitive urban arrangement, which is characterized by compactness through

the attachment of units in closed coverage. Elements for ventilation, such as

wind towers, optimize the climate conditions, especially in hot arid regions

(Edwards et al., 2006, p. 155 ff.).

The adaptations of modern housing typologies in the 20th century have

transformed the dwelling into an extroverted volume in a Western style. The

definition of space, as known in the introverted traditional style, has been

turned inside out. This break in tradition has made available the advantage of

exposition to light and air on the outside by opening up the façades, and there-

fore the possibility of creating multi-storey buildings.

The former organizational scheme of the neighbourhood has been

transformed – from a horizontal to a vertical arrangement. The consequence

is that the inhabitants have to react by defining a new spatial organization or

by changing their habits. The stairway, for example, has been transformed

into a vertical “dead end” and defined as a semi-private space according to

Islamic tradition (Wirth, 2000, p. 398 ff).

But the separation between private indoor and public exterior space was

disturbed by opening up the façades. The informal result of this spatial turn-

around is that the apertures are now covered up with curtains. The private

open areas attached to the façades and facing onto the streets, such as gar-

dens, balconies and loggias, are not frequented due to their visibility from

the public space and have therefore developed a backyard character. They

are often used for storage or technical supplies (e. g. air conditioning equip-

ment). On an urban design level, this relation of the façade to the exterior

creates relic open spaces in the Islamic regions of the Orient (Diba, 2002).

The extroverted housing schemes in new towns often apply linear build-

ing arrangements, comparable to housing developments in the Western

world. The broad and wide linear urban space between the building volumes

appears as a relic negative space with a lack of quality, because there has

been no cultural adaptation.

The contradiction between privacy according to a traditional Islamic

understanding and the Western-style vertical housing typology has not yet

been addressed, neither the urban principles of developments in new towns

nor in the renovations of existing structures in the large cities like Tehran

or Karaj.

1.2.2 Housing in Hashtgerd New Town

The common housing typology for the medium density of Hashtgerd New

Town is based on the orthogonal layout of the urban masterplan (Wehage

et al., 2012, p. 39 ff). This system orients buildings in a north-south direc-

tion, such that access to the buildings is either from the north or the south.

The plots are arranged in a rectangular layout without regard to topography.

The common plot width is 15 to 18 m. The common plot area is about 600 m².

The position of the building volume on the plot is defined by regulations on

distance, which are based on light exposure, privacy aspects and regulatory

plot coverage. Ignoring light orientation, the staircases are often positioned

in the street-side façades. This type of attached building (“closed coverage

type”) leads to a linear structure of building volumes. The linear arrange-

ment of buildings leads to uniform linear open spaces oriented towards the

public and private sides of the houses (Fig. 2–3). The only spatial measure for

defining the private open space is the enclosure of the plots with walls. Thus

the spatial boundaries of the north-south oriented open spaces, e. g. streets

and parks following the topography, are not properly defined. Furthermore,

the ends of the linear building structures are simply cut off with a closed

shear wall, lacking any architectural corner design.

Fig. 2: Housing blocks in Hashtgerd NT –

view from the south

Fig. 3: Housing blocks in Hashtgerd NT – site plan

1.3 Energy-efficient urban design and architecture

The position and configuration of the building volume and its orientation to

the sun is an important factor for energy-efficient architecture. Because of

its relevance concerning the spatial organization on an urban scale, defined

for example by access situations and morphological settings, the position in

the urban fabric must be considered.

The main aspects of the urban context are determined by the orienta-

tion, as a factor for passive energy gain, and the compactness, as a factor for

minimizing energy loss through the thermal envelope (Hegger et al., 2008,

p. 62 ff).

The ideal volume for the use of solar incidence, as the main passive en-

ergy yield, is characterized by a glazed façade for all main rooms oriented to

the south and a more closed façade to the north enclosing secondary rooms.

The north-south orientation leads to large areas with an east-west direction

and small depths in the north-south direction. It is for this reason that this

layout is not practical for compact urban schemes.

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

1.4 The climate context

The semi-arid climate in the region of the pilot project is characterized by

warm and dry summer periods, with extreme temperatures of more than

35 °C during the day and colder and more humid winters with occasional

frost periods (FU Berlin, 2010). Because of the extreme seasonal tempera-

ture range, energy for cooling as well as heating is required to provide ther-

mal comfort in the building. The significant difference between the day and

night-time temperatures of up to about 16 °C is also characteristic of the local

climate. In the context of the urban configuration and climate of the “Shahre

Javan Community” site, the following findings regarding energy-efficient

aspects are outlined:

The linear arrangement of the existing housing typologies in Hasht-

gerd New Town and the maximization of south-oriented façades is a good

approach for the use of passive solar energy. The need for privacy however

contradicts the need for opening up the façades, and the greater consump-

tion of land demanded by such typologies conflicts with energy objectives on

an urban scale. Furthermore, the high demand for cooling energy in summer

needs to be considered in the architectural design.

The compactness of traditional courtyard housing schemes in dense ur-

ban layouts avoids energy loss for heating and cooling via the thermal enve-

The courtyard houses in Iran are traditionally located in arid and

semi-arid regions. The compact urban form of courtyard houses guarantees

good climate conditions inside the buildings. Only selected rooms and spaces

are oriented to the sun. The use of these areas depends on the heat impact of

the sun. Special (often temporary) functions make use of the solar heat input

in winter. The compact, almost closed volumes, ensure a more constant mi-

cro-climate in contrast to the considerable daily and seasonal fluctuations

on the macro-level outside.

To improve the micro-climate in high density areas, traditional ele-

ments, such as air circulation by making use of vertical shafts or shady court-

yards with plants or water basins, can be used as vernacular low tech devices

for better energy efficiency.

Introverted house East-west orientated house South orientated house

Fig. 4: Housing typologies and energy efficiency

lope. The shaded courtyards and their micro-climates produce thermal com-

fort and air circulation according to the building morphology. The solar heat

gain in winter periods is restricted to south oriented subzones. The introver-

sion of this typology respects the demand for privacy.

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

2 Research methodology:

a research by design process

The chosen research methodology for the Energy-Efficient-Homes is performed

for a residential pilot project in the “Shahre Javan Community” area in Hashtgerd

New Town. To ensure the appropriateness to the pilot project, the methods of re-

search are integrated in a planning process. The method suitable for combining

scientific and planning results is the research by design process. In a systematic

work process, the findings of a general approach and specific design allow for

the evaluation and definition of further steps. By applying this scenario-specific

methodology for architectural and urban design suppositions, that have been ob-

tained from a general approach, to real planning situations, the assessment can

be performed on different scales. Finally, the results gathered in the design pro-

cess are used to revise the formulation of the initial approach.

The data collection process and the analysis of preconditions for the task

“energy-efficient housing” is characterized by general dimensions (e. g. gener-

al aspects for energy efficiency and volumetric matters) and specific dimen-

sions (e. g. site and socio-cultural context). The influence of general and spe-

cific aspects enables the transferability of the results to a general dimension

(e. g. energy efficiency through spatial design) and a specific dimension (e. g.

climate and social adaptation). The graphic shows the research by design pro-

cess with the design and examination steps in a linear arrangement. The fi-

nal step shows the conceptual design for one urban unit in the pilot area as a

standard definition and design solution for application in the “Shahre Javan

Community” context (see Fig. 5).

2.1 Energy-Efficient-Homes in the “Shahre Javan Community” –

parameters of influence

The development of housing design solutions is affected by several groups of

parameters: spatial, social, economic and technical.

The different groups of parameters function as tools for the assessment.

The influential degree of each parameter group on the final design solution is

the result of their consideration, discussion and integration in the design pro-

cess. Several parameters can influence different groups (for example orienta-

tion as an aspect of urban design as well as energy efficiency). This highlights

the complex relations and influences amongst the groups. They should never

be seen isolated. Thus, the design for the architecture of housing typologies is

the result of an integrated planning process.

Following the approach that every architectural design is part of an urban

configuration, the influences of general dimensions on the architectural de-

sign solutions has to be proved by specific site characteristics and conditions.

The discussed requirements for the Energy-Efficient-Homes in the “Shahre

Javan Community” have led to the following parameter groups:

Urban design

The first group of parameters describes the influence of the urban design:

In continuation of the urban design criteria established in the project pre-

phase, the typologies must follow the urban morphology. The architecture of

housing typologies is directly influenced by the determination of urban design

features with a technological and socio-cultural background. The “hard facts”,

such as the access system, the technical infrastructure, the plot orientation and

the design requirements to avoid earthquake hazards are preconditions for the

site. The so called “soft facts”, such as identity, flexibility or the implementa-

tion of mixed-use schemes, should be integrated in the development of housing

typologies and are defined by the spatial measures of architectural and urban

design. They establish the ‘sensuous’ dimension of architecture.

Users and codes

The second group is characterized by the analysis of users and stakeholders.

It determines the requirements in a technical and spatial dimension. Building

codes, technical principles, materials, the demand for energy efficiency, as well

as local and regional specifications and urban design preconditions are anal-

ysed in an integrative process with the project partners.

The analysis of users, in the sense of a target group, helps to define the

technical requirements in a socio-economic context and encourages the im-

age and marketing strategies of the design.

Energy efficiency

The third group defines aspects of energy efficiency. Several aspects can be

derived from the urban design, like the orientation of volumes or technical ba-

sics, which again define the strategy on a building scale. Following the need for

energy efficiency, aspects such as the surface-to-volume ratio and the floor-or-

ganization influence the building design directly. The technical standard of en-

ergy efficiency (‘high tech standard’ or ‘low cost standard’ as possible bench-

marks) depends on the preconditions of the local and regional situation.

Sense of place and vernacular architecture

The fourth dimension is developed according to the research on vernacular ar-

chitecture and urban design. It shows the socio-cultural dimension of archi-

tecture. Traditional Iranian urban and housing designs support the building

typology following energy-efficient urban design criteria. The understanding

and use of space from public to private areas and vice versa influences tradi-

tional Iranian cities. The compact form is one approach for the creation of en-

ergy-efficient housing typologies and an identity of space.

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

Input from analysis Parameter

Urban design

Users and codes

Energy efficiency

Sense of place

Design approach

Criteria

Definition

of access system and urban

morphology

Adaption

to site and topography

Ground Floor

with mixed-use potential

Spatial hierarchy

from public to private

Potentials

multi-floor courtyard house

Orientation

Of volumes and surfaces

Application

Of simple constructions

Energy Efficiency

as a result the architectural

design

Architectural concept

as an expression of identity

Design concept Design measures

Orientation + dimension

.. Optimize sun orientation

through sculptural modelling

.. Possible vertical organization

of units in building volumes

.. Closed coverage in an east/

west direction

.. Façade openings to exterior

space in N and S

Organization + structure

.. Modular space system as

structural pre-condition for

functional and constructive

organization

.. Vertical continuity for

provision of economic and

simple construction methods

Access + vertical

connection

.. Entrance from path

.. Provision of additional

entrance from garage

.. Provision of central stairway

inside the volume

From public to private

.. Potential commercial unit

and entrance hall on ground

level accessed from path

.. Semi private stairway

.. Graduation of privacy inside

unit through organization

around courtyard

Variety + flexibility

.. Horizontal organization for

small units

.. Vertical organization for

big units

.. Morphological variety

through sculptural modelling

of upper floors

Fig. 5: Design process of Energy-Efficient-Homes

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

Design study

sub-neighbourhood

Adaptive measures

Site adaptation

.. Choice of type

.. Morphological variety

through plot layout and

dimension

.. Morphological variety

through sculptural mod-

elling of building volume

based on modular space

structure

Functional adaptation

.. Choice of type

.. Access system

.. Use (mixed use/housing)

.. Vertical or horizontal floor

organization

.. Variety of floor plan layout

Standard adaptation

.. Choice of type

.. Construction and materials

.. Facade structure and design

.. Energy efficiency

.. Supporting systems

.. Interior arrangement and

equipment

Energetic adaptation

.. Choice of energy system

.. Supportive, energy-efficient

measures on an urban scale

.. Supportive, energy-efficient

measures on a building scale

.. Construction and materials

.. Technological input

Typological

catalogue and

design scenarios

Innovations

Basic principle

Courtyard house

Resource protection through

building configuration

Modular space

Cost and energy – efficiency

through planning process

Upgrades

Sun shutters

Energy impact regulation

through facade elements

Light shelves

Energy gain through indi-

vidual natural light and heat

control

Photovoltaic fabric

Energy gain through individ-

ual control of natural light

and heat

Geothermal energy and heat

exchangers

Energy reduction through

air-driven, combined heat-

ing-cooling-ventilation system

Design for urban

unit

Conceptual design

Urban unit

Architectural plans

.. Site adaptation to techno-

logical, functional and

economical context

.. Spatial organization of

urban unit according to

basic principle

.. Spatial integration of

innovative upgrades

.. Spatial organization of floor

plans and apartment layouts

.. Preliminary plans concern-

ing construction and ma-

terials

.. Preliminary plans concern-

ing construction and ma-

terials

.. Visualization of spatial and

physical qualities

.. Integration of energy effi-

ciency concept on an urban

and building scale

Perspectives

.. Basis for tendering and

execution planning

.. Basis for construction and

detail research

.. Basis for adaptation to other

sites in the Shahre Javan

community

.. Basis for mitigation in a

regional context

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

3 Design strategy – analysis

and design approach

The analysis of preconditions and the definition of requirements determine

the influential framework of architecture. A certain vagueness in the formu-

lation (e. g. target group) can be replaced by assumptions or as a safeguard for

flexibility. Because this development of housing typologies is bound to the

application on the ”Shahre Javan Community” site in Hashtgerd New Town,

a “research by design” strategy was chosen for this specific scheme. In a first

step, the morphological and functional demands, as a result of the research

on energy efficiency and the urban design framework, were analysed and

transferred into a design strategy.

The strategy represents the aim of combining the advantages of two

main topics relevant for the energy efficiency in architecture and urban de-

sign: orientation and compactness. In a second step, strategies and measures

for energy-efficient housing typologies specific to the site conditions were

determined by adjusting the morphological study with the gathered groups

of parameters. The identified criteria were put into a catalogue as a tool for

the evaluation, adaptation and transferability of the site-specific design.

Fig. 6: Model study of energy-

efficient housing in a compact

urban form

Fig. 7: Approach for energy-efficient housing in a

compact urban form

3.1 Energy-efficient housing for a compact urban form

In order to ensure the ideal amount of sunlight in a horizontally organized

apartment building, the distance between the urban volumes has to be en-

larged. This however limits the density in a low-rise area.

Compactness, as the second most important factor for energy-efficient

architecture and urban design, provides thermal comfort inside the build-

ing, but limits the use of passive solar energy due to the orientation of the

volumes (Schramm, 2005, p. 79 ff).

The volumes in the compact urban design scheme have to take advantage

of their individual positions. The orientation is defined by access systems

and plot design – parameters which are determined by the urban layout. A

plot design with a north-south direction offers south-oriented buildings at-

tached at the western and eastern sides of the plot. This volumetric organiza-

tion guarantees south orientation for every plot, in particular if the compact-

ness is maintained and the façade surfaces facing east and west are reduced.

To gain greater width in the south façade, “supplementary south-fac-

ing surfaces” can be produced by shaping the volume with courtyards and

niches.

In addition, due to the vertical organization of dwellings with duplex or

maisonette typologies, the floor organization can follow the demand of sun-

light exposure. Rooms in need of direct sunlight, like major living areas, can

be organized on the upper level and behind the “supplementary south-facing

surfaces” in rear zones of the building volume. Sleeping or service areas need

less direct sunlight and can therefore be arranged in darker zones.

This strategy makes use of both advantages, the energy savings achieved

by reducing the cooling and heating loads through the compact form and

the energy gains through solar energy input achieved by the supplementary

south-oriented façades (Brunner et al., 2009, p. 42 ff). Seen economically, the

façade surface can be reduced by up to 30 % by attaching compact building

forms as described above. The result of this study can be seen as a contem-

porary and economic approach to vertically organized courtyard housing.

3.2 Criteria for energy-efficient architecture in the region

A criteria catalogue was compiled by analysing the parameter groups with

regard to their morphological consequences. This catalogue helps to identify

planning aspects for future evaluation, transferability and adaptation of the

typological study. The criteria function as important indicators (tools) and,

in total, as a task catalogue for design solutions.

3.2.1 Building criteria – strategy for designing housing typologies in the

“Shahre Javan Community”

The combination and discussion of the aspects formulated by the parameter

groups define the task of designing housing typologies for the “Shahre Javan

Community”. The result is a catalogue of ‘building criteria’ that describes

a design strategy for energy-efficient architecture and the urban design of

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

mass housing in a regional context. The criteria are named as follows:

Definition of access system and urban morphology

The typology must follow the urban design criteria. The process of designing

the typology perpetuates the findings of the urban design and raises it to a

more detailed level in terms of functionality and identity.

Adaptation to site and topography

The typology is adaptable regarding plot layout and topographical specifi-

cations.

Ground floor with mixed-use potential

As a provision for flexible use, the ground floor offers potential for different

commercial functions with housing on the levels above.

Spatial hierarchy from public to private

This is the definition of a functional spatial design in a socio-cultural con-

text. Design quality and its local acceptance is achieved through the adapta-

tion of regional customs and traditions.

Potentials of multi-floor courtyard houses

Introversion as an expression of privacy and climate-friendly organization of

volumes with regard to light exposure and quality of life.

Orientation of volumes and surfaces

Climate adaptation/optimization by adjusting building surfaces through ar-

chitectural design (e. g. supplementary south-facing elements).

Application of simple constructions

Economic and ecological building constructions in consideration of the re-

gional technological conditions. Design as a step towards efficiency.

Energy efficiency as result of the architectural design

Design as a strategy for energy efficiency. An integrated design approach in-

stead of isolated technological optimization.

Architectural concept as an expression of identity

The architectural design in the urban context of the ‘low rise – high density’

scheme creates a spatial identity for energy efficiency in the region.

4 Design solutions

Reflecting the criteria for energy-efficient housing in the context of its appli-

cation in the “Shahre Javan Community” led to different design scenarios for

a specific site in a variety of stages and scales. The conceptual scale allowed

for a study within a specific framework. The basis for the study was the de-

velopment of a typological approach using the criteria catalogue. Through

a modular space concept, typological characteristics of the approach were

Fig. 8: Private courtyard in an Energy-Efficient-Home

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

defined in terms of access, floor organization, constructive principles and

urban implementation. The outcome of the modular space concept describes

three basic types with a range and variety of dwelling sizes and different

housing styles as a first adaptive measure. The results of the concept were

monitored in models and sketches; studies and simulations were carried out

to determine the energy efficiency achieved using systems specifically cho-

sen to suit the local climate. The application to a specific site on an urban

scale in the pilot area gave a first impression of the concept’s potential to

vary the typology. The conceptual design of one urban unit in the “Shahre

Javan Community” is used to refine the design scenario in several revision-

ary steps and serves as a planning basis for a specific application with the

prospect of dissemination through energy-relevant elements.

4.1 The classification of types

The typological approach in architecture is characterized by the classifica-

tion of a hierarchical system of basic modules, their variations in arrange-

ment and adaptation to the site. The development of the building typology

starts with the adjustment of the gathered building criteria as the scientific,

theoretical and urban framework for the site specifications of the pilot area,

which is then used as a practical and physical basis.

Fig. 9: Modular space concept of the Energy-Efficient-Homes

The chosen scenario allows for the classification using a work process.

Integrated in the urban design concept, the first step of the typological ap-

proach is carried out as a parallel process with an analytical (top down) and

synthetic (bottom up) classification.

Beginning with the definition of types in an urban context, the analyti-

cal framework is provided by the site specifications and the demands for the

“energy-efficient housing in a compact urban form” (see 3.1). The developed

structure in the first draft of three housing types expresses the typological

approach. Due to the fact that the typology is adaptable to the length of the

site as a consequence of the urban design and the method of construction,

the classification is characterized by the width of the plot (7.5, 9 and 15 m

types). A modular space system, developed for introverted housing schemes

in a compact format, is the tool used for this adaptation process. By orga-

nizing and arranging spatial modules according to the depth of the site and

maintaining standardized widths, various floor layouts, sizes and designs

are possible.

The transfer of the carved-out types to the “Shahre Javan Com mu nity”

project on an urban scale and in a defined urban unit of the sub-neighbour-

hood highlights the potentials for adaptation of this typology, as is shown

exemplarily in the second step of the typological development. The results

gathered from this design scenario are then used to establish a typological

classification. In order to evaluate the potentials of modifications and vari-

ations of the building types within the typological concept and according to

the site conditions, the functional aspects, technical standards and adaptive

characteristics must be filtered out. In a third step, the characteristics are

defined and depicted in design studies and different scales. A catalogue of

possible variations of these basic types shows the morphological variations

and their urban relevance. The variety offered in the typological catalogue

can be regarded as a tool to create identity on a building and urban scale and

is an expression for the correlation between architecture and urban design.

The display of exemplarily variations on a building scale, in terms of floor

plans, sections and elevations, is therefore designed to evaluate the architec-

tural qualities. By illustrating the strategies and measures of constructional

concepts and elements for upgrading the energy efficiency through additive

technical equipment, a categorisation of standards can be achieved for the

identification of basic principles and additive upgrades. Thanks to this cat-

egorisation, measures and strategies for energy as well as economic alter-

ations are easily identified.

The main components of the typological design process are as follows:

Orientation and dimension

The urban design led to plots on the site of the “Shahre Javan Community”

with lengths of around 25–35 m, mostly with north-south orientations. Cut-

outs and courtyards are applied to the volume to increase the length of

south-oriented façade to generate greater solar yield. These structural inci-

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

sions create private locations and improve the climate conditions. A vertical

arrangement of setbacks produces further differentiation and enables direct

sunlight to reach into every dwelling unit.

Organization and structure

A structural system forms the basis of the layout strategy. A modular space

system with room axes for different room sizes is the structural basis for con-

struction and use. With its vertical continuity and the low building height,

with a maximum of three storeys, the structure can be organized with a sim-

ple system of walls and ceiling slabs or as a frame structure. The vertical

continuity even offers the opportunity to provide underground parking. The

structured volume facilitates a high variety of floor layouts.

Access and vertical connection

The house is accessed at street level and, in addition, by an entrance from

the underground parking. A hallway leads to the central stairway. Besides its

purpose of access and level connection, the stairway can also function as a

vertical air shaft. In smaller types with up to two dwelling units, the central

stairway can be replaced by interior private stairs.

From public to private

On the ground floor, the area facing onto the street is a potential commercial

unit. Together with the apartment above, it is possible to establish a mixed-

use scheme. The ground level functions as the first threshold from the public

area of the urban space into the private housing zone, with the commercial

unit and the entrance hallway as a semi-private entity. The stairway marks

the transition point from the semi-privacy of the interior access zone to the

privacy of each apartment. The vertical organization of apartments around a

central courtyard again creates different degrees of privacy affecting the in-

terior space. Areas for guests, service zones (kitchen, bathrooms, inner stair-

ways, etc.) and private family space can be organized individually due to the

flexibility of the structure.

Variety and flexibility

The structural system and the morphological concept permit a variety of lay-

outs; the morphological adaptation allows for different size dwelling units.

The vertical continuity of structural and technical elements also enables a

vertical connection of space (e. g. duplex units). The inner organization of

the units is regulated by a few structural elements (e. g. party walls on the

long sides of the building and staircases). The distribution and use of rooms

is therefore very flexible. A sloped location can offer greater dwelling areas

due to additional façades.

4.2 Scenario and transfer – the adaptive typology

The scenario work for the “Shahre Javan” site reviews and evaluates the

project aims and design results. The evaluation of the planning results for a

specific application helps to revise the developed concept. The detail plan-

ning for the “Shahre Javan” site (‘Tarh-e-Tafsili’ – see also Young Cities

Research Paper Series, Vol. 3) ascertains the potential for changes and

improvements of the housing typologies as a necessary part of each plan-

ning process. The conceptual design, as a basis for the execution planning,

defines the final design solution for one urban unit in the “Shahre Javan

Community”.

O R

O RR

Court-

yard

Court-

yard

Living Service Entrance Access

Entrance Service LivingAccess

private public private

Structure

Privacy

Modules

Orientation

Fig. 10: Structure of the Energy-Efficient-Homes

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

Re-transferring the first scenario to the general typological concept

shows the potential of the architectural design approach and enables a mor-

phological study of all basic types. Moreover, it highlights that the large

number of variations can function as an adaptive tool. This large variety on a

conceptual scale illustrates the potential for flexibility, especially in regard

of functional and technical adaptations, as well as the integration of identity

aspects. The consequences of a step-up in scale and an exemplary adaptation

of a specific type are revealed in floor plans and sections. The identification

of characteristics and the definition of measures for possible alterations are

the result of this work process.

4.2.1 Fixed and flexible elements

Elements and components with their technical, constructional and sensuous

characteristics ensure structure and functionality and are the basis of the

Energy-Efficient-Homes. They can be termed as flexible or fixed elements.

Modifications or adjustments to the volume and floor layout allow for

adaptation and transferability and are necessary to achieve variety and iden-

tity. While modifications and adjustments to meet the demands of specific

sites and functions are an adaption to the so-called “fixed” characteristics,

flexibility in the typology is required in the planning process. Concerning

the typology in the “Shahre Javan Community” area, the following charac-

teristics are representative and significant:

The modular space system serves as a framework for the construction

and organization of the dwelling units (fixed). On the other hand, the mod-

ular framework enables the organization of private zones and service zones

in different floor layouts (flexible). The vertical continuity of the structure

offers constructional and technical functionalities (fixed). The arrangement

of space modules to form different building morphologies on different plot

sizes is necessary to meet the functionality, privacy and energy efficiency in

a specific urban context (flexible).

Flexibility, meaning temporarily adaptable, is only provided by mea-

sures for façade design. For example, a certain combination of fixed and flex-

ible construction elements has a direct impact on light and energy efficiency

as well as the degree of privacy. It is achieved by the fixed structures in the

façade and the flexible regulation of mechanical shading elements. Due to

the fact that flexible elements have higher requirements in terms of techni-

cal details, they also have a direct impact on building costs. Thus their appli-

cation should be considered carefully.

Identifying fixed and flexible elements allows the formulation of adap-

tive strategies for the transfer of research and planning results as well as the

specification of elements to create architectural and urban identity and vari-

ety. The strategies for adaptation are classified according to different aspects

of the architectural design:

.. Morphology – as a volumetric feature to perform adaptations in an urban

context

.. Floor layout – for a functional and spatial adaptation within a single building

.. Passive and active energy measures – spatial and technical design features

for the adaptation of energy consumption

.. Appearance and construction – design and structural measures for the

adaptation of social and economic standards

4.2.1.1 Morphology – strategy for site adaptation

The design approach of the housing typology respects the urban design

concept as a spatial denominator for the insertion of a building. Thus every

building is a specific element in a larger spatial arrangement.

Due to this commitment, the design concept of the building must of-

fer suitable adaptive tools. Regarding the site, the developed modular space

scheme is adaptable by performing morphological measures.

The length of the building is the first adaptive measure. In a sequence of

modules, the length of the building can always respond to the plot size.

Depending on the length of the plot, in smaller vertical-organized hous-

ing types (7.5–9 m), the private courtyard is enclosed on three sides by pri-

vate rooms (in longer units) or only on two sides (in shorter units – north,

east or west), simply by adding or removing a space module.

For bigger housing types (12–15 m or more) and on longer plots, a second

courtyard is integrated in the building volume; on smaller plots, it is only one

courtyard.

Fig. 11: Typological catalogue

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

The second measure is the orientation of the volume. In order to achieve

variations in the orientation, improve energy efficiency and/or the degree of

privacy, the upper storeys in vertically-organized units can be modified. By

arranging the volumes, adding terraces or varying the layouts of the upper

levels, it is possible to regulate the incidence of sunlight and privacy. These

measures have a direct influence on the urban appearance and can also be

seen as a tool for creating identity.

4.2.1.2 Floor layouts – strategy for functional adaptation

For functional reasons, the housing typology must offer flexibility in its use.

On the one hand, this flexibility is necessary to meet the different needs

of users, on the other hand, the changing requirements in terms of target

groups or the insertion of commercial units for a mixed-use scheme de-

mand flexible floor layouts. A graduation of flexibility must therefore be de-

fined. It is not the aim of the architectural concept to create a fully flexi-

ble space, which is only fixed by the building envelope, even if the modular

space system were able to fulfil such a demand. The structural requirements

to achieve such a high degree of flexibility are more suitable for frequently

changing floor layouts as is the case in office buildings. It is more important,

in this case, to keep open the choice of construction method (from tradition-

al solid construction to pre-fabricated building elements) with space mod-

ule dimensions, which allow for a certain number of variations. In order to

maintain this flexibility, the arrangement of the spatial modules offer differ-

ent room as well as unit layouts and various fittings. Experience has shown

that most of the layout determinations are made in the planning phases be-

fore construction. Thus, the focus on flexibility is determined by the follow-

ing measures:

Fig. 12: Section through a 9 m–type building with two dwelling units, each with

its own private courtyard

The smaller types (7.5–9 m) provide two vertically organized dwelling

units with separate access at ground floor level. The staircases can be set

inside the private units with a first emergency exit via the entrance hall

and a second one via the apertures in the façades. As the demand for pri-

vacy is not easy to fulfil at ground floor level, because of the visibility from

the public streets, a mixed-use scheme with a commercial unit might be the

right the solution. Here a joint staircase for the units above is necessary as

part of the modular space scheme. The maximum number of dwellings in

these types could be four. The commercial unit can be planned as part of

the apartment above or as an independent space.

Private Living

Space

Guest

Space

Service Space

Kitchen

Corridor

Guest

Bath

Stair

Courtyard

Private Living

Space

Public Stair

Optional

private Entrance Private Terrace

Private

Bath

Private Terrace

Entrance Private Bath

Storrage

Private Living

or Work Space

Private Living

Space

Guest

Space

Service Space

Kitchen

Corridor

Entrance Guest

Bath

Private Stair

Public Stair

Courtyard

Private Living

Space

Ground floor 1st floor 2nd floor

Fig. 13: Floor plans of a two and three-storey dwelling in a 9 m-type with a

private courtyard and zoning inside the dwelling

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

For the bigger types (12–15m or more), the size and number of dwell-

ing units depend on the chosen floor layout. The combination of levels to

form vertical units is also possible within this typology. In buildings with

single-floor apartments, the number of units that can be arranged around

one courtyard ranges from one to two, and a maximum of eleven units in

total in one building. A joint staircase is always necessary in this case. In all

types, the size of the staircase must allow for the incorporation of an eleva-

tor to provide barrier-free access. Depending on the position of water and

energy supplies, different room layouts, such as closed or open kitchens, are

possible.

All in all, the organization of floor layouts is flexible enough to accommo-

date individual needs in terms of a unit. Furthermore, the flexibility of unit

sizes and layouts is a suitable tool to meet demands on the housing market.

4.2.1.3 Passive and active energy measures – strategy for energy- related

adaptation

Besides achieving energy efficiency through the building’s configuration,

further improvements can be made by performing additional measures.

Renewable resources, such as sunlight and ground temperature, can be used

by carrying out simple constructions.

Sunlight incidence and its effect on the energy demand

The amount of daylight use influences directly the demand for electricity

to provide artificial lighting. In the case of unfavourable light incidence or

angles, daylight can be redirected by using reflecting devices. The light di-

version can be used as a protection against too much light exposure or for

increasing daylight incidence, for example in deep rooms. In both cases, the

light diversion reduces energy consumption. On the one hand, it reduces the

Fig. 14: Light shelves (louvres) – summer position

cooling energy demand as it prevents overheating in summer; on the oth-

er hand, the reduction of artificial lighting reduces energy consumption di-

rectly. The provision of daylight depends on various factors, for example the

degree of sun exposure, the angle of incidence, the general layout, the num-

ber and dimension of transparent openings, the glass type and factor of light

transmission as well as the position of openings.

Light-diverting devices are available for internal and external use.

External devices are the most effective. Daylight is redirected into the room

by using, for example, external reflectors, mirrors or prism plates, which are

normally used for sun shading, but are very effective for diverting light. The

downside of external devices can be, depending on the form and position,

the dirt accumulation on devices, which reduces the efficiency and results in

higher maintenance than that required for internal light diverting devices.

In the “Shahre Javan Community” project, the configuration and com-

pactness of the buildings is responsible for reducing heat loss in winter and

avoiding overheating in summer. Furthermore, the north-south orientation

captures the intense radiation from the south and avoids the more critical east

and west sun in summer, which is more complicated to control.

Duplex units, which are positioned back to back, form a deep north-

south oriented housing complex. Inner courtyards with large south-orient-

ed openings help to provide an even amount of light throughout the apart-

ment. The ratio of street width to building height and the dimensions of the

inner courtyards optimize the relation between maximum illumination of

the rooms and negative impact of heat during summer (Nytsch-Geusen et

al., 2012).

In winter, the same light shelves in a vertical position receive approx-

imately 50 % of the sun and divert it into the north-facing rooms adjoining

the courtyard. This means that the rooms opening up towards the courtyard

Fig. 15: Light shelves (louvres) – winter position

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

are all lit and preheated by the sun. The above-mentioned downside of high-

er maintenance is negligible due to the overall dimensions of the courtyards

and the reachable position of the shelves, which means that the maintenance

can be carried out by the inhabitants.

As an alternative to the large rotatable shelves stretching across the court-

yard, a sun screen made of photovoltaic fabric can cover the courtyard in sum-

mer. It prevents the inner courtyard and adjacent rooms from overheating and

produces energy. In the evening, this energy can be used to partially illumi-

nate the same area. In winter, the fabric is pushed aside and the sun can warm

and lighten up the inner courtyard and adjoining rooms.

Heat-exchange to reduce the energy demand for heating/cooling

Currently most Iranian households use evaporative cooling systems in sum-

mer. For an apartment of 120 m2 with a room height of 2.8 m, an air-exchange

rate of 25 l/h is required to keep the temperature within a comfortable range.

This leads to an energy demand of 2.920 kWh of electricity and 63.5 m3 of wa-

ter per cooling season (Nytsch-Geusen et al., 2012).

Considering the high air exchange rate and the fact that the exhaust air

is still much cooler than the supply/outside air, it is obvious that the tem-

Fig. 16: Earth tube system in an urban unit

perature difference between the exhaust air and supply air should be used

to precondition the supply air. Preconditioning the supply air with exhaust

air works both in summer and winter. In summer warm/hot supply air is

cooled with the cooler exhaust air and in winter, when the exhaust air is

much warmer than the supply air, it is used to preheat the outside air and re-

duce the energy demand for heating.

This preconditioning of supply air can be achieved by installing a heat

exchanger. A heat exchanger relies on the fact that energy media want to be

in balance, which means that heat will dissipate and move to cooler materi-

als. A heat exchanger simply transfers heat (energy) from one medium to an-

other. The use of a heat exchanger enables the recovery of otherwise “lost”

energy contained in the exhaust air.

The described heat exchanger for use in a building/apartment can be in-

tegrated into the ground as an earth tube to supply a whole neighbourhood

with preconditioned air. The constant ground temperature at a depth of ap-

proximately 1.5–4 m below the surface is used to precondition the supply/

outside air.

A central supply air intake can be installed for several buildings and

dwelling units. The fresh air is drawn in through earth tubes that run in

loops and is either heated or cooled by geothermal energy through direct

contact with the soil. At a length of 50 m and a depth of 2 m the supply air

can be heated or cooled by at least 5 °C. This is a rough estimation for the

Hashtgerd region and its climate conditions, as no simulations were carried

Fresh outdoor air is preheated trough soil temperature

Preheated/-cooled supply air (+/– 5 °C)

Centralized fresh air intake

Supply air

Extraction

Fig. 17: Building section with heat recovery system

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

out during the project. However, the assumption is based on detailed stud-

ies for different regions and climate data, which has shown that the air tem-

perature can be lowered or raised by up to 10–11 °C depending on the specific

climate conditions (Blümel et al., 2001).

The combination of several dwelling units allows for a more economic

installation and use of earth tubes. For a sub-neighbourhood area, this could

involve a division into four zones. While the supply air intake is centralized,

the exhaust air system would be decentralized and work with a heat ex-

changer on a building scale as described above.

4.2.1.4 Appearance and construction - strategy for standard adaptation

and identity

Façade as a relevant element for energy impact and identity

Alongside the morphological arrangement (see above) as a strategy for creat-

ing an energy-efficient structure on an urban scale, the design of the façades

also has an influence on the appearance of a building. The structural meth-

od, the floor layouts and shapes as well as the architectural design of the

apertures characterize a building’s façades. The aperture typology is influ-

enced by role as energy impact element. Due to the fact that the south orien-

tation is important for the use of solar heat gain, the design of the apertures

within the façades is a very important tool for energy efficiency. Considering

the morphological arrangement of closed coverage and compactness, the

surface of the façades is initially reduced to a minimum. The south façades

of the single units, facing onto paths, courtyards and open areas, have to pro-

vide most of the sunlight for the living rooms. Therefore, the proportion of

apertures in south-facing exterior walls should be as high as possible.

Due to the high density of the “Shahre Javan Community” urban con-

cept, the positioning and dimensioning of openings must balance the need

for low energy consumption and privacy. The strategy used for balancing

and planning the façade design for the housing typology chosen is performed

on two levels. On the first level, the design of the façade is characterized by

the fixed elements of the building`s structural system, the construction of

Fig. 18: Study of different south façades for 7.5 m building type

the exterior walls and the zoning of closed and open elements. On the sec-

ond level, flexible elements to control light and sun incidence structure the

façade.

The dense configuration of the “Shahre Javan Community” pilot project

requires measures for privacy. As a first measure, the width of standard ap-

ertures with a higher privacy factor is reduced, but the proportion of glass is

maintained by choosing vertical, room-high apertures. A staggered arrange-

ment of apertures on opposite façades avoids direct views and is a second

measure to achieve privacy. From an economic point of view too, high, nar-

row openings with a simple mechanism are more reasonable than horizontal

ones.

Alongside the demand for good technical standards as a means to in-

crease the quality of the windows’ thermal insulation, the design of the aper-

tures is a tool for regulating sun incidence and a first opportunity to achieve

variety within the exterior appearance. Size, number and location of aper-

tures, however, depend on the façades structure. In order to maximize the

aperture surface, the window is no longer only an opening in a closed wall,

but a constructive element of the building envelope. A frame structure means

that façades are classified as non-load-bearing walls and there are greater

possibilities in regard of the arrangement and construction of elements. The

appearance of the façade is thus characterized by the layout of load-bearing

and non-load-bearing elements and by the design and positioning of the ap-

ertures within the closed walls (e. g. thermal insulation composite system).

Windows can, for example, be aligned with the outer or inner surface of the

external wall. Set into the wall, a small overhang is formed which already

reduces the heat load of the high sun in summer. This structural shading of

the frame is a “fixed” measure. On a second level, the individual control of

view and energy input is achieved with “flexible” measures. By installing

sun shutters or blinds on the outside of the façade, individual control is made

possible. Flexible, mechanical control of the elements regulates the energy

input during daytime, but also provides a means of controlling the amount of

privacy in the living areas.

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

Construction method – application of simple constructions

The modular space system of the building typology allows for a variety of

construction methods.

The room axes are the basis for construction and use, and define the

modular space system. As described earlier, the different plot types start

with a 6 meter axis-centre distance and can reach a width of 15m in 1.5m

steps in an east-west direction. This modular system offers a great variety

of floor layouts with the most economic structural span being of 7.5 m. The

depth of the building structure can be adapted according to the plot layout

by adding spatial modules in north and south direction. The terrace ends

with façades facing the open areas are set on the boundary lines. The chosen

modular system is based on an economic construction grid. With its vertical

continuity and the low building heights, featuring a maximum of three sto-

reys, the structural system is kept simple and a frame mode of construction is

possible. Pre-fabrication, in-situ construction methods or a combined solu-

tion with semi-precast elements are all possible and depend on site condi-

tions, traditional building methods/ education of workmanship, availability

of material and budget. The same applies to the range of possible construc-

tion materials. A frame construction made of concrete can be combined with

light wall materials or bricks. The difference in thermal behaviour at the in-

terface of the materials is evened out by installing a thermal insulation com-

posite system (ETICS). A monolithic system without exterior insulation in

combination with a concrete frame structure must be assessed regarding its

thermal properties. A system for a monolithic structure could involve shear

walls and concrete ceilings. The shear walls must be placed inside the unit as

the façade, in this case, only functions as a non-load-bearing thermal enve-

lope, for example using perlite or mineral wool-filled bricks or light concrete

blocks. Due to the special demands concerning earthquake resistance in the

region, the choice of the construction system and materials is very much de-

pendent on the site conditions. A concrete framework with concrete brac-

ing walls inside the units and ETICS as the thermal envelope was chosen as

the structural system for the Energy-Efficient-Homes in the Hashtgerd New

Town pilot project area. The choice of the remaining façade materials (e. g.

bricks) can be made according to ecological as well as economic aspects.

4.3 “Basic Principle” and “Upgrades”

The result of the design process for adaptive measures and the identification

of urban, architectural and technical elements for developing the Energy-

Efficient-Homes led to a distinction between a basic principle and possible up-

grades. This categorisation helps to define different standards as well as a sci-

entific basis for the planning process of energy-efficient housing in the region.

The basic principle is the design strategy for energy-efficient architec-

ture and urban design from a spatial approach without any additional tech-

nical demands. It contains all planning and design measures to increase en-

ergy efficiency through spatial configuration, such as building orientation

and compactness, site suitability and cultural context. It can be seen as a

low-cost approach and defines a minimum standard for energy efficiency in

the Middle East.

The upgrading measures include possibilities to raise the standard of

the basic principle. Supplementary technologies can be integrated into the

spatial approach. (see 4.2.1.3 and figures 14–17)

Possible upgrades include simple mechanical elements for light and en-

ergy guidance, such as sun-shutters, furthermore the use of the ground tem-

perature by means of earth tubes and a concept of heat exchangers, and fi-

nally the application of higher technological materials, such as photovoltaic

fabrics to generate supplementary energy. The measures are characterized

by a planning dimension as well as a technological and economic dimension.

The choice of upgrading measure is dependent on the economic and techno-

logical context. The upgrade defines the standard for maximum energy effi-

ciency in the region.

4.4 The conceptual design

The findings of the design and research process for the Energy-Efficient-

Homes are transferred to a final design proposal for an urban unit in the

“Shahre Javan Community” pilot project. By transforming the design and

adaptation measures from the typological approach into a specific design

scenario, the challenges for the practical application of such a general ap-

proach can be weighted and evaluated. Furthermore, the realistic scenario

serves as a basis for cost estimations, energy simulations and construction-

al detailing. Architectural models and drawings of the architecture in the

“Shahre Javan Community” to a scale of 1:100 to 1:20 are used to define a

standard for materials and energy objectives.

Fig. 19: Basic principle of Energy-Efficient-Homes

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

Fig. 20: Areal view of urban unit from the southeast

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

The chosen site in the centre of the pilot area (sub-neighbourhood 3.3)

is located on a ridge with access from the collecting road coming from the

eastern valley and bordered by the central public green of the western valley.

Following the determinations of the “Tarh-e-Tafsili” (Detailed Plan),

developed by the Strategic Dimension Urban Development and Design at TU

Berlin, the urban outline as well as the inner access routes are fixed by build-

ing lines. Parking is provided below the building development with access

from the collection road. The inner access paths are for pedestrians as well

as for supply and emergency traffic. The paths structure the urban unit into

four building sections. A small urban square, positioned at the crossing of the

access paths, is the social and spatial centre of the urban unit.

The density on the building plots was estimated using a floor area ratio

of about 1.7–2.0. The range in apartment sizes was set at 75-200 m² for at least

75 % of the dwelling units. A possible replacement of different housing types

creates flexibility. For example, to gain greater variety, the seven 7.5 m types

in the south-western section can be replaced by six 9 m types still staying

within the building lines.

4.4.1 The architectural design solution in an urban context

The conceptual design shows a specific design scenario for one urban unit

from the typological approach with adaptations to the site specifications us-

ing the described morphological strategies, the floor layouts, the energy-re-

lated measures and the choice of construction method.

The design of the urban unit should offer a large variety of dwelling

types. Alongside the single-floor apartments on broader plots, single family

housing is also provided. The suitable basic types determined in the topolog-

ical approach are the 15 m type for single-floor apartments and the 7.5m and

9m types for duplex units. For an effective infrastructure and a clear urban

identity, all buildings are accessed from the inner paths of the sub-neigh-

bourhood. By placing the parking level underneath the southern plots, the

site`s slope is exploited. A main exit from the parking level with stairs and a

lift is placed on the central square of each sub-neighbourhood.

The distribution of building types is aimed at maximizing direct sunlight.

The south orientation of the plots and the sloped topography ensure maxi-

mum passive solar heat gain in winter. The overheating of open spaces, such

as paths and courtyards, is avoided in summer by installing suitable shading

devices. Positioning three-storey apartment buildings on the northern plots

of each sub-neighbourhood and two-storey duplex units on the southern ones

enhances the use of passive solar energy in the northern buildings, which are

separated by narrow paths. The north-south directed green areas between the

sub-neighbourhoods are wider than the 6m-wide paths within the sub-neigh-

bourhoods. Thanks to the natural slope of the site, sunlight is never an issue

for the southern plots in the sub-neighbourhood. Terraces on the third floors

of the apartment buildings are designed to provide supplementary light to the

rear zones of the buildings as well as more differentiation in the façades.

The second measure to enhance light input is a partial set-back of some

of the duplex units on the southern plots. This has more than one advantage.

First of all, the partially enlarged paths can function as semi-public entrance

zones for the duplex units, secondly it allows the parking level to be natu-

rally ventilated and lit through apertures in the ground. Last but not least,

it improves the lighting conditions of the northern buildings. Thus the mor-

phological measures for greater efficiency ensure, at the same time, spatial

quality and low energy consumption.

4.4.2 Design solution for the residential buildings

The multi-storey apartment buildings are organized around a large central

courtyard. The central stairway with lift separates every floor into two units.

Setbacks on each level are used to generate at least one private terrace for

each dwelling unit. Every apartment has façades facing private zones (court-

yard) and public areas (path or open space). The main openings are always

oriented south. This solution considers the desired use of passive energy and

maximizes privacy by avoiding direct views between two opposite units.

Due to setbacks in the upper floors of the spatial modules, the courtyard

is enlarged and the apartment size changes. The apartment layout is divid-

Fig. 21: Detail section of the conceptual design

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

ed into private and public zones. The private bathroom and bedroom zone is

separated from the more public living and kitchen zone. Depending on the

size of the apartment, the distinction between private and public zones with-

in the apartment is solved differently. In large apartments, the public zone

includes a large entrance hall and a flexible space either for office use or as a

guest bedroom including a small bathroom. The kitchen block separates the

public zone from the private living zone with bedrooms and bathrooms set

in the rear of the apartment.

The units on the ground floor, facing the central square, are used as com-

mercial units and are therefore part of a mixed-use scheme.

The buildings with two duplex units, each facing south, are more intro-

verted. The two storeys of each unit are organized around a private court-

yard. Morphological measures in the courtyard arrangement, as described

earlier, enhance the use of passive energy. Due to setbacks on the upper lev-

el within the modular space system, the incidence of sunlight is maximized.

The north façade facing the private courtyard is also set back on the upper

level allowing more direct light to penetrate the south-facing façades. Like in

the multi-storey apartment buildings, the roof created by the set-back can be

used as a private terrace on the upper level, in the case of duplex units, this is

within the same unit. Thanks to this arrangement, even the rear zones with-

in the deep building volumes receive natural daylight. This has the effect that

the façades visible to the public require very few openings. The two units in

every building are organized in a back-to-back arrangement.

Following the hierarchy from public to private space, the semi-private

entrance courtyard (widening of path as described earlier) provides the first

step into privacy, at the interface of the urban and building design. The two-

unit building type is accessed from this zone. The subsequent hall and corri-

dor are a “dead end” in the sense of the traditional spatial hierarchy (see 1.2.1).

Within the private unit, the hall, with a central internal stairway, is part of

the vertical and horizontal arrangement. In apartments with two levels, it

is easy to make a distinction between private and guest/ public floor areas

(as shown in the floor plans of the dwelling units). With the public zones on

the lower level, the upper level ensures absolute privacy. If the private zones

are accommodated on the ground floor, guests are immediately guided up the

stairs without passing the private zones.

The floor plan layouts illustrate the relation between energy efficiency

and privacy. Although the arrangement of private zones at ground floor level

does not comply with Iranian traditions and culture, advantages in terms of

energy efficiency and privacy can be achieved.

Private bedrooms do not require as much light and heat as living zones.

The façades of private zones can be designed with a smaller proportion of

window surface. Transom windows deliver sufficient light at the same time

as avoiding views into the private rooms from the street.

The parking level is dependent on the construction of the buildings above.

Placed in an earthquake-prone area, the load-bearing elements have to be

continued down to the foundations. Shear walls and columns are organized

in the modular space arrangement. The main exit, with staircase and lift in

the urban square, guarantees central accessibility even for disabled persons.

Further stairs and the entrance/exit ramps serve as emergency exits. The

main lane is positioned beneath the access path. General facilities used by the

whole sub-neighbourhood, such as the grey water supply system and the en-

ergy plant, are located beneath the central square.

With the help of the typological approach, the conceptual design for the

Energy-Efficient-Homes illustrates the strategies for adaption on different

levels and scales.

4.4.3 Conclusion of the conceptual design

In accordance with the provisions of the detailed plan (Tarh-e-Tafsili) of

the “Shahre Javan Community”, adaption of the typological approach on

an urban scale is achieved in the conceptual design of the Energy-Efficient-

Homes by:

.. the choice of type and its position as a functional adaptation measure

.. shape and organization of the volumes, e. g. by implementing entrance

courtyards and setting back volumes, as a morphological adaptation mea-

sure.

Adaption on a building scale is achieved by:

.. the floor layout, such as the arrangement of private and public zones, the

cut-outs in upper levels for better light conditions in the courtyards, as a

morphological and functional adaptation measure.

The energy efficiency is enhanced on a detail scale by:

.. adapting the façade design to suit the site, e. g. by integrating sun shutters

.. provision of system-relevant elements, such as the technical plant

beneath the central square and the earth tubes at parking level

.. choice of materials with respect to site conditions, availability, required

standards, energy-related objectives and economic aspects, e. g. choice of

materials for the thermal envelope and construction system.

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

5 Perspectives

Fig. 22: Urban path in sub-neighbourhood

The research process in this design concept is aimed at providing a planning

concept for energy-efficient housing in the Iranian New Town programme

with a potential for dissemination and adaptation.

The spatial strategy, which considers the energy-relevant aspects of ur-

ban and architectural morphology within a specific social context, has led to

a concept of basic practical energy standards that are adapted to the region.

The courtyard housing scheme of the Energy-Efficient-Homes shows a new

development based on the origins of vernacular architecture.

By adding technical supply systems (e. g. light and sun directing ele-

Fig. 23: Urban square in sub-neighbourhood

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

ments or earth pipes to make use of geothermal energy), it is possible to up-

grade the energy efficiency already achieved by the basic standard through

spatial organization and design.

The volumetric arrangement incorporates socio-cultural references to

Iranian vernacular architecture. The urban and architectural design com-

bines the aims for energy efficiency and a regionally adapted identity by in-

tegrating spatial aspects into the socio-cultural context.

5.1 Potential for realization

The developed design solution for the Energy-Efficient-Homes is a concep-

tual guideline for the detailed planning of the “Shahre Javan Community”

pilot project. The typology needs to be examined carefully regarding the

chosen construction method (especially the earthquake resistance), site to-

pography and building quality standards (target groups). The gathered adap-

tive measures describe a future work process. These include, among others,

the choice of typology as a tool for controlling the size and number of units

as well as the choice of construction method and façade appearance as a tool

for economic issues and identity within the estate.

5.2 Potential for transferability in the region

Because of its high degree of variability concerning unit size and morpholog-

ical adaptation, the typology can serve as a basis for transferability to oth-

er sites in the region. The developed housing scheme, based on traditional

spatial arrangements, offers culturally adapted energy-efficient housing for

the Middle East. The energy-relevant advantages of the compact urban form

and its building configurations could change to provide higher spatial qual-

ity for new towns as the concentrated building volumes create clear defined

open spaces with public relevance. The simple basic layout and structure of

the introverted, individually controlled dwelling units also accounts for the

specific technical and economic conditions in the region.

Urban Design and Architecture

Authors

Prof. Elke Pahl-Weber | Philipp Wehage | Annette Wolpert

Date

November 2011

6 Architectural plans

Fig. 24 Site plan of the “Shahre Javan Community” with the urban unit marked

magenta (Sub-Neighbourhood 3.3)

commercial

unit

commercial unit

5 m 10 m 20 m

Fig. 25: Ground level floor plan

Fig. 26: First level floor plan 5 m 10 m 20 m

Fig. 27: Second level floor plan 5 m 10 m 20 m

energy plant

parking

water collection/distribution

Fig. 28: Basement floor plan 5 m 10 m 20 m

A–A

Fig. 29: Section and east elevation

B–B

Energy-Efficient-Homes – Designing Energy-Efficient Architecture in an Urban Context

7 References

Bianca, S.:

Hofhaus und Paradiesgarten. Architektur und Lebensformen

in der islamischen Welt. München: Beck, 1991.

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Erdreichwärmetauschern für Heiz- und Kühlanwendung, Gleisdorf, 2001.

Brunner, R., Hönger, C., Menti, U. Wieser, C.:

Das Klima als Entwurfsfaktor. Luzern: Quart, 2009

Diba, K.:

What Islamic Architecture Is Not; in: Petruccioli, A. et al.

Understanding Islamic Architecture. New York: Rutledge Curzon, 2002.

Edwards, B., Sibley, M., Hakmi, M., Land, P.:

Courtyard Housing. Past, Present and Future. Abingdon: Taylor & Francis,

2006

Hegger, M., Fuchs, M., Stark, T., Zeumer, M.:

Energie Atlas. Nachhaltige Architektur. Basel: Birkhäuser , 2008.

Nytsch-Geusen C., Huber J.:

Pilotprojekt 35 ha, Simulationsbericht Team 2, Version 1.4, Berlin 2012.

Schramm, H.:

Low Rise-High Density, Horizontale Verdichtungsformen im Wohnbau.

Wien: Springer, 2005.

Wirth, E.:

Die orientalische Stadt im islamischen Vorderasien und Nordafrika.

Städtische Bausubstanz und räumliche Ordnung, Wirtschaftsleben und

soziale Organization. Mainz: Von Zabern, 2000.

Wehage, P., Pahl-Weber, E.:

Architectural Studies in: Pahl-Weber, E., Seelig, S., Ohlenburg, H.: The

Shahre Javan Community Detailed Plan – Planning for Climate Responsive

and Sustainable Iranian Urban Quarter. Berlin: Young Cities Research

Paper Series, Vol. 3, 2012.

Preface .................. 3

1 Introduction ................ 4

2 Research methodology: a research by design process .....10

3 Design strategy – analysis and design approach ......16

4 Design solutions ...............19

5 Perspectives ................42

6 Architectural plans ..............45

7 References .................52

Table of Contents

Publisher

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Imprint

All texts are based on scientific research performed within the

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of the respective article’s authors, unless otherwise mentioned.

ISSN 2196-517X (Print)

ISSN 2196-6583 (Online)

ISBN 978-3-7983-2565-4 (Print)

ISBN 978-3-7983-2566-1 (Online)

Simultaneously published online on the Digital Repository

of the Technische Universität Berlin

URL http://opus.kobv.de/tuberlin/volltexte/2013/4022/

URN urn:nbn:de:kobv:83-opus-40225

[http://nbn-resolving.de/urn:nbn:de:kobv:83-opus-40225]

Design/Typesetting büro-d | Communication Design Berlin

German-Iranian Research Project

Young Cities

Developing Energy-Efficient Urban Fabric in the Tehran-Karaj Region

www.youngcities.org Energy-Efficient-

Homes

Designing Energy-

Efficient Architecture

in an Urban Context

Philipp Wehage, Annette Wolpert, Elke Pahl-Weber

Young Cities Research Briefs | 10

The volume before you results from the federal funded research

project “Young Cities – Developing Urban Energy Efficiency”.

It has been written by

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