Towards Better Urban Spaces in Harmony with Microclimate: Urban design and planning regulations in hot dry Damascus, Syria

Abstract

This research is an attempt to develop further understanding of the relationship between microclimate, thermal comfort, urban design and outdoor space users in the hot dry city of Damascus. This is done by studying the impact of urban regulations on microclimate in different urban design patterns in Damascus. This study also aims to investigate the behaviour of different thermal comfort indices and defines the thermal comfort limits for Damascus in the summer and winter seasons. In addition, understanding how to apply the knowledge of urban microclimate and thermal comfort in the urban design process is also a part of the aim.



The study analyzes and climatically examines the urban planning regulations through simulations. In addition, micrometeorological measurements and structured interviews in different urban environments are carried out in the summer and winter seasons. The study deals with attached (Old Damascus) and detached building geometries (modern Damascus). However, it focuses more on modern Damascus to develop the thermal environment in both existing and future urban spaces. By combining the results of measurements and structured interviews on people’s subjective thermal perception, the upper and lower thermal comfort limits for two thermal comfort indices – the physiologically equivalent temperature (PET) and the standard effective temperature for outdoors (OUT_SET*) – are defined for summer and winter respectively. Furthermore, a parametric study was carried out using the microclimate simulation programme ENVI-met. Modelling and simulations were conducted for summer and winter in order to study how to improve the outdoor thermal comfort in Damascus by investigating different urban design scenarios and using different landscape elements in simulations carried out during the different hours of the day. In order to investigate how the urban design in Damascus could be adapted to the microclimate and outdoor thermal comfort, an evaluation of an urban design proposal is done from a thermal comfort point of view through simulations where the thermal comfort limits are applied.



The study concludes that the existing planning regulations in Damascus have no requirements for shading for pedestrians, e.g. shading devices, arcades and projecting upper floors or shading trees. Apart from leading to poor microclimatic conditions in the summer, land use in the modern part of Damascus is highly inefficient, with a disproportionately large amount of ground occupied by streets, pavements and yards. In the case of urban canyons, the study confirms that the aspect ratio, street orientation, and vegetation are very important in street design. On the other hand, in urban environments consisting of detached buildings as in modern Damascus, the influence of street orientation and aspect ratio on surface temperatures and outdoor thermal comfort is less important, whereas the use of vegetation may reduce surface temperatures and improve the outdoor thermal comfort substantially.



For future urban residential areas in Damascus, it is therefore important to update the existing urban planning regulations according to the climatic requirements. This can be done by reducing front and side setbacks or to have none at all, planning narrower streets, increase the maximum number of floors permitted, and allowing projections of upper floors. Moreover, architectural design elements, which provide shade for pedestrians at street level such as balconies and arcades, ought to be used more. In addition, outdoor thermal comfort in existing urban areas in modern Damascus could be improved by introducing vegetation and landscaping in the urban design process. It is therefore important to create a link between landscape design and urban planning regulations. Such a link could be as a set of guidelines for street design and plant selection, i.e. choosing the right type of vegetation and using non-evergreen trees that can provide shade in the summer and help the solar radiation to reach the ground in the winter.

Abstract (Swedish)

Popular Abstract in English

This study concerns the city of Damascus in the Syrian Arab Republic. Damascus is a city where the current urban form is characterized by wide streets and lack of shade as well as limited amount of green areas, which negatively affect the microclimate and thermal comfort. This study is mainly focused on residential streets and how the urban planning regulations affect the street spaces as well as the spaces between buildings. The shape of the street influences the outdoor thermal comfort which in turn affects people’s human health and well-being.



In order to improve microclimate and increase the level of outdoor thermal comfort in future urban design in Damascus, it is important to develop the existing urban planning regulations according to the climatic requirements. This can be done by reducing the space between buildings, planning narrower streets, increase the maximum number of floors, and allowing projections of upper floors. Moreover, architectural design elements, which provide shade for pedestrians at street level such as balconies and arcades, could be more used. In existing urban areas in modern Damascus, outdoor thermal comfort could be improved by introducing vegetation and landscape elements in the urban design process.



This study highlights the importance of a climate-conscious urban design and design flexibility. Using urban design elements such as vegetation and shading devices (vertical and horizontal) can improve the level of thermal comfort. However, these elements can worsen the situation during the winter since they block the solar radiation to reach the area. Thus, this study encourages the use of flexible urban design elements, which can be regulated in every season according to climatic needs. Elements such as removable shading devices, flexible light skin roofs with light materials over streets and pavements are examples of flexible urban design elements that can be used in urban design for the hot dry climate of Damascus.



This research is an attempt to develop further understanding of the relationship between microclimate, thermal comfort, urban design and outdoor space users in the hot dry city of Damascus. This is done by studying the impact of urban regulations on microclimate in different urban design patterns. This study also aims to investigate the behaviour of different thermal comfort indices and defines the thermal comfort limits for Damascus in the summer and winter seasons. In addition, how to apply urban microclimate and thermal comfort in the urban design process is also a part of the aim.



To investigate different urban design patterns based on urban planning regulations, a microclimate simulation study was performed. Based on the simulation results, the thermal comfort was analyzed. In addition, micrometeorological measurements and structured interviews with the people in streets – in six locations during the summer and winter – were conducted to assess the microclimate of the outdoor urban environment and to investigate how people perceive the thermal environment in Damascus.



This study provides basic knowledge for architects, designers, and planners about the importance of microclimate and thermal comfort in urban design and planning. This study also provides useful insights in the field of microclimate and thermal comfort about how to mitigate the negative aspects of urban design on microclimate and comfort in hot dry climates. Based on such knowledge, better urban spaces can be created by taking microclimate and thermal comfort into account.

• author: Yahia, Moohammed Wasim
• supervisor: Johnny Åstrand
• opponent: Prof. Katzschner, Lutz, University of Kassel, Germany
• organization: Housing Development and Management (research group)
• publishing date: 2014
• type: Thesis
• publication status: published
• subject: Architecture
• keywords: Architecture, Arid zones, Built environment, Climate, Climatic design, Damascus, Hot dry regions, Landscape elements, Microclimate, Planning regulations, Thermal comfort, Thermal indices, Urban climate, Urban design, Urban planning
• pages: 222 pages
• defense location: Lecture Hall A:A, at the A-building, Sölvegatan 24, Lund University Faculty of Engineering
• defense date: 2014-06-13 09:00:00
• ISBN: 9187866-39-0
• ISBN: 978-91-87866-39-5
• language: English
• LU publication?: yes
• id: 90ff0d06-9bda-4558-9603-4fa9528af748 (old id 4438622)
• date added to LUP: 2016-04-01 14:11:45
• date last changed: 2023-11-14 15:48:25