Workshop: Architecture-Tradition and Modernization. Climate Responsive Urban Design

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1 Workshop: Architecture-Tradition and Modernization Climate Responsive Urban Design

2 Trends of none sustainable planning Planners of the twentieth Century seem to have assumed that urban settlements were supposed to be unsustainable. The results were cities that consume natural resources and produce waste and pollution with lack of green spaces and inefficient transport systems. The world reserves of fossil fuels are being depleted. pollution is causing irrecoverable damage to nature.

3 Towards sustainable planning It became necessary create trend towards sustainable settlements which are to be: Echo system focusing on harmony between buildings and the surrounding environment of Mother Nature. Conservation of both natural and built environment. Giving priority to the adaptation and re-use of recycled building materials and components. Minimizing the consumption of energy used in buildings and for travel between essential activities of the city. Giving priority to the adaptation and re-use of recycled building materials and components.

4 Why Energy-Efficient solutions Air-conditioned building in a Hot- climate regions consumes 70-80% energy. More energy is needed to cool than to heat. Within a few decades 60-70% of the total world population will live in urban areas. Energy prices will be increased. Alternative energy sources (e.g. solar power) should be introduced. Naturally occurring resources should be integrated into planning and to promote energy savings.

5 Passive and Active thermal design Passive climatic design Design solutions that exploit passive measures (e.g. building envelope design, climatic conditions and natural energy sources) to achieve the desired indoor and outdoor comfort conditions. Active climatic design Internal comfort is achieved primarily through mechanical measures. Combined Passive and Active Combination of passive design of building supported by limited mechanical equipments.

6 Modern movement-active thermal design In the past, buildings were constructed using passive measures Active design came with modern movement as means of satisfying comfort concerns in buildings. Thus modern architecture lost its connection to 'place'. Built environments are now totally controlled and divorced from their surroundings. Energy in getting depleted and it is becoming very expensive to maintain the modern totally controlled built environments.

7 Thinking passively -1 Passive measures rely on utilizing the elements inherent in a region's climate and its natural energy sources. To use passive measures is to accept the dynamics of nature. New habits must be introduced: This involves a dialogue with nature and reacting to the changes that occur with the seasons of the year and the time of day

8 Thinking passively -2 It requires an integrated approach. It involves all disciplines - urban planning, architecture, engineering, construction, etc. At all levels of the design process and through all details of a building. It includes operation and management of the buildings and the development of adaptation.

9 A sense of place: Working in Context -1 The climate and landscape inherent to a region has through time served as the foundation for the design of the urban and built environment. To design according to the characteristics present in nature leads to an architectural vocabulary that is shaped by rational, reasoned and proven solutions. It also produces a language that is accessible to all, and its inherent attractiveness is 'natural' owing to a harmony with its environment.

10 A sense of place: Working in Context -2 Traditional intimate city of the Middle East was replaced with wide streets, laid out in grids with rows of individual houses on individual plots of land Have often been based on imported Northern European models. They make no reference to their context and they use inappropriate building forms, materials and openings. They fail to provide protection from the fundamental cause of discomfort such as solar radiation.

11 Preconditions for Successful passive Design Introducing sustainable design ideas is not possible without full support from all parties involved. This involves the education of authorities, clients and designers, and a change in attitude towards energy conservation. Authorities should adopt urban planning principles and energyefficient design criteria. Codes in developing countries should be based on the local conditions each specific country and not on foreign standards. Clients and developers can be motivated by government initiatives with regulations and codes concerning energy consumption.

12 New approach in Passive design In active design the architect generally designs a building, and the engineer will afterwards try to adapt the building to its surrounding climatic conditions using mechanical air conditioning with little concern for energy consumption. In passive design close and intensive cooperation between architects and engineers. Passive design requires thermal evaluations of an architect's designs throughout the design process. Protection from climatic extremes through ecological planning and optimization of energy wind sheltering, natural cooling, ground water management, and vegetative buffer zones. Passive should influence the modern architecture form just like it did with traditional architecture.

13 The Problem Most modern settlements in Oman are made up of detached dispersed building blocks with wide grid streets with intensive transportation resulting in: High heat stress on summer days due to high solar radiation and ambient air temperature. High glare from direct and reflected sun light. Prevalence of dusty street winds. High cost of energy for the attainment of thermal comfort in buildings that did not interact with the requirements of the climatic environments. Problems of air, water, and noise pollution.

14 Climatic regions in Oman: Hot dry desert ( north west) Maritime desert ( Coastal) Upland desert (mountains)

15 The Climate of Muscat ( as an example) The Sultanate of Oman is situated between latitudes 16 and 26 N, and between longitudes 20 and 60 E. Muscat lies at the Tropic of Cancer at latitude 23.5 N, and longitude 58 E in an enclave of flat narrow coastal strip surrounded by high mountains and open to the sea. The large mountainous arid land mass creates a Maritime desert climate as shown below.

16 HOT MARITIME DESERT CLIMATE -1 Air temperature: Hot season: mean max:34-40 c mean min :24-30 c Cool season: mean max: c mean min : c Diurnal range: c Relative humidity: 50% - 90% Great evaporation from the sea Vapor however remains suspended in the air causing very uncomfortable conditions.

17 HOT MARITIME DESERT CLIMATE -2 Precipitation: Slight and variable throughout the year mm/ annum Sky Conditions: Normally clear dark blue and sometimes hazy due to the suspended water particles in the air Solar Radiation: Mostly direct and strong, but with strong diffuse due to hazy sky. Strong reflected component from ground and buildings causing glare. Long wave re-radiation from all heated surfaces is not as rapid as pure Hot-Arid regions causing temperature diurnal range being not very high.

18 Lessons from the vernacular architecture in Oman There is much to be learned from traditional Omani architecture in it interrelation with climatic environment. They have thousands of years of research of trial and error into the relationship between building and climate and represent models for the development of a climate responsive architecture. They created a regional architecture of the place, with the form and character generated out of the culture, climate and the region. These traditional models can be examined as precedents, which inform the architecture, rather than to provide a set of ready-made solutions.

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23 The urban space in hot-climate regions In contrast with cold climate settlement the urban space is a key factor in defining the characteristics of hot climate settlement. It is a lively, dynamic, and possibly the most important idiom in urban design. Buildings are huddled close and shade each other and creating a shaded urban space.

24 Local wind patterns Prevailing wind patterns should be studied but obviously site microclimate has its own characteristics due to the effect of topography and building patterns. Mutrah city sector in Muscat is an example of the effect of the direction of sea breeze on urban pattern. Wind scoops are inherent idioms in Gulf vernacular architecture.

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27 Shading of Urban Space Shading from solar radiation is of prime importance in the design of buildings and the urban space in hot climate regions. Research work was conducted at SQU on the optimization of proportions of urban space for maximum shading requirements. Results showed the optimum proportions of 1:1:4. Relative priorities of orientation are N, NE, SE, S, NE, NW, SW, and W.

28 solar Chart for Muscat Location

29 Shading of urban space in Muscat for proportion 1:1:1/ Heliodon model test Shading of urban space in Muscat for proportion 1:1:3/ Heliodon model test

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31 Ground Cover and Vegetation Air temperature close to the ground presents the most extreme the conditions. During the day is the highest and at night it is the lowest. Plant and grass cover decrease surface temperatures, while pavements and asphalt increase it Vegetation and trees influences solar radiation gains, humidity levels, and wind speeds and directions. Positioning of trees has direct effect on controlling wind movement and direction.

32 Urban space in the modern architecture in Oman

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36 Status of present research Present research is directed towards: Assessment of climatic environment forces influencing urbanization patterns and strategies for sustainable development in Oman. Detailed study of Climatic factors: Wind patterns and ventilation, solar exposure and shading, Air temperature and humidity, problems of local dusty winds. Drawing lessons from traditional urban and rural settlements. Assessment of the present urban pattern in terms of their interaction with climatic environment at the level of the city sector, neighborhood, and the individual building unit.

37 Studying the impact of present building regulations of street sizes, set backs on ability to attain proper shading of urban space. Presenting adjustment of building regulations in a way that considers new design constrains in response to the requirements of the climatic environment. Establishing locally adapted terms of protection from climatic extremes through ecological planning. Recommending action plans for the reduction of energy and water consumption. considering interventions to make changes toward sustainable design, sustainable development, and sustainable living habits.

38 Thank you