Islam came with many sustainability and environmental conservation principles, which appeared in all aspects of the Islamic society. This green vision of Islam is also reflected in the city planning and traditional architecture. Infact, Islamic cities were shaped by Islamic beliefs on environmental conservation and sustainability.
The traditional house adopted in Islamic architecture respects the environment in more ways than one: first by minimizing the impact of harsh natural environment conditions such as hot climate, relative humidity and solar radiation intensity, second by maximizing the potential possibilities of these conditions to achieve the thermal comfort of inhabitants and utilizing the benefits of natural energy sources such as sun and wind.
Traditional Islamic architecture relied on basic sustainability principles, which, with some modification and development, can be useful indicators for the contemporary sustainable house design.
Building with Clay or Brick
The materials are very important to protect the building from external conditions, for that selection materials are very sensitive stage due to physical properties concerns: optical reflectivity, thermal conductivity resistivity and transmissions. Also, because it is responsible of heat transfer into and out of the building.
Clay is the best natural building material, since it can provide heat isolation. It also helps to reduce the depletion of vital natural resources and carbon emissions. Clay has been widely used in Islamic world throughout the ages.
As for Brick it is one of the most important building materials used in Islamic architecture, especially in Egypt, Iraq and Morocco (where wood and stone are rare). Brick was used to build bearing walls, beams and domes. Due to providing good thermal isolation for interior spaces, if it was built in a large thickness.
The main concept of designing the traditional Islamic house was the Courtyard, using courtyard as a central point to achieve the principle of introvert, which was the lung of the house.
The great difference between the temperatures between day and night made it acts as a thermal regulator, by creating different pressure areas between the narrow-shaded streets and the courtyard in operation called night flushing.
In general, the courtyard was often centered by a fountain or salsabil in addition to fruit trees. These elements worked together to moisten the dry air and reduce its temperature. Some modifications were done to the courtyard to ensure keeping the flow of air which led adding more architecture element such as: Iwan, takhtabush, maqaad and many others.
Natural ventilation is one of the most important principles of sustainably in a traditional Islamic house, as the air speed increase the rate of heat transfer from the body to environment, it also helps to get rid of moisture, and cool the building.
The malqaf is the most important appliance to catch and enter the wind into a house. It is also considered one of the most important elements of the Islamic buildings. The malqaf defined as: an architecture element that used to ventilate the building.
The malqaf on the other hand creates different pressure zones between inside and outside. The air enters after purifying and moisturized, then been pushed out openings. At night this process is reversed. The malqaf also reduce dust and sand, which been carried by hot dry wind, where it eventually rests at the bottom of the malqaf.
There are several types of malqaf: the most important are the roof malqaf and the well- malqaf which are one-way, following the general winds direction. Then kashtil or wind towers which are multi-directional. Also, there are other simple types of malqaf such as the double wall, and badqash. Finally, there is a special type of malqaf called Badgir, which was developed in the Arabian Gulf, it is a shaft opened from above from the four sides (sometimes on only two), it has two diagonal stripes inside that catch the wind from any direction.
Utilization the soil potential is one of the principles which sustainable design depends on to benefit from natural resources. The idea of building underground depends on minimizing or determining the effect of external climatic conditions on the interior space, by taking advantage of the thermal storage potential of the mass of soils.
Traditional architecture benefit from soil to reach thermal comfort by including basement in house design, which used to be one or more underground floors. This basement could be belt multi-leveled depending on climatic conditions and functional performance. Basement could be found in the traditional houses in Iraq, which is half basement located at a depth of 1-1.2 m with openings at the central courtyard.
Traditional basements were more common in highlands, such as Iraq and Saudi Arabia, there are also examples of fully built underground houses such as in Mattmatta in Tunisia, and in south areas of Libya. Areas with High water levels in the soil did not use this method such as South of Iraq and the Gulf region.
The effective thermal performance of the basement appeared especially in the afternoons, when the external air temperatures reach its maximum limits. Traditional inhabitants used ground floor and basement in the mornings, and upper floors at evenings.
Natural lighting is the most important strategy of sustainable housing, in order to reduce the thermal load and thus providing a comfortable environment, since natural lighting is three times better in improving vision than the industrial lighting equivalent.
The problem is that windows are a major source of heat inside the building, which made traditional Islamic architecture to develop solutions to inter natural light and block direct sunlight. The most important of these are the mashrabiya, which is an architectural element that allows wind to enter and prevents the sun, these usually cover the outside of windows and balconies. Mashrabiya control light, air flow and outside expose. That made mashrabiya a strong privacy element for its narrow cartel, which used to be made of wood cones and sometimes of non-wood materials, such as marble plaster and metal. Mashrabiya first appeared in Egypt then transfer to the other Arab countries.
The traditional Islamic architecture is one of the most successful models in achieving the concepts of green design. It created beautiful harmony and fine balance between form and function. The elements of the Islamic architecture were founded to work side by side, boosting each other’s and complementing different climates as well environmental and socio-economic conditions.
The modern architecture needs to re-explore the principles of traditional architecture, choose the convenient methods to local environment, absorb the requirements of sustainable development and mix these principles with modern technologies. To conclude, modern technologies can make use of traditional architecture in creating a more sustainable world.