Passive cooling and ventillation

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Structural designs that involved window designs, wall thickness and shading, roofing styles, low heat conductance material, external microclimate control, water bodies and structure stance characterized the era. The contemporary building designs should consider the historical strategies in order to utilize unharnessed resources and reduce energy consumption that leads to resource depletion (Santamouris and Kolokotsa 5). Heat is transferred through three ways, conduction, radiation as well as convention. The three form the basis for heat control ideologies. The construction engineers require having insight on the site’s climate and whether patterns to successfully employ the passive cooling techniques. Most important information they need include the sun’s positions throughout the year and direction of winds (Youtube 1). The wall and windows transfer heat across from the external environment to the internal environment through conduction. The choice of materials to comprise the wall and windows determine the efficiency of the building in blocking out undesired heat. Use of a high R-value material for walls ensures minimal heat transfer thus maintaining the inner environment cool. A low U-value material for windows acts in a similar way. … Another strategy is planting of vegetation on the roof. The plants absorb most of the heat and loose it through evapo-transpiration thus the building remains relatively cool. Alternatively, making the roof dome-shaped reduces the surface area for radiation. At least one side of the dome will be shaded at any time. Therefore, while the other side radiates heat into the doomed space beneath the roof the shaded side will be re-radiating the heat out to the atmosphere. The walls directly illuminated by sun radiate heat into the building too. The design should be such that sunshades cover greater surface of the wall to reduce radiation surface. Deep engravings on the wall increase shaded surface area thus reducing radiation area as well (Asif 11) Windows offer another media for heat radiation in and out of the building. Depending on the direction the wall faces, window-to-wall surface ratio optimization helps regulate heat transfer. The windows should comprise of material that allows in only visible light while reflecting back ultraviolet and infrared rays. Depending on the time of day and season, window shutters reduce the internal temperatures by hindering radiation (Asif 11). Heat transfer into or out of the building may be resultant of air mass movement. Gaps or openings on the walls and windows allow heat to seep into the building increasing the internal temperature. Gaps on walls should be located on sides that face away from the sun depending on geographical location. Sealing the openings between windows and walls appropriately reduces seepage of hot air into the building. However, the openings may act as a means of cooling the internal spaces