ZEMCH 2015 - International Conference Proceedings | Page 725

many phases. Passive cooling strategies have been applied in the building separately to evaluate
every study, and check the variations occurred through simulations performed by the aid of the
IES VE software.

3. Analysis and Results
Self-shading
Improving the building envelope has always been a huge demand; to obtain better design quality from the external perspectives, and attempt to reach the comfort zone for the users in the
internal space. Principally, the south building facade is the most exposed part to the direct sun
exposure, for that, south side building walls can be tilted making a self-shaded building. Furthermore, some openings could be fitted with a shading device, or a sun breaker; to avoid a direct
solar radiation. Building provides shading to the adjacent building according to its height, and
the distance between them. This hints to thinking about the ratio of the mass, its density and the
volume of compactness it exposes to the sun; to define the best shading scenario along the day
time. Self-shading is a vital strategy to be used in the hot regions, and it reduces a good amount
of heat transfer, and designer should study the region which would determine the angle of inclination of the building surfaces to reach to the optimum self-shading results.
Natural Ventilation
It’s a natural process that depends on the variation of the air pressure from high to low pressure
zones, or when there is temperature difference it will occur accordingly. Prevailing wind blows
most of the time from a certain single direction within the region. Natural ventilation as a strategy
drives air through building openings, and accordingly energy consumption for cooling will decrease. This depends on the orientation of the building, and the building elevation on the ground
as Allard (2002) mentioned, making a passage way between two masses promotes higher wind
pressure and enhances wind to speed up and cool down that path. Windows -whether operated
manually or motorized- are used widely to ventilate buildings. The numbers of openings and
distribution have major impact on the movement of air across the internal space. Alternating
natural ventilation instead of the mechanical one will be helpful in the long run; due to it’s free
of charge maintenance and fresh ventilation for the internal spaces, and according to David and
Jason (2006) this strategy can reduce the energy consumption up to 25% compared to the conventional systems.
Materials and Insulation
Building construction materials are important factors whether in hot or temperate climate; to
achieve a thermal comfort for the end-users. Diversity in materials is an advantage for designers;
to be able to choose the best combination of construction layers. As well as to structure the layers
depending on the building finishing façade skin, and in the building case, fiber cement cladding
was selected in the efficient case. In hot regions, the exposed layer to the solar radiation is the
finishing material which should be selected carefully. Thickness of the walls, air gaps, insulation
material and glazing type are elements effect on the cumulative thermal result of the building.
Balcomb (1992) describes the choice of the proper glazing as an important decision for an efficient
building. Glass with low-e values with argon gas can enhance insulation in the building and reduce the heat gain.

Designing a passive automobile showroom in hot climatic conditions

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