The Effect of Physical Features of Window Protective Covers on Thermal Performance of Tehran's Residential Buildings

Traditionally, among sources of renewable energy, solar energy has played a great role in providing heating and lighting for the building. The heat gain from solar energy, especially in winters, can reduce the need for heating systems and as a result the consumption of energy. However, this issue in summer time can increase space cooling Loads. One of the most important factors for improving energy efficiency in the building is controlling direct solar radiation. Considering that windows are the only part of a building, which allow solar radiation to enter directly, shading is essential to prevent solar radiation penetrating the interior. Shutters are one type of these elements which have been used in Iran's architecture .The wooden type with fixed louvers were common in residential buildings of Tehran in Pahlavi period. Despite the fact that shutters have a great impact on thermal performance, they are not used by contemporary architects in Iran. This research aims to investigate energy efficiency of window shutters with different parameters: installation place, control method and material. The results show that the external shutters with movable louvers and intelligent control have greater effect on reducing thermal loads compared to the other types.