Simulating the thermal and daylight performances of a folded porous double facade for an office building in Cairo

The application of Double Skin Facades (DSFs) in hot climates is limited and their potential benefits are still under investigation. Moreover, daylight and thermal performances of the double facade are rarely studied together. In this paper a set of parameters are optimized for the design of a folded porous double facade for an existing office building in Cairo, with an aim of reducing cooling loads while maintaining daylight needs. The design and optimization processes take place using parametric design software, specifically Grasshopper Plugin for Rhino 3D modeller. These software tools were chosen due to the possibility of using evolutionary algorithms for multi-objective optimization, and environmental simulation plugins that provide real-time feedback during the early design phase. The existing building acts as a reference case to which the proposed facade is compared to evaluate its performance in South-East and North-West orientations. It is also compared to a conventional double facade. The paper discusses the effect of the design parameters on the thermal and daylight performances of the facade highlighting their preferred numerical range. Limitations of the software used are addressed, requiring verification of results using CFD simulations in future work.