Impact of Façade Characteristics on Energy and Daylighting Performance of Medium Office Buildings in Hot Humid Climates

The primary objective of this research was to analyze and test the impact of various façade design variable modifications on medium office buildings’ energy and daylighting performance in hot humid climate zones. Based on the results of this analysis, the optimum variable modification set which demonstrated the most optimum results for the energy and daylighting performance of the building was further selected. The research used simulation approach. The baseline building was a hypothetical new-constructed rectangular medium office building with an aspect ratio of 1.5 and located in Houston, TX, the representative climate for climate zone 2A (hot humid). Independent variables and their tested options analyzed in this study include: building orientation (facades with higher area facing North and South, facades with higher area facing East and West, facades with higher area facing North-West and South-East, and facades with higher area facing North-East and South-West), window to wall ratio (WWR) (20% (Baseline), 35%, 50%, 65%, 80%), glazing types (Double-pane Clear, Double-pane Low-E, and Triple-pane Low-E), and shading devices (horizontal overhangs (Type1-3’ depth/6’11” height/ 2.8’ side projection width), and vertical fins, (2’ depth/5.2’ height/2’ distance), and Type-2-3’ depth/6’11” height/ 2.8’ side projection width), and vertical fins. (3’ depth/5.2’ height/3’ distance). The dependent variables were energy use intensity (EUI), spatial daylight autonomy (sDA), and annual sunlight exposure (ASE). The results demonstrated that option set with facades with higher area facing North and South, 35% WWR, triple-pane low-E glazing type, and with shading device type 2 resulted in 10% lower EUI value, 42% higher sDA percentage, and 31% lower ASE percentage compared to the baseline.