An Approach to Determine Specific Targets of Daylighting Metrics and Solar Gains for Different Climatic Regions

Abstract

This study comes from an integrated approach combining daylighting and thermal aspects of building spaces. Several room configurations derived from the combination of four main design variables are tested. Width-to-Depth-Ratio (WDR), Window-to-Wall-Ratio (WWR), orientation, and climate conditions are simultaneously investigated to find the best solutions that enhance the Daylight Availability and, at the same time, diminish solar gains and total energy use (lighting plus cooling and heating). Principal Component Analysis (PCA) is the statistical technique used to outline design guidelines for Mexican climate regions, namely arid, tropical, and temperate. Hence, optimal values for WDR and WWR were recommended for specific orientations and climates. Therefore, PCA is set as the basis of a methodology to define design strategies for specific locations and climates that further lead to updating high-performance standards in buildings at regional levels. Results also showed that climate conditions, such as seasonal cloud cover, temperature, and solar radiation, are crucial when establishing target limits for the actual daylit and over lit areas. The temperate climate was able to endure up to 60% as over lit area. Instead, the arid and tropical climates tolerated up to 50% and 40%, respectively, as over lit areas.

Keywords

• principal components analysis
• daylit area
• over lit area
• total annual energy use