Indoor thermal environmental conditions near glazed facades with shading devices – Part II: Thermal comfort simulation and impact of glazing and shading properties

Abstract

This second part of the study uses a validated dynamic building thermal model for perimeter zones with glass facades (described in Part I) and combines it with a transient two-node thermal comfort model. The objective is to investigate the impact of varying exterior climatic conditions, glazing properties and shading properties on indoor thermal comfort and heating demand in such spaces under the presence of transmitted solar radiation. It is evident that selecting appropriate fenestration components becomes a trade-off between energy, thermal comfort, and lighting needs. Facades with insulating and low transmittance glass create more comfortable and stable conditions; however, there is a relationship between lower transmittance of the glazing and increased demand of primary heating needed, as well as with lighting energy use. Regardless of glazing type, shading can improve comfort conditions by decreasing radiant temperature asymmetry and extremes in operative temperature. The results show that perimeter building zones with high-performance facades (glazing and shading) can maintain comfortable conditions and even eliminate the need for secondary perimeter heating in cold climates.