Assessing Thermal Comfort near Glass Facades with New Tools

Transparent facades impact the thermal comfort of occupants in multiple ways. This paper addresses such impacts both for generic glazing and for complex fenestration systems such as shades and blinds. The first step in the process of evaluating comfort for a specific façade is to calculate the solar radiation load on the occupant. The second step is to assess the person’s physiological reaction to the radiation and how this reaction influences thermal sensation and perception of thermal comfort.

A newly developed tool (SoLoCalc) uses bi-directional scattering functions to characterize the radiant transmission of complex fenestration systems. The output is then linked to an advanced physiology and comfort model. Although this paper describes its use in evaluating glass facades, the tool applies equally to buildings with smaller window-to-wall ratios, or to skylights. A case study of a real construction project shows how the tool enables a new and comprehensive approach to assessing the impact of the building envelope on user comfort.