To provide validation data for new numerical models of fenestration incorporating shading devices, tests will be required on full-sized window and shade systems. This paper gives data pertaining to a double-glazed window with internal venetian blinds. Using a technique called solar calorimetry, two blinds were tested at each of three blind slat angles and two solar profile angles. One blind was typical of commercially available products and had a significant reflectivity, while the other was painted flat black and was largely absorbing. The selected blind slat and solar profile angles allowed for the interception of both minimal and maximum amounts of solar irradiation by the shade. In all cases, the shade decreased the level of solar heat gain (by between 5% and 40%), with significant reductions occurring for the more reflective blind when it was positioned to intercept the solar energy passing through the window. It is expected that in this configuration, much of the solar energy transmitted through the window was reflected back to the outdoor environment. The shade had no significant effect on the thermal transmission of the window.

Units: SI