MoWiTT: Mobile Window Thermal Test Facility

The Mobile Window Thermal Test Facility is dedicated to the evaluation of the thermal performance of window systems by measuring the net energy flow through full-scale sample windows in two side-by-side, room-size outdoor calorimeters. Net energy flow is characterized as a function of ambient conditions, enabling scientists to derive U-factor and solar heat gain coefficient (SHGC) properties of innovative systems. Because the facility is mobile, samples can be exposed to different orientations and climates. Accurate measurements of time-varying heat flows under realistic outdoor conditions also enable scientists to derive and validate numerical models used in simulation software, improving confidence in the specification of new products.

Joseph Klems, Staff Scientist and original developer of the MoWiTT facility (right), setting up a sample for measurement in Reno, Nevada.