Heavy Commercial Serious Windows from Serious Materials is a line of energy-saving window products for commercial applications. The collection has an R-value of up to 7.0 and a U-value up to 0.14, more than two times the thermal insulation of commonly specified aluminum, thermally broken commercial windows. The windows combine SeriousGlass superinsulating glass units with fiberglass frames, enabling passive heating and cooling along with maximum daylighting. Fiberglass frames offer enhanced durability and a lower embodied energy footprint. Serious Windows also have fused corner joints and air infiltration of less than 0.01. SeriousMaterials.com
