For the past 25 years, Southwall Heat Mirror® products have set the performance benchmark for insulating glass. Commercial and residential building owners, architects, and designers across the globe continue to select Heat Mirror to meet their most demanding requirements.

Southwall's innovative multi-cavity Superglass technology provides a whole new level of sustainable design performance.

R-20 uses three suspended films to create four insulating cavities that deliver the best known insulating glass performance of any commercially available product in the world. Combined with its high light transmission, sound insulation, and 99.5% UV protection, R-20 represents the highest standard of total energy efficiency in Southwall's patented Heat Mirror product line.

Heat Mirror glass is highly versatile, with insulating values ranging from R-6 to R-20 to meet the varying seasonal or geographic glass demands for commercial and residential projects. In hot climates, Heat Mirror glass doesn't require shading and minimizes cooling load. In cold climates, Heat Mirror glass eliminates condensation and retains heating. Heat Mirror glass enables you to fully enjoy any window's intended use - thermal comfort, views, and daylighting - while saving more energy than any other insulating glass available. More >