Aesthetic Aerogel Window Design for Sustainable Buildings

Abstract

Transport of heat through windows accounts for more than 25% of heating and cooling losses in residential buildings. Silica-based aerogels are translucent with extremely low thermal conductivity, which make them attractive for incorporation into the interspaces of glazing units. Widespread incorporation of monolithic-silica-aerogel-based windows could result in significant energy savings associated with the heating and cooling of buildings. However, monolithic silica aerogels do not have the optical clarity of vision glass, due to light scattering by the solid matrix, and often have surface imperfections, both of which render these materials less appealing for glazing applications. Here, we demonstrate a variety of approaches to preparing aesthetically pleasing monolithic silica aerogel by a rapid supercritical extraction method for incorporation into glazing units, including: (1) process improvements that result in monoliths with higher visible light transmission; (2) innovative mold design for the preparation of uniform aerogel monoliths; (3) glazing designs that use thinner monoliths; and (4) the incorporation of artistic effects using dyes and laser etching to prepare glazing units with mosaic-or stained-glass-like patterns in which surface imperfections are perceived as features of the design rather than flaws.