Electronically Tintable Glass as an Architectural Enabler

With ever more stringent energy codes and the march towards zero energy buildings, architectural design freedom using glass over large glazed areas may become more constrained as windows are increasingly viewed as the weak energy link in the building envelope. However, electronically tintable glass, also known as electrochromic (EC) glass, allows the building façade to become dynamic, changing the transmission of the sun’s heat and light in response to the exterior environment and the needs of the building’s occupants. By modulating the visible light transmission and solar heat gain coefficient across a wide range, EC glass provides both energy savings and enhanced thermal and visual comfort to the building occupants without obstruction of the view.

The availability of such a product technology provides architects with a tool that can expand design possibilities and enable the creation of exceptionally energy efficient and comfortable day lit spaces that would otherwise not be possible. This paper describes a number of case studies which illustrate the use of EC glass as an architectural enabler. In one project the designer was able to implement a ductless, naturally ventilating, heating and cooling system in a two story south- and west-facing atrium in California that would not have been possible without the use of dynamic glass. In another case study, EC glass is used in skylights to provide natural daylight throughout the building and sufficient solar control to allow for a space with no air-conditioning.