Spandrel Glass
Opaque glass used in curtain wall systems to conceal structural elements, floor slabs, mechanical systems, and other building components between vision areas.
Spandrel glass is typically created by applying an opaque ceramic frit or paint to the back surface of the glass, or by using an opaque back-pan behind clear glass. It is designed to match the appearance of adjacent vision glass from the exterior while hiding the building structure.
Proper spandrel glass design must account for heat buildup (the opaque backing absorbs solar radiation) which can cause thermal stress breakage. Heat-strengthened or tempered glass is typically required for spandrel applications.