Resource Type: Glossary Term

A performance rating for the glass area only, excluding frame and spacer effects.

An energy rating for the entire window, door, or skylight assembly, not just the center of the glass.

Glass or glass assemblies designed to reduce unwanted heat transfer, solar heat gain, or energy loss.

A label from the National Fenestration Rating Council showing energy-performance ratings for a window, door, skylight, or related product.

A rating or performance concept that indicates how well a window resists condensation under certain conditions.

A measure of how much air passes through or around a window, door, or glazing system.

The common abbreviation for visible transmittance.

The amount of visible light that passes through glass or window film.

The common abbreviation for Solar Heat Gain Coefficient, a key rating for Arizona heat-control decisions.

A rating that measures how much solar heat passes through a window or glass assembly.