PRIZE WINDOWS™️ HELPING YOU UNDERSTANDING THE
ENERGY STAR LABEL
The new ENERGY STAR 7.0 specification represents an increase in energy efficiency and savings. The new label includes an additional line for northern climate zones, and lower values for U-Factor and SHGC, which translates to better insulating performance.
- U-Factor – measurement of the rate of heat transfer; indicates how well the window insulates. Values typically range from 0.25 – 1.25; a lower U-Factor means better insulation.
- SHGC – (solar heat gain coefficient) the amount of solar energy transmitted through the window; measurement of how well the window blocks heat from sunlight. Values range from 0.25 – 0.80; a lower number indicates lower level of solar heat transmitted
- The Northern Climate Zone has several recommended ranges due to colder climate and temperature variations. The lower the U-Factor, the better the window is at keeping cold air out.
- The overall lower U-Factor and SHGC values of ENERGY STAR 7.0 offer increased energy efficiency, peak performance, and savings to you.
CLIMATE ZONE MAP
U-FACTOR
U-Factor is the insulating value of an entire window system. Lower numbers reflect better insulating value.
SOLAR HEAT GAIN
COEFFICIENT
Solar heat gain coefficient (SHGC) is the amount of heat from the sun passing through the glass. Lower numbers indicate glass is keeping heat from entering your home. SHGC is measured on a scale from 0 to 1.
VISIBLE
TRANSMITTANCE
Visible transmittance is the amount of visible light passing through the glass. Higher numbers indicate glass is allowing more light to enter your home. Visible transmittance is measured on a scale from 0 to 1.
AIR INFILTRATION
Air infiltration measures how much air is entering or escaping through a window. The number shown represents the maximum air infiltration allowable by NFRC listings.
