Energy Star Rating

Solatube is proud to offer our customers products that have earned the government’s ENERGY STAR® label.

U-Factor: U-factor is a measure of the heat loss from the interior to the outside through the skylight. The lower the value the lower the rate of heat flow. Heating and cooling bills are reduced when less interior conditioned air flows to the outside. English units are given in BTU/hr-ft2-°F. To convert to metric units, apply the following formula:  1 Btu/h ft2 °F = 5.6783 W/m2 °K Solar Heat Gain Coefficient (SHGC): SHGC defines the fraction of solar radiation admitted through the skylight and measures the ability to block heat caused by sunlight. The lower the SHGC, the more it reduces air conditioning costs.


• ENERGY STAR is a government-backed program that helps consumers identify energy efficient products.
• Every ENERGY STAR qualified window, door, and skylight is independently tested and certified to perform at levels that meet or exceed strict energy efficiency criteria set by the U.S. Department of Energy.
• ENERGY STAR requirements for windows, doors, and skylights vary by climate zone.

For more information on the ENERGY STAR program, please visit

Posted by Chris Teel