COVID-19 Update:

To protect the health of our staff and our customers, Efficiency Vermont offices are closed to the public. We have cautiously begun scheduling project related site visits when required. You can find more information on our safety protocols here.

We know that you need support in reducing energy costs now more than ever, and we will continue to launch new offers and programs over the course of the summer. In the mean time, our customer support team is available to help you remotely. Contact us at (888) 921-5990 or

Solar heat gain (also known as solar gain or passive solar gain) is the increased heat from the sun through your windows. Solar heat heats your home through the radiation produced by the sun. While solar heat gain is desirable in the winter to warm up chilly rooms, it’s an unwelcome side effect in the strong summer heat. Air conditioners work extra hard to overcome solar gain, so keeping the sun out is the best way to keep a house cool and reduce air conditioning energy.