Energy-Efficient Window Coverings

Q: Which window coverings block hot 🥵 solar gain the best for summer?

Answer: Awnings!

Exterior sun blockers (including awnings, exterior shades and operable shutters) are the best way to keep your home cool this summer. Curious how your window coverings compare? Or what works best in winter? Read on!

Check out the best performing options below rated by ☀️ for solar gain blocking and ❄️ for insulating in winter.

man installing storm window on the outside of a house window

Storm Windows


Designed for vintage homes with original windows, low-e storm windows reduce heat gain in summer and insulate in winter. They also reduce air leaks and you can get cash back from Chelan PUD for installing them on your home.


window with cellular shades open from top and bottom

Cellular Shades


Cellular shades with a tight fit block about 20% of solar gain. They also insulate in winter, saving about 10% on your heating bills. Opt for insulative cellular shades instead of basic honeycomb blinds.


window with curtains pulled aside by a sash

Drapes & Curtains


The performance of drapes and curtains depends on how well they fit the window and how thick and insulative the fabric is, as well as its color. Well-fitting, double layer drapes can reduce solar gain by 33% and reduce heat loss by up to 10% in winter. They work best if they are backed with white, thermal or doubled up, and there are no gaps (hung close to the window, reach the floor or window sill, and overlap panels).


window with external, operable shutters

External Shutters


Shutters are stylish and one of the best ways to block solar gain — as long as you can close them. (Decorative shutters don't work. 😉) They don't offer any winter energy savings. Internal shutters work like blinds (see below).


External louvered shade on a house window

External Shades


Like shutters, shades mounted on the outside of your windows block sun from entering your home. They're adjustable and many styles can be automatically closed with the push of a button or set on a timer.


House with awnings above window and patio doors



Awnings can reduce solar gain 65% on south-facing windows and 77% on west-facing windows. Just make sure yours don't block the winter sun, which helps warm your home for free on chilly days.


Man showing solar screen mounted outside house window

Exterior Solar Screens


Solar screens look like insect screens, but reduce glare and solar heat gain while allowing light and views in. Make sure yours can be easily removed or rolled up to let the winter sun in.


hand pulling cord of mini-blinds on window



Louvered and vertical blinds are good at reducing summer heat gain, but offer no insulation for keeping the heat in during winter. Exterior blinds work better by blocking the sun before it enters your home.


roller blinds mounted on interior of home window

Other Window Solutions

Other window solutions might look great, but they likely don't offer many energy-efficiency or comfort benefits. If possible, use the options above.

  • Roman or roller shades work best for light blocking, but don't offer much reduction in solar gain or insulation to prevent heat loss.
  • Window quilts are a little like cellular shades, but are more complicated to operate.
  • Window films are great for summer and hot climates, but can't be easily removed to allow the winter sun in.

Window coverings are a great way to stay comfortable year round while lowering your energy bills. Well-designed coverings and combinations keep the heat in during winter and the sun out in summer. Plus, they're long-lasting and many work whether you rent or own your home.


A Note About Window Management

Even the best window coverings won't mean better comfort or bill savings if they're not adjusted based on the conditions. You can manually adjust your coverings or automatically adjust them using timers or other controls.

  • Cold days: Open your window coverings to let the sunshine in and naturally heat your home. Make sure any awnings don't block the sun from pouring through your windows.
  • Cold nights: Close your insulative window coverings to keep the heat in.
  • Hot, sunny days: Block the sun's rays from passing through your windows, especially on the south and west side of your home.
  • Warm nights: Check the outside temperature. If it's cooler than the temperature inside your home, fling your windows open and take advantage of natural cooling.