The best energy efficient window treatments for cutting summer cooling costs are cellular shades, lined Roman shades, solar shades, and multi layer thermal curtains, each trapping or blocking heat differently before it reaches your living space.
At a Glance
- Cellular shades offer the strongest insulation thanks to their honeycomb air pockets
- Lined Roman shades rank second for blocking heat while adding a decorative look
- Solar shades cut glare and UV rays while preserving some outdoor view
- Thermal curtains work best paired with another shade rather than alone
- Opening and closing treatments at the right times can meaningfully lower AC use
Why Cellular Shades Lead the Pack
Cellular shades get their name from the honeycomb shaped cells built into the fabric, which trap air and slow heat transfer through the glass. They come in single cell and double cell designs, and the double cell version provides noticeably more insulation because it creates two rows of air pockets instead of one. Many current models are sold in a wide range of sizes and colors, with continuous cord, cordless, or motorized smart operation, and most install in about 15 minutes with included hardware. Cordless honeycomb options that open from the top or bottom are also common, giving households both heat control and privacy without a lift cord, often at a lower price point than motorized versions.
Roman Shades and Solar Shades: The Middle Ground
Lined Roman shades come in second for energy performance, but only when a lining is added. Unlined versions look similar yet do far less to stop heat. Shoppers can typically choose from solid or patterned fabrics and multiple liner types, including thermal sateen, which adds insulation while keeping the folded, tailored look intact. Solar shades take a different approach. As a variation on roller shades, they intercept part of the sunlight coming through a window rather than blocking it entirely, so they suit anyone who wants to keep a view while still reducing indoor heat buildup. More opaque fabrics block more sun, and some solar shades on the market block up to 99 percent of UV rays, with fabric opacity and lift style, including motorized controls, varying by product.
Where Thermal Curtains Fit In
Thermal curtains fall behind the other three options when used by themselves, but they still have a role. Paired with cellular or solar shades, they add another layer that further slows heat and sunlight from entering a room. Anyone using curtains as a standalone solution should look for two or three layer panels rather than a single layer, since the extra fabric layers are what create the insulating effect. Some current versions use two layers of triple weave fabric with a removable felt liner, delivering full blackout coverage alongside thermal benefits, and they are often machine washable.
Specialty Options for Skylights and Kids' Rooms
Homes with skylights face extra heat gain because sunlight hits the glass more directly, and honeycomb skylight shades built for that angle offer similar insulating benefits, sometimes made with Greenguard certified fabrics and cordless or smart home compatible controls. For children's rooms, room darkening shades with kid safe cordless or motorized operation address both safety and comfort, and many now come in playful patterns or muted tones meant to support better naps and nighttime sleep.
Getting the Timing Right
The type of shade or curtain matters, but so does how it gets used. Opening window treatments at night, when outdoor air is cooler, lets that cooler air work in a home's favor, while closing them again once the day heats up keeps the sun's warmth from building indoors. Done consistently, this routine reduces how often an air conditioner has to run, which chips away at monthly energy bills over the course of a season.
Which Combination Actually Saves the Most
No single product solves summer heat gain on its own. A double cell shade paired with a lined curtain, or a solar shade layered with thermal drapes, will outperform any single treatment used alone. The right combination depends on budget, how much natural light a household wants to keep, and whether motorized controls are worth the added cost for a given room.
