Stylish Insulated Curtains for a Cooler Summer and a Warmer Winter

The best multi-lined curtains for keeping your home climate controlled no matter what the season

Curtains that offer insulation are the best types of drapery for most homes — large or small, drafty or stuffy — because they keep hot air out during the summer and cold air out during the winter. According to the United States Department of Energy in their brief “Update or Replace Windows,” “heat gain and heat loss through windows are responsible for 25%–30% of residential heating and cooling energy use,” making insulated curtains that effectively aid in sealing windows the most energy efficient.
Given that replacing either windows or their frames is expensive — from the materials involved to the complex installation required — choosing insulated curtains as a way of keeping your home climate controlled is a superior option for budget-conscious households. Thankfully, a number of attractive, on-trend options for multi-lined drapes exist on the market, making it fairly easy to update both your home’s energy efficiency and interior decor at the same time.

For Warm Months

For hot summer months, one should consider blackout curtains, which banish both light and heat from a room. Filtering out ultraviolet, visible, and infrared right from a room through blackout curtains is one of the most effective ways to maintain a cool space during oppressively hot, overly bright summer days. Consider pairing the blackout curtains with a sheer lining if natural light is important to you; as long as the blackout curtains cover the edges of the windows (both the sides and the upper and lower corners), much of the heat that could escape from the outdoors into the home will be kept at bay. However, Con Edison spokesperson Allan Drury, quoted by Mary Farrel in her article “Beat the Summer Heat With Window Coverings” for Consumer Reports, recommends keeping blackout curtains closed whenever possible “on the side of the house or apartment where the sun is coming in.”

Avoid sheer Roman or roller shades as they will not effectively cover the sides of the windows unless they are quilted. In her article for Consumer Reports, Mary Farrel does endorse “Quilted roller shades and Roman shades with several layers of fiber batting,” however, as when properly insulated and completely opaque, they can be just as or more “effective than other soft window treatments.” DrapeStyle offers custom Roman shades, which can be optimized for energy efficiency with “optional blackout linings.” Heavy blackout curtains will be held against the sides by their own weight, capturing the heat that leaks in through unsealed frames. Adding a valance to each window atop the curtain rod is an extra step that will complement the sealing effect provided by blackout curtains. If possible, consider pale-colored curtains that will not attract heat, as they will communicate that heat into the room over time.

For Cold Months

For cold months, multi-lined curtains or curtains paired with a separate lining are best; those with flannel linings are ideal because they effectively retain heat. Flannel is also the most commonly recommended fabric for cold weather clothing. Flannel is fairly loosely woven, which one might think would be less effective at retaining heat due to the open spaces through which air might pass, but a loose weave is actually quite necessary to locking in warmth. As Bryan Horn notes in his article “Why Flannel Clothing is a Winter Wardrobe Staple” for, the “loose weave [in flannel fabric] creates air pockets between fabric fibers…[and because] air is a great insulator… the many air pockets in flannel fabric” are what help retain heat against the body and indoors when it is cold outside.

Furthermore, according to the article “The Best Energy Efficient Curtains & Blinds” by, which focuses on energy efficiency in small spaces, thermal, flannel-lined curtains can “reduce heat loss by as much as 25%.” The site continues, explaining that thermal curtains are “special draperies that are fitted with a dense lining, the material [of which] is heavy and its density makes it perfect for blocking unwanted noise and sunlight and also retaining heat.”

The best thermal curtains have several layers of lining, notes Andrea Hannah, interiors writer for Bustle, and are darker in color, the opposite of what you would want when trying to keep a room cool. Consider DrapeStyle’s Parker Drapes for a living or bedroom, as they are both stylish, with a trendy but classic color-blocked lateral stripe along the bottom, and practical with their “thermal flannel interlining which can reduce energy costs by 33%.” If you cannot find a pair of thermal drapes with flannel insulation that fit your decor, consider purchasing a lining and set of curtains separately. While it may feel a bit bulkier and take up more space, the effect will be fairly similar.

Fitting Curtains for Best Results

Experts agree that curtains should be fitted closely if energy efficiency is the goal, especially in homes that have poorly fitting windows or loose frames. Curtains should be hung close to the ceiling, far above the top of the window frame, and should fall close to or along the floor, pooling if necessary. This will prevent the cold or heat from entering the home through weak points in the window frame by completely encapsulating it. Keep in mind that most thermal or multi-lined curtains are far heavier and denser than other curtains, making them more difficult to remove and clean. However, many are machine washable if the unit is large enough to accommodate at least one of the panels at a time.
No matter where you live or the size or shape of your windows, blackout or thermal curtains will work hard to improve your home’s energy efficiency, keeping you cool all summer long and warm throughout the winter.