Let’s say you live in a region where it is cold most of the year and your biggest concern is losing heat. If correctly installed, window shades can be one of the simplest and most effective ways to prevent heat loss. Shades that are mounted as close to the glass as possible with the sides of the shade close to the wall create a sealed air space, making it difficult for the heat to escape. During the winter, shades should be raised on the south side of the house in the daytime to let in the heat from the sunlight and then lowered at night. Dual shades are even more effective for insulating as they are reflective on one side and heat absorbent on the other. These types of shades must be drawn all day to be effective and the reflective side should always face the warmest side. Draperies are a very common form of window treatment, but it is difficult to generalize about their energy efficiency as it relies on many factors. Draperies can reduce heat gain by up to 33% if they are medium-colored and have white plastic backings. They are also perfect for summer weather as their pleats and folds lose heat through convection. Unfortunately, most conventional draperies can only reduce heat loss by 10%.

However, if they are hung as close to the window as possible with a cornice installed at the top and the drapery is sealed at both sides and overlapped in the center, you can push it to about 25%. If heat gain is your primary concern, it might be best to go with blinds. Because of the numerous openings between the slats, blinds are much more effective at reducing heat gain in the summer than heat loss in the winter.

But, the advantage blinds have over shades is that these slats and be adjusted to control light and ventilation. Heat gain can be reduced by around 45% when highly reflective blinds are completely closed and lowered on a sunny window. There is no single type of window treatment that can be energy efficient if applied to every home. Your home’s specific insulation needs are the biggest factor, but the type, color and fabric of your treatment all play a part as well. But, with this information you’ll be able to make a more informed decision about which treatment is best for you, your wallet and the environment.