Windows are the biggest source of solar heat gain in your home. With the ever-increasing temperatures that come with summer’s arrival, there are steps you can take to reduce that heat gain and keep the air inside your home more comfortable.
South- and west-facing windows get the most sun during the day, so concentrate your efforts on those windows. Since dark colors absorb heat while light colors reflect it, install white curtains, window shades, or blinds to reflect heat away from the house. During the daylight hours, keep those curtains or blinds closed to minimize solar heat gain. If the size and placement of your windows create a lot of heat, you can consider installing awnings on those windows.
In the evenings when the sun goes down, consider shutting off the air conditioner and open your windows. Letting in the cooler outside air during the night will keep you rooms cool, especially without the summer sun beating down on your house. Utilize ceiling fans to move the air around in the room. In the morning, close your windows and the curtains or shades to maintain the cooler temperature. You can turn the AC back on but keep the temperature closer to 80 degrees, especially if you’re not home during the day. If you have a programmable thermostat, program it to turn the temperature back down a few degrees about 30 minutes before you arrive home.
You also need to consider the age and condition of your windows. Older windows, especially single pane windows with clear glass, do a poor job at protecting your home from solar heat gain. Rooms with old, inefficient windows can feel like an oven in the summer. Consider installing high-performance windows to improve your home's energy performance. New replacement windows with double paned glass with gas fill and low-e coating perform much better and provide you with added comfort and functionality.