Given how crazy the climate’s gotten, we may be in for a very long, hot summer. In the heat of the moment, your first thought might be to crank up your air conditioner to stay cool. But that’s an expensive proposition that will use a lot of energy and wreak havoc on your electricity bill. Before you get to that point, why not take a look at your windows, especially those that let in the most sunshine, and consider ways to shade them or use sun-blocking blinds to keep the sun and heat out?
First things first. Weatherize. If you didn’t do this in the winter to keep cold air out, definitely do it now to keep hot air out and your nicely cooled air in. You can find a variety of weatherization kits in our online Amazon store or at your local hardware store.
Second, plant trees. Trees planted strategically on the sunniest sides of your home can significantly reduce the amount of solar light getting through your windows. Plus, they add value to your landscape.
Next, cover up. Chances are, your windows are only single panes of glass, maybe doubles (triple-paned glass is the most efficient, but it’s not commonly found in most houses and apartments). That means that there’s not much of a barrier between the inside and the outside of your house. Curtains or shades add an extra layer of insulation and increase the energy efficiency of each window covered. The thicker the curtains, the more energy you’ll save, especially if you mount the curtains as close to the window as possible. Otherwise, hot air will end up escaping around the curtains and into your room – and vice versa with cold air.
For energy-efficient shades, skip single louvered panels, whether made of aluminum or vinyl. Instead, aim for shades constructed in a cellular or honeycomb pattern. Here’s a picture of the double-honeycomb shades I have on most of my windows. Triple combed shades are the most efficient available, but they weren’t on the market 25 years ago when I bought my shades.
Honeycomb shades work by creating an insulating pocket of air in each cell that separates the window air space from the room air space. When not in use, the blinds fold up into a thin band at the top of my window. When down, they provide an effective barrier to the outside air, but still let enough light in that the room can be bright if I use them during the day. You can see more honeycomb options at Levolor and many other online retailers.
Roller shades, made from heavy-duty fabric, can also reduce window energy loss. To get the most out of the shade, mount them on a track that runs inside the window frame. When the shade is down, very little energy will seep into or out that window.
You can also cover your windows with insulated window quilts, like the ones I have on my french doors (right). The quilts affix to the window frame with velcro; they’re extremely effective at blocking outside air. The downside is that they let absolutely no light through so you won’t want to leave them up during the day. I actually made my own for my previous home, and they worked quite well. If you want to make your own, you can find instructions here.
Shade windows from outside. The most sunlight comes through south and west facing windows, so these should be your priorities for exterior awnings or overhangs. A wide variety are available, including those that can retract in winter to let the sun in.
Install storm windows. Storm windows add another layer of glass to your permanent windows. Ideally, your storm windows would attach so that you can still open the window and let air in when you want. I have storm windows on the glass of my front door. In the spring and fall, when the air is pleasant and cool, I lower the storm window so this fresh air can come through the screen and into my home.
Replace old inefficient windows. According to the Environmental Protection Agency, Energy-STAR certified windows lower household energy bills from 7 – 15 percent. Federal tax credits to defray the cost of new windows have expired; check with your state and county to determine if you can take advantage of local tax credits to help cover your purchase.