Exterior Treatments to Shade Windows and Save Energy
One way to use less energy and lower your utility bills is by minimizing the amount of hot sunlight that enters your home through your windows. Here are 7 ways you can shade your windows from the outside to reduce solar gain.
Awnings are probably the most common exterior treatment to shade exterior windows, and with good reason. They can reduce solar heat gain in the summer by up to 68% on south-facing windows, and 77% on west-facing windows, says the U.S. Department of Energy. In addition to their cooling effect, they can be very attractive, provide shelter from wind and snow, and enhance the appearance of your home, increasing its resale value if and when you decide to sell. Awnings come in a variety of styles, materials, and sizes. A single awning can be made for an individual window (and door, if it consists of a large pane of glass that also face south or west). Or, you can have a larger awning that stretches across all the windows on the side of a house. They can be made of metal, canvas, or synthetic fabric that’s both mildew and water resistant. Metal awnings are usually fixed in place, while awnings made of fabric can be retractable so you can roll them up in the winter or in the event of a hurricane or extremely strong winds.
Though blinds are more often thought of as a treatment for inside the home, those made from wood, steel, aluminum or vinyl can be mounted outside, as well. The slats of the blinds should fit tightly together when they’re closed to provide maximum shade. One nice advantage of blinds is that they can be partially opened to permit some light and air in. You can operate them either with a crank, or in some cases, electronically.
Curtains work well on a porch or patio where, when drawn closed, they can create a very pleasant retreat against the hot sun. Hang them from the porch line so that they drop all the way down to the ground. Make sure the fabric is heavy enough to block out the sun, and use white or light-colored fabric, which will reflect more sunlight than something much darker.
Solar mesh screens
These screens are made from a woven fabric that can block 75-90% of the sun’s rays before they pass through your windows. These screens also improve privacy during the day while allowing visibility to the outdoors. They’re effective for windows, garages, patios, porches, even car ports.
An overhang is somewhat like an awning, though it is part of the actual roof, not an additional piece of equipment you attach to the roof or the side of the house. Overhangs should be designed and built to shade the windows and door during the summer, when the sun is high in the sky, but allow warming light into the harm during the colder winter months.
Shutters that fit snugly against the window are an effective light barrier while allowing for some ventilation. They’re also protective during a windstorm or hurricane, and provide additional security against breaking and entering, should that be a concern. Like awnings, they can enhance the aesthetic appearance of your home. They’re available either as roller shutters, and will roll up and down inside a track that surrounds all sides of the window on the outside, or as a fixed-hinge shutter, which allows the shutter to swing open and closed.
Exterior roller shades are either metal or a synthetic, durable fabric that roll up into a valance at the top of the window. The fabric can be partially transparent to allow people inside the home to still be able to gaze out, but of course, the more transparent the shade is, the less effective it is in blocking sunlight. Shades are usually raised and lowered by hand, but some models can be operated by a through-the-wall crank inside the house.
To determine the best exterior window treatment to meet your needs, visit Efficient Window Coverings, a project of the U.S. Department of Energy, Building Green, and Lawrence Berkeley National Laboratory. Once you plug in your zip code and identify your needs, the site will make recommendations on window treatments for you to consider given where you live and what your energy saving goals are.
By the way, planting shade trees on the south side of your home is another effective option. “Large deciduous trees planted on the east, west, and northwest sides of your home create soothing shade from the hot summer sun and reduce summer air conditioning costs by up to 35%,” notes the Arbor Day Foundation.