Shady Business: Reducing Heat Island Effects From Paved Areas Near Your Home

If you're a homeowner who has bought a new-to-you home -- not a newly built home, but an existing one that has become your new home -- you know that redoing landscaping and yard features is often necessary. What worked for the previous homeowners might not work for you, so you have to take a good look at what you want to do and can afford to do.

One issue you might encounter is too much heat given off by paved areas, including driveways, pathways, and patios. There are modifications you can make to your house, the surrounding plants, and the paving itself to reduce the amount of heat that surrounds your house in hot weather.

Light Pavement

Just as light clothing reflects heat and keeps its wearer cooler, light pavement can reduce the amount of heat absorbed by the pavement. This may sound like a strange way to avoid extra heat because a lot of heat is being reflected back up and away. But that heat doesn't make a beeline for your house. The heat that really causes you a problem is the heat that hovers at ground level, absorbed by darker surfaces. That makes the general area around the pavement feel hotter -- basically, it's a mini urban heat island.

By using lighter pavement, you reduce the heat island surrounding your house. The Heat Island Group at Lawrence Berkeley National Lab in the United States notes that the difference in temperature between light and dark pavement can be a good 30 degrees Fahrenheit, or 17 degrees Celsius. Even in Canada and in cooler weather, urban heat island effects can be quite noticeable.

For example, the University of Regina's Encyclopedia of Saskatchewan notes that in 1996, Regina saw temperatures that were 3 to 5 degrees Celsius higher than the rural areas around the city -- in usually very cool October. If that rise in temperature can happen when the city is only 7 degrees Celsius, imagine how much hotter a paved area can be in summer.

Reflective Pavement

If you have a dark driveway, like asphalt, and don't want to have that pavement replaced, another thing you can do is coat the pavement with a reflective binder or coating. This acts as a shield against the heat that the pavement would normally absorb, again sending it back up and away from the house.

Pergolas, Awnings, Shades, and More

You might want to look into carports, awnings, and pergolas covered with vines if you have a lot of paving. These directly shade the paved areas and prevent the pavement from heating up that much. You'll still get some heat, but it will be much more bearable than if the paved areas were uncovered.

Shrubs and Trees

Shading paved areas from the side is important, too. Awnings, carports, and other shades work from the top, but they often leave the sides of the area exposed to afternoon sunlight. Adding shrubbery and taller trees can block out this hotter light. If you live in a quake area, you might consider tall hedges instead of trees. Canadian Living suggests Hick's Yew and Peking Cotoneaster, both of which can reach nearly 10 feet.

If you have more questions about reducing heat effects from pavement, talk to paving contractors who specialize in reflective coatings and in reducing heat absorption. They know how to protect nearby structures from extra heat. And when you finally decide to replace your home's paving, they can help you with that as well.