When you're on the prowl for ways to save energy that are easy to do and easy on your wallet, replacing your roof probably isn't on the menu. But that doesn't mean you can't reduce the amount of heat gain through your roof in order to reduce your AC energy bills. Both homes and commercial buildings can benefit from tips and tricks that will cost a lot less than a replacement and pay big dividends in reduced heat gain. Here are three ways you can easily cool your roof to make it more eco-friendly.
1. Radiant heat barrier
A radiant heat barrier is a thin, highly reflective piece of material that you install directly under your roof to reflect heat back out again so it won't build up in your attic space. The material is similar to tinfoil, and it should be professionally installed for best results. If you install it yourself, you should do so by fastening it to the back of the 2x4s that support the roof deck. This technique holds the barrier just a few inches from the roof's underside, maximizing the amount of heat that can be reflected directly back through it. If you install the barrier incorrectly, it will be unable to perform this function. Some common mistakes homeowners make include:
- Installing the barrier so it touches the underside of the roof—the heat will simply conduct through the barrier and radiate out the other side.
- Installing the barrier correctly, then applying foam insulation—the foam will pull the heat through the barrier and then radiate it into the attic.
- Installing the barrier on the floor of the attic, which allows the attic floor/insulation to suck the heat through the barrier and keeps the barrier too far from the roof to reflect heat back through it.
2. Cool roof coating
A cool roof coating is specially designed to help the outside of your roof repel heat. It not only reflects light rays from the sun, but it helps to deter thermal rays as well. There are even varieties of cool roof coating that can be applied to asphalt shingle roofing, although, if you decide to do this, be aware that it may void the warranty on your shingles. This is a possibility with a commercial metal roof as well, especially if you already have some type of coating applied, so make sure to check with the manufacturer and with whomever installed the roof before having it re-coated.
Effective and inexpensive shading for your roof is a long-term effort. You could simply plant a few young shade trees in a carefully selected spot, but you'll have to wait for years before they're large enough to keep the sun off your roof. You'll probably want to use this strategy in conjunction with one or two of the above until the trees grow large enough to create shade.
For more information on how to make your roof as energy efficient as it can be, talk to a contractor like WNC Roofing.