How do you know if your roof is saving you money in energy costs or if it's time to repair or re-roof in order to get the most energy efficient roof possible? Most homeowners rely on their roofing contractor -- and what costs the least to install. But educating yourself about how roofs can be made cooler and what that means for your heating and cooling bills can help you be a savvy shopper and an earth-friendly homeowner.
A roof that reflects more of the sun's rays rather than absorbing them can keep a home cooler; thus, the idea of making "cool" roofs. To better understand this, go up and stand or sit on your home's roof on a warm day. You'll find you get warm and sweaty pretty quickly!
In fact, most roofs are up to 90 degrees hotter than the air around them. To contrast that, cool roofs can be as little as 10 degrees warmer than the outside air. There are a few ways to get a cool roof on your home:
- Install one. If you're building a new home or re-roofing from scratch, you can have your roofing contractor install a roof that is made of light and reflective materials like white vinyl that can reflect light.
- Coat your roof. Several types of reflective coatings are available on the market that can help your roof reflect light and heat to save on energy.
- Insulate your roof. If the whole system -- roof and attic -- are well insulated, you can avoid losing heated and cooled air to the outdoors. Your furnace and air conditioner will run less and you'll pay less to operate them.
If you own an already existing home with a serviceable roof, and if your attic is already insulated, your best bet is to look at how you apply a coating to your roof that will reflect light.
Cool roof coatings contain white pigment and/or special reflective material. You can put them on right over most roofing materials, including asphalt. They are thicker than most paint and may be tricky to apply without any experience; your roofing contractor can typically handle it more quickly and easily than the average homeowner.
In addition to reflecting light to keep the building cooler, these coatings bounce off ultra-violet light, which can break down your roofing materials over time. That means your roof may last longer through the protection of the coating. Some brands also include additional water protection to seal your roof and increase its durability.
What if you have a roof covered with asphalt shingles? Some coatings work with these, but they could void the warranty you have with the shingles. Check to make sure before you purchase a product and begin to apply it. A better option is replacement with cool white asphalt shingles that are individually coating at the factory for reflectance.
For more information, check out companies such as Lengacher Roofing.