by Pacific West Roofing (August 2016) www.pacificwestroofing.com
A well-installed rooftop solar array doesn’t just generate clean energy. It also needs to have a solid, long-lasting foundation, which in most cases is a rooftop. In fact, about 80 percent of today’s solar panel installations are done on flat and sloped roofs. This is because roofs are the ideal setting; they get the most unobstructed sun of any other place on most properties, they’re close to power lines, and on a sloped roof you don’t need any racks to mount the panels on.
But, what is a rooftop solar array truly worth if the roof is leaky or damaged? These installations have been growing in popularity for decades, but we still see situations where the installer did not understand or take the conditions of the roof into account.
Here are some common problems to avoid:
1. Installing New Panels On An Old Roof
Ideally, the array’s life and the roof life should be about the same. Your solar panels may generate power for 20 years, and your financing or Power Purchase Agreement could last just as long. Having such a system installed on a roof that only has about 10 good years left is asking for trouble. Many roof systems, such as a metal roof or cool roofing membrane, can last 20 years or more and are well suited to support a solar array.
2. Installing An Array On A Roof That is Unsuitable for Solar
A roof has to provide just the right conditions for your solar panels to perform well. For example, panels should be oriented toward the South or the West to get the most sun. They generally work best in cooler environments, making a cool membrane ideal. Most roofs are not designed to support the weight of a solar array or the foot traffic introduced by installation and maintenance. And in most cases, numerous penetrations will be made into the roof to mount the panels, which may be against the recommendations for many roofing systems. Unless you’re lucky, making sure your roof is 100 percent compatible with solar often requires planning years in advance.
3. Interrupting The Flow Of Water
Your roofing system is designed to shed water from the rooftop and away from the building. But, when solar panels are installed without regard for this, racks and wiring often interrupt the flow of water and keep if from draining properly. Water could even be forced upward, which usually results in a leak. Ballast material can also escape and clog drains. Repairing a roof can be much more difficult when there are solar panels installed, so it’s best to make sure these issues are addressed right away.
4. Treating The Rooftop Like A Construction Site
A good roof system is durable, but they all have their limits. A solar installer might drag racks and panels across the roof or drop tools without respect to the shingles or membrane, which can easily cause penetrations. Debris that doesn’t get cleaned up can clog drains and cause all kinds of problems. To avoid this, make sure to hire an installer who understands the needs and nuances of your roofing system.
5. Not Having a Maintenance Plan
Even without solar panels, a roof will need maintenance and regular inspections. But with solar installed, that need is heightened. You won’t get the return on your investment if your panels are covered in layers of dust or sitting in a pool of standing water. Regular roof and solar panel maintenance is always recommended to keep small problems from becoming big ones.
Many other roofing problems can arise with solar panel installations, and as installers develop new mounting methods the roofing system must always be a serious consideration.
Together, roofing and solar power make perfect sense, and we expect to see many more solar installations and clean energy integration in the future. But, we hope that you will do your part to protect your roof by choosing the right solar installer, planning ahead, and committing to regular maintenance.