The majority of residential solar panel systems are installed on the roof to provide the best exposure to the sun. But that raises a concern about what kind of damage the installation might do to the roof. Here are a few facts so you will know up front just what you will be getting into if you choose to install solar panels on your roof.
Most roofs are built to withstand at least 8 to 10 pounds per square foot of weight above and beyond the weight of the roofing material. That is usually more than enough load bearing capacity to accommodate solar panels. However, each house represents a unique installation project. Your local building inspector or a professional solar panel installer should be able to make an accurate assessment of your roof’s capacity to handle the weight of your solar energy system.
Many installers attach the solar panel mounts to the beams. This kind of installation is extremely secure and provides better load distribution than attaching the mounts to roof decking. Since rooftop installations have been common for more than 30 years, professional installers are knowledgeable about the best methods to insure stability and avoid damage.
However, it is important to consider the age and condition of your existing roof before you schedule your solar panel installation. Since the mounts will be installed over the roofing material, they would have to be removed and reinstalled if you decide to replace your roof. So if you plan on replacing your roof within the next 5 to 10 years, consider replacing it before you install your new solar panel system. That way you can avoid the additional cost of removal and re-installation.
Of course, if you are still concerned about installing solar panels on your roof, you may be able to use a ground mounted system. The same criteria apply to choosing a solar panel array location whether on a roof or on the ground. It must receive enough sunlight during the day to produce the electricity that your household needs, and it must be free from obstacles that block it from the sun. If you have such a location on you property, it may be a good alternative to using the roof.