For roof mounted systems, we mount solar panels on an aluminum rail system that is fastened approximately every 32″-48″ by penetrations into roof rafters according to the racking manufacturer’s specifications. On asphalt roofs, each mount is sealed with silicone to prevent any leaks. On a standing seam metal roof, these attachments are made directly to the standing seams, with no roof penetrations. The weight of the array is less than 5 pounds per square foot, so a typically framed roof is more than adequate to carry the weight. Your roof should be in good shape before a system is installed. We can also install pole, trackers & ground mounted photovoltaic panels on a concrete foundation, if there is limited roof space or shading issues.