The solar panel array is the centerpiece of any solar power system. But how is it installed?
Rooftop solar arrays are mounted with the appropriate hardware designed for the specific roofing type (i.e. asphalt shingle, metal, tile, etc.). The layout is engineered according to the type of attachment needed, slope of the roof, and local wind/snow loads.
The distributed weight of a solar array is low (only about 2.5 psf), so structural modifications are not required.
Roof trusses provide strong anchoring points, or in the case of metal standing seam roofs the attachments are made directly to the metal seam (no penetrations). On average about 1.3 attachments are needed per solar panel, but this varies according to a number of installation factors.
When properly installed, all types of roof attachments are waterproof for the life of the roof and are guaranteed to not leak or result in structural damage.
Asphalt shingle roofs attachments may use a metal flashing that slides beneath the shingles, guaranteeing a dry penetration even in the event of shingle failure. Micro-flashing systems are also widely used, which provide a permanent seal on top of the shingle.
Metal roofs attachments are specialized for for the specific type of sheet, including ribbed, corrugated, standing seam roofs.
Tile roofs (concrete or terracotta) attachments replace individual tiles at each attachment point with a metal flashing that matches the shape of tile.
Flat roofs may use ballasted solar mounts without penetrations; however these systems require maintenance and are unfavorable in snowy climates. Installing a custom structure is sometimes an option for flat roofs, which allows solar panels to be tilted up for better performance.
When rooftop mounting is not a favorable option, ground-based solar arrays can be a viable alternative.