In order to secure solar panels onto a rooftop system, roof penetrations are typically done. Flashing is then required to prevent any leakage from occurring.
There are several different types of flashing that are utilized in the solar industry. These are the best to utilize for pitched roofs:
- Aluminum flashing is the standard flashing type used for the typical asphalt composite roof. It is mounted by lifting the shingles, and fixing the flashing underneath. The flashing base is made to keep water runoff away from the penetration.
- Galvanized flashing is sturdier and more expensive than the aluminum one. It is installed the same way as the standard aluminum flashing. The highlight of galvanized flashing is its durability in high wind areas, though it does require more penetrations during installation.
- Elevated flashing is another type of flashing, and it is a sturdier version of the standard aluminum flashing. It comes lifted at the area above the roof penetration to prevent water runoff from passing over it and causing leakage. Thus it is more water repellent, and therefore more expensive.
- Rubber flashing is another popular type of flashing in the solar industry. This is basically the aluminum flashing with rubber bushing fixed into the opening where the roof penetration is created. This results in the flashing being completely impervious, and consequently the most costly.
- Micro-flashing is a new and simplified modification to the traditional flashing. A stainless steel compression washer with EPDM at the base is positioned onto the shingle and bolted in place. This ensures that the shingles will not require alteration and results in a quick installation. Micro-flashing is 100% anti-leakage and the most innovative method to date, though many installers have been wary of using it because of how new the technology is. It is not yet known if it will pose any problems in a decade.