Stand-offs and racking
If your roof is over 20-25 years old, it is extremely wise to install a new roof if going solar. It is impossible to warranty a roof against leaks if the roof is already at the end of its life. Asphalt shingle roofs generally last 20-30 years if built well and concrete tile roofs last 30-40 years.
Asphalt shingle roofs - Here is a photo of the IronRidge Flashfoot2 product. This is a commonly used standoff. Unirac is another reputable brand that makes a high quality product.
Concrete Tile Roofs
There are three ways contractors will attach a solar system to a concrete tile roof.
Tile hooks, or L brackets are the most popular method of installing on tile roofs because it allows the existing tiles to be left in place and the bracket is shaped around the tiles. Overall this is an acceptable method. Some may argue more torque is put on the lag penetrating your rafter but I don't personally see this as a significant red flag. I use this method often.
Here we see a tile cap. The torque has been taken off the rafter by drilling a hole through the tile and putting a cap over the tile. This creates vertical hold. But, we have weakened the tiles after grinding hold through them which will increase the chances of them cracking in the future. We want to avoid cracked tiles if possible. I don't prefer this method.
Underneath the tile replacement mounts there is no tile. We have removed it completely and replaced it with a new metal tile that is much stronger. This is a modern solution that has become popular around 2017.
Flat Roofs
Flat roofs
Flat roofs are the most difficult roofs to install on, but the Chemlink E-Curb System ensures long term water protection. Flat roofs are notorious for water pooling so this creates the scenario where the sealing needs to be just that much better.
For clay tile roofs, Rooftop Solar installs using a practice called “picture framing.” It is where we install an asphalt shingle roof underneath where the solar array will go and then put the clay tiles back around the array so it looks like there is clay tile underneath. The asphalt shingles allow a better sealing material. “Clay tiles crack like potato chips!”
Ballasted systems are installed on flat roofs without any penetrations in the roof. They are actually weighed down with bricks. The benefit to the ballasted system is that you can remove it and take the system with you without damaging the roof in the process. Or, you could put it on an older flat roof that doesn’t have the life expectancy of the solar system.
Ground Mount are installed when the owner would prefer the system to not be installed on their roof. This ends up costing much more than just installing on the roof, but could make sense in a rural area or if the roof just is not capable of holding solar.
Metal Roofs are not very common in San Diego, but we are one of the only companies who will install on a metal roofs and we are very experienced at it. If this is you, call for more information.
