Solar Panels on Roofs

Factual Questions
1

Two questions:

  1. Presumably these panels have to be nailed or screwed in. What’s the impact of all the additional holes in the roof. (Roofing tiles are also nailed in, of course, but these are covered by other tiles.)

  2. What happens if you need to repair or replace the roof? I would think you would need to remove and reinstall all the solar panels, which should add to the cost considerably. (It’s possible that the solar panels themselves protect the part of the roof that’s underneath them, but they generally don’t cover all of the roof.)

2

these are bolted to the roof. the holes made need to be sealed and inspected and maintained every bunch of years with sealing material.

you can loosen a portion if elevated on racks and reapply or repair underneath.

3

You would have to remove the entire system to re-roof the house so it adds labor beyond it’s original installation. There are systems designed to act as shingles themselves but I don’t know what the maintenance is or how people walk on them when. Since they would only be installed on one side of the roof I suspect it becomes off limits as a point of access.

4

Solar installers try to minimize the number of new roof penetrations, which has led to cases where solar arrays have been blown entirely off a roof due to there not being enough screws/bolts to hold it on. Sometimes DIY folks will fasten the array to a chimney (which is a code violation IIRC), and rarely you can find incredibly stupid setups, such as installing panels over an active furnace B-vent. An idea situation it to use a large-diameter U-bolt, installed from the underside to wrap around a rafter, with the two threaded ends piercing the roof. This way you can get a very solid attachment with perhaps only 8 penetrations (4 U-bolt, 2 legs/bolt).

It’s probably safe to say you will need to remove the solar panels completely from the roof to replace the roof, and you may have difficulty finding a roofing company who will do this for you. Most of the 2nd or 3rd-tier roofing companies are extremely “cookie cutter”, in that anything out of the ordinary which they find (or which you ask them to do, even for money) is “impossible.”

5

you can span rafters with a 2x4 or 2x6 on the flat, run a straight bolt through and have one penetration each corner, fewer if adjacent panels.

it does depend on your building codes and the design of your panels/racks and the design of your roof as to what would work. in high wind environments more robust methods would be used with likely more penetrations.