Repairing an aluminum roof can’t be done in exactly the same way that repairing a shingle roof can, but that doesn’t mean that you can’t do it. First, make sure it’s really made of aluminum and not some other metal. You’ll want to patch it with the same kind of metal that it’s made of, so that it seals and wears correctly. When you’ve determined that you actually do have an aluminum roof, you’ll need to inspect how much damage you have to it. If there are only minor problems they will be much easier to correct, but you can correct larger problems, too, if you take your time to address them. You should make sure that the area that you’re going to be repairing is clean.
If it’s not, and if there is dirt and debris (or rust) on it you’ll want to clean it well so that there isn’t anything left that could keep the patch from sealing properly. Next you’ll cut a patch from a piece of aluminum that you’ll put over the area that has the damage. Make sure that you cut it a few inches larger than the area you need to cover up, just to make sure that you can get a good seal. A lot of people use tin snips to cut the corners of the patch so that the edges can be folded under and sanded. It will help you get a strong seal, which you should make with solder.
When you have heated the solder along the edges until it runs under the patch, you’re on the right track. Continue that all the way around until there are no gaps in the patch. If you need it to stay tight to the roof while you’re doing this you can put a cinder block or something else heavy on it. Once it is sealed many people coat it with roofing cement, put a larger patch over it, coat that with roofing cement, and put another, larger patch over that, which also gets coated with roofing cement. Others feel that this is overkill.
However, it’s important that the repair be done right so that it won’t leak. If you feel more than one patch is necessary than it should certainly be used. Just take your time so that you don’t have to get back up on the roof and make the same repair to the same place next time.