How good does silicone work in a roof leak?

Question

We have detected three small leaks in our roof. My husband is thinking of using a sealant like silicone to stop it. I read tar is good? Is there anything better?

Answer 1

You have to know what kind of a thing needs fixing.  Are you seeing 3 small leaks below that could be related to one big thing above that is being held back by an old wooden shingle roof absorbing most of the water?  Or have you gone up and see 3 potential holes in the roof surface?  If you have something that is more like the first one you need a new roof.  If you have something like the second (on a ASPHALT SHINGLED roof) then there is a product that comes in a caulking tube in your local store right next to the silicone tubes (often in the paint department) labeled "ROOF" it is black and may look like tar or have have a more "plastic" look to it.  This is good for spot fixes.  For broader areas you have to decide if you want to attempt a proper roof repair that will look like it belongs or will accept a black spot of tar on the roof.  If you are ok with the tar then go for a can of it and a trowel that you will expect to throw away.  Clean your hands with some kitchen oil or waterless hand cleaner and some paper towels.  

If you have a flat roof, you can't see it so how it looks doesn't matter.  Usually a roofer would cement a new membrane on top of the problem or coat the area with some tar.

Some of the "tar" products will still work with a little moisture but usually you have to have a clean and dry surface that you are trying to fix.  Depending upon the nature of the repair you will have to redo the tar "fix" in one to 5 years.

Answer 2

Its hard to beat tar.  You can even get it in tubes that you apply like chaulk.  Silicone would probably work if it dried first.  Water won't bother the tar but if it's going to be visible maybe clear silicone.  Of course we know replacement of the defective roofing is the correct choice.

Answer 3

silicone short-term fix. better choice is roofing cement\sealant, available in caulk tube.

Hope that helps.

Answer 4

silicone is hard to get, it's usually in specialized art stores or on the web. An alternative to stop your roof leaking would be poly filler, its easy and you can get it from DIY stores