The project I'm working on is actually electrical, but the same question applies. I have a piece of galvanized 3/4" pipe going down into a roof jack on a garage. Right now it's sealed with some kind of tar or putty or something that looks like it's been there forever. I need to replace the piece of galvanized pipe, and will then have to reseal where the pipe goes down into the roofjack. What should I use? 20mil tape?
Talk to me fellas!