Odd shaped roofing waterproofing challenge - Please help


If the welder was able to grind way the rust, you may want to invest some sweat into it and do the same. Whatever you decide on, bare metal is a better substrate than rusty metal,especially for a coating.


@MPA Yeah, the ice and water shield may not be enough, secureness wise. Might need something better like peal and seal, would seal better to the metal. I was thinking putting it under the flashing running it up and down the wall. And I am assuming you meant “slide down” which I would agree with. However, if you do one solid strip the whole length, it should stay in place since it will be trying to slide down both sides of the dome.

@patchap I used to be a welder and grinding that whole thing would be a nightmare. Would take forever and it would be dangerous, if done with a handheld grinder and a wire wheel. Especially getting the middle of the dome where you can’t quite reach from the ladder without tipping it. Ladders and homeowners sometimes. Any welder would be like, you better pay good for it.

@nothingincommon You don’t have to nail down the ice and water shield as it has a sticky backing on it and the shingles are nailed on top of it when doing a valley or around flashings. It isn’t made to be in direct exposure though. Now that I think about it, I’ll take that advice back.

That black tar you see up there is roofing cement. You can get a 5 gal bucket for around $50. It is messy and tricky to be applied without making a mess. All you need is a trial. Watch some tips and tricks before you do it. I hate that stuff.

Test some things out. Get some good caulking first, NP1 should do the trick, and run the beads. You could do this yourself for cheap, just be careful of falling. Have someone hold the ladder. Would take less than an hour I would think. Get a good solvent for cleaning the metal and follow the instructions. If it leaks, try some peal and seal over the caulking. Would be harder due to the shape of it, but another fix you could do yourself. If it still leaks, time to consider some more expensive options.

That thing would look good with some Native American style patterns painted on this inside walls and dome. Expensive to hire someone though, but fun do it yourself.


Anything on a roll is going to be a lot of work to properly flash and the into the wall with everything being round, even for an experienced roofer. If looking for DIY options I would go the coating route. Just my two cents.


What about starting cheap and building up? If silicone works, he could only be out a little and have the solution. Or if peal and stick works? Do you think this would create too much junk to do a proper repair in the future? That would be my only thought is if it doesn’t work, what are the future ramifications for fixing it “half assed”? Pile shit on shit?


last pic i promise.

ok so I will:

  1. get the rust remover and clean up the surface as much as possible
  2. silicon the side seams
  3. apply some kind of cover product
  4. put flashing on the seam? ( can you curve flashing?)

Is this correct?


I would use tape and trowel grade silicone on the seams and the wall joint, then coat the entire thing with 2 coats of silicone coating applied with a roller.


MPA is right. You have a big gap you can fill. Just put it in thick and you won’t have any problems out of it.

Are you a DIY kind of person?