Punctured water tank?

[Eggscape]

As the tanks look pregnant when fully loaded, I don’t think flat sheet foam will be easy to secure to the flexing tank.

[medora]

Right. Thought of that too. And the tank is not entirely flat on the bottom now anyway with the weld and SUPER PATCH.

[Patandlinda]

Originally Posted by medora

Right. Thought of that too. And the tank is not entirely flat on the bottom now anyway with the weld and SUPER PATCH.

I did to to replace some of our spray foam . Look for the foam that says it is thick and can be sprayed overhead . There are different foams . Good luck ! Pat

[sherminator]

You don't have to make the foam board stick to the tank - you have to only make sure it stays in place. If you can cut it so it fits close to the existing foam, you should be able to figure a way to get it stay long enough to bridge from the existing foam insulation to the foam board.
I would try using pieces of coat hanger inserted in the foam to hold the rigid board, and use your spray foam to fill the gap and onto the foam board.

[medora]

Curious - would a sheet of thick (1/2 to an inch) neoprene do the trick? This would be a whole lot easier than foam board and I can’t find any spray foam that adheres from above that doesn’t require a fancier setup (Pat, if you happen to remember what you bought let me know).