I'm wanting to replace my bathroom vanity but the amount of foam around the plumbing is making me nervous as I have no idea why it's there.

Is there something going on here that I need to be wary of? Or will I really not know until I remove it?

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1 Answer 1


It's a nothingburger. That is just cheap spray foam insulation (expanding... expanding more than the person installing it thought).

It was put there to keep insects/rodents out or to gain a little r-value. Just slice it out with a utility knife. It will come off in chunks once you get going. Then do whatever you need.

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