Can I use Great Stuff Triple Expanding foam to seal off an unused drain pipe?

[MS]

I live in a top floor condo unit and recently had a leak from my outside HVAC closet into my neighbors outside HVAC closet. The leak stemmed from my HVAC overflow pan which had a drain hole connected to said pipe which drained nowhere but right down into the neighbors closet. I have replaced the overflow pan that now drains properly out a different pipe. At this point, I want the old hole/pipe sealed off to prevent any water from draining down it. It connects to nothing and want it permanently sealed. Can I use Great Stuff Triple Expanding foam to seal the pipe?

Thanks in advance.

[homeowners]

Well, yes, it is watertight and water resistant, so it should work. They do call it "Triple expanding" to signify that it's for filling <b>large</b> gaps though. How big is the opening? This stuff is great (pardon the pun) but just sounds a little excessive. I would investigate just putting some sort of an end cap on the pipe, although that might require some pipe cutting and perhaps threading. There could be a couple of ways the pipe might have been connected to the pan, but since you were able to disconnect it - is it threaded? If it is, just screw a proper size end cap on it. Would look better and not as messy as Great Stuff.

[disqus_POoyJfmHwa]

Actually, there is no pipe (and subsequently no threading), a surprise to me. I had the work to replace the pan and redirect any overflow done by a contractor. I assumed (clearly bad move on my part) there was a pipe however when I just did some investigating there is not one. There is about a 2 inch hole that goes about 2-2.5 inches down into the plywood/wood floor of the closet and then nothing - the hole seems to just open up into space below.

I also did a little bit more research on plugging options (if the Great Stuff is excessive and messy)...would love to know your thoughts.

Thanks so much for your response!

[homeowners]

That sounds very much like an opening for a pipe, with the pipe already removed (perhaps by the contractor replacing the pan - it might have been on the way or for another reason). And the size of the opening pretty much makes your original choice - Great Stuff Triple Expanding - the best in my opinion. It is inexpensive enough, can be trimmed, painted, etc. The HD products you linked to all seemed a bit too much for the rather simple task. Just be sure to wear gloves and discard-able clothes. The foam is impossible to get out of fabric if it gets in there accidentally.

[disqus_POoyJfmHwa]

Awesome - thanks again for the response and tips. I will give it a try. Really appreciate the help. First time on this site and it really was exactly the type of support needed. Have a good one!

[homeowners]

Thank you very much for your feedback and good luck with the fix!