I've got a few nail holes in a PVC drain pipe from the master bathroom upstairs...in the wall in my living room downstairs. The wife and I noticed this section of wet drywall tonight. And as I cut the damaged drywall out...I'm up to about a 2ft X 2ft square, and I'll probably need to cut more out tomorrow. I removed the real mushy section, but there are two sides that still feel a little damp. The hole came from a picture she hung when we moved in 6 years ago. We moved the picture about 6 months ago and removed the nail. That's probably when it started leaking. Really nasty, and I actually noticed another three smaller holes in the same area of the pipe. I need to find the best way to plug these holes up. I've read that the best solution is to cut the bad section out and get a new piece and use a coupling...BUT, the pipe is already wedged in the wall tightly and the new drywall won't lay flush if I put a coupling on there. There's also epoxy...but does that really work? I mean, there aren't many options besides ripping the entire wall out and replacing most of the pipe, but I also don't want to have to repeat this same process in 5 years again. Anyone know what I should do or what I should buy?