Noise in PVC DWV Pipes

When hot water drains from my sink or tub in the upstairs bathroom, there are noises coming from either inside the DWV pipe, the drywall or the wooden support structures. I’ve talked to several plumbers who’ve never heard of this. Has anyone else ever experienced this?

Ya, this is very common and is usually expansion and contraction and the friction between the points of attachment. Mine sounds more or less like a popping or ticking...

Mine sounds similar to when you bump the wall or a stud. Did you correct the problem?

No, I suppose I could but I think i would have to open the wall, which is behind a 6 foot long vanity.

Well, in my case the wall is already opened because I had to re-pipe the supply lines (I had the infamous grey plastic stuff used in the 80s - 90s). Luckily, I can see exactly where the pipe is jammed in tight between two studs. So what I'll do is re-enforce the studs with metal braces then chisel out (or something) around the pipe.