While painting, my wife discovered some mold on top of the baseboards, and being curious I investigated. What I found pulling the baseboards is they were covered in black mold on the backside, as well as the bottom of the drywall. On further investigation, the source was the joint of a 3" vertical DWV pipe, which had a slow (but consistent) water leak.
I cut out drywall to access the joint, then cut out an 8" length of the pipe, including the joint section. I bought two Fernco shielded couplers for 3" PVC (P3005-33), and a short section of 3" PVC pipe. When I went to replace, I realized the vent pipe was NOT 3" PVC Schedule 40 pipe, but something smaller (I measure about 3.25" OD). I thought it was Schedule 30, but one supply store said 3" PVC wouldn't go down that far.
For the life of me I can't find this small of 3" pipe at any of the big box stores, or local plumbing supply stores (I have one plumbing supply store left to go ask, though), let alone the shielded couplers I was planning to do to make this repair.
So my questions are:
- How would you repair this vent pipe? (about 8" run that is currently cut out)
- Where can I get shielded couplers and repair pipe, that is 3.25" OD? Anywhere recommended online?
- (an aside) Is there any problem with leaving the vent pipe open currently? We won't be using the bathroom until everything is repaired.
UPDATE Thanks for the help. I found from a local plumber that it was an SDR 30 pipe, which I found at a local plumbing store (big box stores didn't carry). No shielded couplers, but used some slip couplers and seems to work well. But now water coming up from the slab where the pipe comes through... will create new question.