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I know that the ABS main stack in my home is not rubbing against the floor or attic plywood openings; it is rubbing against the drywall in a interior wall when the pipe expands with the use of hot water. The pipe is 3.5" in diameter and the wall is studded out with 2x4's, so the stud bay is 3.5" as well. With such little room to add felt, I was hoping a product existed that was thinner but would still eliminate the ticking noise.

Does any sheet-like product for this application exist? I was expecting to find some sort of two-piece sheet system that would allow the sliding to occur between the sheets but I have had no luck in finding such an item on the interwebs.

  • This is one of the reasons that a 6x wall should be built for the main stack, and the stack should have been cast iron, not ABS. – Jimmy Fix-it Jan 23 '16 at 18:38
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    Cast pipes went out of style in the 70's. We usually use strips of tyvek house wrap. It keeps any pipe sweating from staining the Sheetrock. You may be able to get some scraps from a builder. We always have leftovers from window and door cutouts. – Ed Beal Jan 24 '16 at 16:35
  • So you think the wrap between the pipe and drywall would prevent the ticking sounds? I need to get my hands on some scraps. – Evil Elf Jan 24 '16 at 20:35
  • Do you think the wrap will hold up to the rubbing through the years? It is on an interior wall, so I am wondering if trying a duck cloth would be better. – Evil Elf Jan 25 '16 at 20:37
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    Are you sure it is rubbing against drywall? I suspect that instead the drywall is just acting as a speaker diaphragm to amplify the sound... – keshlam Feb 10 '16 at 15:42
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Cut out the 1/2" drywall in the affected area & hot-patch in 1/4" drywall. A gap won't wear out over time, but any & all padding, greasing or spraying will. But yes, even a slight temperature increase will expand plastic plumbing.

  • Why didn't I think of this? – Evil Elf Mar 18 '16 at 13:23
  • This is the solution, but I am going to slide some material between the pipe and drywall as a test first because I am curious now. – Evil Elf Mar 18 '16 at 13:24
  • :) A lot of times we just need another set of eyes, I know I do. But yeah, I'd even go with just paper or single thickness cardboard in the top plate's hole to get that millimeter centering, these can be stapled or tacked in place. If you have full access you could actually drive some shims in between the top & bottom plates to slightly bulge the drywall away. – Iggy Mar 18 '16 at 13:33
  • Just got done taping and mudding. This worked like a charm. 1/4" furring strips and 1/4" drywall. Perfectly silent. I hope others with the same issue find this solution. – Evil Elf Apr 2 '16 at 21:39
  • Fantastic! Me too, the expansion & contraction noises are everywhere. – Iggy Apr 2 '16 at 22:56
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Attach teflon sheets/strips to the drywall to allow the the pipe to easily slide around without noise.

such as http://www.amazon.com/dp/B000FPD674/

Or the as a tape, though the tapes are less wear resistant than the sheet/plates http://www.amazon.com/dp/B004V41BPE/

  • Any idea how tear resistant these are? – Evil Elf Feb 12 '16 at 17:20
  • It is similar to a sheet of plastic, only a bit more flexible. – Netduke Feb 12 '16 at 19:28
  • I solved my issue by using insulation between the pipe and wall. – John Peters Feb 14 '16 at 6:28
  • The issue is that I only have room to slide a piece of material the thickness of cloth between the pipe and wall. – Evil Elf Feb 17 '16 at 13:57
  • These teflon sheets might work, but I think I would have to expose the pipe on both sides to get between the pipe and wall. This is not possible without major repair, and in that case, I would just increase the size of the bay. – Evil Elf Feb 17 '16 at 13:58
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How hot would a 3" abs stack have to get to make sqeaking or ticking sounds in the drywall cavity. If it wasn't built in the last couple of years 2 X 4 studs were actually 3 5/8" wide leaving you just enough space that it shouldn't tick. I've only seen this happen on hot water lines where the hole through the floor plates were really tight, never on abs stacks. For the record cast Iron had big hubs for the joints and ween't used when I got in the trades in 72 not worth talking about. I would be thinking hard about how your hot waterline goes

  • I have the wall cut open right now. It is most definitely the stack. The copper lines are about a foot away and silent. It was surprising to me as well. The mark on the pipe moves 1/2 inch up just after 5 minutes of hot water. – Evil Elf Feb 14 '16 at 23:43
  • A thought just popped into my head here, if your ABS stack is up 1/2" in five minutes would it not be true as well that it's expanding in width at the same time and maybe the ticking sound is sideways pressure being exerted on the drywall itself and not the 1/2" linear movement up. Since the drywal already has a paper backing, there really should be no noise from linear movement on the ABS. Food for thought but maybe strapping the 2" x 4" studs with strips of ripped 1/4" plywood will give the needed room for some expansion and make sure you're not going through this again after. – Richard Feb 16 '16 at 17:36

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