In my two story house, I have a 3″ DWV soil stack in a 2×4 wall. When a toilet is flushed on the 2nd floor, there is quite a noise in the downstairs wall which is between a bedroom and a bathroom. I’m not concerned about the bathroom side, but I’d like to reduce the noise in the bedroom. I know the best solution would be to change the wall to get some space between the stack and the wall, but with the layout of the room, that will not be easy. Is there some way to reduce the noise without making the wall thicker?
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Replies
Assuming the stack is PVC, changing it to cast iron would probably solve your problem.
If you can open up the wall you can either change to cast iron or wrap the pipe with something. There are commercial products for this duty but a layer or three of "peel-and-stick" flashing tape should work about as well.
Another option, of course, is to double-up the drywall on the bedroom side, being sure to use gooey glue between layers.
butch
Wrap the pipe with carpet pad. Build out the wall thickness in that space only.
Soil Stack Noise
I thought about building out the wall to give space for a wrap, but the only way I think that would look decent is to build out the entire wall. There is a closet in one of the adjacent walls that is too close to that wall to allow me to do that. I also would have a doorway to modify. If is used the carpet pad I wouldn''t be able to put the pad all the way around, but maybe putting it on the two sides in the wall would help some as I think part of the sound is an echo.
Thanks
If you're not averse to opening the wall, but don't want to thicken it, then you best bet is to replace the plastic pipe with cast iron, as already recommended.
Be sure to replace as much as possible.
Since 3" cast iron has a smaller outside diameter than plastic, you could also wrap the C.I. pipe with some of the material that DanH mentioned.
Personally, I've never minded the sound of functioning plumbing.
At least it's much better than the sound of non-functioning plumbing.
Exactly.
What about putting an additional layer of 5/8" drywall over the existing wall? You would have to remove and reapply the trim on that wall, but it's also pretty straightforward.
Soil Stack Noise
I could add another layer of drywall, but if it would require reworking a door frame on that wall. If I have to do that, it wouldn't be a lot more work to increase the thickness in the wall by an inch or two. When I looked at the wall to consider adding the drywall, I see that it has a slight bulge near the ceiling, so I suspect the pipe is not centered in the wall, and unfortunately, it is more to the side that I would like to not hear the noise, a bedroom. Wouldn't getting some space between the wall and the pipe be better than the second layer of drywall?
So you're willing to add another layer of drywall but not cut out a section and replace the pipe?
Soil Stack Noise
I could add another layer of drywall, but if it would require reworking a door frame on that wall. If I have to do that, it wouldn't be a lot more work to increase the thickness in the wall by an inch or two. When I looked at the wall to consider adding the drywall, I see that it has a slight bulge near the ceiling, so I suspect the pipe is not centered in the wall, and unfortunately, it is more to the side that I would like to not hear the noise, a bedroom. Wouldn't getting some space between the wall and the pipe be better than the second layer of drywall?
Cut the wall open, cover the pipe with a couple of layers of peel-and-stick flashing membane, temporarily close the hole. See if it improves. If not, have the pipe replaced with CI (though doing so may be a trick, given that there is apparently a fitting at the top of the the wall and you don't have enough thickness for Ferncos).
Or turn up the stereo.