I've been puzzled for months trying to identify how odors from the neighboring townhouse are seeping into mine. I initially suspected shared ducting or exhaust spaces, but I'm starting to think it might be due to plumbing pipes. Besides ensuring that pipe openings are sealed tightly, are there other methods I should consider? Would it make sense to blow insulation into the walls to further reduce odor leakage? I'm worried that if I seal off those pipes, it could trap the smells somewhere else.
2 Answers
When the exhaust fan runs, it creates negative pressure which can suck air (and smells) from any small gaps in the construction between your home and the neighbor’s. Try only using the fan when really necessary, and make sure to find and seal those little gaps around pipes and electrical boxes. That can really help keep the smells contained where they start.
Sounds like you're dealing with plumbing vents. If the odors are concentrated in your first-floor powder room, that's a big clue. The smell could be coming from pipe openings, especially if they’re less than airtight. Maybe have a look at that area and see what's around the plumbing. Caulking gaps in those places could really help.
That makes sense! The powder room is where it's strongest, and I appreciate the tip about checking the pipes. I'll definitely take a closer look.
I usually turn on the fan only when I notice a smell, thinking it helps clear the air! If I seal the gaps and my neighbor is still being smelly, would those odors just linger in the walls?