How do I stop the smells?
July 29, 2023 10:38 AM Subscribe
I moved into a new townhouse about five months ago and smells from my neighbor's courtyard always end up inside my place. I'm not a smoker or particularly fond of the smell of dog poop and would like it to stop.
The place next door is an AirBnB so there's a rotating cast of characters there. Mostly it's fine but lately I've noticed that any time my neighbor lights a cigarette, it feels like I'm smoking it with them. The same for joints and, sadly, any time they let their dog out to do his business; once there was a fairly strong smell of decomposition and then, for two days afterwards, the cloyingly strong smell of way too much air freshener).
At first I thought I might be imagining it/having olfactory hallucinations, but when I've thought I've smelled something my boyfriend confirms that there is a smell (though it seems to be fainter for him). After checking a few times (faint smell of cigarette inside, strong smell of cigarette when I open the back door) I've confirmed that it's definitely happening.
The contractor who came to look at the insulation in the attic (it's insufficient) was pretty patronizing and said that the air intake is in the closet upstairs, not out back. He didn't think the smells could be getting in through the HVAC.
Nonetheless my next theory was that the smells could be getting into the attic (the eaves are ventilated and go into the attic; there's a vent at top to let hot air pass straight through), and that if there were any leaks in the ductwork (it's 40 years old) there could be some air exchange there.
However, going up with a flashlight and a mask and a stick of incense didn't confirm any of that (the plume of smoke just kept going straight up, not being blown away from any part of the ductwork when the AC was on), and the thermal camera I got afterwards to take another look also didn't confirm any of it. In spite of my expectations, this 40-year-old ductwork might still be properly sealed.
That said, I did notice that the firewall between the units doesn't go all the way up; there's an inch-wide gap between the top of the wall and the bottom of the ceiling, with some very old and degraded tape hanging there looking like Swiss cheese and not doing anything. I'm not sure what kind of tape that was or what it was meant to be doing, but I doubt it was put there just for the hell of it.
I also took a look around the doors and the windows, thinking there might be some brittle weather stripping. I checked for noticeable temperature variations and even confirmed with the thermal camera that there aren't any (just 40-year-old doors and single-paned windows I'll probably want to replace when I can).
What are my next steps here? How do I track down the smell infiltration and stop it? Suggestions appreciated.
The place next door is an AirBnB so there's a rotating cast of characters there. Mostly it's fine but lately I've noticed that any time my neighbor lights a cigarette, it feels like I'm smoking it with them. The same for joints and, sadly, any time they let their dog out to do his business; once there was a fairly strong smell of decomposition and then, for two days afterwards, the cloyingly strong smell of way too much air freshener).
At first I thought I might be imagining it/having olfactory hallucinations, but when I've thought I've smelled something my boyfriend confirms that there is a smell (though it seems to be fainter for him). After checking a few times (faint smell of cigarette inside, strong smell of cigarette when I open the back door) I've confirmed that it's definitely happening.
The contractor who came to look at the insulation in the attic (it's insufficient) was pretty patronizing and said that the air intake is in the closet upstairs, not out back. He didn't think the smells could be getting in through the HVAC.
Nonetheless my next theory was that the smells could be getting into the attic (the eaves are ventilated and go into the attic; there's a vent at top to let hot air pass straight through), and that if there were any leaks in the ductwork (it's 40 years old) there could be some air exchange there.
However, going up with a flashlight and a mask and a stick of incense didn't confirm any of that (the plume of smoke just kept going straight up, not being blown away from any part of the ductwork when the AC was on), and the thermal camera I got afterwards to take another look also didn't confirm any of it. In spite of my expectations, this 40-year-old ductwork might still be properly sealed.
That said, I did notice that the firewall between the units doesn't go all the way up; there's an inch-wide gap between the top of the wall and the bottom of the ceiling, with some very old and degraded tape hanging there looking like Swiss cheese and not doing anything. I'm not sure what kind of tape that was or what it was meant to be doing, but I doubt it was put there just for the hell of it.
I also took a look around the doors and the windows, thinking there might be some brittle weather stripping. I checked for noticeable temperature variations and even confirmed with the thermal camera that there aren't any (just 40-year-old doors and single-paned windows I'll probably want to replace when I can).
What are my next steps here? How do I track down the smell infiltration and stop it? Suggestions appreciated.
Put a fan blowing outwards towards the smelly area (like inside your home, pointing towards an open or closed window). The fan I will create a positive pressure gradient so air is going OUT of your home and bad smells can’t come in because they get blown away by the fan. Note that this will allow air to suck IN to your home from another place, so think of where you’d like that place to be and crack a window there.
posted by nouvelle-personne at 10:59 AM on July 29, 2023 [4 favorites]
posted by nouvelle-personne at 10:59 AM on July 29, 2023 [4 favorites]
Yes, air filters do help! We have two different Coway models, large and small, and as long as we remember to replace the filters and keep them clean they do a great job when our pyro neighbors light their fire pit. Hopefully that's in your price range and your home is comfortable with the windows closed.
posted by rouftop at 1:29 PM on July 29, 2023
posted by rouftop at 1:29 PM on July 29, 2023
The way you find air leaks in your house is with a blower door test, which is basically a big fan that sucks air out of the house so that outside air is pulled in through all the cracks. You can often achieve a reasonable alternative to this by simply turning on all the exhaust fans that vent outside (and the clothes dryer if it also vents outside). Then you can walk around with your incense and check for leaks around windows, doors, electrical outlets, light fixtures, etc. Since you attic is vented, you'll want to check any penetrations through the top-floor ceiling carefully.
Mark any leaks with a bit of tape and then you can come back and seal them up as best as you can with tuck tape, foam rods, caulk, spray foam, new weather stripping, etc.
However, as you seal your house up more and more, you may want to think about ventilation so you aren't breathing stale air and you are better able to control indoor humidity if it is cold outside. That's when you probably want a real blower door test to quantify how much air leakage you have. If you install mechanical ventilation, like a heat recover ventilator, you can put the intake on the opposite side from the neighbour's courtyard and this should help reduce the smells in the house by replacing smelly air with fresh air.
posted by ssg at 6:22 PM on July 29, 2023
Mark any leaks with a bit of tape and then you can come back and seal them up as best as you can with tuck tape, foam rods, caulk, spray foam, new weather stripping, etc.
However, as you seal your house up more and more, you may want to think about ventilation so you aren't breathing stale air and you are better able to control indoor humidity if it is cold outside. That's when you probably want a real blower door test to quantify how much air leakage you have. If you install mechanical ventilation, like a heat recover ventilator, you can put the intake on the opposite side from the neighbour's courtyard and this should help reduce the smells in the house by replacing smelly air with fresh air.
posted by ssg at 6:22 PM on July 29, 2023
Response by poster: Thanks for the suggestions. I'll see about getting an air filter/air purifier to see if that solves it.
posted by johnofjack at 6:22 PM on July 29, 2023
posted by johnofjack at 6:22 PM on July 29, 2023
Whatever device you get, make sure it to get it a combo particulate and odor filter. Particulate filters alone, even hepa ones, won't capture tiny yet scenty odor molecules.
posted by zippy at 1:36 PM on July 30, 2023 [1 favorite]
posted by zippy at 1:36 PM on July 30, 2023 [1 favorite]
Friend works as a super, made some chronic pot-smoking tenants a DIY box fan with a charcoal layer, neighbours never complained again
posted by cotton dress sock at 1:27 AM on July 31, 2023 [1 favorite]
posted by cotton dress sock at 1:27 AM on July 31, 2023 [1 favorite]
This thread is closed to new comments.
Indoor airfilters will trap particulates, and if you install a combo particulate and organic filter (activated charcoal, I think) they remove odors really well. I used this strategy during wildfire season where the entire outdoors smelled like someone firing up a charcoal BBQ for weeks, and my indoors was blissfully smoke-smell free, and I was in a poorly insulated place.
You can start small with just a filter for your livingroom or bedroom. Leave it on 24/7 at medium or low and I'll bet your situation improves dramatically. If it works you can get units to cover other rooms.
posted by zippy at 10:48 AM on July 29, 2023 [2 favorites]