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Learning, Sharing, and Teaching => Do it Yourself Discussion! => Topic started by: dragoncar on February 22, 2016, 05:58:05 PM

Title: What's that smell?
Post by: dragoncar on February 22, 2016, 05:58:05 PM
When we open all the doors/windows on our first floor, an odor permeates that I can only describe as "kinda like pot, only not."  It's a stanky herbal smell (akin to rotting flowers?) but I don't really think the previous owners hid pot in the walls.  My wife can't smell anything, and I've had some guests who said they only noticed it after I pointed it out.  Suffice it to say, it hasn't been a high priority since it's not that objectionable, and we don't leave the windows open very often.  But over time it's starting to become a quest.

Anyone have an idea what this is based on my description of the smell?

I've considered a dead animal, but we only smell it when the windows are open and it's been there for over a year (I heard they decompose faster than that?)

We do have plants outside our windows, and I've stuck my nose in there many a time but I don't get the same smell (and the air around the windows doesn't smell either).

This leads me to believe it's coming from within the house.  I've smelled outlets, heating registers (no smell when running the forced-air heat), and ceiling electrical boxes without success.

My last thought is that it's under the house, coming up through the outlets or similar.  It's a little hard to say, because you get used to the smell quickly, and it permeates, so it's hard to determine the source by sniffing around.  I've even tried going outside for a few minutes to recharge my nostrils, and then coming back in.  It takes some time to permeate, so I'm also trying to sniff around immediately after opening windows, but this is an extremely part time project.

I haven't made it under the house yet, but I'm just wondering what you think I might find.  Would mold smell like pot?  A rotting corpse?  I'm a little scared to go down there because of spiders and such.  But I have stuck my head down with a flashlight and didn't see or smell anything.  Just smells like dirt. 

Could it be something from the plumbing/vent stack?  It does not smell like sewage.

I'll also note that the upstairs does not smell at all... it's gotta be at the ground floor.  The previous owners didn't have any pets (don't know about before that).  I'm unaware of any infestations
Title: Re: What's that smell?
Post by: bobechs on February 22, 2016, 06:26:51 PM
Maybe it's you.

You'll never know for sure because you can't smell the place when you're not around.

Title: Re: What's that smell?
Post by: dragoncar on February 22, 2016, 06:47:53 PM
Maybe it's you.

You'll never know for sure because you can't smell the place when you're not around.

LOL... yes maybe when I walk upstairs I stop stinking, and when I go back downstairs I stink it up again

Also not mentioned above, but it's not coming from any cabinet, drawer, sink, appliance, bathroom, laundry room, potted plants, or closet that I can tell (those smell normal).  Or the garage.  None of the house perimeter has this smell.
Title: Re: What's that smell?
Post by: Basenji on February 22, 2016, 07:23:31 PM
You would know a dead animal smell. We had something die in a back room wall, no mistaking it. I just Googled "strange house smell like pot" and you are not alone. One person claims bat poo smells like pot. Other suggestions were seagrass baskets and stinky shoes. Another one: hemp insulation on plumbing is apparently a thing.

My fave comment from the Bogleheads site on a strange house smell:
Quote
Check your attic to see if you have an old boglehead hiding away up there. They often do that to save money on housing. After awhile they can smell like a skunk.
Title: Re: What's that smell?
Post by: dragoncar on February 22, 2016, 07:44:18 PM
You would know a dead animal smell. We had something for in a back room wall, no mistaking it. I just Googled "strange house smell like pot" and you are not alone. One person claims bat poo smells like pot. Other suggestions were seagrass baskets and stinky shoes. Another one: hemp insulation on plumbing is apparently a thing.

My fave comment from the Bogleheads site on a strange house smell:
Quote
Check your attic to see if you have an old boglehead hiding away up there. They often do that to save money on housing. After awhile they can smell like a skunk.

Thanks, I definitely read that bat poo thread!  That's why I mentioned no infestations, but maybe I just have to look harder.  It will require crawling around under the house which I'm going to do once I get one of those suits (I did it once w/o the suit and it was a mess).  I do have some vent insulation falling down, so I want to fix that while I'm down there.  And put down a vapor barrier while I'm at it (nicer to crawl on, and the soil does get moist down there during heavy rains).
Title: Re: What's that smell?
Post by: Basenji on February 22, 2016, 08:02:07 PM
We got our crawlspace lined and the bottom of the house insulated a while back and it totally fixed some strange smells coming up from the wet muck. Our favorite was the neighbor's cat pee smell while it hung out near the hot water pipes under the radiators. But never a weed smell...
Title: Re: What's that smell?
Post by: dragoncar on February 22, 2016, 08:17:54 PM
We got our crawlspace lined and the bottom of the house insulated a while back and it totally fixed some strange smells coming up from the wet muck. Our favorite was the neighbor's cat pee smell while it hung out near the hot water pipes under the radiators. But never a weed smell...

It IS possible it's old urine of some kind under the house... it's just not smelling like my experience of cat pee

Title: Re: What's that smell?
Post by: worms on February 23, 2016, 01:22:55 AM
In some cases men and women smell things differently.  Generalising wildly here, but men are more attuned to some animal smells, women to herbal smells - goes back to role differentiation in our hunter/gatherer past.  Women are also better at detecting 'off' smells in food. Men better at detecting 'predator' smells.

I can be walking with my family and suddenly get a strong smell of fox.  Wife and daughters don't notice it at all.  Walking into the local cattle market for lunch, I smell the food, female colleague only smells the cow-shit.

So back to your case, I would wonder if some animal is marking territory just outside your windows.  That might explain why you smell it and your wife doesn't (assuming you are male) and why you don't smell it upstairs.
Title: Re: What's that smell?
Post by: dragoncar on February 23, 2016, 01:37:34 PM
In some cases men and women smell things differently.  Generalising wildly here, but men are more attuned to some animal smells, women to herbal smells - goes back to role differentiation in our hunter/gatherer past.  Women are also better at detecting 'off' smells in food. Men better at detecting 'predator' smells.

I can be walking with my family and suddenly get a strong smell of fox.  Wife and daughters don't notice it at all.  Walking into the local cattle market for lunch, I smell the food, female colleague only smells the cow-shit.

So back to your case, I would wonder if some animal is marking territory just outside your windows.  That might explain why you smell it and your wife doesn't (assuming you are male) and why you don't smell it upstairs.

That would make sense, and we do get quite a few animals leaving gifts around the yard, but we spend a lot of time outside and I never smell this... Nor do I smell it when I specifically sniff around the perimeter.  It's possible it just gets pulled in and somehow concentrated.  Don't know

I do have a better sense of smell than most (not bragging, but I'm pretty sure I'm one of those super tasters.  Once won a stupid baby shower contest where I correctly guessed baby food flavor of Apple-cherry-pear or something ridiculous like that, and I don't even like fruit or eat it often). 

My wife on the other hand has an olfactory deficiency-- I'll be like don't eat that it's definitely bad and she won't smell anything
Title: Re: What's that smell?
Post by: SomedayStache on February 23, 2016, 02:37:48 PM
When we were buying our house and doing the walk-thru with a home inspector he looked in every air vent.  (We have floor vents in this house.)  From one of the bedroom floor vents he reached his arm in and pulled out a weed pipe.  He made some comment about how this is a common finding in the vents- especially from children's room (presumably teenagers).  It's an easy place to stash things you don't want your parents to find.

So...check your vents?  Maybe you are actually smelling old pot.

But then wouldn't you smell it more when you are running the HVAC vs opening the windows?  Hmm, maybe this isn't the answer.
Title: Re: What's that smell?
Post by: dragoncar on February 23, 2016, 03:05:53 PM
When we were buying our house and doing the walk-thru with a home inspector he looked in every air vent.  (We have floor vents in this house.)  From one of the bedroom floor vents he reached his arm in and pulled out a weed pipe.  He made some comment about how this is a common finding in the vents- especially from children's room (presumably teenagers).  It's an easy place to stash things you don't want your parents to find.

So...check your vents?  Maybe you are actually smelling old pot.

But then wouldn't you smell it more when you are running the HVAC vs opening the windows?  Hmm, maybe this isn't the answer.

Yeah no sme when running hvac so I doubt it's the vents
Title: Re: What's that smell?
Post by: Lulee on February 23, 2016, 04:48:49 PM
In my apartment, even after more than three years here, if the humidity is up and the air still, I get a faint cigarette smoke odor (a smell I’m sensitive to) even though no one has smoked inside all this time and perhaps during the last tenant’s residency.  Opening windows usually helps clear it out.  If there was truly heavy duty pot smoking done by the previous inhabitants of your place, it might have permeated into the walls and now comes out when you open windows if that raises the moisture level.
Title: Re: What's that smell?
Post by: BlueHouse on February 23, 2016, 06:01:23 PM
You asked about your plumbing/vent stack.  Is there any plumbing nearby? 

I had a strange smell in my new house in the bathroom, but it only came  once in a while.  I sort of narrowed it down to the first time I entered the master bath in the morning or the powder room after an extended time (days).  Sometimes I thought it happened when I turned the water on and sometimes I thought it happened when the HVAC turned on for the first time in the morning.

The smell can only be described as a cross between sewer gas and chocolate.  I finally got rid of it by filling my sink all the way up until the water could go down the overflow drain.  I let A LOT of water go down the overflow. 

Could this be it? 
Title: Re: What's that smell?
Post by: dragoncar on February 23, 2016, 07:01:50 PM
You asked about your plumbing/vent stack.  Is there any plumbing nearby? 

I had a strange smell in my new house in the bathroom, but it only came  once in a while.  I sort of narrowed it down to the first time I entered the master bath in the morning or the powder room after an extended time (days).  Sometimes I thought it happened when I turned the water on and sometimes I thought it happened when the HVAC turned on for the first time in the morning.

The smell can only be described as a cross between sewer gas and chocolate.  I finally got rid of it by filling my sink all the way up until the water could go down the overflow drain.  I let A LOT of water go down the overflow. 

Could this be it?

There's a bathroom, but the smell doesn't come out of there.

Lulee has an interesting theory but I'm not in a humid climate

Maybe this is from the famous dirty construction workers leaving used chewin tobacco in my walls
Title: Re: What's that smell?
Post by: big_owl on February 24, 2016, 04:13:34 PM
It's the smell of death around you...

Am I the only one who started singing some Skynyrd to himself?
Title: Re: What's that smell?
Post by: arebelspy on February 24, 2016, 04:38:18 PM
(https://i.imgflip.com/cmfik.gif)
Title: Re: What's that smell?
Post by: Basenji on February 24, 2016, 05:14:48 PM
It's the smell of death around you...

Am I the only one who started singing some Skynyrd to himself?

Nope, did the same
Title: Re: What's that smell?
Post by: Gone Fishing on February 24, 2016, 06:34:43 PM
Got kids?  They can be responsible for all sorts of evil smells....
Title: Re: What's that smell?
Post by: dragoncar on February 24, 2016, 08:33:42 PM
Haha... I know I deserve all the humorous responses I get!

No kids.

The past couple of days, I've noticed I smell a musty smell (like an old wet towel) when I pass by a certain spot.  Windows closed.  Although they aren't similar smells, perhaps they are related.  It's possible the kitchen water supply/drain runs past that point, and maybe it's leaking. 

More likely to be the drain since I've done leak tests before by observing the water meter.
Title: Re: What's that smell?
Post by: FIRE me on February 24, 2016, 10:40:32 PM
Haha... I know I deserve all the humorous responses I get!

No kids.

The past couple of days, I've noticed I smell a musty smell (like an old wet towel) when I pass by a certain spot.  Windows closed.  Although they aren't similar smells, perhaps they are related.  It's possible the kitchen water supply/drain runs past that point, and maybe it's leaking. 

More likely to be the drain since I've done leak tests before by observing the water meter.

You could try renting a FLIR camera from Home Depot. If you have any damp or wet walls, floors or ceilings that may be the source of the smell and the FLIR cam will reveal it by the temperature difference.
Title: Re: What's that smell?
Post by: ShoulderThingThatGoesUp on February 25, 2016, 10:40:11 AM
It's the smell of death around you...

Am I the only one who started singing some Skynyrd to himself?

Nope, did the same

Well, now I am.

Is there a particular time of year you open your windows? Does the pressure seem higher inside the house, or outside, when you do that? At my house there's a usual direction of air flow - you can tell by which doors like to close by themselves when the windows are open, which is all summer for me. Look in the source direction.
Title: Re: What's that smell?
Post by: dragoncar on February 25, 2016, 12:28:34 PM
It's the smell of death around you...

Am I the only one who started singing some Skynyrd to himself?

Nope, did the same

Well, now I am.

Is there a particular time of year you open your windows? Does the pressure seem higher inside the house, or outside, when you do that? At my house there's a usual direction of air flow - you can tell by which doors like to close by themselves when the windows are open, which is all summer for me. Look in the source direction.

In the summer we open the windows to cool off the house after dark-- the hot air flows up, but there's not really a horizontal flow since we usually only open windows on one side.

On warm winter days (like the other day), we open the windows to try to warm up the house.  So the flow is still probably up, but maybe the cold air is actually sinking down.  Despite the mediocre insulation, the house can stay in the low 60s all day, even if it's in the 70s outside (this is really nice on hot summer days though).   

I say the flow is up due to the stack effect, but I think the smell still occurs if only downstairs windows are open, or even just a single downstairs window in the area where the smell originates (either the living room or kitchen windows will cause the smell, they are adjacent). 
Title: Re: What's that smell?
Post by: dragoncar on February 26, 2016, 06:00:50 PM
I know you are all completely riveted by my smell question, so I'm providing an update.  Went under the house today, and saw/smelled nothing.  I also tried running the whole house fan (exhausts through attic) with no windows open.  Checked every outlet and other penetration I could think of -- air was infiltrating but no smell (at any specific penetration or even in general).  So now I'm really stumped.  I'm leaning towards it being the gardenias we have outside the windows, but as I mentioned they do not smell that way when I'm outside.  Perhaps the smell reacts with something else once it gets inside to make it more noticeable.

I also noticed that my foundation perimeter seems not to be fully resting on the dirt.  It looks like there are piers, with perimeter between the piers.  It seems the ground has settled below the perimeter (in some locations I can see underneath the foundation).  So basically the piers are supporting the perimeter, supporting the house.  Is this normal in an older house, or something I need to get checked out? 

Here, I made a very professional drawing -- the red is dirt so I'm guessing about how far the piers go down.

(http://i.imgur.com/fcVjXYi.png)
Title: Re: What's that smell?
Post by: dragoncar on June 27, 2016, 02:02:43 PM
I know you are all completely riveted by my smell question, so I'm providing an update.  Went under the house today, and saw/smelled nothing.  I also tried running the whole house fan (exhausts through attic) with no windows open.  Checked every outlet and other penetration I could think of -- air was infiltrating but no smell (at any specific penetration or even in general).  So now I'm really stumped.  I'm leaning towards it being the gardenias we have outside the windows, but as I mentioned they do not smell that way when I'm outside.  Perhaps the smell reacts with something else once it gets inside to make it more noticeable.

I also noticed that my foundation perimeter seems not to be fully resting on the dirt.  It looks like there are piers, with perimeter between the piers.  It seems the ground has settled below the perimeter (in some locations I can see underneath the foundation).  So basically the piers are supporting the perimeter, supporting the house.  Is this normal in an older house, or something I need to get checked out? 

Here, I made a very professional drawing -- the red is dirt so I'm guessing about how far the piers go down.

(http://i.imgur.com/fcVjXYi.png)

Update -- yes, it's OK and actually preferred that there is voidspace below foundation beams

http://www.lifeofanarchitect.com/pier-and-beam-foundations-khouse-progress/
Title: Re: What's that smell?
Post by: Basenji on June 27, 2016, 02:36:45 PM
And the smell?
Title: Re: What's that smell?
Post by: sisto on June 27, 2016, 03:27:07 PM
It sounds like drains to me and possibly the stacks. I'd try something natural with enzymes to flush the drains and see if that helps.
Title: Re: What's that smell?
Post by: dragoncar on June 27, 2016, 04:42:42 PM
And the smell?

I haven't smelled the smell in a while -- maybe it's only winter/spring?  Which would point toward a moisture problem, because we definitely have the windows open all night these days due to the heat.

I wouldn't be surprised if it comes back with the rains (October)

I've also been all over the attic and the crawlspace since the last post and didn't notice anything.  There is onnneee little place I can't get to under the house cause I'm too thick.  Wondering if it's OK to dig this out until I can fit through.  I'm going to eventually want to re-insulate my ducts and I can't get to them all right now.

It sounds like drains to me and possibly the stacks. I'd try something natural with enzymes to flush the drains and see if that helps.

Could be!  I'll try this if/when it reoccurs next winter/spring.  I'm starting to be the king of necoposts, but I hate finding old threads that never get resolved (or worse "hey guys I fixed it thanks!" with no explanation)
Title: Re: What's that smell?
Post by: arebelspy on June 28, 2016, 05:57:08 PM
Could be!  I'll try this if/when it reoccurs next winter/spring.  I'm starting to be the king of necoposts, but I hate finding old threads that never get resolved (or worse "hey guys I fixed it thanks!" with no explanation)

Oh thank goodness.

I've been checking this thread--almost daily--for about four months, wondering if we'd ever get an update.

I'll make sure to turn on email alerts, and set up a Gmail filter to text me as soon as you post again!  :)

(Seriously though, I do like closed loops as well.  Moisture is so anti-climactic though.  Work on that, please.)
Title: Re: What's that smell?
Post by: dragoncar on June 28, 2016, 06:12:19 PM
Could be!  I'll try this if/when it reoccurs next winter/spring.  I'm starting to be the king of necoposts, but I hate finding old threads that never get resolved (or worse "hey guys I fixed it thanks!" with no explanation)

Oh thank goodness.

I've been checking this thread--almost daily--for about four months, wondering if we'd ever get an update.

I'll make sure to turn on email alerts, and set up a Gmail filter to text me as soon as you post again!  :)

(Seriously though, I do like closed loops as well.  Moisture is so anti-climactic though.  Work on that, please.)

Don't you hate it when you post a quick joke response and you are SUBSCRIBED FOR LIFE
Title: Re: What's that smell?
Post by: arebelspy on June 28, 2016, 08:50:10 PM
Don't you hate it when you post a quick joke response and you are SUBSCRIBED FOR LIFE

Those animated gifs get me into more trouble...
Title: Re: What's that smell?
Post by: Frankies Girl on June 28, 2016, 09:23:38 PM
What type of windows do you have? I have a house built in the early 1980s, and the windows are single pane aluminum with a rubber/plastic type of seal on the part that contacts the bottom of the frame. I've noticed that when it rains lots, the water stands in the aluminum frame, and the seals (being old) are slightly cracked and allow moisture to flow into themselves. There has been mold in many of the lower sections of the seals/frames from the standing water. I clean them out occasionally with a bleach spray, soap and a toothbrush and rags on the inside, but as I can't really mess too much with the seals, if there is any mold trapped in them, it's staying.

Just wondering if you might be smelling mold in the frames/seals of the windows themselves since they're open?
Title: Re: What's that smell?
Post by: stashgrower on June 29, 2016, 07:41:01 AM
Hmmm damp? sitting water?
Title: Re: What's that smell?
Post by: Gingerella on March 12, 2019, 02:10:01 AM
Hi,
Did you finally find out from where the smell was coming?
we smell same in the last days, both me and my husband...
Thanks..
Title: Re: What's that smell?
Post by: dragoncar on March 12, 2019, 08:56:27 AM
I finally decided it was from the azaleas or gardenias outside the window.  I must be more sensitive to the smell than others
Title: Re: What's that smell?
Post by: arebelspy on March 12, 2019, 01:07:14 PM
I finally decided it was from the azaleas or gardenias outside the window.  I must be more sensitive to the smell than others

That was ruled out in the OP:
We do have plants outside our windows, and I've stuck my nose in there many a time but I don't get the same smell (and the air around the windows doesn't smell either).

And later:
None of the house perimeter has this smell.

Back to the drawing board!
Title: Re: What's that smell?
Post by: GuitarStv on March 12, 2019, 02:17:38 PM
There is a faint musky animal smell that we get in our living room, only when it's very warm and humid outside.  I went nuts trying to get rid of it when we first bought the house.  Near as I can figure it's from a cat that peed in one of the registers and this soaked into the wood in that area where I can't reach.  It has been 9 years and has not become less smelly, so I've had to make my peace with it.

:P
Title: Re: What's that smell?out
Post by: dragoncar on March 13, 2019, 10:06:42 AM
I finally decided it was from the azaleas or gardenias outside the window.  I must be more sensitive to the smell than others

That was ruled out in the OP:
We do have plants outside our windows, and I've stuck my nose in there many a time but I don't get the same smell (and the air around the windows doesn't smell either).

And later:
None of the house perimeter has this smell.

Back to the drawing board!

True, but it seems to get concentrated indoors somehow in a way that doesn’t happen outside.  I guess planty smells come from plants.  Who knew?

¯\_(ツ)_/¯
Title: Re: What's that smell?
Post by: BudgetSlasher on March 13, 2019, 07:21:44 PM
There is a faint musky animal smell that we get in our living room, only when it's very warm and humid outside.  I went nuts trying to get rid of it when we first bought the house.  Near as I can figure it's from a cat that peed in one of the registers and this soaked into the wood in that area where I can't reach.  It has been 9 years and has not become less smelly, so I've had to make my peace with it.

:P

Have you tried ozone generators? I got a couple when we moved into our house from forever ozone and shock treated every room (a couple times). The former owners were smokers and there was definitely some "pet" in the carpet. It helped a great deal, but without AC on hot humid days the smells can come faintly come back.

Now our ozone generators tend to get loaned out to co-workers who have the unfortunate luck to have a dog get sprayed by a skunk and track it into the house.
Title: Re: What's that smell?
Post by: GuitarStv on March 14, 2019, 09:23:15 AM
There is a faint musky animal smell that we get in our living room, only when it's very warm and humid outside.  I went nuts trying to get rid of it when we first bought the house.  Near as I can figure it's from a cat that peed in one of the registers and this soaked into the wood in that area where I can't reach.  It has been 9 years and has not become less smelly, so I've had to make my peace with it.

:P

Have you tried ozone generators? I got a couple when we moved into our house from forever ozone and shock treated every room (a couple times). The former owners were smokers and there was definitely some "pet" in the carpet. It helped a great deal, but without AC on hot humid days the smells can come faintly come back.

Now our ozone generators tend to get loaned out to co-workers who have the unfortunate luck to have a dog get sprayed by a skunk and track it into the house.

I'd kinda rather smell animal than pump ozone into my home.  That stuff is not good for you.
Title: Re: What's that smell?
Post by: dragoncar on March 14, 2019, 09:38:50 AM
I used to have one of those stupid ionic breeze things and agree I don’t want to breathe ozone.

But for commercial deodorant purposes, they pump in a bunch and it dissipates quickly (because it’s highly reactive).  So you just do it when you aren’t home and give it time to dissipate
Title: Re: What's that smell?
Post by: BudgetSlasher on March 14, 2019, 05:29:33 PM
There is a faint musky animal smell that we get in our living room, only when it's very warm and humid outside.  I went nuts trying to get rid of it when we first bought the house.  Near as I can figure it's from a cat that peed in one of the registers and this soaked into the wood in that area where I can't reach.  It has been 9 years and has not become less smelly, so I've had to make my peace with it.

:P



Have you tried ozone generators? I got a couple when we moved into our house from forever ozone and shock treated every room (a couple times). The former owners were smokers and there was definitely some "pet" in the carpet. It helped a great deal, but without AC on hot humid days the smells can come faintly come back.

Now our ozone generators tend to get loaned out to co-workers who have the unfortunate luck to have a dog get sprayed by a skunk and track it into the house.

I'd kinda rather smell animal than pump ozone into my home.  That stuff is not good for you.

That's why you aren't in the home when you shock treat. Ozone is highly unstable and breaks down quickly without a source constantly generating it, and opening a window or two lets it dissipate.

That's my take on it from my research, but if you have made your peace then there is no need to do anything.
Title: Re: What's that smell?
Post by: Wrenchturner on March 16, 2019, 02:16:34 PM
What type of windows do you have? I have a house built in the early 1980s, and the windows are single pane aluminum with a rubber/plastic type of seal on the part that contacts the bottom of the frame. I've noticed that when it rains lots, the water stands in the aluminum frame, and the seals (being old) are slightly cracked and allow moisture to flow into themselves. There has been mold in many of the lower sections of the seals/frames from the standing water. I clean them out occasionally with a bleach spray, soap and a toothbrush and rags on the inside, but as I can't really mess too much with the seals, if there is any mold trapped in them, it's staying.

Just wondering if you might be smelling mold in the frames/seals of the windows themselves since they're open?
\
This is what I was thinking.  Very odd that you would get an odor forming when windows/doors are OPEN.  Usually a plumbing vent issue will show up in the opposite circumstance, when air pressure deltas can form due to thermosiphoning in the building.  It also would be pretty identifiable and localizable.  This could be a normal outdoor scent that is only discernible indoors because it's diluted outside or something.

You're gonna have to isolate variables: which window, what time of day, what's the weather like, how long does it take to show up...or consider taking up smoking to disable that bloodhound-nose of yours.
Title: Re: What's that smell?
Post by: Gerard on March 20, 2019, 03:19:39 PM
Cherry-picking a few data points here (smells like weed, stronger with windows open, stronger in winter/spring, house on piers), I'm gonna suggest it's critters. Maybe raccoons. Some weed smells like skunk, and raccoons smell like less-stinky skunks.

I guess it depends on the type of weed smell. If it smells like really good weed, probably not raccoons. If it smells like homegrown from rural Quebec in the 1970s, possibly raccoons.
Title: Re: What's that smell?
Post by: ender on March 20, 2019, 03:46:03 PM
That's why you aren't in the home when you shock treat. Ozone is highly unstable and breaks down quickly without a source constantly generating it, and opening a window or two lets it dissipate.

That's my take on it from my research, but if you have made your peace then there is no need to do anything.


Yep. This is a way people often clean out smoke smells, too. Ozone wrecks organic stuff and has a very short halflife, so it goes away super fast. Mold, smoke, etc, all get wrecked.
Title: Re: What's that smell?
Post by: Raeon on April 10, 2019, 07:53:55 PM
I got pissed off at one of my employees who smoked in one of my company trucks and ozone shocked the thing for 12 hours.  It has a very small single cab.  He whined about the ozone after-smell. (This was after letting it dissipate for 24 hours, no health danger).   I didn't know if I should laugh at him complaining about a smell after making the truck reek of cigarettes or just fire him for being an inconsiderate dolt.  I ended up doing the 1st and threatening the 2nd.  Didn't happen again. 
I love my ozone generator though. Worth every bit of the $60 it cost.  I've used it in all my work trucks.  Food, sweat, smoke, whatever odor. It fixes them all.
Title: Re: What's that smell?
Post by: dragoncar on April 10, 2019, 10:51:18 PM
I got pissed off at one of my employees who smoked in one of my company trucks and ozone shocked the thing for 12 hours.  It has a very small single cab.  He whined about the ozone after-smell. (This was after letting it dissipate for 24 hours, no health danger).   I didn't know if I should laugh at him complaining about a smell after making the truck reek of cigarettes or just fire him for being an inconsiderate dolt.  I ended up doing the 1st and threatening the 2nd.  Didn't happen again. 
I love my ozone generator though. Worth every bit of the $60 it cost.  I've used it in all my work trucks.  Food, sweat, smoke, whatever odor. It fixes them all.

Was it really the smell of ozone or is he just used to things smelling bad and a clean truck smells bad to him?
Title: Re: What's that smell?
Post by: Fishindude on April 11, 2019, 07:28:19 AM
Possibly natural gas?
Not unusual for gas meters to get a little leak.   Squirt a little water all over it and see if you are getting bubbles somewhere?
Title: Re: What's that smell?
Post by: DeniseNJ on April 11, 2019, 02:32:29 PM
What type of windows do you have? I have a house built in the early 1980s, and the windows are single pane aluminum with a rubber/plastic type of seal on the part that contacts the bottom of the frame. I've noticed that when it rains lots, the water stands in the aluminum frame, and the seals (being old) are slightly cracked and allow moisture to flow into themselves. There has been mold in many of the lower sections of the seals/frames from the standing water. I clean them out occasionally with a bleach spray, soap and a toothbrush and rags on the inside, but as I can't really mess too much with the seals, if there is any mold trapped in them, it's staying.

Just wondering if you might be smelling mold in the frames/seals of the windows themselves since they're open?

This.  If it's coming when the window is open and it's not inside and it's not outside, then I think it's the actual window frame.  The window sill is collecting water.  It might even be seeping a bit into the wall under the window.  The smell may be coming from the insulation or tubing in the window sill, as above.