Non-VOC odors from insulation?
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Our house has had a sickly sweet odor in it ever since we had spray foam insulation (which didn’t cure properly) installed along with adjacent blow-in fiber. The odor remains even after the foam and blow-in was removed (though from what I now understand, some residue was left behind and may well remain chemically active).
Several other people – including an IAQ expert – have observed this smell…with descriptions ranging anywhere from being like plastic or cotton candy or even antifreeze…all things no one would have said our house smelled like before this…so we know we’re not imagining it. And it’s so significant that we began experiencing health issues almost immediately and that still prevent us from reoccupying our home.
Yet two handheld meters did not detect unusual amounts of VOCs (one meter detected none; the other, small amounts). Active carbon air filters say the air quality is “Good” and do not do anything with the odor except possibly distribute it more widely throughout the house.
In my research on the “sweet” odor that others experience from SPF, I only see reference to it coming from VOCs. So my question is: Can such odors come from non-VOC sources?
Again, we know the odor is there; others have detected it; and we haven’t detected this odor in anyone else’s house or in stores we’ve been in. I know all homes have VOCs to some extent…but the strong, sweet smell in our home is only in our home…and on clothing worn into the house.
Vinegar seems fairly good at masking the smell, esp in rooms behind closed doors…but take the vinegar away and open the doors again, and the odor comes right back.
So something’s causing it…but if not VOCs, then what category of inhalants could this be?
Thanks in advance.
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Replies
Do you have any of the pink batts now that the other insulation has been removed? If you do some googling, you will find examples of people noting an odor that has been compared to cotton candy or caramel from some of those products. (I think specifically the Owens Corning EcoTouch brand.) Some of these stories are quite old but I got my hands on the product about two years ago and noticed it very clearly. Perhaps try to get to a local hardware supply store that has that in stock to see if it lines up with what you are smelling.
Thanks for your reply. The original fiber batts - which the contractors failed to remove before putting their stuff over them - are still there. But they never gave off that odor before. If anything we've been told the old batts would have absorbed odor from the new insulation that is now, mostly, removed.
We did have dense-pack OC put into some areas, but I contacted OC and they say they don't have reports of non-batt product giving off this odor. (And if it was, I'd suspect our garage would smell of it, yet the odor isn't there.)
So I think now, since we know there's something in the air but very unlikely to be VOCs, it must be non-volatile in nature and we need to determine what it is to test for.
Have you been able to determine any relationship to HVAC? E.g. if you turn off all ventilation (including ERV/HRV) for a few days with everything closed, is it worse? If you run the system at max ventilation for a day is it better or worse or the same? Do you have any easy way to get a whiff off the inside of the walls (e.g. through electrical junction boxes?) Is there any difference between various spaces in the house or attic or crawlspace? Do you have any cut-off building materials (particular stuff like carpets) that you could isolate in airtight Tupperware containers for a few days?
One crazy thought: Some drywallers like to put dish soap in their mud to make it smoother. Is there any chance someone put a very fragrant dish soap in the mud mix? Could you cut out a section of drywall (a section with a taped seam) and put it in an airtight container for a few days to see if it develops a scent?
Obviously with the airtight container tests, you want to get the container and yourself out of the house for a long time and then open it up in a location with a neutral smell before opening it up for a sniff.
Have you performed a full inspection of the entire house including the hard-to-access spaces? Some lubricants have a sweet smell (e.g. Muc Off bike chain lube) and it's a possibility that a tradesperson knocked over an entire container of lube somewhere and didn't think much of it after dabbing up a majority of the spill.
I personally wouldn't put too much weight on VOC readings at this point. At the end of the day, something is smelling and you are keen to find the source.
For example:
"Xylene, another sweet-smelling VOC commonly found in new cars and fossil fuels, has an odour detectable at around 0.08 ppm according to PubMed (5), but it can persist for months in certain conditions."
https://foobot.io/guides/do-volatile-organic-compounds-smell.php
Will your VOC meter pick up xylene at 0.08 ppm?
Thank you again for this info. Going through your points:
No relationship to HVAC. Multiple attempts to air out the entire house have been unsuccessful.
No evidence that anything was knocked over. House was clean and had no odor prior to installation of this insulation.
DIY smell tests recommended to us by taping paper towels to various surfaces under alum foil did not yield an obvious surface source. But we do know at least some active residue from foam remains in house.
You're correct: something is smelling and you are keen to find the source. It's not helpful when a test doesn't detect a VOC issue and air purifiers neither detect it nor combat it. So I'm trying to determine what the smell *is* as it would also help us document exactly what the contractor introduced into the air of our home...and might steer us toward a way to combat the smell.
Honestly, you need to contact a lawyer and the company needs to pay for your full tear down and rebuild.
You bought foam insulation. You did not purchase a smell. By ripping out, the company has already admitted fault.
There will never be a detective solution to your problem. The more you delay detective this legal issue, the more cost you are incurring.
A company damaged your largest life investment. Don't seek guidance on an internet forum. The company carries insurance for this very reason, to cover damages they create. They damaged you. Time to sue. That's not aggressive, that's the solution.
Ah I see your other thread now. Agree with others that it sounds like it's time for a legal professional and trying to solve this by nose is challenging and maybe unhealthy given the materials involved. I'm not a lawyer, I don't know what your contract looked like, and I don't know the law in your area...but my general understanding is that contractors will carry insurance but it only kicks in if you sue them. Do you have any insurance that may have covered you? If yes, then your insurance provider would sue the contractor and their insurance provider would then indemnify them and basically the two insurance companies would just figure it out.
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I think you are smelling isocyanate compounds: https://www.toolboxtopics.com/Isocyanates_-_A_Sweet_Smelling_Hazard.htm#:~:text=Common%20compounds%20are%20TDI%20(Toluene,require%20your%20attention%20and%20respect.. Trust your nose more than electronic equipment. I agree with Ryan; this isn't something to mess around with, get a lawyer involved ASAP.
A consultant feels one section would have been giving off isocyanates while another section is still emitting polyols. Consultant thinks it's the polyols that remain in air but I'm not certain iso can be ruled out. That said, it's hard to do legal path when contractor points to VOC testing already done. Am exploring legal avenue but that path is easier with confirmation of *what* the odor is. Also would make it easier to zero in on remediation technique. An IAQ expert did recommend further testing but if it would just be testing for same VOCs after insignificant findings for same, I don't have the time and money for it. So while we are exploring all options including legal, I feel the need to educate myself as much as possible.
If you haven't already, I recommend contacting Henri Fennell: https://polyurethanefoamconsulting.com/. He sees hundreds of problematic installations every year and might be able to save you some time and money. We'll have him on The BS*+Beer Show sometime this year but don't have a date yet.
Thank you very much. I'd actually come across his web site during my (many, many hours of) research but I thought their location in eastern VT would make it infeasible. But now that you've recommended him, I'll look into this again.
Most "sniffer" meters only detect certain types of compounds, so they will show low readings as long as the stuff they are looking for is absent. That doesn't mean OTHER stuff the meter DOESN'T recognize may well be present. I'd normally be suspect if only YOU were smelling things, but since you've had several other third parties who have also noted the smell, then that rules out any issues with you smelling something that might not be there (noses aren't always reliable :-). I'd say that since you have had other people smell it to, then you DO have an issue here.
I agree with Michael that you're probably smelling isocynates, which are the primary building blocks of the spray foam material. You can become sensitized to these over time (basically an acquired allergy). I also agree with the other posters that it might be time for a lawyer. I'd probably try the contractor's insurance company first and see about filing a claim, which MIGHT be easier/cheaper than dealing with a lawyer, but some insurance companies are easier to work with than others.
Ideally, you want to remove ALL of the problem material. You may find that the smell has been absorbed into other materials too (drywall is notorious here), which means that would need to be replaced too. Chances are you won't be able to completely remove every last bit, so you'll probably end up encapsulating some small amount that can't be removed. There are primers like BIN that can help with this, but the best is a metallic barrier. Sometimes this can be taped foil-faced polyiso, but metalized plastic films (such as that used to make Reflectix) can also work. The metal foils are about the only 100% reliable way to block volatile solvents if you have to encapsulate an area, but keep in mind that these materials are also vapor barriers, so all the usual rules about using vapor barriers in construction assemblies apply too.
Bill
Thanks, Bill. On the subjects of drywall, the walls of living spaces are painted sheetrock. So I've been trying to research if such chemical odor would simply "get on" these walls...in which case, we might hire a green cleaner to clean them...or if these chemicals can get through the paint and be absorbed into the walls...in which case, I'm not sure how that would be tackled. (I've been looking into encapsulation but have been told and have read that this can just replace chemicals with more chemicals, even with supposed "low" or "no VOC" sealants.)
We're exploring all routes (legal, insurance, etc.), but I also have doubts that we would be compensated anytime soon, and so I'm also researching everything we can do on our end for remediation. It's not a situation like some people's where they have this stuff put everywhere, into walls and in the rafters, etc. So we're exploring all ways to remediate and/or be compensated for the damage and loss, with remediation being our prime goal right now.
Everything is a "chemical", even water. There is even a web site to point fun at this fact -- the "dihydrogen monoxide" site (https://www.dhmo.org/), which is talking about water -- H2O -- but calling it a chemical type name. Don't get overly hung up on "chemicals".
Encapsulants can work, but are not as good as removing the material to begin with. The problem is that you might not have any choice. BIN is a good primer for sealing many stinky things (I've never tried using it for messed up spray foam jobs though), but it will be stinky itself for a while. BIN stink does go away relatively quickly though, and once it's done, it might seal things for you.
Using any type of metalized barrier avoids the use of any other coatings though, so there is no risk of offgassing if you use a metalized poly barrier to seal off a trouble spot. The downside is that those barriers are also vapor barriers, so you could potentially create moisture problems within your walls if you go this route.
Bill