Lingering latex chemic smell from foam
Hello. I previously posted about needing to fix my cathedral ceiling insulation and my attic sheathing insulation (retrofit situation). I was hesitant about using spray foam but after reviewing all the options with an architect we determined for my situation spray foam was best. I researched foams and went with one marketed as “ low voc” which I realize is just marketing.
For my cathedral ceiling we did 3 inches of closed cell and followed by batt insulation for the rest. I waited 48 hours before installing the batts.
For the attic rafters we did 3 inches for closed cell and 7 of open cell. On the attic walls I did 3 inches closed cell .
I have 3 ervs running in the home including a dedicated one for the bedroom with the new foam as well as Charcoal hepa fans running. I recently also installed an exhaust for the attic at 100cfm. I have a dehumidifier running in attic as well. I also have 2 air supplies from main living space
It’s been a month and I can’t sleep in the room. It smells strong of latex painty smell. I’m positive it’s the foam because the attic smells the same but even worse. Unfortunately I did a few other small areas which smell the same. The installer assured me there would be no smell after 24 hours. It’s been 95 and humid in ny so I’m sure it amplifies things. The installer came back and agrees it smells but says it will go away with time. I’m obviously scared I’ve ruined the home.
I understand from previous readings that either 1) the foam install is bad or 2) that there was not adequate ventilation during the install. What kind of professional can assess this and do you know of any in NY. If the answer is poor ventilation during install is this something that will go away with time? I’ve heard of “baking” the smelly spaces to speed up the off gassing but not sure if the consequences of that. In the meantime I’m waiting on a TVOC air sample I did and I reached out the the manufacture for help as well. I know this stuff is impossible to remove. I appreciate all the help I can get here. Please no judgements about using foam and choosing the installer. I obviously regret it. Thank you
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100 CFM is a very small amount of airflow. A typical box fan will deliver thousands of CFM. What to need to speed up the offgassing process is a LOT of airflow to keep the concentration of “smelly stuff” in the air in the enclosed space as low as possible. Offgassing works with concentration gradients, so the lower the concentration of “smelly stuff” in the air, the faster the process will progress.
My recommendation is always to establish a large amount of cross flow ventilation, which means “air in at one end and out the other”, which helps to avoid dead spots. Run a box fan exhausting air (blowing out towards the outdoors) at one end of the space, and let air come in at the opposite end. This will depressurization the space, which will help keep the smell from leaking out into other areas.
Most of the smell is usually gone in 48-96 hours or so. Expecting it to be completely gone in 24 hours is overly optimistic. I’ve seen it take a week or two to really go down to low levels (think “it still smells like new car”, but not “this stuff stinks”). High humidity levels also slow things down in terms of the smell getting better.
Try running large amounts of ventilation in a cross flow configuration, and run that for at least several days. See if the smell is better. If the smell is better, close things up and wait a day or two and see if the smell gets worse. If it does get worse, repeat the process. If you have to repeat this process more than 3-4 times and don’t see any real improvement, then you may have a bad install. Note that bad installs are rare when using experienced installers, so you’ll probably be able to “fix” things just with extra ventilation for a while. Note that you need to ventilate with outside air, do not try to filter out the “smelly stuff” instead while keeping the space closed off from the outdoors.
Bill
Thanks Bill. My bedroom is already closed up
With Sheetrock etc. it’s a finished space now. Do you think I need to remove it all? I should remove the recessed lights but not sure that will be enough.
Re installer - I was trying to use the the low voc product and called the distributor and asked who uses it. There was only one person. He’s only been doing it for 3 years but says his main installer has been doing it for 18 years. Hopefully he was experienced as he says. This is the closed cell.
The tricky part with the installs is getting a nice, smooth and even layer of finished foam. Your installer looks to have done a good job from what I can visually see here, which makes me think that yes, they're probably an experienced crew. New installers usually have a more "lumpy" look to their finished material, often with significant variations in applied material thickness over the area of the wall. Your installation looks very even, and doesn't appear to have had much, if any, need for trimming, so that shows an experienced crew that did a good job.
Drywall WILL slow the offgassing process. Ideally, you want to have the crossflow ventilation in place for several days before closing things up, but it will still help now. I'd try that first before ripping anything open.
Bill
Thanks Bill. The open cell is obviously lumpier. See pic. Does this still look ok?
Coloration looks OK and even, so it probably cured fine. Normally open cell is overfilled and trimmed flush with the edge of the studs though, leaving a very flat surface and a 100% fill between the studs. It looks like your installer underfilled to avoid the trimming step, which they really shouldn't have done with open cell foam. Standard practice for open cell spray foam is to overfill and trim flush and flat for a 100% fill. Closed cell is usually underfilled to avoid trimming, because closed cell spray foam is much more rigid and difficult to trim.
Bill
Did they paint the exposed SF with fire retardant? That stuff really stunk up my place for a bit.
Thankfully no
In most cases, with enough time and ventilation the odor usually goes away. In a few cases the foam just doesn't cure and needs to be remediated. That happened to a friend of mine with a brand new $2M home. Not that it helps you, but for anyone considering foam, I avoid using it when possible, in part due to how often things like this happen.
That’s horrible. Yea I wish I choose other options. I’m hopefully it will go away but this is really stressful. I would have rather the heat and air loss at this point.
You can do just fine air sealing without spray foam, I usually just say "air seal the old fashioned way, with canned foam and caulk". Spray foam is a brute force way to air seal, and not necassary if you take some care with your air sealing details.
While I disagree with Michael that spray foam installs go bad often (I've seen many proper installs, not many problems), I do agree that using spray foam everywhere really isn't necassary or desireable. There are almost always other ways to do a good job, often at lower cost.
My own standard practice is to insulate walls with mineral wool batts, interior side smart vapor retarder (usually MemBrain because it's relatively inexpensive), and exterior rigid foam. Loose fill (blown) cellulose for attics. I like to air seal with canned foam and polyurethane sealant. I only use spray foam in a few niche locations where it's really the best or only option, such as unvented cathedral ceilings, rim joists (sometimes, there are other options here depending on how the home was built), and rough (cut stone) basement walls, which I've not myself ever had to deal with. Spray foam in walls is generally an extra cost that gains little or nothing. In my own home, I spray foamed only one small wall, and that was only because I had my spray foam crew here to do an unvented catherdral ceiling.
Bill
I guess it depends how often you consider "often." From personal experience and paying close attention to reports such as those posted here frequently, I would guess that somewhere between one in 100 and 500 jobs goes bad, probably on the lower end but it's not like spray foam companies openly report on problems. I've talked with others who estimate about the same. 1:100 to 1:500 odds aren't terrible, but like Russian Roulette, when it goes bad, it can be really bad.
I'd estimate maybe to the lower end of that range too, maybe out around 1:1000. I think the key is having an experienced crew though, you do NOT want to be the job a brand new crew is doing while learning to operate their rig for the first time. I've never had a problem with my usual crew, aside from the standard dribbles of foam bits glued to something we forgot to pull out of the work area, but I can't really blame the crew for that :-)
I do think it doesn't make sense to use spray foam as the primary insulating material though. I see it offered as an "upgrade" frequently, and I don't think that's a good way to go. Most people would be better off with a crew that is diligent about air sealing, then insulate with batts and loose fill. People seem to think spray foam is magical and the best performing material out there, so people have been sucked in by the marketing I think, unfortunately.
Bill
"it's not like spray foam companies openly report on problems."
It's not like customers with successful installs are likely to go on a forum and talk about their insulation either.
Thedman07, I would love to have more accurate numbers, but mine are not pulled from thin air--they are a reasonably educated guess. Personally I think the number is probably around 1:100 and 1:200, but even if Bill is right and it's 1:1000, that's within one order of magnitude.
Even at 1:1000 odds, I would not choose spray foam unless it was the only product that could reasonably do the job.
thedman07,
True, but stepping back a bit, can you think of another product or building process, which even if the problems occur quite rarely, causes the type of irremediable problems spray foam can?
Thanks for all the info. So you always use rigid board on exterior of house? In ny is that overkill if you are air sealing, using r-21 and above and an air /variable perm vapor barrier? When you say blown in you mean on the attic floor right? So you leave attic venting? Where I live almost all house w central air have equipment in attic. Would you be ok with that being exposed to elements?
Yes, I am a big fan of exterior rigid foam, and more than the amounts shown on the tables on this site, too. Coincidentally, I'm making a trip to pick up a load of polyiso tomorrow for a new project. Anyway, rigid foam helps with thermal bridging, and it makes for a more robust wall assembly when used properly. It is NOT the only way to get a high-perfoming wall, it's just my own preferred way.
Yes, "blown in" insulation in this case means on the attic floor, with a vented attic. This is usually the cheapest and most robust way to go for an attic. I would never put mechanicals in the attic, I would put them in a basement (preferred), or a ground-floor mechanical room (next best option). Mechanicals in the attic are much harder to maintain, and really beg for a conditioned attic, which adds cost and complexity to any project. It is possible to put the mechanicals in a vented attic, but that usually leads to problems down the road, and a less efficient system too when it's operating.
Bill
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Did your friend have closed cell? If so I’d love to hear what’s involved to remove it properly. I don’t want to make things worse obviously. Thank you
Thank you. Good luck with you Polyiso pickup! And pray for me this foam smell goes away:-)
My combination of CC, OC and fire retardant paint smells went away in about a week or two. I made sure to open the windows every day. Drywall went up last week and now it just smells like sheetrock.
It was rainy while we loaded, so I got soaked, but otherwise things went well and the material is now sitting here waiting to be installed.
You'll probably need more time to get the smell out than it would take if it had been ventilated while the spray foam was still exposed (i.e. not drywalled over yet). It'll take longer now, because you can't ventilate it as well. This is all about concentrations of "smelly stuff" in the air, so if there is an air barrier in the way, like drywall, the concentration of "smelly stuff" in the enclosed wall will be higher, making it take longer for the spray foam offgassing process to complete. Think of this as the difference between drying a wet towel on a clothes line, and then trying to dry that wet towel inside of a bag -- it'll take a lot longer to dry while inside the bag (but it will eventually dry out, assuming the "bag" is permeable).
Get some fans running and circulate large volumes of outside air throughout the smelly areas, that's about the best you can do. I do think you have a good chance of getting this under control though, but it might take a while (several weeks possibly).
Bill
Thanks Bill. You’re making me feel hopeful. It’s been so nasty and humid /raining so it’s been touch to ventilate but going to get aggressive about it. If it doesn’t go away I’ve heard about burning off the voc with high heat for a few days with intermittent venting but not sure the implications that has on surrounding building materials etc
After 10 days of aggressive ventilation we are back where we started. I am waiting on voc testing. At this point I’m contemplating options. I know removing can be a massive tasks. I have been exploring voc blocking paints and foils that block vocs as an alternative. It’s funny in London there is a spray foam removal service on every block as banks won’t give mortgages if you have it. Here nothing!
I have serious doubts a paint will work. You’re trying to block solvents, and those solvents can usually get through most non-hermetic materials. Aluminum foil would work though, but would be difficult to handle. Sheets of 1/2” polyiso with foil facers might be a workable option though.
Try taking a few core samples in various locations to see if you have improper curing. That would be the most likely explanation for ongoing problems with stink.
Bill
The crazy thing is the curing seems totally fine. Even had someone come check the foam. I used a foam that claims to be green guard gold certified for the low VOCs. I just got back voc testing and it’s very high especially for chemicals specific to foam (Tetrahydrofuran) I really can’t imagine how many homes are toxic from this stuff. Is there a way to remove closed cell foam? I was looking at removing by hand followed by ice blasting. I did the test at 3 weeks post and will do again at 8 weeks post but I’m guessing cooler weather will make it better for now. Thanks again for the help.
Hi Bill. Do I face the foil in or out?