spray foam and make up air

[bobbyjean]

went to a job last week to fix some unit's....big garage type structure with spray foam in ceiling,over block wall's.
there were large garage door's that seemed well insulated....so the problem
the SMELL....i mean there were only 5/6 people working in a space that had to be 15k sq. feet.... at least 16 ft ceiling open
it was nasty..a little fishy smelling....i didn't see any forced fresh air so just wondering ..is it the foam itself that would give that smell or the fact that it's so tite?

 

[Musicinabottle]

I've read before that sometimes there have been issues with the smell to the extent that homes couldn't be occupied.

 

[yeldogt]

foam should not smell

 

[kj_mustang]

Mine had a little bit of smell right after it was installed but was gone in a couple days. Lived in mine for 1.5 years with no smell, unvented attic, closed cell foamed roof and walls, no fresh air system.

 

[rlitman]

foam should not smell

Should not, and does not are two different things.
I blew cellulose into an attic space, and there was quite an ammonia smell for a few weeks. That however eventually went away.

The chemicals in urethane have their own smells. Those should go away after it is cured (within a few days at least), but I wouldn't be surprised if it smelled a bit while it was being applied. There's also often a blowing agent that can work its way out over time. But I certainly agree that over the long-term, foam shouldn't smell (though there have been cases where it was mixed improperly, where it can smell).

The most likely cause of the smell was not the foam itself, but the fact that something in the space smelled, and the foam helped seal up the space very well. Perhaps a little too well.

 

[Kaizen]

I had open cell sprayed in a few rooms and it did in fact smell where I felt the need to put a fan in the window. Smelled for a day or so. Just off gassing. If a house was closed up after spray foam I imagine it would smell longer.


Sent from my iPhone using Tapatalk

 

[yeldogt]

Should not, and does not are two different things.
I blew cellulose into an attic space, and there was quite an ammonia smell for a few weeks. That however eventually went away.

The chemicals in urethane have their own smells. Those should go away after it is cured (within a few days at least), but I wouldn't be surprised if it smelled a bit while it was being applied. There's also often a blowing agent that can work its way out over time. But I certainly agree that over the long-term, foam shouldn't smell (though there have been cases where it was mixed improperly, where it can smell).

The most likely cause of the smell was not the foam itself, but the fact that something in the space smelled, and the foam helped seal up the space very well. Perhaps a little too well.

I was not speaking ..as if it was being applied. The OP went into a space that I'm assuming was not just sprayed with 5/6 people walking around.

Have had it done many times -- no odor. I'm not around while it's being done.

 

[Fixin'Stuff]

If not mixed properly it can be dangerous. See some of the vids here: https://www.youtube.com/results?search_query=spray+foam+disasters

 

[drboom]

If the smell is foam, something isn't right.

We had closed cell spray foam in our attic a couple of years ago. There was a terrible smell of foam whenever it got hot outside. After some loud complaining on my part, the installer contacted the manufacturer who flew someone in to check it out. He found one small spot (maybe 4 inches cubed) that didn't cure correctly. He cut that spot out and the smell was resolved.

Our install was quite difficult and the team did a remarkably good job. We're pretty sure that the spray foam gun "burped" where it didn't cure.

I should note that the manufacturer stepped up and had the installer correct that spot and a few other my minor issues they found and paid for a hotel when we had to evacuate when they fixed the foam.


Sent from my iPad using Tapatalk

 

[bobbyjean]

I was not speaking ..as if it was being applied. The OP went into a space that I'm assuming was not just sprayed with 5/6 people walking around.

Have had it done many times -- no odor. I'm not around while it's being done.

yeldogt-you are correct....foam was not new...

 

[Falcon67]

If not mixed properly it can be dangerous. See some of the vids here: https://www.youtube.com/results?search_query=spray+foam+disasters

Which reminded me of some people we knew that built a house north of town. The house was spray foamed like a lot of them are. We stopped by the house to snoop and it happened to be on the day it was being sprayed. Two guys, a lady and a COUPLE OF KIDS were the "crew" and all were inside (plastic hung over exterior openings) while the foam was being sprayed. PPE - none. Except the guy shooting who had a little dust mask on. We left quickly.

 

[mrpizza]

Falcon67, good idea to leave! That foam will mess up your lungs quick while its being sprayed. Supposed to have respirators rated for the chemicals.

 

[NUTTSGT]

What were they using to heat the structure ? If they were spraying something like Brakleen in the enclosed facility and no good outside air, it would really stink when sucked into a radiant type heater.

 

[Acuratechva]

If not mixed properly it can be dangerous. See some of the vids here: https://www.youtube.com/results?search_query=spray+foam+disasters

I"ve seen this video and if i had to guess, its got to be funded by a competitor insulation company. There is no useful info there, just scare to deter people from using it.

No real info on foam origin or actual analysis other than some guy in a suit coming out to smell it....well no **** buffalo bill! any ***** can tell you that! I am shopping for spray foam now and can say that video just made things worse without adding any valuable info. Thats how i found this post.

Lots of people have mixig problems but its mainly smaller sketchy companies with no customer service like Foam it Green. I swear half their reviews are fake AF

 

[Denwood]

went to a job last week to fix some unit's....big garage type structure with spray foam in ceiling,over block wall's.
there were large garage door's that seemed well insulated....so the problem
the SMELL....i mean there were only 5/6 people working in a space that had to be 15k sq. feet.... at least 16 ft ceiling open
it was nasty..a little fishy smelling....i didn't see any forced fresh air so just wondering ..is it the foam itself that would give that smell or the fact that it's so tite?

I feel bad for those folks if they are working:

A: with no proper fire barrier between them and the foam
B: no air exchange.

I have a friend here in town who built a big, well insulated, “shop” which is used primarily for his wife’s dog training business. They designed in zero air exchange (like a basic HRV) and surprise...have a humidity/mold issue now.

 

[theoldwizard1]

Extremely "tight" structures have "air exchange" device. The warm exhaust air is used to heat the cool incoming air.

 

[dcg9381]

I've read before that sometimes there have been issues with the smell to the extent that homes couldn't be occupied.

Having lived in several buildings insulated in foam, I can say this should not be the case. Many modern homes - if "tightly insulated" may need a fresh-air intake, but they should not smell.

Foam smells for a little bit (not offensive, at least not to me) after install, but that's it..

 

[yeldogt]

I feel bad for those folks if they are working:

A: with no proper fire barrier between them and the foam
B: no air exchange.

I have a friend here in town who built a big, well insulated, “shop” which is used primarily for his wife’s dog training business. They designed in zero air exchange (like a basic HRV) and surprise...have a humidity/mold issue now.

All tight buildings need ventilation -- A properly done ZIP structure will have the same problem. My issue with ZIP .. it's not been proven (glue) and needs to be properly built --- wonder if it will hold up for 100 years? You have to have a way to bring in fresh air -- positive pressure

Fire: This is interesting because years ago there were many industrial building with exposed foam -- I was in a few seedling companies years ago done that way.

I had a major fire -- it got really going when cars went up. The fire was outside and was able to eat through the wood siding and the wood studs -- and the windows .... but it did not burn the foam. A very small area sort of melted -- but the foam stopped the fire -- even along the roof with cedar siding.

I was watching a video years ago: About the dangers of foam and fire. They took a windowless metal building and foamed the whole thing -- started a fire in the middle. I forget what the fire source was -- but it was designed to be able to keep going and increase the temp inside. The space was basically a foam box ... well, eventually the temp reached the flash over point of the foam and the building went up with dramatic results. The point being -- see the dangers of foam. Do you want this to happen to your house?

They never point out that people don't live in building w/o openings -- they never reach those temps ... and you would have been dead from smoke way before.

 

[wanderer]

When I built my house I took the spare open cell foam that was trimmed from the studs and burned it. I was shocked how fast it ignited and gave off terrible black smoke. Were talking seconds, and it was gone within a minute or so, quite flammable. I’m not convinced it would burn incredibly fast inside a wall cavity, but it disturbed me just the same.

 

[yeldogt]

When I built my house I took the spare open cell foam that was trimmed from the studs and burned it. I was shocked how fast it ignited and gave off terrible black smoke. Were talking seconds, and it was gone within a minute or so, quite flammable. I’m not convinced it would burn incredibly fast inside a wall cavity, but it disturbed me just the same.

FYI: Mine was closed .... My guess is there are different types of both.

I don't know what the fire stop foam product is made form -- or what they do to it t.. My assumption is it must not burn? I'm talking about the colored product that's used to fill holes in commercial buildings and now residential.

I have tried to burn a couple different samples of closed foam using a map gas torch -- it sort of surface melts after a while -- but does not burn.

 

[rlitman]

FYI: Mine was closed .... My guess is there are different types of both.

I don't know what the fire stop foam product is made form -- or what they do to it t.. My assumption is it must not burn? I'm talking about the colored product that's used to fill holes in commercial buildings and now residential.

I have tried to burn a couple different samples of closed foam using a map gas torch -- it sort of surface melts after a while -- but does not burn.

Well, for starters, open cell will allow air to flow through it, which can in theory help feed the flames. Anyway, not all foams are created equal.

A fire stop foam isn't necessarily unable to be burned. But it has to self-extinguish, and not drip flaming melted goo that spreads fire like napalm (which many plastics will do).

Also, remember that in a closed wall cavity, a material that burns well but extremely rich can actually help extinguish a flame by consuming all available oxygen (though smouldering isn't necessarily a safe condition either). So foam that throws off thick black smoke when burned in open air may be much safer when enclosed as per the instructions.

 

[yeldogt]

Well, for starters, open cell will allow air to flow through it, which can in theory help feed the flames. Anyway, not all foams are created equal.

A fire stop foam isn't necessarily unable to be burned. But it has to self-extinguish, and not drip flaming melted goo that spreads fire like napalm (which many plastics will do).

Also, remember that in a closed wall cavity, a material that burns well but extremely rich can actually help extinguish a flame by consuming all available oxygen (though smouldering isn't necessarily a safe condition either). So foam that throws off thick black smoke when burned in open air may be much safer when enclosed as per the instructions.

Fire needs a pathway .... w/o a pathway the fire can't grow. I saw this first hand with my fire. As the fire was able to consume something flammable it moved. When it hit the foam .. stopped ......unless the flames were large enough to jump the foam and consume something else. The fire was consuming one side of the wall and the other had no smoke coming through.

Most people die from the smoke -- getting more time to get out is why I was impressed.