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BOB ROBERTS Posted: Jan 15, 2014 10:07 AM	foam and cellulose combination in the attic, HELP! My attic was sprayed with foam to make it a conditioned space. My ductwork and plenum are in the attic also. However, the foam contractor did not do a great job, and the foam off-gasses when its hot outside and the roofline gets hot. This is causing an issue with odors in my home and with my son's and mom's respiratory issues. . My question is, can I remove the foam from my gable, soffit, and roof vents, to allow fresh air to move through it and pull those gasses out of my attic (like a traditional attic) , but get cellulose sprayed on the attic floor to keep my home's interior insualted? In other words, the just roofline will still have foam on it creating a semi-conditioned space, but the attic floor will be covered in cellulouse to keep the home insulated.This will allow fresh air to move through the attic to help remove the gasses. I've gotten different opinions about this from different people, concerning possible pressure issues or mold issues, etc. so I don't know if it is possible or not. The issue is that my son had severe asthma and I can't have those gasses getting into my home.
Mark Mouton Posted: Jan 21, 2014 12:19 PM	How long ago was it installed? It would help to know what brand of foam it is, and is it open or closed cell?
BOB ROBERTS Posted: Jan 23, 2014 09:25 AM	Thanks man. It was installed back in June of 2013. It is open-cell. The product they supposedly used is Thermoseal 500.
Mark Mouton Posted: Jan 23, 2014 10:37 PM	It seems kind of a waste to say this, but you can install blown cellulose in the attic. The way I would set it up is, install a solar powered attic exhaust fan in the center of the rear of your roof, preferably on the south side. (There is a proper way to set one up). Then open up about 4 holes to the soffit on the back of the house, then 4 on the front. Don't open up the entire area to the soffit. Open it at the corners and then split it up in the centers. You want to try and match the number of openings with the CFM's of the fan so you are pulling air from the farthest points. Then blow the attic insulation last. Atticbreeze.com makes a good high quality fan. Tip#1: If you use the atticbreeze, cut a 20" opening, not smaller. Tip#2; Be sure the solar panel faces south on a 22-45 degree angle. Also, maybe somebody else will read this and have a better idea how you can fix the foam. If you can keep an unvented attic, you will be better off. It seems like it should stop off-gassing after a while.
BOB ROBERTS Posted: Jan 24, 2014 08:01 AM	Thanks! What about the gable vents, I have one on each side? Should I open them? My house has 2 gable vents, 8 soffit vents and 2 regular roof vents, plus the power vent. Right now, everything is sealed except the power vent.
Mark Mouton Posted: Jan 24, 2014 06:53 PM	I would go with just the power vent right now, pulling from the 6-8 openings made to the soffits to pull the smell out of the attic. You may have just 8 vents in the soffits, but it is like a trunkline so you can open the attic to it anywhere and it will get outside air. It might get to a place where there is no more odor, which it probably will, and then you can seal it back like it should be, so I wouldn't just open everything up.

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BOB ROBERTS

Posted: Jan 15, 2014 10:07 AM

foam and cellulose combination in the attic, HELP!

My attic was sprayed with foam to make it a conditioned space. My ductwork and plenum are in the attic also. However, the foam contractor did not do a great job, and the foam off-gasses when its hot outside and the roofline gets hot. This is causing an issue with odors in my home and with my son's and mom's respiratory issues.

.
My question is, can I remove the foam from my gable, soffit, and roof vents, to allow fresh air to move through it and pull those gasses out of my attic (like a traditional attic) , but get cellulose sprayed on the attic floor to keep my home's interior insualted? In other words, the just roofline will still have foam on it creating a semi-conditioned space, but the attic floor will be covered in cellulouse to keep the home insulated.This will allow fresh air to move through the attic to help remove the gasses. I've gotten different opinions about this from different people, concerning possible pressure issues or mold issues, etc. so I don't know if it is possible or not. The issue is that my son had severe asthma and I can't have those gasses getting into my home.

Mark Mouton

Posted: Jan 21, 2014 12:19 PM

How long ago was it installed? It would help to know what brand of foam it is, and is it open or closed cell?

BOB ROBERTS

Posted: Jan 23, 2014 09:25 AM

Thanks man. It was installed back in June of 2013. It is open-cell. The product they supposedly used is Thermoseal 500.

Mark Mouton

Posted: Jan 23, 2014 10:37 PM

It seems kind of a waste to say this, but you can install blown cellulose in the attic. The way I would set it up is, install a solar powered attic exhaust fan in the center of the rear of your roof, preferably on the south side. (There is a proper way to set one up). Then open up about 4 holes to the soffit on the back of the house, then 4 on the front. Don't open up the entire area to the soffit. Open it at the corners and then split it up in the centers. You want to try and match the number of openings with the CFM's of the fan so you are pulling air from the farthest points. Then blow the attic insulation last.
Atticbreeze.com makes a good high quality fan.
Tip#1: If you use the atticbreeze, cut a 20" opening, not smaller.
Tip#2; Be sure the solar panel faces south on a 22-45 degree angle.
Also, maybe somebody else will read this and have a better idea how you can fix the foam. If you can keep an unvented attic, you will be better off. It seems like it should stop off-gassing after a while.

BOB ROBERTS

Posted: Jan 24, 2014 08:01 AM

Thanks!

What about the gable vents, I have one on each side? Should I open them?
My house has 2 gable vents, 8 soffit vents and 2 regular roof vents, plus the power vent. Right now, everything is sealed except the power vent.

Mark Mouton

Posted: Jan 24, 2014 06:53 PM

I would go with just the power vent right now, pulling from the 6-8 openings made to the soffits to pull the smell out of the attic.
You may have just 8 vents in the soffits, but it is like a trunkline so you can open the attic to it anywhere and it will get outside air.
It might get to a place where there is no more odor, which it probably will, and then you can seal it back like it should be, so I wouldn't just open everything up.

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