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dellphinus
Existing Foam "loose", and unaccessable crawl

Greetings,
We have an older (1890-1900) two story farm house. At some point in its past, foam insulation was injected into the exterior walls (the plugs are plastic, if that helps date it). The foam is "loose" in the walls- we get a lot of air infiltration around electrical boxes. Short of pulling down the lathe and plaster, and removing/redoing the foam, is there any other remedy? I can seal all the wall penetrations, but if there's that much air getting around the foam, I have to questions it's effectiveness anyway.

Second question- a portion of the kitchen (an add on, I believe) sits over a completely sealed area- I have no idea how deep it is. The foundation is concrete block. The floor over this area gets very cold. I have been contemplating knocking a hole or two in the blocks to gain access, and having the area filled with foam, if it's not too deep, or seeing if a contractor could get a long gun in to spray the walls and floor from below if it's too deep to completely fill. Thoughts/comments/suggestions?

Thanks!
DP

Shubi
Re: Existing Foam "loose", and unaccessable crawl

Ineffective foam insulation is a real problem. I've tried to run a sidewall tube through the stuff to add cellulose, but ended up writing off additional insulation, since the tube could not be fed through and packed with foam trying to do so. Older style foam is like a sponge, allowing air to pass right through, which I'm sure you're aware of by now. Removal may be the only option and start over. Sealing wall penetrations would help, but if you ran a blower door test on your home, you would probably find air being pulled from just about everywhere as I have seen.

As far as the crawl under the kitchen, I would install an access in the block. Be careful of method of insulation, since you may have water and / or electric lines there. I would probably lay a vapor barrier of 6 mil poly on the floor of the crawl, and insulate the perimeter in this case. Spray foam could be used, or R-11 duct wrap if the area is dry enough.

dellphinus wrote:

Greetings,
We have an older (1890-1900) two story farm house. At some point in its past, foam insulation was injected into the exterior walls (the plugs are plastic, if that helps date it). The foam is "loose" in the walls- we get a lot of air infiltration around electrical boxes. Short of pulling down the lathe and plaster, and removing/redoing the foam, is there any other remedy? I can seal all the wall penetrations, but if there's that much air getting around the foam, I have to questions it's effectiveness anyway.

Second question- a portion of the kitchen (an add on, I believe) sits over a completely sealed area- I have no idea how deep it is. The foundation is concrete block. The floor over this area gets very cold. I have been contemplating knocking a hole or two in the blocks to gain access, and having the area filled with foam, if it's not too deep, or seeing if a contractor could get a long gun in to spray the walls and floor from below if it's too deep to completely fill. Thoughts/comments/suggestions?

Thanks!
DP

foammaster
Re: Existing Foam "loose", and unaccessable crawl

old injection foam usally is in Ineffective. low R-value, Formaldehyde (Amino-plast) and carelessness by the installer. you might try to find out who foamed it and when, they should have a warranty. Depending on how much the foam shrunk, more foam could be injected around it. it would have to be done with more holes per cavity but would save the hassle, money, and time of removing the plaster.

injectionfoam.com

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