# can foam board be used on interior?



## Windows on Wash (Aug 30, 2011)

Drawback of this is that it will keep the framing even more cold and therefore increase the chance of condensation on them. 

Foam to the inside is not a great idea when you are talking about covering the studs.

If you want additional R-Value in that wall, cut foam board to fit inside the wall and do a layer of foam first, then the batts.


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## Fix'n it (Mar 12, 2012)

this is what i was told to do, here. seems to be working very well. i am also going to do 1" xps under new siding.


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## user1007 (Sep 23, 2009)

Check your local building/fire code. Most foam board is not fire rated and code may call for you to cover it with a certain thickness drywall. I am fairly certain you could not meet code unless the foam was inside the framing and then covered. And as mentioned, you do not want to create a moisture barrier. 

If you really want the r value, you would better off finding someone to come out and spray foam into the cavities if you can find someone willing to do a small job.


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## Gary in WA (Mar 11, 2009)

If you do "cut-n-cobble" to the cavities, use EPS rather than more expensive XPS, and it's a lot "greener" because of the blowing agent used.

1. Any OSB in the wall make-up? 

2. Where are you located?

Gary


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