Q&A Forums

foam in rafter question Post New Topic | Post Reply

Author Comments
Ben Jaeger
Posted: Sep 14, 2010 12:10 AM
foam in rafter question
Mason,
I have a job Im bidding on its an older 2-story home completely gutted. My question has to do with the roof venting.

In the second story the customer wants me to spray 3"cc on a 4' high knee wall and 5"cc in a 2"x6" ceiling rafter from the knee wall up to the peak. He is then planning on doing a dry blown attic insulation on the attic floor behind the knee walls.

With this setup do I have to install vent chutes or is there a way he can do an unvented roof system?

If I install the chutes up to the peak, how do you seal everything up top with out the conditioned air leaking out?
mason
Posted: Sep 15, 2010 08:31 AM
The cellulose insulation behind the kneewalls would need to vented, but not the sprayfoam area. Just keep those two areas sealed and separated from each other.

You need to login to reply to this topic. Please click here to login.