What is the smartest way to insulate a finished attic?
Hi. I am a newby on this site and am looking for advice on how to correctly insulate the living space in my attic.
I believe in a vented roof so I vented the rafter bays with 1" Dow Tuff R rigid insulation spaced 2" off the underside of the roof sheathing. It is sealed all the way down to the floor and it ends about 6 inches above the collar ties. I sealed all the edges with foam and I taped all the seams.
The rafters are 2x10 and the collar ties are 2x8. I live in northern New Jersey in IECC zone 4. The rigid insulation is R6.5.
I have space in the ceiling for R38 fiberglass batts but I am not sure what I should do with the slanted sections of the roof that will have sheet rock attached to it. Having used the rigid insulation to create my vent chutes, I am not sure how this affects what kind of vapor barrier(or retarder) I should use.
I am planning to insulate the knee walls for added R value. What am I doing right, what am I doing wrong and what am I supposed to do?
Thanks for your help.
Posted May 7, 2012 3:54 PM ET
Edited May 8, 2012 6:13 AM ET
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