airblocks underneath knee walls
 

Hello. I have a cape style home with knee walls. I have heard that I should block the airflow in the joist cavity directly beneath the knee wall. If there is insulation batting there already, should I cut the batts, fit the block, then start the batts over again? It seems I should not just squish the batts to install this air block. And, is carefully cut and calked bead board good for this purpose? Thank you.

okay, so I had to google knee walls, my sister's house has them but wasn't sure, anyway, here is nice piece on it,, hope it helps you
http://www.hgtvpro.com/hpro/bp_frami...243849,00.html

dude thanks

Answer to your question
 

Bob, did you ever get an answer to your question? The site that was mentioned was really good, but didn't address the question on how to block the floor cavity below the knee wall. I have the exact same question.
THanks

You can use rigid foam insulation and cut it so it's tight to the joists. If it's too loose, spray in some foam insulation from the cans to seal the edges.
Ron

My area behind the knee wall was actually insulated & rocked before the knee wall went up. Then the knee wall was also insulated w/R19
So equiv of R38 to R44 insulation. The knee wall area stays warmer, but that heat is kept away from the roofing
My knee wall area is also used for storage

followup question
 

Ron, I have a subfloor layed behind my kneewall that has insullation running along the floor joists. Just want to make sure I understand what I need to do. I think what your saying is that I need rip up enough of the subfloor behind the knee wall to insert rigid foam insulation. That means I will have to also cut part of the already existing insullation that runs the length of the joists to put the rigid foam in.