Blue
November 24th, 2009, 07:29 PM
Yep, I'm doing what they call an unvented or conditioned crawl space on this room addition I'm doing right now. I had to review the code admendments for this because it is my first one and the inspectors had to look how to do it also.
I got the interior concrete walls done with 1 inch fire rated insulation panels. The floor is 2 layers of 6 mil on dirt, running up all the walls and secured with 1x6 treated pine. All joints overlap and are taped with tyvek tape.
The code says that there are three ways to vent. The one I chose is to install a tee on both ducts with a damper set to 80% closed. The code states that I must move 1 cubic foot of conditioned air per 50 cubic feet of space so that computes to 8 cubic feet per minute. I have to install a grill for return also.
If anyone has experience with this system, please review my numbers and tell me if everything looks good. I can't find aything that speaks to the size of the return grill.
I got the interior concrete walls done with 1 inch fire rated insulation panels. The floor is 2 layers of 6 mil on dirt, running up all the walls and secured with 1x6 treated pine. All joints overlap and are taped with tyvek tape.
The code says that there are three ways to vent. The one I chose is to install a tee on both ducts with a damper set to 80% closed. The code states that I must move 1 cubic foot of conditioned air per 50 cubic feet of space so that computes to 8 cubic feet per minute. I have to install a grill for return also.
If anyone has experience with this system, please review my numbers and tell me if everything looks good. I can't find aything that speaks to the size of the return grill.