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Jeff Maxwell Posted: Jul 04, 2007 01:51 PM	Confused homeowner Hi all, I’m a homeowner planing to have my vented attic converted into an unvented attic using cc foam. I have a couple of concerns with installation as my attic is not conventional. It has a knee wall that raises the roof above the top plate approx. 16". And also it has a porch across the front, in the center of the porch there is a high ceiling room that goes to within a foot of the rafters leaving the sides open to the porch about 14' on each side. Would it be worth foaming the roof deck over the porch and foaming the porch ceiling witch is 1x4 at 12" centers under the joist and vinyl soffit. I hate to lose access to the space above the porch. It is a hip roof 8/12 pitch with about 48 sq. of asphalt shingles in the New Orleans area. I plan on doing the prep work myself in hopes of having it done right. The only person that I know that had their home done used icynine(?). but I’m worried about moisture and mold in this area and planed to go cc. How thick should I go with and also do I have to remove my R30 fiberglass insulation from the ceiling? Sorry so long but I’m trying to gather as much info. as possible. Any suggestions would be greatly appreciated. Thanks Jeff
Brian Mulder Posted: Jul 06, 2007 06:47 PM	Jeff, Draw a very simple profile of the frame work of your house. Both the interior walls and the exterior stuff you talk about. Once this is done take a highlighter and draw a colored line for all areas where you want to keep the conditioned air in and the exterior air out. That is where you need to foam. The highlighter lines have to be solid from the bottom of one side and up and over and down to the bottom of the other side. If any space is outside leave it there. Closed cell foam is the best but is not inexpensive so install it wisely. Good luck. Brian

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Comments

Jeff Maxwell

Posted: Jul 04, 2007 01:51 PM

Confused homeowner

Hi all, I’m a homeowner planing to have my vented attic converted into an unvented attic using cc foam. I have a couple of concerns with installation as my attic is not
conventional. It has a knee wall that raises the roof above the top plate approx. 16". And also it has a porch across the front, in the center of the porch there is a high ceiling room that goes to within a foot of the rafters leaving the sides
open to the porch about 14' on each side. Would it be worth foaming the roof deck over the porch and foaming the porch ceiling witch is 1x4 at 12" centers under the joist and vinyl soffit. I hate to lose access to the space above the porch.
It is a hip roof 8/12 pitch with about 48 sq. of asphalt shingles in the New Orleans area. I plan on doing the prep work myself
in hopes of having it done right. The only person that I know that had their home done used icynine(?). but I’m worried about moisture and mold in this area and planed to go cc. How thick should I go with and also do I have to remove my R30 fiberglass insulation from the ceiling?
Sorry so long but I’m trying to gather as much info. as possible. Any suggestions would be greatly appreciated.
Thanks Jeff

Brian Mulder

Posted: Jul 06, 2007 06:47 PM

Jeff, Draw a very simple profile of the frame work of your house. Both the interior walls and the exterior stuff you talk about. Once this is done take a highlighter and draw a colored line for all areas where you want to keep the conditioned air in and the exterior air out. That is where you need to foam.

The highlighter lines have to be solid from the bottom of one side and up and over and down to the bottom of the other side. If any space is outside leave it there. Closed cell foam is the best but is not inexpensive so install it wisely.

Good luck. Brian

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