Happy New Year everyone! I came across a concern that I am not sure how to address. The home is located in Atlanta. It is a new construction ranch that has a roof pitch of 8 and has a ridge vent that spans the structure from the front to the rear. The right-hand side of the house has an open attic equipped with blown-in insulation. It also has a soffit vents and of course a ridge vent. The left-hand side of the home has a vaulted ceiling and is equipped with spray foam insulation between the roof sheathing and the sheet rock ceiling surface. At the time of the inspection, it was found that the ridge vent had been filled with foam insulation. I have read a lot on the topic of spray foam verses blown-in insulation and roof venting requirements. I have not seen in any article of code requirement that addresses the use of both. To vent the right-hand side of the structure, removal of the foam from the ridge cap would be required. As the left-hand side of the home has a vaulted ceiling, would temperature changes in those rooms allow for condensation to form on the sheet rock? This is different than a typical open attic that has spray foam throughout. I get that in this application you don’t necessarily need venting, but the mix of both and the vaulted ceiling is throwing me off. If the entire attic is spray foamed, conditioning the attic apace will be required. Is it best to recommend that the right-hand side also have spray in foam applied, eliminating the need for venting? Thoughts? Thanks.
Hi Richard, welcome back to the forum.
If I am understanding the situation correctly, I don’t see a problem if it is closed cell foam in the vaulted ceiling up to the roof sheathing with no ventilation on the left 1/2 the peak area. And traditional blown in insulation, on the right 1/2 side of the ridge, with adequate ventilation from eave to ridge.
I did that on my last house specifically when I remodeled…1/2 of peak closed cell foam between rafters to roof deck and blown cellulose on the ceiling to the other 1/2 of the peak.
I’m in a cold climate in northern Michigan.
No problem!
How does the soffit channel or soffit bay vent if the ridge vent is sealed with foam? Could it be the ridge is now a vapor diffusion vent?
It doesn’t sound like a problem
I would want to see some pictures in order to comment.
The entire ridge vent, or just the spray foam side? Photos might be helpful. Current standards in some areas require diffusion vents to be installed at unvented attic areas.
Do you have pictures? Are the ridge vents blocked with spray foam preventing the exhaust air from the right side with the blown in insulation? As long as the ridge vent is open so the right side can have proper ventilation from soffit to ridge. I would be good with it.