Insulating a sloped ceiling
I’m remodeling my house in Virgina Beach, Virginia, climate Zone 4. On the lower floor I have a sloped ceiling that follows the same slope as the roof with a 5/12 pitch. When I removed the exiting sheetrock the rafter cavities were filled with R30 high density insulation. I have soffit but there are no baffles and there is not exit ventilation such as a ridge vent because the roof of the lower floor meets the vertical wall of the second floor. I’ve seen a product by Lamanco (Omni Vent) or another product called “Smart Vent” that seems to be designed to vent this type of roof to wall design but I don’t want to install these because I can’t find a roofer in my area that have ever installed them and I don’t want to add more areas for possible water leaks. By code I’m supposed to use R38 but the city inspector told me since I’m approximately 400 sqft and only have 9″ rafter cavities I could install R30 High Density and it would pass inspection. I want to do this as right as possible but not spend a fortune doing it and I’m not a fan of foam as there seems to be conflicting pro’s and con’s plus the expense. Questions: 1) Is it OK the simply put R30HD back as a “like for like” remodel? 2) Should I seal up / close up the soffit opening?
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