How to properly vent a modfied gambrel roof?
My family and I purchased a 2 story modified Gambrel style home 5 years ago. By modified, I mean that the vertical roof sides go all the way to the foundation. So we have sloped interior walls upstairs and downstairs.
I live in Zone 6A. We all know what this winter has been like. Ive got an ice dam at the top of the vertical roof on both sides. There has been a fairly large crack in the downstairs sheetrock since moving in, just haven’t started our interior renovations yet. Last week that crack started falling apart and is wet. Further inspection shows wet sheetrock/carpet upstairs, attic frost/moisture in attic, and a frozen patch on the outside of the vertical roof matching the crack.
I know I need to fix the air leak to the attic (the crack). And I need to reinsulate this area at a minimum due to the moisture.
What Im not sure about is how to permanently fix the ventilation problem. There are no soffit vents at the bottom of the vertical roof or at the transition to the typical sloped roof. There are gable vents in the attic, no ridge vent.
I had a couple contractors out to look at this weekend and they are suggesting a complete sheetrock removal, add soffit vents, install baffling for the entire vertical wall, reinsulate, re-sheetrock. They aren’t sure how to add soffit vents to the vertical roof, as there is no overhang, and they will get plugged with snow on occasion since the vertical roof starts 1.5-2′ above grade.
Ive got other people telling me that what they plan to do will create a bad fire hazard, by venting the entire wall with no fire blocks. I think I agree. Ive also had suggestions on using a spray insulation in the vertical roofs to stop all air flow.
How should this be done properly? We may try to tie in an addition to this “remodel”, so there will be a chance to properly fix that side of the house how we choose. But the side with the current issue is likely to remain the way it is.
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