Hi, I have some storage trusses in my garage the room is 16ft wide by 33ft long. I messed up by listening to a spray foam contractor who convinced me to not put in baffles on the sloped part of the ceiling that meets the attic ( which is about 75") i included a sketchup diagram of what i have going on, is this going to work for condensation? Im in zone 7 i dont care about meeting minimum insulation values for building code. its about 2.75" of CCSF into the 2x8 cavity with an r22 bat of roxul. I have synthetic underlayment on the roof so im worried about no drying potential. I will be covering the knee walls with 6mil poly and then tying in the slope and ceiling with Membrain by certainteed

See the section containing "flash and bat" here and also here (might work anyway). But my opinion is that this "cold sheathing and vapor barrier on the exterior" design isn't very good for your climate. Might also cause some ice dam problems lower on the roof.

If you use a riskier design, I'd pay attention to humidity and pressure (positive is bad in the Winter).

in the picture where the ceiling is sloped is the only place that has spray foam to the deck the roof continues on normally vented on both sides and the roof is vented above. I should have used air baffles to continue into the attic section but i listened to a spray foam contractor against my better judgement. edge of the roof is so far away from the bonus room i don't think any ice dams will occur its another 15 feet away from the knee wall

i wonder if i should pull all the roxul and just spray the 2x8 full

i wonder if i should pull all the roxul and just spray the 2x8 full

That seems like a reasonable fix.

is there any reason a flash and batt with 2.75" of foam will not work in climate 7 though, the building inspector didn't have issue with it but i want to verify with more knowledgeable people on this forum