Garage insulation – attic space options?
When I moved in my garage was unfinished and basically unusable in our hot CA valley summers. Right now I’m finishing the garage walls with insulation and am wondering how to insulate the attic space above once I get ceiling sheetrock up.
Right now the garage is firewalled up to the exposed rafters and there are no roof vents. If I put up ceiling drywall as is, the attic would be unvented and get real hot. To help keep it cooler I was thinking about adding a few vents to get some air flow, maybe a gable fan, and throwing some thick bats on the ceiling sheetrock and calling it a day
But since I plan on reroofing within the next year, my buddy said to look at CA title 24, and I see that they prescribe putting insulation directly against the roof decking. Which would be easy for me to do right now while the roof and support members are totally exposed. But at the same time I am reading that insulation against roof decking can cause a lot of issues unless it’s very well ventilated. Right now there’s no soffit, no vents, just exposed rafter rails with blocking between them.
My first question is when I do reroofing for the whole house, do I have to follow title 24 for roof area above my garage, that is firewalled off from the rest of the attic and doesn’t contain HVAC equipment in the attic?
My second question is what do you think I should do regarding the garage attic, to help keep it cool in hot CA summers?
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