Drywall as Air Barrier for Attached Garage
brianvarick
| Posted in Green Building Techniques on
I have put a lot of work into detailing my exterior walls to be well insulated and air tight. My problem is that my garage is attached with bedrooms above. I bought well insulated doors and I’ll try to make them reasonably air tight but I’m sure it won’t be great. My question is whether I just try to detail the drywall to be an air barrier or put up tyvek and tape the seams. Is it even worth worrying about if the only real infiltration area is the garage door? I assume the air barrier would go on the inside in zone 4?
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Replies
Drywall is a good air barrier. If you need a VAPOR barrier too then you might need to add something else.
Remember to use 5/8” drywall here since code requires that for attached garages to get the needed fire resistance between the garage and the living spaces.
Bill
The barrier between a garage and living space should always be airtight to keep fumes out. A carbon monoxide detector in the bedrooms is a good idea too.
I would detail the drywall. You'll get little rips in the Tyvek eventually. Also, if there were a fire in the garage, the tyvek would be gone in minutes, leaving the unsealed drywall which wouldn't work as well for fire or smoke protection. That's why a basic taping job on drywall is called fire taping, and is required by code anyway.