Should I air seal and insulate above the ceiling of my attached garage?
iLikeDirt
| Posted in Energy Efficiency and Durability on
My house has an attached garage. The attic spaces above the house and the garage are not separated; there is no wall between them in the attic–it’s all just one big attic. I am currently having the part of the attic over the conditioned space air-sealed and insulated. Should I additionally air-seal and insulate the ceiling above the attached garage? Even though it’s not conditioned space? There is a water heater in there FWIW, and the garage does get cold in winter and hot in summer.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Search and download construction details
Replies
Yes, I would air seal it very well! Forget the efficiency or any energy savings. It should be air sealed due to exhaust fumes entering through the garage and into your house area! If it were I in this situation I would positively separate the house attic from the garage attic as a further precaution against noxious fumes. As well as a fire wall to prevent fire spread should there every be a fire in the garage from a vehicle, mower or spontaneous combustion. We are required to do a double layer of 5/8 fire code drywall from garage floor to bottom of roof sheathing no if, ands or buts!
Nathaniel,
You've asked that question before. Here is a link to the page where I answered your question, the last time you asked.