Seeking advice for new detached garage insulation and vapor barrier
Nicko23
| Posted in General Questions on
Hello, I am working with a contractor to build new detached garage and am trying to make recommendations on the assembly. It will be oversized two car in climate 6B. It will be unheated but we want it insulated to avoid large temperature fluctuations for items stored inside. Right now I am planning on R21 fiberglass in the walls and R49 loose fill cellulose in the ceiling. Is this the best type of insulation to use in this application? I am also wondering if a vapor barrier is needed in the ceiling and walls if it won’t be heated. If you think it is needed, what type of vapor barrier would be best? Thank you!
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Replies
Nicko23,
You don't need one now, and if down the road you decide to heat the space, you can use a vapour-retarding paint. Do air-seal though. That's something difficult to retrofit.
Thanks Malcolm!
Any reason (besides cost) to not include a vapor barrier on the front end even without heating the garage? If we do include one now would Poly be good for both the ceiling and walls?
What do you think about our proposed insulation?
Nicko23,
No reason not to include a vapour barrier now, and yes poly would be fine.
I have the same feeling about the insulation: Having stuff done now so things are easier in the future if you do decide to heat the space, or even change its use, is a great idea.
I am also wondering about how to mitigate mice and other pests with the insulated enclosed attic above the unheated garage. Seems like it could be an issue. Do folks have any suggestions? Is loose fill cellulose a bad idea in the attic?
Thanks!