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Previous owner’s handiwork in detached garage

ryryry | Posted in Energy Efficiency and Durability on

Hi there,

I recently bought a home in Nova Scotia with a two-car detached garage (built ~2001). The garage is wired, but there is no heating system. I will probably use a space heater on particularly cold days, but have no plans to regularly condition that space. I’ll use it as a workshop for the most part, so no wet cars inside, but I will store some lumber.

The roof is uninstalled with gable end vents and no ridge vent. The previous owned insulated the 2×4 cavities with FG batts and put poly on the interior surface. The poly is only stapled (no acoustical), and one wall has no poly at all, i.e. it’s just exposed batts

there’s one corner where the poly was poorly attached, and it looks like that’s where air infiltration concentrated; the batts and poly are black where the sheet came loose from the wall.

Instead of sealing this area back up and fnishing the last wall with poly, I’m inclined to take the poly off entirely. the space isn’t conditioned, so vapour diffusion shouldn’t be an issue. The walls won’t be as air-tight, but with two garage doors, it feels like a lot of wasted effort to get a good seal with the poly.

in the future I do want to finish the walls, and perhaps even install a wood stove.

What say you? Take the poly down or fix/finish the job that was started?

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  1. GBA Editor
    Martin Holladay | | #1

    Airtightness makes a big difference. I would continue to use the poly -- because it's a lot better than nothing.

    When you are ready to install drywall or taped interior plywood, you'll be adding a more durable air barrier, and the poly would at that point become optional.

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