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Basement Rim Joist

Icy2016 | Posted in General Questions on

HI, if I insulate the Rim Joist in my basement, which has a unfinished ceiling, what would be the best way to cover the insulation ?

I’m thinking about mineral wool or foam board for insulation.


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  1. Andrew_C | | #1

    I suggest first looking at Martin's article "Insulating Rim Joists". Use the search function, or follow the link from the "How to Do Everything" article. (Everyone has that one bookmarked, right?)

    Mineral wool insulation is great for many jobs, but you don't want an open insulation against the rim joist, as you're now insulating the rim joist (making it colder) and allowing water vapor to get thru the insulation, risking condensation with all the attendant risks.

    And, which climate zone are you in?

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