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Rockwool (Roxul) sheet sizes. [2′ x 4′ or 4′ x 8′]

ethant | Posted in Green Building Techniques on

We’re about to start insulating the foundation walls with Rockwool/Roxul Comfortboard IS 80.

In all of my reading I have seen theses boards come as 2′ x 4′ boards. Even then I have read of some difficulty handling.

Our supplier is suggesting 4′ x 8′ boards of the same product, but I am worried that this will be even more difficult to work with.

Has anyone here worked with Comfortboard for vertical exterior insulation and have experience witht he 2′ x 4′ or 4′ x 8′ board sizes? Any thoughts on the matter?

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  1. user-2310254 | | #1


    I will offer a reply so we can bump this question back to the top.

    If you have adequate access and a helper or two, I could see where 4x8 sheets would be more efficient than 2x4 sheets. Conversely, if space is limited and you are working solo, the smaller sheets seem to make more sense.

    If the bigger sheets are cheaper, I would buy them along with a Bahco or similar insulation knife.

  2. ethant | | #2

    Steve. Thanks for your reply and for the recommendation of the Bahco. I have also seen the Skorbord ( which at $1000 is pretty pricey, but not as pricey as a bunch of ruined Rockwool or a bunch of man-hours spent wrestling with substandard tools.

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