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Rockwool underfloor

raccuia | Posted in Energy Efficiency and Durability on

I am designing a new residential wood structure with TRI-Force Open Web floor joists 16” on center 11-7/8” deep.
I will have 6” Rockwool Thermaboards in between the open web joists with the Rockwool “cut to fit”. There will be a lot of cuts however the cuts are repeated, same cuts for each insulation board.

My question is what would be the best way to make these repetitive cuts. I was thinking a table saw with jigs? I have 280 insulation boards that will need to be cut on both sides.

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  1. Expert Member
    Akos | | #1

    These are best insulated with cellulose. You can loose fill or dense pack. This works for both sound and thermal. Way quicker and cheaper.

    The way I've done it is not to nail down a row of the subfloor, when ready to insulate, cut the tongue and pull up the subfloor for easy access from above. Depending on the span, you might need more than one row.

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