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Re R Rating on Loose Cellulose

captainsolar | Posted in Energy Efficiency and Durability on

I know R rating is 3.7 per inch for Cellulose, what is it if roof is filled with 75mm thickness of Cellulose? or what is formula. Would not think it would be 3 times, as never heard of higher rating over 6
Thanks Colin

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  1. GBA Editor
    Martin Holladay | | #1

    75 mm = 3 inches
    R-3.7 per inch x 3 inches = R-11

    R-11 isn't much. Many builders are aiming for R-60 these days.

  2. jklingel | | #2

    Colin: In case you missed it in Martin's response, the R value is PER INCH. 10" = 10(3.7), etc.

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