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Best method for insulating attic roof rafters?

user-1129453 | Posted in General Questions on

I am finishing my attic for living space. The walls are 5ft up then 3ft diagonal then 8ft flat. (see photo). The kneewall and ceiling are getting r30. What is the best way to get a high r-vaule in the 3ft diagonal that contacts the roof with such a small depth? Ventilation is not going through it.

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  1. GBA Editor
    Martin Holladay | | #1

    To learn about all of the different ways to create an unvented insulated sloped roof assembly, see this article: How to Build an Insulated Cathedral Ceiling.

    Behind your kneewalls, it's best to install insulation at the roof plane (all the way down to your soffits) rather than trying to insulate the kneewalls. To learn why, read this article: Two ways to insulate attic kneewalls.

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