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Cathedral ceiling insulation method advice

h20vaultceiling | Posted in Energy Efficiency and Durability on

I have a 1970s house with cathedral ceiling in the living room. We tried to get the house insulated up to code and need some advice. One insulation contractor came back with suggesting spraying 2″ closed cell form in the cavity and add 8″ fiberglass batt to make it R39. He called it a hybrid method. Does this work? Will moisture trap between fiberglass batt and the closed cell form creating condensation?

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  1. GBA Editor
    Martin Holladay | | #1

    This method is called "flash and batt." For more information on the flash-and-batt method, see these two articles:

    Why Flash and Batt Makes Sense

    Flash and Batt Insulation

    To read about other ways to insulate a cathedral ceiling, see How to Build an Insulated Cathedral Ceiling.

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