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Can an Attic be Made Conditioned Without Using Foam Adhering to Roof Deck?

carpeverde | Posted in Green Building Techniques on

To avoid the complications of toxicity related to spray foam insulation, is there any way to provide a conditioned attic using an insulation other than foam adhered to the underside of the roof deck? Can rock wool batts or other material for example be used as a substitute?

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  1. acrobaticnurse_Eli | | #1

    What climate zone do you live in? For climate zone 1, 2, or 3 a vapor diffusion port could enable use of fluffy insulation vs spray foam or rigid insulation.

    1. carpeverde | | #3

      Thanks for your help. I live in climate zone 2A

  2. MartinHolladay | | #2

    Cape Verde,
    In climates colder than Zones 1, 2, or 3, there are two other options:
    1. Include an adequately thick layer of rigid foam on the exterior side of the roof deck.
    2. Create a vented roof assembly, with a continuous ventilation channel between the top of your insulation layer and the underside of your roof sheathing, from your soffit vents to your ridge vent.

    More information here:
    "How to Build an Insulated Cathedral Ceiling."

    1. carpeverde | | #4

      Thank you, Martin for your suggestions. Yes, I'm in 2A climate zone and was thinking already about having the continuous ventilation channel. That way, the attic in the summer at least would have a lower delta T with the ambient temperature above the roof. A white metal roof will help too.

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