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Can I use 3/4″ foil-faced and backed rigid insulation as an insulation baffle?

schil003 | Posted in General Questions on

…for venting a roof with a soffit-to-ridge venting system?

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  1. GBA Editor
    Martin Holladay | | #1

    Yes. You'll need to install spacers at the sides of each rafter bay, tight to the roof sheathing, to keep an open air space above the rigid foam. Some builders rip boards in their table saw for these spacers, while others use strips made from rigid foam scraps. The air space should be 3/4 in. or 1 in. deep.

    After the spacers are installed, install the rigid foam. Don't forget to seal the edges of the rigid foam with caulk or spray foam to maintain an air barrier.

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