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Covering Closed-Cell foam required?

I am having my garage ceiling and rim joists sprayed with Closed-Cell insulation. I have a bonus room above where the floors are just to cold. Do I have to put drywall over the insulation after it is sprayed in the garage ceiling, or can it be left exposed? The garage is neither heated or cooled.

Re: Covering Closed-Cell foam required?
jkirk wrote:

yes the foam does have to be covered, for fire reasons. if it catches fire it gives off very gases which are highly toxic therefore most building authorities require it to be covered

Thanks, that's exactly what I thought.

Re: Covering Closed-Cell foam required?

Garages are required to have fire rated sheetrock (5/8 inch) on the walls and ceiling separating it from the house. Otherwise, the foam needs to be covered by 1/2 inch sheetrock. The code allows an exemption from coverage of up to 3 1/4 inch of closed cell foam at the rim joists.

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