Home>Discussions>INSULATION & HVAC>rims joist insulation foam need a fireBlock?
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Timothy Miller
rims joist insulation foam need a fireBlock?

Howdy reading about how one needs to protect foam insulation from the spread of fire... So when i install 2" of foam between the floor joist do i need to then install a fire blocking ? Then i plan on installing fiberglass batts to reduce the heat loss threw the floor into unfinished basement.

ed21
Re: rims joist insulation foam need a fireBlock?

I don't have access to the building code at the moment, but I know thw latest IRBC does not allow exposed foam in an attic, so I assume it wouldn't be allowed in a basement. Coverage can be minimal with metal, plywood or gwb.

canuk
Re: rims joist insulation foam need a fireBlock?
Timothy Miller wrote:

Howdy reading about how one needs to protect foam insulation from the spread of fire... So when i install 2" of foam between the floor joist do i need to then install a fire blocking ? Then i plan on installing fiberglass batts to reduce the heat loss threw the floor into unfinished basement.

Yes , you have to cover the exposed foam with a fire rated material like drywall for example.

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