Rigid Foam on crawl space wall
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I visited a house that had blue rigid insulation on the wall. Am I right in the the blue needs a flame barrier.
What are the options to correct this? Can a foil faced insulation be glued over the top?
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Replies
Robert,
If the crawl space is dry, you can glue drywall to the foam.
This is normally true. A flame spread rating is required for the common blue insulation but can be acheieved if an adequate number of studs are present as in pre-fabricated, pre-formed concrete wall componants with vertical "studs" integrated. If the insulation was installed on a retro-fit assembly, remember that it is less hazardous than the kraft faced fiberglass rim joist insulation that it probably replaced since that is basically a tar soaked paper starter log. For future reference, foil backed is rated for flame spread and is also useful because the backing helps keep the small scraps from crubling so that they can be used later in small applications instead of wasted in the trash.