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Vapor Barriers and Spray Foam Insulation

Foam it Green closed cell foam is a Class III Vapor Retarder at 3 inches and has an R-value of 21.
International Building Code R702.7.1 Class III vapor retarders are permitted for climate zones 4-8 when R-value of continuous insulation is >5 in 2×4 wall or >7.5 in 2×6 wall.

If your local building code requires a Class II Vapor Retarder, use kraft paper on the inside of the foam.
If your local building code requires a Class I Vapor Retarder, use Visqueen (poly plastic sheeting) on the inside of the foam.

If you’re doing a hybrid wall using Foam It Green in conjunction with fiberglass batt, first, spray in the 2 inches of closed cell Foam it Green. Then, install the batt with the paper facing the inside. (For more information, refer to our 2×4 or 2×6 wall videos.)

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Spray foam kits are quicker and easier to use plus you get a seamless air barrier and high r-value in just 1 inch. Choose Foam It Green spray foam insulation kits and don’t settle for less than you deserve.

If you’d like to start saving money and time today, buy Foam it Green Spray Foam Insulation>> now or call us at 800-516-0949. In 60 seconds you’ll be on your way to paying lots less when you use Foam it Green.