Energy Star Qualified : ICC-ES Recognized : R-Value = 15.67 unaffected by humidity : Prevents condensation : Prevents 97% of radiant heat transfer : Vapor barrier : Elastic : 19dba contact noise reduction : UV resistant Seals around nails (no leak) : Reflective aluminum foil on each side of 1/8inch thick closed-cell polyethylene foam center : Keeps its shape over time (doesnt collapse) : Rippled surface increases airflow