Products / Atlas ACFoam-HD CoverBoard

High-density polyiso roof cover board: a closed-cell polyisocyanurate foam core bonded on both sides to inorganic coated glass facers. Supplied 0.5 inch thick in 4 ft x 8 ft and 4 ft x 4 ft panels with an LTTR value of 2.5; the HD CoverBoard-FR variant is 0.625 inch thick, is also listed for standing seam metal, and Atlas states it can be part of a UL Class A fire-rated deck assembly. Manufactured to ASTM C1289 Type II, Class 4, Grade 1 (80 psi minimum, up to 110 psi) and CAN/ULC 704.1 Type 4, Class 3. Used in mechanically attached, fully adhered and self-adhered single-ply roof systems. The data sheet lists FM 4473 SH-1 (severe hail), UL Class B over combustible decks with UL-classified membranes for the 0.5 inch board, and UL Class A over combustible decks for the FR variant.