• Credit: Courtesy InsulFoam

InsulFoam’s HD Composite insulation board bonds closed-cell, expanded polystyrene (EPS) foam together with a 1/2" thick, high-density polyisocyanurate cover board. Available in 4'-by-8' sheets, the insulation board comes in thicknesses between 1.5" and 7" and provides R-values from 6.4 to 25. It can be used with single-ply-membrane, built-up, and modified-bitumen roof systems or as an underlayment for metal roofing systems. HD Composite’s 100% recyclable, HCFC- and formaldehyde-free foam has a compressive strength ranging from 10 to 60 psi and weighs 1 to 3 pcf. • insulfoam.com

Note: The image has been updated since first publication to show the correct InsulFoam product.