SecurShield HD Plus Polyiso Insulation is a high-density polyiso insulation panel specifically designed for use as a cover board in fully adhered systems. This product is manufactured on-line using premium-performance coated glass facers, suitable for both re-roofing and new construction applications. It delivers an R-value of 2.5, which is significantly higher than roof cover boards made with other materials such as wood fiber or gypsum.