RetroPlus Roof Board from Johns Manville, a Berkshire Hathaway company, is made of 40% recycled content for which it has UL Environment environmental claims validation. RetroPlus can be used in both single-ply and bituminous commercial roofing systems, as well as mechanically attached single-ply systems. The roof board is water and fire resistant, has wind uplift values up to I-180, and offers high compression- and tensile-strength compared to wood fiber board. RetroPlus has been approved for use in specific UL Class A constructs and meets or exceeds ASTM C728, Type 2.