FOAMULAR® 604 & 604 RB extruded polystyrene insulations are specially designed for use in Protected Roof Membrane Assemblies (PRMA), where the insulation is placed directly over the membrane. The compressive strength of FOAMULAR® extruded polystyrene insulation provides the integrity needed for long-term roof performance. Extruded polystyrene is the type of insulation recommended for PRMA applications. Owens Corning offers four specific types of FOAMULAR® extruded polystyrene insulation for this use: FOAMULAR® 404 and 604; and FOAMULAR® 404 RB and 604 RB. Both the 404 RB and 604 RB extruded polystyrene insulations feature drainage channels running the length of the panel. These are excellent extruded polystyrene products.
Owens Cornings FOAMULAR® extruded polystyrene insulation is an ENERGY STAR® qualified product.