> Extruded Polystyrene foam for insulation use is not sold by density but by > compression resistance. (Beaded white, or expanded Styrofoam is sold by > density). Compression resistance is the property important to us builders > as well. It rates the crush resistance of the core, and so it's ability > to resist buckling. Owens Corning pink foam has a number on it ,(150, > 250, 400, 600), that correlates to it's compression strength. 150 is > 15psi, 250 is 25 psi etc. Dow blue foam is generally 25psi but is > available as High Load 40 (psi) and High Load 60. I some areas, these > High Load foams are marketed as ROOFMATE. Dow GrayBoard is 15 psi. The > manufacturers guarantee the compression strength of the foam to exceed the > rating, the density may vary. Generally speaking 15psi is around 1.3 > pounds per square foot, 25psi around 1.8, 40psi around 2.3, and 60psi > around 2.6. Your mileage may vary. > > John Kappus > > > > RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
