FM 4770 is the approval standard through Factory Mutual for single-ply, polymer-modified bitumen sheet, built-up roof and liquid applied roof assemblies for use in Class 1 and noncombustible roof deck construction.
Design, Consulting, & Testing
FM 4770 is the approval standard through Factory Mutual for single-ply, polymer-modified bitumen sheet, built-up roof and liquid applied roof assemblies for use in Class 1 and noncombustible roof deck construction.