Insulation for Partially Bonded, Torched-on, Built-up Bituminous Felt Systems. Torchon/Tissue Flat Roofboard. FR/BGM is faced with a polypropylene fleece finished bitumen/glass fibre working surface and a mineral glass facing to the under side. FR/BGM is part of Xtratherm’s comprehensive range of high performance flat roof boards providing total solutions for flat roof projects. *High Thermal Performance *Compatible with most bituminous based roofing systems *Fleece finished bitumen/glass fibre facings Xtratherm Flat Roof Board FR BGM Data Sheet