Can tube washers be used under Torch-on reinforced bituminous membranes?

Torch-on reinforced bituminous membranes (RBM) are still quite widely used for flat roofing applications. The risks associated with working with an open flame need to be taken seriously and guidance from NFRC Safe2Torch is freely available.

NFRC Safe2Torch guidance

Can plastic tube washers be used?

Torch-on membranes can be used in both cold roof and warm roof construction. In warm roofs where there is insulation beneath a torch-on membrane, this can be mechanically fastened using tube washers. Tube washers can also be used to secure a base layer of the membrane where there is a torch-on membrane above.

Whilst the tubes are not non-combustible, they will not melt or catch fire as long as the gas torch is used correctly. When using the gas torch, it is important to keep it moving rather than applying excessive heat in one place, especially not directly over a tube washer.