Torch-On Underlay Felt Base Layer for Built-Up Flat Roofing Systems

Torch-On Underlay Felt is a bitumen-based membrane designed to serve as the base or intermediate layer in multi-layer flat roofing systems. Reinforced with a tough polyester or glass fibre core, this underlay provides excellent dimensional stability and strength during installation and throughout its service life.

Supplied in a 1m x 8m roll (8m coverage), the membrane is installed using a propane gas torch, forming a strong bond with the substrate or venting layer. It is typically finished with a cap sheet such as a mineral-faced felt to complete the waterproofing system.

Key Features:

• Roll size: 1m x 8m (8m coverage)
• Ideal as a base or intermediate layer in built-up flat roofing
• Polyester or glass fibre reinforcement for strength and flexibility
• Sanded or film finish for easy torch-on application
• Forms a strong bond when heat-applied
• Compatible with most torch-on mineral cap sheets

Application Areas:

• Garages and outbuildings
• Extensions and porches
• Garden buildings and flat roof structures
• New roofs and refurbishment projects

Note: Torch-on membranes should only be applied by trained professionals using the correct tools and safety procedures.