About the SIGnature Torch on System range


The SIGnature Torch on System range is a roofing system intended for both new build and refurbishment projects. SIGnature Torch on System offers a 20 or 25 year warranty (T&C’s apply) dependent on the underlay option selected to tailor the system to your client’s requirements.
The SIGnature Torch on System range includes: a Torch On Cap Sheet, Underlays and Air & Vapour Control Layers (AVCL) and are:
- Suitable for new build and refurbishments as well as warm or cold roofs
- Warranty for 20 or 25 years (when used with a suitable SIGnature Underlay T&C’s apply)
- Available in Black mineral finish
- BROOF(t4) build ups available. Please contact AccuRoof for more details 01509 501731 [email protected]
SIGnature SBS Torch On Cap Sheet
The SIGnature SBS Torch On Cap Sheet is a polyester based SBS modified bitumen torch-on cap sheet which incorporates a fire retardant coating.
Underlay Options
There are three different underlays that can be utilised within the system and it is this that will dictate the warranty period.
SIGnature Underlay25 (Torch On)
- A fully bonded torch-applied, polyester reinforced, SBS modified bitumen underlay. It has an upper surface finish of sand and a thermo-fusible film on the underside. Using this underlay option, if used in conjunction with the SIGnature SBS Torch On Cap Sheet, the SIGnature Torch On system will qualify for a 25 year warranty.
SIGnature Underlay20 (Film-Film)
- A fully bonded torch-applied, glass fibre reinforced, SBS modified bitumen underlay. It is finished on both sides with a thermo-fusible film. Using this underlay option, if used in conjunction with the SIGnature SBS Torch On Cap Sheet, the SIGnature Torch On system will qualify for a 20 year warranty.
SIGnature UnderlaySA (Self Adhesive)
- A self-adhesive, polyester reinforced bitumen membrane used as an underlay within a SIGnature built up roofing system. The membrane is coated on both sides with self-adhesive bitumen SBS elastomeric coating and has a fine mineral upper surface with a 75mm release film selvedge to facilitate rapid installation of lap joints. Using this underlay option, if used in conjunction with the SIGnature SBS Torch On Cap Sheet, the SIGnature Torch On system will qualify for a 20 or 25 year warranty.
Please note these underlays can be directly applied to a torch receivable Insulation Board only, without the requirement of a venting base layer.
A complete Flat Roofing build-up
To complete a full roof build up, we recommend the below products to be used with the SIGnature Torch on System. However, please note additional products used to provide a complete system are dependent on specification and roof type:
SIGnature Air & Vapour Control Layer (Torch Applied)
- A fully bonded torch-applied, polyester reinforced, SBS modified bitumen Air & Vapour Control Layer with an aluminium core. It has an upper surface finish of fine sand and a thermo-fusible film on the underside, To be used over a primed substrate beneath the Insulation to prevent moisture contamination.

- To be used over a primed substrate beneath the insulation to prevent moisture contamination.

- A fast-drying bitumen priming solution designed to seal and prepare dry or slightly damp surfaces prior to applying roofing felt and flashing tapes. To be used to prime all timber and old bitumen surfaces prior to torch application.

- Fast drying primer for adhesion of self adhesive bitumen roofing membranes.
- Spray applied version available. Please contact AccuRoof for more details 01509 501731 [email protected]

The SIGnature Torch on System is available at all SIG Roofing branches throughout the UK. Speak to a member of our staff for help and advice, please click here to find details of your local branch.