IKO Glass Fibre Underlay 3B

IKO Glass Fibre Underlay 3B

IKO Glass Fibre Underlay is a waterproofing membrane consisting of a strong glass-fibre base coated with APP. It is sand finished on both surfaces.

Used as an economical underlay (or intermediate layer) in a built-up felt roofing system, it is usually fully bonded in hot bitumen. It is also used as an underlay to bitumen shingles in a pitched roof application.

This range of IKO glass-fibre roofing membranes consists of underlays and capsheets, complying with former BS 747: 2000 Type 3 where applicable.

The products usually have an oxidised bitumen coating and are either sand or mineral surfaced. These products are usually applied with hot bonding bitumen or cold bitumen adhesive.

Used beneath shingles in boarded pitched roofs mechanically fixed with large headed galvanised clout nails.

Key benefits to your project

  • Formerly BS 747: 2000 Type 3B.
  • British standard glass-fibre-based.
  • Economic roofing materials.

Product information

Brand: IKO
Product colour: Black
Product finish: Sand
Product type: Bituminous
UK manufacturing: Yes
SKU: 03842000

Key performance criteria

Accreditation: ISO 9001, ISO 14001, ISO 45001
By project type: Commercial Small, Domestic Large, Domestic Medium, Domestic Small
Certification: CE
Installation method: Mechanically Fixed, Pour and Roll
Membrane type: Underlay
Profession: Merchant, Roofer
Sector: Flat
Usage: Flat Roof, Pitched Roof, Pour and Roll System


Length (mm): 20000
Weight (kg): 35
Width (mm): 1000