From IKO
IKO Perforated Slate Underlay is a perforated venting underlay which is sand finished on the top surface and slate finished on the underside. This product is loose laid, and designed to provide a controlled partial bond to a substrate when the subsequent layer is fully bonded in hot bitumen in a built-up roofing system.Features and Benefits Formerly BS 747: 2000 Type 3G Roll Coverage: 10m2 British Standard glass-fibre based Economic roofing materials Category: Roofing Sector of Application: Flat Product Type: Bituminous Membrane Type: Underlay Colour: Slate Product Finish: Mineral Installation Method: Loose Laid Project Type: Commercial Large, Commercial Medium, Commercial Small