SOPRA 4897 is an SBS-modified bitumen venting base sheet for use in approved multi-ply membrane and flashing assemblies. SOPRA 4897 is composed of a proprietary formulation of elastomeric styrene-butadiene-styrene (SBS) polymer modified bitumen and is reinforced with a high quality random glass fiber mat. The topside is surfaced with fine mineral aggregate while the underside is surfaced with mineral granules to facilitate venting characteristics.
Prior to installation, unroll SOPRA 4897 onto the roof surface and allow to relax. Position SOPRA 4897 in desired position and fasten to nailable substrate. Subsequent approved inter-ply or cap ply membranes are applied to SOPRA 4897 via cold adhesive, heat welding or hot asphalt. Refer to the SOPREMA SBS Roofing Manual for additional application guidelines.