Biokil Crown 20mm Stud Membrane – Black High-Capacity Cavity Drainage Membrane for Basement Floors and Ground-Bearing Slabs Biokil Crown 20mm Stud Membrane – Black is a heavy-duty, high-capacity cavity drainage membrane designed for use on basement floors, raft foundations, and ground-bearing slabs where maximum drainage and water movement is required. Manufactured from high-density polyethylene (HDPE), the 20mm stud profile creates a large drainage void beneath floor finishes, directing water to internal drainage systems or sumps as part of a Type C waterproofing solution. Key Features & Benefits 20mm Stud Height: Provides superior drainage capacity for high water table or flood-risk environments. Ideal for Type C Systems: Designed for use in cavity drainage systems in accordance with BS 8102:2022. Durable HDPE Construction: Tough, impact-resistant membrane for long-term below-ground installation. Floor Protection: Isolates finishes from damp or contaminated concrete slabs and helps manage hydrostatic pressure. Compatible with Drainage Channels: Easily integrates with perimeter drainage systems and sump/pump units. Product Details Material: High-Density Polyethylene (HDPE) Stud Height: 20mm Thickness: Approx. 1.0–1.2mm Roll Size: Typically 2m x 20m (40m²) Colour: Black Application: Floor slabs, basement floors, ground-bearing concrete SKU: BC20MMBLK Application Instructions Surface Preparation: Remove debris and sharp projections. Ensure slab or substrate is even and structurally sound. Roll Out Membrane: Lay Biokil Crown 20mm Membrane stud-side down, cutting to size as required. Join & Seal: Overlap sheets or butt-joint and seal with appropriate tape or jointing accessories. Connect Drainage: Ensure water flows freely into perimeter drainage or sump systems before applying floor finishes. Limitations Not suitable for use as a standalone waterproofing system – must be installed as part of a managed cavity drain system. Not designed for wall application – use Biokil Crown 3mm or 8mm membranes for walls. Health & Safety Always wear gloves and protective clothing when cutting or handling. Refer to the product's Safety Data Sheet (SDS) for full health and safety guidance.
