Waterproof Tape

Waterproofing membrane tapes are purpose-made adhesive tapes used to seal the laps, joints, junctions and details in structural waterproofing systems. Each product in the range is formulated or specified for use within a particular membrane system, covering damp proof membranes, gas and radon resistant membranes, and pre-applied and post-applied waterproofing for below-ground and ground-level construction. The tapes ensure continuity of the membrane at the points where water ingress is most likely: at laps where sheets overlap, at joints between membrane sections, and at details around penetrations, corners and terminations. They are not interchangeable across systems or brands.

Lap Tapes for DPM and Gas Membrane Systems

In polythene DPM and gas membrane installations, laps between sheets must be properly sealed to maintain the integrity of the membrane. An unsealed or poorly sealed lap is a direct route for moisture, ground gas or radon to bypass the membrane entirely. Lap tapes are applied over the overlap between adjacent sheets to bond and seal the joint, completing the membrane at that point. The Visqueen range covers lap tapes for standard polythene DPM, NF-series membranes and gas resistant membranes including radon barrier applications, in a range of widths to suit different lap and joint requirements. The gas resistant foil lap tape is specifically designed for use with gas membrane systems where standard polythene lap tapes are not appropriate.

Waterproof Jointing Tape for Structural Waterproofing Systems

For pre-applied and post-applied structural waterproofing membrane systems, system-specific jointing tapes are required at sheet joints, overlaps and details. These are engineered products formulated to bond with the membrane's own adhesive layer or surface, maintaining the waterproofing line at every joint and junction.
Sika's SikaProof tape range covers jointing, sandwich and extension tapes for the SikaProof pre-applied waterproofing system, providing a fully bonded joint between adjacent membrane panels and at structural details. GCP Preprufe Tape LT is the specified jointing tape for the GCP Preprufe pre-applied system, sealing laps and construction details before concrete is placed. GCP Bitustik BT is a double-sided self-adhesive butyl rubber tape used as a detailing aid across GCP waterproofing systems including Bituthene and Preprufe, and as a bedding strip for waterstops.

Butyl Waterproofing Tape

Butyl waterproofing tape is a highly conformable, pressure-sensitive tape made from butyl rubber, offering strong adhesion to a wide range of substrates and reliable resistance to water, moisture and ground gases. It is widely used in DPM and gas membrane installations to seal laps, joints and penetrations where a durable, compliant seal is required. The Visqueen 100mm Double Sided Butyl Tape is double-sided, bonding to both the membrane surface and the overlapping sheet or substrate to create a continuous, fully bonded lap seal. Its conformability makes it suitable at irregular surfaces and details as well as standard flat lap joints.

Applying Waterproof Tape in a Membrane System

The substrate or membrane surface must be clean, dry and free of dust, dirt and contamination before any tape is applied. Proper surface preparation is the single most important factor in achieving a reliable bond. Loose particles, moisture on the membrane surface, or contamination from soil or concrete laitance will all compromise adhesion. Tape should be applied with firm, consistent pressure across the full width to ensure complete contact between the adhesive and the surface. In cold conditions adhesion can be reduced, and additional care should be taken to ensure the tape bonds fully before it is exposed to site conditions. Each product should be applied in accordance with the manufacturer's method statement for the relevant system. System-specific tapes should only be used with the membrane system they are designed for. Using a standard polythene DPM lap tape on a pre-applied structural waterproofing membrane will not achieve the bond strength or chemical compatibility required for the system to perform.

Choosing the Right Waterproof Tape

In structural waterproofing, the correct tape is determined by the membrane system being used and the application it is needed for, not by general tape strength or adhesion ratings. The question is not which tape is the most waterproof in isolation, but which tape maintains the waterproofing line of the specified system at laps, joints and details. For DPM and gas membrane laps, select a tape specified for use with that membrane by the manufacturer. For pre-applied waterproofing systems, use only the system-specific jointing tape from the same manufacturer. Where butyl tape is appropriate for the application, ensure the width and format suit the lap dimension being sealed. Using the wrong tape, or skipping the tape stage at laps and joints, creates a discontinuity in the membrane that no amount of correctly installed field sheet will compensate for.

Why Choose Construction Supplies UK for Waterproof Tape?

Waterproofing membrane tapes for structural applications: From lap tapes for polythene DPM and gas membrane systems to system-specific jointing tapes for pre-applied and post-applied structural waterproofing, we stock tapes for below-ground and ground-level membrane applications.

Trusted industry brands: Shop waterproof tape from Visqueen, Sika, RIW and GCP, covering the full range of structural waterproofing membrane systems.

Competitive trade prices: Waterproofing tapes supplied at competitive trade prices with no minimum order value.

Fast UK-wide delivery: Reliable nationwide delivery with free shipping available on orders over £300.

Expert support when you need it: Our team can help you identify the right tape for your membrane system and application. Get in touch @ sales@constructionsuppliesuk.co.uk or call us on 03300 55 32 02.