What it is
PVC waterstops (PVC-Waterstop) are extruded profiles of flexible, plasticised PVC — typically orange or blue — that are cast directly into the concrete at the joints between separate pours: wall-to-slab junctions, kicker joints, pour breaks and movement joints. The profile has ribbed anchoring flanges that lock mechanically into the concrete on both sides of the joint, so water tracking along the joint plane meets a continuous physical barrier embedded in the structure itself. Profiles are made in two families: internally placed waterstops set in the middle of the section, and externally placed (rearguard) waterstops fixed to the formwork on the wet face. Movement-joint profiles include a central hollow bulb that lets the joint open, close and shear without tearing the barrier. Because the waterstop becomes part of the concrete, it protects the joint for the design life of the structure — it cannot debond, age off or be washed out the way surface-applied sealing can.
How we install it
The profile is selected to the engineer’s specification by joint type (construction or movement), placement (internal or external) and expected water pressure. On site the waterstop is set out along the joint line and fixed so it cannot fold or displace during the pour — internal profiles are tied to the reinforcement through eyelets in the outer ribs; external profiles are nailed or clipped to the formwork. Continuity is everything: lengths, corners, tees and crossings are joined by heat welding — the PVC ends are melted against a heated blade and pressed together into a homogeneous joint, with factory-made intersection pieces used at complex nodes. During concreting the mix is placed and vibrated carefully around the profile so both anchoring flanges are fully encased without voids. Where a waterstop cannot be used — retrofits, penetrations, second-stage pours — we complete the joint with hydrophilic seals: swellable profiles and sealants bedded on the prepared joint face that expand on contact with water and compress within the joint to close it. Together these systems form the joint-sealing layer of basements, water tanks and other water-retaining structures, working alongside the membrane systems we install.
Material systems
Systems we install / are manufacturer-trained on — not partnerships.
Used for
- Basements / below-grade structures
- Water tanks
- Construction joints
- Movement / expansion joints