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swellstop coil waterstop exampleSwellable Waterstop

Swellstop requires no special skills and installs quickly. As a strip applied waterstop, Swellstop reduces labour costs by eliminating the need for splitforming and fabricated splices.

Swellstop and Swellstop II are a flexible, coiled strip of butyl rubber and a swellable clay waterproofing compound that swells upon contact with water to form a long lasting compression seal in concrete joints.

Product Description


Swellstop is a multiple use waterstop, which is formulated to encapsulate hydrophilic materials into a rubber base creating a controlled, moisture-activated sealant. Swellstop has the structural integrity of a rubber-based sealant, conforming well to the underlying substrate and exhibiting self-healing properties when needed. Unlike many of the traditional cly-based products, Swellstop will not expand to a point that the
waterstop itself is destroyed. In-field experience has proven that products that continually expand lose much of their structural integrity and begin to wash away when subjected to a constant flow of water.

The controlled expansion properties engineered into Swellstop reduce the internal pressures created in cast-in-place applications. Internal pressures can cause spalling in foundations and wall structures.

Swellstop I and Swellstop II also provide excellent secondary protection when used in conjunction with traditional waterstops.

diagram of swellable waterstop applicatio

Swellstop Primer Adhesive is required to assure proper installation. Additional mechanical fasteners may be required for vertical or overhead applications.

Typical Applications

  • Manholes
  • Slabs
  • Box Culverts
  • Parking garages
  • Concrete pipes
  • Retaining Walls
  • Storage tanks
  • Tunnels


A minimum of (2) inches of concrete clear cover must separate Swellstop from the face of the concrete.

Note: In cases of lightweight concrete or insufficient concrete coverage, increase clear cover. 

Swellstop should not be stored exposed to moisture. Should the material become wet during the phasing of the job, check for swell. Should considerable swelling occur before covering with concrete, remove and replace material with new. Use concrete nails to secure the waterstop as necessary.


More Information about Swellable Waterstop

pdfProduct Brochure for Swellable Waterstop

Pdf all about Swellable Waterstop. 

pdfProduct Brochure for Swellable Waterstop

Pdf on how to use Swellable Waterstop.