Delayed Swell, Self-Adhesive, Bentonite Waterstop Strip

Description: BentoTak is a delayed-swell bentonite self-adhesive waterstop strip designed to stop water infiltration through cast-in-place concrete construction joints and penetrations. BentoTak bentonite-polymer putty can withstand ponding water for up to 7-days and can be applied in wet conditions. The polymers within Bentotak reduce the swelling capability of the bentonite from 1000% to 200%, increasing the bentonite density within the joint while keeping joint pressure at a minimum. Unlike expanding hydrophilic waterstops that create a rigid gasket water barrier, BentoTak swells within the joint to fill any cracks and voids in the concrete. This swelling action does not subject the concrete joint to excessive expansion pressures which can lead to cracks in and around the concrete joint. BentoTak can be reactivated nearly indefinitely during wet/dry cycling and only activates around the areas of water intrusion.

BentoTak is encased in a poly-vinyl acetate (PVA) film that is a water-activated adhesive, eliminating the need for primers or mechanical fastening.

Composition: BentoTak waterstop strip is a malleable putty made of polymer-modified sodium bentonite clay encased in a PVA water-activated adhesive film.

This product was formally known as Bentotak DS by Kingfield Construction Products.

Please contact EPRO Services for System Details:


  • Active swelling waterstop is fully encased in concrete to seal off water ingress.
  • Ponding water resistant for up to 7 days.
  • Self-adhesive for fast and easy installation.
  • Requires only 1.25-inch (32 mm) concrete coverage.
  • Conforms to rough and irregular concrete surfaces.
  • Seals around pipe penetrations.
  • Effective in both fresh and saltwater.
  • High resistance to hydrostatic pressure.
  • High resistance to groundwater chemical attack and gases.

System Overview:

System Components:


Self-adhesive polymer modified bentonite strip with water-activated PVA film adhesive


System Details:

For System Details, please contact EPRO Services: 800.882.1896 -or-

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