Greenseal Bentonite Waterstop

A flexible hydrophilic natural rubber & bentonite waterstop for construction joints and sealing precast elements that expands on contact with water. The bentonite in Greenseal Waterstop consists of tightly packed charged microscopic platelets, between and within these platelets there is a separation of charges positive and negative. Water molecules are attracted to the unique structure of positive and negative charges and wedge themselves between the platelets causing them to separate & swell. The hydrated bentonite forms a seal preventing further migration of water. As hydrostatic pressure is increased the platelets compact forming a tighter seal.



  • Lightweight flexible coils easy to install.

  • Eliminates seam welding & split forming associated with PVC/rubber waterbars.

  • Butt end joining, continuous waterstop.

  • Withstands hydrostatic water head up to 70 metres.

  • Forms a positive seal, sealing cracks & small voids.

  • May use in potable water tanks. Non-toxic.

  • Can apply to irregular concrete surfaces. No need to level.

  • Compressible and malleable allowing for good contact in precast applications.

  • Unaffected by repeated wetting & drying cycles.

  • Does not deteriorate lasts life of structure.

  • Fast installation.

  • Permanently active system.

  • Self-healing.


Greenseal Waterstop is used to stop water infiltration through both vertical and horizontal non-moving construction joints, irregular surfaces and around penetrations through concrete. It is not intended as an expansion joint sealant. It is designed to replace conventional waterstops in construction joints. The sodium bentonite in Greenseal Waterstop is the key to its success. Bentonite swells and is released (free expansion) when in contact with water blocking pores, capillaries, minor cracks & other paths for water forming a permanent impermeable barrier.

Typical areas of application include:

Below and above grade structures such as water tanks, waste water treatment plants, tunnels, basements, lift shafts, underground stations, subway systems, manholes, culverts, reservoirs, potable water treatment plants, swimming pools, canals etc.

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