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CJ FORM-TIE Waterstop Ring

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Product Description

CORKJOINT CJ Form-Tie Waterstops are produced from a unique hydrophilic rubber sealing compound which expands in a controlled fashion when exposed to moisture. This forms a compression seal inside or around the form-tie system in the concrete structure, giving a permanent flexible watertight seal.

Available in a number of different sizes and profiles to suit the form-tie system. Once installed, CJ Form-Tie Waterstops forms a continuous barrier, making it ideal for preventing water penetration or egress.


  • Excellent sealing capabilities and available in many different sizes, shapes and profiles to suit the
    formwork form-tie system to be used. Custom profiles available upon request.
  • Provides a permanent, flexible gasket and compression seal inside the concrete.
  • High quality, non-biodegradable compounded hydrophilic rubber that provides long-term durability
    and integrity.
  • Ability to expand up to 200% in contact with potable water and over 150% expansion in salt water.
    Has been tested to withstand over 50 metres of hydrostatic water head pressure. (Test report available
    upon request)
  • For use in many different types of applications but especially suited for water retaining structures
    where direct water pressure is applied against the concrete and the form-tie system.
  • Non-toxic and can be used in potable water structures.
  • Unaffected by repeated wet and dry cycles.
    Fast and simple to install.
  • Expansion is controlled via the built-in expansion delay system. The product does not pre-expand from
    the water in the freshly laid concrete of the wall, allowing the concrete to gain strength first.

Areas of Application

Water retaining structures:

  • Water Tanks
  • Reservoirs
  • Dams
  • Water Treatment Plants
  • Sewage Treatment Plants
  • Swimming Pools
  • Bund WallsWater excluding structures:

Water excluding structures :

  • Basements
  • Underground car parks
  • Tunnels
  • Stations & Subways
  • Retaining Walls
  • Pits & Manholes

Note : The product’s design and performance, its intended use, installation and final confirmation and approval for use, must be provided by the project’s Design Engineer and Project Manager.


  • Due to the expansive forces of the hydrophilic rubber compound, CJ Form-Tie Rings need to be installed with a minimum concrete cover of 75mm from any outside edge.
  • Increase concrete cover when using lightweight or low strength concrete.
  • Expansion rate can vary in potable water and salt water environments.

Typical Applications

CJ Form-Tie Typical Applications 

Typical Installations



a. Thoroughly clean the outside surface of the form-tie rod, free of any dust, debris & foreign matter.

b. Place the CJ Form-Tie Ring over the outside face of the form-tie rod and slide it along to approximately the middle section.

c. A minimum concrete cover of 75mm from any outside edge of the concrete to the CJ Form-Tie Ring should be followed.

d. Check and make sure that the CJ Form-Tie Ring has a tight and secure fit around the sleeve or rod. If it is loose, then a smaller diameter ring should be used.

e. The CJ Form-Tie Ring is now ready for the concrete to be place.

Test Reports

  • Exposure & Water Immersion Expansion in Potable Water
  • Exposure & Hydrostatic Head Pressure (cyclic wet & dry) in Potable Water
  • Water Immersion Expansion in Salt Water (In-house)

Written Specification

The Form-Tie Waterstop shall be CJ Form-Tie Waterstop (State profile number required) as supplied by CORKJOINT. The Form-Tie Waterstop shall be produced from Chloroprene Rubber and compounded with special hydrophilic polymers to be able to achieve a minimum expansion capability of 200% in potable water and a minimum of 150% expansion in salt water. The Form-Tie Waterstop must be able to withstand a hydrostatic water head pressure of not less than 5 Bar and an independent laboratory test report must be provided to prove the product material type, the water immersion expansion percentage and the hydrostatic water head pressure capabilities.

Health and Safety Information

In confined spaces or in still air conditions, the use of a ventilation fan or suitable respirator should be used, and the advice and approval of the Site Safety Supervisor is essentialFor further information or advice on health and safety precautions, safe handling, storage and correct disposal of products, please refer to the most recent product Safety Data Sheet (SDS)  which is available upon request.


The information and the recommendations relating to the application and end use of this product are given in good faith and are based on the information provided by the manufacturer of the product and/or the Company’s current knowledge and experience in connection with the product when properly stored, handled and applied under normal conditions and no liability of final function at the job site is assumed. In practice, the differences in materials, substrates and actual site conditions are such that no warranty in respect of merchantability of, or fitness for, particular purpose, nor any liability arising out of any legal relationship whatsoever, can be inferred either from this information, or from any written and/or oral recommendations, or from any other advice offered by the Company. The Company also has no express or implied knowledge of any particular purpose for which the product is required and any such information given will not be taken into account in the supply of this product. No responsibility or liability by the Company will be accepted for misuse, misreading or derivation from recommended guidelines in respect of this product and the user shall determine the suitability of the product for his intended use and assume all risks and liability in connection therewith. The information contained in our brochure may change at any time without notice. Any use of this product, CJ Form-Tie Waterstop, in any application should be approved as suitable for use/application by the Design Engineer and Project Manager.