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Product Information
Technical Datasheet


Hydrophilic expandable rubber section for watertight construction joints; availabe in two sizes, 20x10 mm and 20x15 mm, labelled Idrostop 10 and Idrostop 15. Idrostop is a soft preformed flexible strip, with an acrylic polymer base specially designed to form watertight construction joints up to a hydraulic pressure of 5 atm. Idrostop does not contain bentonite. Due to its chemical composition Idrostop gradually expands when in permanent contact with water, creating an active barrier against pressurized water (positive and negative). Idrostop strip can be applied to concrete, metal, PVC and natural stone with Idrostop Mastic, a ready to use solvent-free single component adhesive with a base of MS polymers.


  • Waterproof joints between concrete beds and elevation walls.
  • Waterproof contact joints between different building materials, e.g. steel and concrete, or stone and concrete.
  • Contact joints between different types of materials, e.g. PVC or steel tubing going through poured concrete in swimming pools, sewage-treatment tanks, reservoirs, and hydraulic projects in general.
  • Waterproof cooling joints (temporary shrinkage joints) created during pouring to reduce the risk of cracking in long or monolithic structures.
  • Waterproof construction joints where conventional water-stop cannot be installed easily and securely because of the high density of the reinforcing.
  • Waterproof construction joints in tunnels, dams and hydraulic projects including reservoirs for drinking water.

For creating water tight construction joints in civil, industrial, and hydraulic construction.