Butyl Rubber Waterstop for Concrete Constructions

Several strips of butyl rubber waterstops in the carton box.
Butyl rubber waterstop in carton box package.

Butyl rubber waterstop is a type of hydrophilic water sealing product to prevent any passage of water through non-moving construction joints. Composed of quality butyl rubber and mastic or expansible clay, when exposed to water, the waterstop swells and forms a permanent compression seal in non-moving concrete construction joints.


  • Preserve its integrity with self-control ability.
  • Easy and fast to install owing to its high self-adhesive properties to dry surface.
  • Form a permanently flexible watertight joints.
  • Anti-aging without shrinkage, hardening and oxidization.
  • Withstand harsh temperatures ranging from -30°F to 200°F.
  • Non-toxic.
  • No need of special handling.
A piece of black butyl rubber waterstop and one end is expanded by absorbing water
Butyl rubber waterstop with water expansible characteristic


  • Concrete construction joints.
  • Non-moving joints.
  • Portable water tank, box culverts and tunnels.
  • Water containments.
  • Pipe penetrations.
  • Manholes.
  • Slab and walls below grade.
  • Cast in place applications.
  • Foundations and basements.
  • Utility and burial vaults.
  • Precast concrete wall panel system.
  • Wet wells.


Physical properties Test method Type BRWS-1 Type BRWS-2 Type BRWS-3
Color - Black Black Black
Material - Butyl and mastic Butyl and mastic Butyl and expanded clay
Specific gravity ASTM D-71 1.35 1.22 1.60 ± 5%
Volatile matter ASTM D-6 1% 1% 1%
Penetration, cone at 77°F, 150 gm, 5 sec. ASTM D-217 40 mm 62mm 40 ± 5 mm
Application temperature - -10°F to 125°F -30°F to 200°F -10°F to 125°F
Service temperature - -30°F to 180°F -30°F to 200°F -30°F to 180°F


  1. Before installation, do not forget to clean and dry the surface of the concrete.
  2. Butyl waterstops should be stored in cool, dark and dry environment, away from moistures. 
  3. Not appropriate for expansion and moving joints.
  4. Please make sure a minimum 2 inches of concrete coverage is left before installation to reduce spalling and cracking of surrounding concrete caused by expansion pressure of the waterstop. When it comes to lightweight, low strength and insufficient concrete with low compressive strength less than 3500 psi, please increase the coverage.
  5. Before the second pour of concrete, check the waterstop for premature swell, discontinuity and debris contamination. If so, immediately replace it with a new one.
  6. Concrete nails are acceptable to fix the butyl waterstop if necessary.