Sikasil® WS-290

Ultra low modulus, neutral cure silicone sealant

Sikasil® WS-290 is a one-part, neutral-curing, ultra low-modulus, low to no bleed silicone sealant that cures to a durable, flexible building sealant Sikasil® WS-290 performs exceptionally well under dynamic conditions due to its ultra-low modulus, high extension/compression, recovery properties and strong adhesion to most building materials. Sikasil® WS-290 accommodates long-term movement of +100/-50 % in properly designed joints and is particularly well suited for use in Exterior Insulation Finish Systems (EIFS). Meets the requirements of ASTM C-920, Type S, Grade NS, Class 100/50, Use NT, M, G, A, O; TT-S-00230C, Type II, Class A; TT-S-001543A, Class A; CAN/CGSB-19.13-M87.

  • Ultra low modulus
  • Unaffected by most atmospheric conditions
  • Excellent resistance to UV and Ozone exposure
  • Non-staining to most porous substrates
  • Joint movement +100/-50 %
  • Excellent adhesion to most substrates and surfaces
  • One-component, moisture-curing
  • Excellent gunnability in all temperatures