DOWSIL™ 888 Silicone Joint Sealant 20oz Sausage


A single-component, non-sag silicone material that transforms into a low-modulus silicone rubber upon exposure to atmospheric moisture. Suitable for application across a broad temperature range.

Technical Data Sheet


  • Suitable for new construction, repair, or remedial applications.


  • Can be extruded within a wide temperature range from -20 to 120°F.
  • Effective for use in joints with varying widths.
  • Offers a movement capability of 100% extension and 50% compression.
  • Features a low modulus for enhanced flexibility.
  • Resistant to weather and UV radiation.
  • Provides short-term resistance to fuel exposure (refer to Dow form number 62-207 for detailed information).
  • One-component formulation, cold applied, and ready-to-use straight from the container; can be dispensed manually or with an air-powered pump directly into the joint.
  • Exhibits unprimed adhesion, eliminating the need for a primer when bonding to Portland cement concrete. For optimal adhesion, ensure the surface is clean, dry, and free from frost.
  • Typically cures within one hour or less under standard conditions, forming a skin-over.
Typical Properties
Adhesion to Concrete, Masonry
Appearance Opaque
Chemistry Neutral
Color Grey
Durometer - Shore A 15 Shore A
Elongation > 1000 %
Modulus @ 150% Elongation, maximum 28 psi
Movement Medium
Shelf Life 360 Days
Specific Gravity @ 25°C 1.48
Substrate Porous
Application Benefits
Application Temperature Range -29 to 49 °C
Primerless Adhesion Primerless
Resistance Type Fuel Resistance, Jet Fuel Resistance, Ozone Resistance, Thermal Resistance, UV Resistance, Water Resistance
Water Resistant true
Processing-Formulating Benefits
Cure System 1-Part Cure
Full Adhesion Time 14 to 21 Days
Number of Parts One
Room Temperature Cure - Days 7 to 14 Days
Tack-Free Time-50% RH 60 Minutes
Where Used Job Site


Additional information

Weight 2.5 lbs
Dimensions 1 × 1 × 1 in