Ultraseal Flex 25

One Component Silane-Modified Polymer-Based Sealant

Ultraseal Flex 25 is a high-performance, one-component, silane-modified polymer-based sealant that acts as a bond breaker for Kerakoll and Keratrade membranes. Moisture-cured, it forms a soft, elastic seal with strong adhesion for indoor and outdoor use.

Key Features

• 600% elongation, accommodates significant joint movement without cracking
• ±25% movement capability, ideal for expansion joints and dynamic surfaces
• Low modulus and low shrinkage, maintains flexibility with minimal stress on substrates
• No isocyanates or solvents, safer for users and better for indoor air quality
• Excellent adhesion to most construction materials
• Suitable for interior and exterior use
• UV, weather, and water resistant
• Non-bubbling, moisture-cure technology
• Easy to apply, smooth finish, paintable and compatible with most coatings

VOC Ratings / Eco Notes

• Solvent-free, low odour
• Green adhesive system

Certifications / Ratings

• BuildGreen Guarantee

Available in 600ml sausages

Skin Time: 10 – 40 min

Cure: 4 mm/day

Temp Range: +5°C to +40°C

Shore A: 30

Stress @100%: 0.6 MPa