CLWARD’s S-Seal Water-Based Duct Sealant

See the Difference with CLWARD’s S Seal. Where Innovation Meets Performance

Article content provided by CLWARD.

Engineered for high-performance applications, CLWARD’s S Seal water-based duct sealant delivers unmatched durability and is fully certified to meet industry standards. Whether for indoor or outdoor use, this next-generation sealant offers reliability like none other.

What Sets Our Sealants Apart?

  • Exceptional Spreadability
    Designed to reach every crevice, maximizing coverage and minimizing waste.
  • Superior Adhesion
    Delivers a strong, lasting bond to duct surfaces for a tighter, more secure seal.
  • UV Resistance
    Contains polymers to provide excellent UV resistance.
  • Water Resistance
    Built to endure moisture exposure, ensuring long-lasting performance.

Certified Performance You Can Trust
UL Listed, GreenGuard Certified, and compliant with all SMACNA pressure and seal classes, CLWARD’s sealants are redefining what’s possible in duct sealing.

See for yourself.
Check out our short video to learn how S-Seal is transforming the industry: Watch Now

Ready to upgrade?
Discover the difference. Contact CLWARD to upgrade your sealing performance and durability today.

CLWARD – Innovating Assembly, One Corner at a Time.

Please view the entire line of CL WARD products here.

Have a question for CL WARD? Contact CL WARD here.

CL WARD continue to position ourselves as the sought after supplier of sheet metal accessory products to the HVAC construction industry by providing superior customer service and quality products through innovation.


Aug 6, 2025 Products & Services Update

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