CertaFlash™ Flex Ideal for use around arched windows, window flanges, sill plates, corners and joints. The CertaFlash Flex formulation is based on a two-ply, high density polyethylene film mated to a premium butyl rubber adhesive and erlease sheet which provides a tight bond to wood, vinyl, metal and other common building materials. CertaFlash Flex helps improve air and moisture holdout. It conforms well and the peel-and-stick design makes it easy to apply.

Technical Information


For maximum effectiveness, it's critical to finish your CertaWrap installation with tight sealing methods. CertaWrap accessories offer everything needed to get the job done right. Use them to seal window and door openings, cracks, seams, and penetrations prior to applying exterior cladding. See complete installation manual to the right.

Warranty Details

CertainTeed: Peace of Mind CertaWrap Weather Resistant Barrier carries a Limited Lifetime Warranty on material, offering protection for a lifetime of the homeowner. This warranty is also transferable to the first subsequent property owner. Only CertainTeed offers the extra protection of SureStart ™. With SureStart, CertaWrap Weather Resistant Barrier carries and additional 10-year labor coverage after installation when installed as a system with CertaTape and CertaFlash accessories. Be sure to read the warranty for specific warranty conditions.

Sustainability Information

CertainTeed cares about the environment, and believes in sustainable manufacturing processes. Wherever possible we produce products using recycled content, work to decrease raw materials consumption, and strive to reduce waste. Our products help building professionals meet green building standards, and enable homeowners to achieve greater energy efficiency.

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