Recommended Add-Ons
At a Glance
Why Choose This Product
Self-adhesive backing eliminates separate adhesive and field-cut membrane pieces
Seals W-S Board joints, metal washers, and Board-to-Niche connections
Pre-cut 4" × 4" patches simplify repetitive waterproofing details
Creates a tested waterproof layer over approved flat wall areas
Package of 100 supports projects with multiple connection points
Meets ANSI A118.10 and A118.12 requirements and is IAPMO listed
Product Information
The GURU® W-S Patch Peel & Stick provides a fast, clean way to waterproof approved connections and fastener locations in W-S Board wall systems. Made from WATER-STOP membrane with an integrated adhesive backing, each pre-cut patch creates reliable coverage without measuring and cutting separate membrane pieces or applying additional adhesive.
Each 4" × 4" patch is sized for joints between W-S Board panels, metal fastener washers, and connections between W-S Board and W-S Niche components. The consistent square format makes repetitive waterproofing details easy to position and complete, while the 100-patch package keeps larger shower wall projects moving.
The 20 mil waterproofing patch passes ASTM D4068 waterproofness testing, has a 0.3 perm rating, and provides ANSI A118.12 standard-performance crack resistance. It meets ANSI A118.10 and ANSI A118.12 requirements and is IAPMO listed for dependable protection beneath tile in residential and light commercial wall assemblies.
Product Resources
Common Questions
GURU W-S Patch Peel & Stick seals approved flat connections within W-S Board wall systems. It can cover metal fastener washers, joints between W-S Board panels, and connections between W-S Board and W-S Niche components before the tile covering is installed.
The technical data sheet specifically identifies W-S Board-to-Board joints, metal washers, and W-S Board-to-W-S Niche connections. It does not confirm universal compatibility with every tile backer board, so use with another product should be approved by GURU or the complete waterproofing system manufacturer.
Begin with a flat, clean surface that is free of dust and contaminants. Remove the release backing, center the patch over the approved joint or washer location, and press it firmly into place. The patch should make complete contact with the surface without gaps or wrinkles.
No. Each patch has an integrated self-adhesive backing and does not require an additional bonding adhesive. The patch provides WATER-STOP waterproofing at the covered location, but all surrounding seams, corners, transitions, and penetrations must still be treated with the appropriate waterproofing components.
Each waterproofing patch measures 4" × 4" and has an approximate thickness of 20 mil. Every package contains 100 individual patches, providing a consistent pre-cut solution for projects with multiple W-S Board joints, metal fastener washers, or Board-to-Niche connections.
No. The manufacturer specifically states that W-S Patch Peel & Stick should not be used in inside corners, outside corners, or floor-to-wall transitions. These changes of plane require the appropriate waterproofing accessories designed for movement and continuous coverage at those locations.
No. The patches are intended for approved flat, clean surfaces without water pressure. They should only be used for the W-S Board joints, metal washers, and Board-to-Niche connections identified by GURU, following the requirements of the complete waterproofing system.
W-S Patch Peel & Stick meets ANSI A118.10 waterproofing and ANSI A118.12 crack isolation requirements. It is IAPMO listed under product file numbers 9205 and 9990, passes ASTM D4068 waterproofness testing, and is rated for light commercial service under ASTM C627.
