GURU W-S Board is a waterproof tile backer board designed to serve as a structural and waterproof substrate for tiled wall and partition assemblies. The board is constructed with an extruded polystyrene (XPS) foam core that is factory bonded on both sides to a WATER-STOP membrane that extends beyond the core to form an integrated waterproof flange.
The panel is developed in accordance with IAPMO PS106 and certified to ANSI A118.10 and ANSI A118.12 for waterproofing and crack isolation. It is used in shower walls, wet area walls, tub surrounds, and other tile board applications where a continuous waterproof layer is required behind tile finishes.
GURU W-S Board installs directly to wood framing, metal studs, or existing partitions. A tongue and groove edge profile allows vertical and horizontal board connections without banding in standard wet area installations. Steam shower applications require banding at seams. Joints are sealed using a 1/2 inch bead of W-S Sealant on each side of the seam to maintain waterproof continuity.
The lightweight foam board structure simplifies handling and cutting while maintaining dimensional stability. The tile board can also be installed over existing ceramic tile during renovation projects to create a smooth, uniform base for new tile.
Key Features
- Waterproof Foam Board: XPS core with factory-bonded WATER-STOP membrane on both sides.
- Integrated Waterproof Flange: Membrane extends beyond core to assist seam waterproofing.
- Tile-Ready Surface: Accepts thin-set mortar and direct tile installation.
- No Banding Required: Tongue and groove edges eliminate banding in standard wet areas.
- Versatile Substrate Compatibility: Installs over wood studs, metal studs, drywall, and existing tile.
- Lightweight Construction: Easy to cut, transport, and handle.
- Standards Compliant: ANSI A118.10, ANSI A118.12, IAPMO PS106.
Specifications
| Specification | Details |
|---|---|
| Core Material | XPS Foam |
| Surface | Factory-bonded WATER-STOP membrane (both sides) |
| Standards | ANSI A118.10, ANSI A118.12, IAPMO PS106 |
Available Sizes
| Size | Thickness |
|---|---|
| 36 in × 60 in | 1/2 in |
| 48 in × 96 in | 1/2 in |
| 24 in × 96 in | 2 in |
| 24 in × 48 in | 2 in |
This tile board provides a waterproof and tile-ready substrate for shower walls and wet area assemblies requiring a continuous waterproof layer behind tile.
