USG™ Durock® Liquid Waterproofing & Crack Isolation Membrane is a liquid-applied, acrylic polymer–based elastomeric membrane designed for waterproofing, crack isolation, and vapor control in tile and stone installations. It is approved for use over a range of substrates in wet areas for both residential and commercial applications.
The membrane provides anti-fracture protection over shrinkage and other non-structural cracks while maintaining a low permeance rating suitable for steam showers and continuous-use wet environments. The material changes color when cured to help confirm readiness for tile installation.
Key Features
- Waterproofing and Crack Isolation: Provides waterproofing and anti-fracture protection over non-structural cracks up to 1/8" (3 mm).
- Low Permeance Rating: Rated at 0.38 perms at 20 mils dry thickness when tested to ASTM E96 Procedure E.
- Steam Shower Approved: Meets permeance requirements for steam rooms and steam showers without an additional vapor retarder.
- Multiple Application Methods: Can be applied by roller, brush, trowel, or sprayer.
- Substrate Compatibility: Bonds directly to concrete, masonry, cement backerboard, gypsum-fiber panels, gypsum-based cement toppings, stainless steel, PVC, and ABS drains.
- Color-Change Cure Indicator: Changes color during curing to indicate readiness for subsequent installation steps.
- Flexible Coat Requirements: One coat on smooth vertical substrates; two coats on rough substrates and all horizontal applications.
Approved Applications
- Shower walls and floors
- Steam showers and steam rooms
- Wet area walls and countertops
- Floors requiring crack isolation
- Shower pan liner installations (per IPC 417.5.2.5 and UPC 408.7)
Coverage Rates
- Waterproofing (Smooth Substrates): 80–100 ft² per gallon with one coat, or 40–50 ft² per gallon with two coats at 15–20 mils wet film thickness per coat.
- Crack Isolation (Smooth Substrates): 25–30 ft² per gallon with two coats at 25–30 mils wet film thickness per coat.
- Note: Coverage may be reduced on porous or rough substrates.
Specifications
| Specification | Details |
|---|---|
| Product Type | Liquid-applied waterproofing and crack isolation membrane |
| Compliance | ANSI A118.10, ANSI A118.12 |
| Permeance | 0.38 perms at 20 mils dry thickness |
| Crack Isolation Capacity | Up to 1/8" (3 mm) non-structural cracks |
| Available Sizes | 1 gallon (3.78 L), 3.5 gallons (13.2 L) |
USG™ Durock® Liquid Waterproofing & Crack Isolation Membrane provides a single-system solution for waterproofing, vapor control, and crack isolation in tile and stone installations across wet and steam environments.
