Ardex 8+9 Rapid Waterproofing and Crack Isolation Compound

ARDEX 8+9™ Rapid Waterproofing & Crack Isolation Compound – Gray & White

Protect tile installations with ARDEX 8+9™, a high-performance two-part rapid waterproofing and crack isolation system trusted by tile professionals. This solvent-free, cement-based membrane delivers waterproofing and crack isolation in as little as 90 minutes, making it the ideal solution for time-sensitive projects like showers, kitchens, bathrooms, and wet rooms.

Available in Gray or White to suit a wide range of design and substrate needs.

Features and Benefits

• Fast Track Installation
  Ready for tile in just 90 minutes—accelerates jobsite efficiency and minimizes downtime.

• Quick Flood Testing
  Allows flood test in as little as 4 hours after the second coat—ideal for residential and commercial showers.

• Crack Isolation
  Bridges in-plane substrate cracks up to 1/8" (3 mm) without compromising performance.

• Color Options
  Choose from Gray or White to coordinate with tile layout or visibility preferences.

• Generous Coverage

  • Commercial Unit (2 parts): Up to 300 sq. ft.

  • Kit: Approx. 100 sq. ft. (based on two coats over drywall)

• Versatile Use
  For interior and exterior walls and floors, including bathrooms, showers, steam rooms, kitchens, balconies, and more.

• Compatible with ARDEX Mortars
  Provides strong bonding surface for ARDEX tile and stone mortars.

• Solvent-Free Formula
  Acrylic liquid + cementitious powder—low VOC, easy to apply with roller or brush.

• Efflorescence Barrier
  Reduces migration of salts from substrate to tile surface.

• Shower Pan Liner Alternative
  Meets code requirements and replaces traditional PVC liners in many installations.

Mixing & Coverage Instructions

Mixing Ratios

• Mix 1 (Paintable Consistency)

  • 1 gallon (3.78 L) ARDEX 8 to 9 lb. (4 kg) ARDEX 9

  • Small batches: 1 part ARDEX 8 to 1 part ARDEX 9 by volume

• Mix 2 (Slightly Thicker for Detail Work)

  • 2/3 gallon (2.5 L) ARDEX 8 to 9 lb. (4 kg) ARDEX 9

  • Small batches: 2/3 part ARDEX 8 to 1 part ARDEX 9 by volume

Surface Coverage