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Ardex UI 740 Flexbone Uncoupling Membrane

by Ardex
SKU 24252
Original price $319.00 - Original price $319.00
Original price
$319.00
$319.00 - $319.00
Current price $319.00

ARDEX UI 740 FLEXBONE® Uncoupling Membrane is a high-performance, load-bearing underlayment engineered to prevent cracks, reduce stress transfer, and deliver long-lasting tile installations over challenging substrates. Its bone-shaped cavity design provides superior shear movement control, outstanding mortar grip, and faster overall installation—making it a go-to solution for pros looking for strength, flexibility, and reliability.

More Details

UI 740 FLEXBONE® features ARDEX’s proven uncoupling technology, allowing the substrate and tile assembly to move independently and eliminating the lateral stresses that cause cracking. Its deep-ribbed profile offers optimal mechanical locking of thinset mortars, while the fleece backing ensures strong adhesion to the subfloor. Perfect for large-format porcelain, stone, ceramic tile, and areas subject to thermal movement or moisture exposure.

  • Type: Uncoupling and crack-isolation membrane
  • Thickness: Approx. 1/4" (6 mm)
  • Roll Size: Varies by product selection
  • Backing: Non-woven fleece for strong bond to substrate
  • Benefits: Crack isolation, vapor management, and stress reduction
  • Compatibility: Porcelain, ceramic, stone, and large-format tile
  • Applications: Floors, heated floors, residential and commercial installations
  • Substrates: Concrete, plywood, OSB, and challenging substrates with minor movement
Standards

SystemOne

Shipping & Return Policies

Faster Installs, Stronger Floors, Better Protection

ARDEX UI 740™ FLEXBONE® Uncoupling Membrane is a high load-bearing uncoupling membrane ideal for large format tile in high traffic areas. The unique bone-shaped pattern with GripLock Technology delivers outstanding tensile bond strength. The system helps neutralize underlying substrate movement and supports and distributes heavy loads from above. Special high-performance felt helps provide vapor equalization. ARDEX UI 740 FLEXBONE can be used as a waterproof layer in bathrooms and wet areas.

Key Features

  • PRODUCT ENHANCEMENT: Now with added ventilation channels
  • Prefill with just one pass
  • 3mm thickness (1/8")
  • Easy to handle 39" x 65'5" roll size (215 sq. feet)
  • High load-bearing uncoupling membrane
  • Ideal for large format tile and stone in heavy traffic areas
  • For use with porcelain, ceramic, quarry and natural stone tiles
  • Helps prevent grout joint and tile damage from substrate movement
  • Higher shear and tensile bond strengths than comparable uncoupling membranes 
  • Suitable as a waterproofing membrane
  • For use in high stress areas, such as shopping malls, airports, office buildings, hospitals, etc.
  • For use over wooden or concrete substrates
  • Can be prefilled with ARDEX Liquid BackerBoard® Self-Leveling Underlayment