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 shape 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.


  • High load-bearing uncoupling membrane
  • Ideal for large 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 movement and deflection
  • Higher shear and tensile bond strengths than comparable uncoupling membranes (independent tests at MPA Wiesbaden, Germany)
  • 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


Size and Coverage Available

3 mm Uncoupling Mat - 39" wide x 65.5' long (1 m wide x 20 m long) roll

Coverage of 215 sq. ft. (20 sq. m) per roll

UI 740 Flexbone

  • 215 sq. ft. per roll

  • 3 mm Uncoupling Mat - 39" wide x 65.5' long a roll

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Corporate Office


13735 Lakefront Drive

Earth City, MO 63045



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