Ardex UI 740 Flexbone Uncoupling Membrane​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

1 Review

Contractor pricing
Available in CT Warehouse More Info
Available in UT Warehouse More Info

Product Details

Product Details

Ardex UI 740 Flexbone Uncoupling Membrane​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

Ardex UI 740 Flexbone Uncoupling Membrane is a high load-bearing sheet membrane ideal for laying large format tile in high traffic areas. The unique bone shape pattern with GripLock Technology delivers outstanding tensile bond strength between the membrane and mortar. The Flexbone system helps neutralize substrate movement by distributing heavy loads from above. Flexbone Uncoupling membrane can also be used as a waterproof layer in bathrooms and other wet areas.


  • 3 mm Uncoupling Mat
  • 39" wide x 65.5' long (1 m wide x 20 m long) roll
  • Coverage: 215 ft.² (20 m²) per roll
  • 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 movement and deflection
  • 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
Questions & Answers
1 questions

How many Bags of Thinset does it take to embed and fill in bones? X5 vs. X77?

Assuming your substrate is smooth and flat before laying the membrane you can use the fine saw tooth trowel which is 1/8 x 1/8 x1/8 and that will cover about 150-200 sqft.

For the X5 using a 1/4 x 1/4 x1/4 notched trowel you will be able to cover 28 sqft. With the X77 using the same trowel you will be able to cover 35sqft.

Depending how much square foot coverage you need to fill your room will depend on how many bags you will need

Ratings & Reviews

1 review

  • 4 stars
  • 0 reviews
  • 3 stars
  • 0 reviews
  • 2 stars
  • 0 reviews
  • 1 star
  • 0 reviews
2/8/2022 8:17 pm

Great uncoupling membrane!

by Seth -

Great product. One was on back order when I ordered, but Coontractors Direct shipped it out promptly when it came in.