---
product_id: 220859386
title: "ARDEX FLEXBONE UI 740 Uncoupling Waterproofing Polyethylene Membrane 215 Sq Ft Roll, 1/8\" Thick, Load Bearing Underlayment for Large Format Tiles in Heavy Stress Areas -1 Roll"
brand: "ardex"
price: "107011 kr"
currency: ISK
in_stock: true
reviews_count: 1
category: "Ardex"
url: https://www.desertcart.is/products/220859386-ardex-flexbone-ui-740-uncoupling-waterproofing-polyethylene-membrane-215-sq
store_origin: IS
region: Iceland
---

# 215 sq ft coverage 1/8" thick durable membrane Unique bone-shaped stud pattern ARDEX FLEXBONE UI 740 Uncoupling Waterproofing Polyethylene Membrane 215 Sq Ft Roll, 1/8" Thick, Load Bearing Underlayment for Large Format Tiles in Heavy Stress Areas -1 Roll

**Brand:** ardex
**Price:** 107011 kr
**Availability:** ✅ In Stock

## Summary

> 🛠️ Elevate your flooring game with ARDEX FLEXBONE – where durability meets precision innovation!

## Quick Answers

- **What is this?** ARDEX FLEXBONE UI 740 Uncoupling Waterproofing Polyethylene Membrane 215 Sq Ft Roll, 1/8" Thick, Load Bearing Underlayment for Large Format Tiles in Heavy Stress Areas -1 Roll by ardex
- **How much does it cost?** 107011 kr with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.is](https://www.desertcart.is/products/220859386-ardex-flexbone-ui-740-uncoupling-waterproofing-polyethylene-membrane-215-sq)

## Best For

- ardex enthusiasts

## Why This Product

- Trusted ardex brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Maximize Floor Protection:** Covers a generous 215 sq ft per roll, perfect for large projects without constant reordering.
- • **Vapor Equalization Mastery:** Ventilation channels and high-performance felt prevent moisture buildup, protecting floors from hidden damage.
- • **Engineered for Heavy Traffic:** Extra heavy load-bearing rating ensures tile integrity in busy commercial and residential spaces.
- • **Waterproof & Crack-Isolating:** Effectively uncouples tile from subfloor movement, preventing cracks and grout failure for long-lasting floors.
- • **Innovative Grip Lock Technology:** Bone-shaped studs lock thinset mortar in place with one pass, speeding installation and boosting adhesion.

## Overview

The ARDEX FLEXBONE UI 740 is a premium German-engineered uncoupling and waterproofing membrane designed for large format tile installations. Measuring 1/8" thick and covering 215 sq ft per roll, it features a unique bone-shaped stud pattern with grip lock technology for superior mortar adhesion. Its ventilation channels and high-performance felt provide essential vapor equalization, making it ideal for high-traffic commercial and residential areas prone to moisture and subfloor movement. This membrane ensures long-lasting tile protection by preventing cracks, buckling, and grout damage.

## Description

The ARDEX UI 740 is a durable uncoupling crack isolation membrane for safe tile flooring installation. It lays over the subfloor below, which protects the tiles and surfaces above from harmful developments such as lateral movement, shifts, and existing cracks. With its load-bearing capabilities, this waterproofing membrane can be used to protect your tile and floors in heavy and high-traffic areas. Its ventilation channels and high-performance felt allow vapor pressure to equalize, which is an important factor in basement flooring renovation and for installation on wood and virgin concrete subfloors. Vapor equalization is vital where risks of humid emission are significant to prevent the formation of trapped water under the membrane. The distinct bone-shaped stud design of the membrane's surface readily accepts thinset mortar adhesive. As the adhesive dries, the undercuts on each stud enhance its grip, boosting adherence and reducing curing time. The studs support and protect the tiles above while improving flexibility and absorbing lateral shear movement. This improves tile and grout joint longevity and saves money on renovation. It is a durable crack-isolating and uncoupling membrane, protecting your floor tiles and other floor covering by preventing potential damage and reducing grout stress from the substrate below. ARDEX UI 740 works with a wide variety of surfaces - linoleum tiles, vinyl flooring, ceramic tile, porcelain tiles, cement tiles, marble tiles, natural stone tiles, granite, laminate flooring, concrete blocks, carpet tiles, existing tile, cracked surfaces, painted floors, and mixed substrates. The ARDEX UI 740, made in Germany, will exceed your DIY home improvement project demands - whether you're installing bathroom tile, shower tile, or building a floor for your bedroom, hallway, balcony, basement, kitchen, dining room, foyer, or any other living area, this uncoupling membrane will live up to the task.

Review: Best membrane! - I’m very happy with the ARDEX FLEXBONE membrane. Having worked with Schluter Ditra before, I can confidently say that ARDEX is much easier to work with. It’s more flexible, lays flat without any need for stapling, and for the price, you get almost twice the coverage compared to Schluter. Great product! Best regards, Max I’m very happy with the ARDEX FLEXBONE membrane. Having worked with Schluter Ditra before, I can confidently say that ARDEX is much easier to work with. It’s more flexible, lays flat without any need for stapling, and for the price, you get almost twice the coverage compared to Schluter. Great product!

## Features

- The ARDEX FLEXBONE UI 740 underlayment membrane. One roll covers 215 Square Feet (20 Square Meters). 1/8" (3 mm) thick. 39" wide (1 m wide), 65.6' long (20 m long). Germany made
- Effective uncoupling action protects your surfaces, tiles, and grout joints from cracking or buckling due to natural movements and changes in the subfloor caused by wetness and temperature shifts
- The unique bone-shaped stud pattern fills with thinset mortar with just one pass, and its grip lock technology creates an extremely strong mortar-to-membrane bond for strong tile adhesion
- Ventilation channels in the FLEXBONE pattern compensate for vapor, and special high performance felt helps provide vapor equalization. It also features waterproofing capabilities
- Take advantage of the FLEXBONE 740's Extra Heavy load bearing rating to protect your tile in high-stress areas (commercial and residential) - shops, restaurants, kitchens, hallways, gyms, offices, foyers, hotels, hospitals, food courts, and other busy traffic areas

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Manufacturer | Ardex |
| Part Number | UI 740 |
| Product Dimensions | 40 x 14 x 14 inches |
| Item model number | UI 740 |
| Size | 1 Roll |
| Material | Other |
| Item Package Quantity | 1 |

## Images

![ARDEX FLEXBONE UI 740 Uncoupling Waterproofing Polyethylene Membrane 215 Sq Ft Roll, 1/8" Thick, Load Bearing Underlayment for Large Format Tiles in Heavy Stress Areas -1 Roll - Image 1](https://m.media-amazon.com/images/I/51Jw91DCjKL.jpg)
![ARDEX FLEXBONE UI 740 Uncoupling Waterproofing Polyethylene Membrane 215 Sq Ft Roll, 1/8" Thick, Load Bearing Underlayment for Large Format Tiles in Heavy Stress Areas -1 Roll - Image 2](https://m.media-amazon.com/images/I/610vfIReSbL.jpg)
![ARDEX FLEXBONE UI 740 Uncoupling Waterproofing Polyethylene Membrane 215 Sq Ft Roll, 1/8" Thick, Load Bearing Underlayment for Large Format Tiles in Heavy Stress Areas -1 Roll - Image 3](https://m.media-amazon.com/images/I/81AL3Y2t7lL.jpg)
![ARDEX FLEXBONE UI 740 Uncoupling Waterproofing Polyethylene Membrane 215 Sq Ft Roll, 1/8" Thick, Load Bearing Underlayment for Large Format Tiles in Heavy Stress Areas -1 Roll - Image 4](https://m.media-amazon.com/images/I/81J-IJyo5FL.jpg)
![ARDEX FLEXBONE UI 740 Uncoupling Waterproofing Polyethylene Membrane 215 Sq Ft Roll, 1/8" Thick, Load Bearing Underlayment for Large Format Tiles in Heavy Stress Areas -1 Roll - Image 5](https://m.media-amazon.com/images/I/81cuXCGsUlL.jpg)

## Available Options

This product comes in different **Size** options.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Best membrane!
*by M***X on October 5, 2024*

I’m very happy with the ARDEX FLEXBONE membrane. Having worked with Schluter Ditra before, I can confidently say that ARDEX is much easier to work with. It’s more flexible, lays flat without any need for stapling, and for the price, you get almost twice the coverage compared to Schluter. Great product! Best regards, Max I’m very happy with the ARDEX FLEXBONE membrane. Having worked with Schluter Ditra before, I can confidently say that ARDEX is much easier to work with. It’s more flexible, lays flat without any need for stapling, and for the price, you get almost twice the coverage compared to Schluter. Great product!

## Frequently Bought Together

- ARDEX FLEXBONE UI 740 Uncoupling Waterproofing Polyethylene Membrane 215 Sq Ft Roll, 1/8" Thick, Load Bearing Underlayment for Large Format Tiles in Heavy Stress Areas -1 Roll
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*Product available on Desertcart Iceland*
*Store origin: IS*
*Last updated: 2026-03-08*