Manufacturers and contractors are welcome to contribute to the Expert Advice section. Schlüter-Systems have prepared a series of advisory technical articles relating to the ongoing problems associated with movement in floor tile installations. Contract Flooring Magazine leads the way for publishing such expert advice online for reference by the flooring, building and construction industry.
Contract Flooring Magazine articles are read by industries top professionals and decision makers including Architects, Specifiers, flooring and building industry manufacturers.
If you would like to contribute to this section, please contact us.
Read our definitive series on movement joints and why they are needed. We also cover the technical aspects regarding their installation.
Schlüter®–Systems 'Ian Knifton' expert in this field, have contributed a Movement Joint Series of technical articles. A valuable trade resource.
Published your advisory articles yet?
Find out more here: Membership Features
| Article Index |
|---|
| Movement Joints In Floor Tiles - Why, Where and How |
| Joint failure due to different abutting substrates |
| All Pages |
Ceramic and stone tile installations can be subjected to a variety of strains and stresses leading to tiles bulging, cracking, or becoming detached from the substrate.
The correct placing of appropriate stress-relieving movement joints will absorb many of these strains, preventing damage.
Therefore, movement joints are an essential part of any tiling installation and should be incorporated at the design stage. However, most calls to our technical support service from architects, specifiers and tilers relate to movement joint recommendations or application problems.
Amongst the many factors causing ceramic tiles to move, are significant changes in atmospheric temperature, weight loading, traffic density, rigid attachments such as fixed plant, pillars etc., and thermal and moisture movements in the structural base, background and tiling.
Movement joints create a tile field which moves independently from those around it, and should be included at set distances in floor and wall tiles, in accordance with recommendations from the British Standards Institution (BSI). BS 5385 says the maximum tile field should be no more than ten metres in each direction for floors -- but in practice, depending on the application and the aesthetic possibilities, it tends to be between five and eight metres on floors, and every three to four-point-five metres for walls. Because there are specific movement joints for specific types of application, most tiling failures are caused by using joints that are not suitable for what is being asked of them.
A typical installation should include movement joints within the tiled area itself and on internal corners of walls, along with the floor-to-wall connection. They should also be used at the perimeter of applications of over two metres, or where there is excessive thermal and vibration movement. Installers and specifiers should always refer to the BSI recommendations for specific applications.
There are different widths of pre-formed movement joints, and the correct width and material (brass, aluminium, stainless steel and PVC) must be specified to take thermal movement into account, along with traffic density. If the wrong one is specified the installation is likely to fail. The amount of movement that can be absorbed depends on the size of the joint and the compressible material used. Pre-formed surface joints will usually accommodate movement up to 20% of the movement zone width.
Therefore, a 10mm joint will extend and compress by approximately 2mm. Schluter's largest movement joint, the DILEX-KS, which is 15mm wide with a movement zone of 11mm, will accommodate tile movement up to 2.5mm.
Along with the wrong type of joint being specified, other common mistakes include failing to lay a movement joint where the substrate changes. In renovation work, tilers could find they're having to put one tiled surface over two abutting substrates such as timber and concrete.
