Page 16 - Tiling Guide Uniclass Index

10 MOVEMENT JOINTS
Movement joints help absorb the movement in the floor or wall tiling from moderate background shrinkage, heat expansion, contraction or vibration, thus preventing tiles or grout from cracking, and in some cases prevents the tiles from becoming debonded from the substrate.
For Walls
Movement joints should be used as follows:
• Continuous with any existing structural movement joints.
• Where tiling abuts other materials.
• At junctions between different substrates.
• At vertical corners and at 3m to 4.5m centres, both horizontally and vertically, in large areas.
• In areas where stresses are likely to be concentrated such as at changes of alignment.
• An increase in the frequency of movement joints should be considered if large degrees of thermal movement or vibration are expected within an installation.
For Floors
Movement joints should be used as follows:
• Movement joints should extend through the tiling and its bed and coincide with any structural movement joints.
• Around the perimeter of the tiled installation (including door thresholds) with intermediate movement joints being provided in larger areas at 8m to 10m intervals.
• At junctions between different substrates, door thresholds and between existing substrates and new heated screeds.
• On suspended floors stress-relieving joints should be provided over supporting walls or beams where there is a risk of flexing.
• See page 21 for movement joint requirements for tiling with underfloor heating.
• British Standard recommended minimum width for an intermediate or perimeter movement joint is 6mm.
For further advice, consult TTA’s Technical Publication ‘Movement Joints in Internal Tiling’.
An example of movement joint good practice
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