WHY SHOULD YOU INSTALL MOVEMENT JOINTS IN SWIMMING POOLS? Fred Gray, Technical Services Manager, LATICRETE
A tiled interior is one of the most sought-after and aesthetically pleasing finishes that can be installed in a swimming pool, so it’s tempting to avoid anything that may interrupt or distract from the appearance of the tile installation.
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or many residential pools without joints in the structure, this translates into excluding movement joints altogether or only installing them where they can be readily concealed. The omission of movement joints is generally more prevalent in residential, backyard-type pools than larger commercial pools, in which there’s more at stake if movement joints have been deleted or not installed correctly.
Structural movement It’s a basic fact of life that, in the world of structures, everything moves. Accommodating this movement prevents materials from suffering destructive failure. This same principle applies when it comes to ceramic tile and stone installations and swimming pool structures. Movement is a natural part of these installations and must be accounted for and accommodated. In AS3958.1-2007, the guide to the installation of ceramic tiles, Appendix E - Wet Conditions (Continuously Immersed) was
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included for the first time. From 2007, swimming pool tiling was included in the tiling standard. Section E2.10 says that “movement joints should be incorporated in the pool linings” and has specific advice about the installation of movement joints in swimming pools. It also covers movement joints around the pool structure and coping. Water-retaining structures like swimming pools and water features are generally no different to other structures with regards to structural movement. They are also subject to, among other things: • movement from thermal loads • moisture content changes • drying shrinkage • deflection Subsequent tiling systems and many other swimming pool interiors are also subject to these types of movement, and any resulting differential movement between the tiling system and the structure can be very damaging if not accommodated.
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