As the concrete cures it generally shrinks.
Tile expansion joint detail.
Recognizing that tile is a facade movement joints are needed to eliminate stresses that can occur between the substrate and the tile due to differing amounts of expansion and contraction.
If you tile over an expansion joint then you need to honor that joint in the tile as well.
It s quite common to see controlled breaks in concrete and those are usually expansion joints.
The sealant used in expansion joints should achieve a minimum shore a hardness of 35.
Possibly the best type of expansion joint material that can be used is a flexible silicone e g.
Schluter systems prefabricated movement joint profiles protect tile edges and prevent sound bridges and surface water penetration resulting in a permanent maintenance free installation.
Joints in the tile assembly will result in callbacks and expensive repairs as well as the subsequent installation of movement joints.
The tcna handbook recommends allowing for expansion and contraction in every tile installation.
A movement joint is in the tile only.
Where should movement joints be placed.
It is best to achieve a two sided bond only to the flanks of the open joint in the tile.
Architectural resources and product information for floor to floor expansion joints including cad drawings specs bim 3d models brochures and more free to download.
Latasil or urethane sealant placed over a closed cell foam backer rod.
Movement joints are an integral part of any tile assembly and must be incorporated within the tile field at doorsills and at transitions to walls and other restraining structures to allow movement of the assembly and prevent stresses that can damage the system.