What thickness of tile is recommended
It depends on your floor base, for timber floor we highly recommend 20 mm thick board and that's because of floor boards' thickness. With proper installation they can be simply replaced. Please see our fitting instructions for more details.
Only real difference between each thicknesses is the slope. Thicker shower tray is steeper at the same time. It might be beneficial to prevent water from getting outside shower area if you think you will have plenty of water running through your shower, however the most important thing to achieve is to have tray flushed with rest of the floor level.
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