floor tiling Advice and information on tiling and fixing tiles to a variety of surfaces

[westie1961]

hi all, we were going to get someone to tile the bathroom floor, its an upstairs bathroom and it has a solid chipboard type floor, the boards interlock with each other. its approx 1inch thick and very dense. i know cos we had to have a ligh fitting moved and i told the sparky i would remove the upstairs floor boards. ( big mistake).

any how, should we board the floor, or remove whats their and put new wood down to support the tiles. The latter ption seems better as it means we wont raise the level of the floor.
alos we want to turn the bath around so need to re route the water pipes that are under the floor.

i want the job, to last.

[plumbbob]

If the existing floor is sound and fixed down properly, there is no need to change or remove it. changing floors, because of the cuts required, often actually weaken it, and that makes the tiles more likely to fail.

Read the tiling instructions, and it will tell you to put another layer of 18mm exterior plywood down to make a suitable base, but I have never seen this done on any job I have worked on. Generally, it is accepted to ensure existing boarding is in good order and firmly fixed down. Fix a new layer of 6mm exterior plywood down screwed every 6". Tile over using two part flexible adhesive (powder and milk (not water)). Allow to dry for at least 24hrs with no traffic. Grout with flexible grout.

The plywood ensures a level even base, and allows you to remove the tiles at a later date without damage to the original floor.

Look at these topics.

https://www.diydoctor.org.uk/forums/viewtopic.php?t=9178

https://www.diydoctor.org.uk/forums/viewtopic.php?t=8804