Tile/Tile Backer Under Bath

[brooks693]

I've just lay a new 18mm plywood floor in what will become the bathroom. It is only a small room (1.5m square), and the Bath will take up a large amount of this room. What floor there is exposed I was going to lay ceramic tiles on, but should I tile under the bath? Seems a waste to. If not, should I still lay the tile backer board over the whole floor, or just the area to be tiled. Cheers

 

[freddiemercurystwin]

Its good practice to tile over the whole floor and will hardly break the bank.

 

[geraldthehamster]

I've just lay a new 18mm plywood floor in what will become the bathroom. It is only a small room (1.5m square), and the Bath will take up a large amount of this room. What floor there is exposed I was going to lay ceramic tiles on, but should I tile under the bath? Seems a waste to. If not, should I still lay the tile backer board over the whole floor, or just the area to be tiled. Cheers

I wouldn't tile under the bath, personally. It's a waste of tiles and effort. It will be less faff to fix bath legs to the floor if it isn't tiled. Ditto if any of your plumbing comes in through the floor, or if the bath waste exits through it.

Cheers
Richard

 

[brooks693]

That's what I had thought. Over half the floor area is covered by the bath so seems pointless to Tile it all. Would you lie the cement board over the whole floor though?

 

[geraldthehamster]

That's what I had thought. Over half the floor area is covered by the bath so seems pointless to Tile it all. Would you lie the cement board over the whole floor though?

If this is a floorboarded floor, you want to be fixing 18mm plywood over it, and tiling on that - not cement board (I assume you mean something like Hardie Backer board, which is designed to go on walls). The idea is to stop the floor moving under the tiles. Less important under the bath, though you might want something to spread the load under the feet.

Cheers
Richard

 

[brooks693]

The floor is currently 18mm plywood direct onto the joists. There is some 6mm board designed to go on floors.

 

[geraldthehamster]

The floor is currently 18mm plywood direct onto the joists. There is some 6mm board designed to go on floors.

Sorry, you did mention you'd already fitted ply. You don't want cement board on top of that, though.

Cheers
Richard