My bathroom floor

[Yukster]

I am planning to replace my floorboards in my bathroom with slate tiles over polywood boards. Is polywood the best material?

If polywood is the way to go, I'd like the board used waterproof to prevent damage if a bit of water gets under tiles. Do I treat the polywood to make it waterproof? what else can I do?

 

[Richard C]

You’re sort of on the right track but it can be a lot more involved & if you fail to get it right or the floor isn’t completely rigid, your tiles will fail. What are your current floorboards made of? What sort of condition are they in? What size/weight are the slate tiles?

Plywood must be WBP (exterior grade), 18-25mm depending on your joist size/pitch/span, acrylic primed/sealed on the reverse side & edges; DO NOT prime/seal the top surface your tiling onto. Fix into the joists with screws (not nails) every 150mm & any board joints must be supported with noggins & taped; flexible powder cement adhesive only on floors not tub ready mix. The type of adhesive you use is also very important, use only quality trade materials of the correct type for your tiles, the cheap DIY stuff is mostly crap.

Have a good read through the Tiling Forum Sticky & archive threads, lots of info in there to give you some idea what’s involved & it may prevent you making disastrous & potentially expensive mistakes; post the tiling forum with any specific questions you have.

 

[Yukster]

My current floorboards are made of pine, some Victorian, some new. Unfortunately, the floorboards are of different width as well but all 18mm thick. The all seem sound and nailed to the joists. The joists are 170x50mm and they are spaced 35 cm apart.

The slate tiles are 300x300x10mm (W L T). I cant find information about how much they weigh so I included a link to the B&Q site that sell them. http://www.diy.com/diy/jsp/bq/nav.j...ationsSpecificProductType=natural_slate_tiles