What to replace floor boards with to tile to?

[Mark A]

I want to tile my newly entended kitchen floor. At the moment it's a suspended wooden floor made of 2" strips of wood.

I need to replace these strips with something more stable to tile onto and was wondering what thickness of ply i can get away with putting down directly onto the joists to tile to?

Do i need two layers of thinner ply to cross lay the joins or is one layer of thick ply sufficient?

Thanks

 

[masona]

I want to tile my newly entended kitchen floor. At the moment it's a suspended wooden floor made of 2" strips of wood.

Not sure what you mean by 2" strips of wood.

Do i need two layers of thinner ply to cross lay the joins or is one layer of thick ply sufficient?

The problem would be the floor level will be a lot higher and plus the tile adhesive with floor tiles. The way I do it, is to remove the floorboards and check the condition of joists etc and put down 18mm exterior plywood with screws.

 

[Mark A]

Thansk Mason A.

Basically instead of being 5 or 6" wide by 21.5mm (7/8ths?) floorboards the floor is made up of lots of 2" wide pieces of wood by 21.5mm. They're quite warped and flex and rock about a lot so i was going to replace them.

Is 18mm ply thick enough to be sturdy enough to tile onto?

I've kind of given up on getting the floor level in the kitchen the same as the other rooms as i'd have to go down to 10.5mm (9mm) ply as the floor to achive this. (21.5mm-9mm tile-3mm adhensive)

 

[Washboy]

Straight on joists , I use 25mm tongue and groove ply; stagger the sheets(brick bond pattern) screwed every 4-6 inches