confused.com

**davebates** · 19-08-2011

hi guys its late and ive confused myself a bit ive got a kitchen/diner to tile the diner side is floorboards (quite solid) but still floorboards and the kitchen side is a really uneven concrete slab its in the same room so tiles will run across both sustrates, so the question is do remove the floor boards and go 15mm wbp across the joist then 6mm hardi,s then pour 2 buckets of leveller on the concrete side to bring it true and flush with hardi boards or do i leave out the the hardi and ditra over the ply. Will i need to ditra over the joint between the two substrates ?? please can some one point me in the right direction ta muchly !!!

**davebates** · 19-08-2011

forgot to mention tiles will be ceramic or porcelain not stone

**Mike** · 19-08-2011

i can't see any need for ditra there but after levelling the concrete side and strenghthening the floorboards you will need to have a transition/grout joint between the 2 substrates. i've done similar using coloured silicon to match the grout

**davebates** · 20-08-2011

right ok would you make sure a tile joint was across the changed in substrates then ?

**Mike** · 20-08-2011

yes, thats it dave

**peteablard** · 20-08-2011

Originally Posted by Mike

i can't see any need for ditra there but after levelling the concrete side and strenghthening the floorboards you will need to have a transition/grout joint between the 2 substrates. i've done similar using coloured silicon to match the grout

I did exactly the same this week, opus pattern floor that went into a new extension. Got matching Mapei silicone to use as a movement joint across the doorway