Yeah, its good practice and well worth doing IMO. Next time you lay a floor, press a tile into the adhesive without back buttering it, then lift it up and have a look at the bck of the tile and then do the same with a tile that has been back buttered. You are trying to get 100% contact on the back of the tile as any voids will end up with cracks in the tiles later on down the line.

how much addy do you apply mate?

If the floor is pretty flat then you should only need to skim the back of the tile with the flat edge of your trowel, it is only so that the 2 wet surfaces make contact and make 1 solid bed of adhesive. If you lay the tile down and it ia slightly low than you can lift it up and apply more but it is very important not to leave and voids.

Hi,

do i need to use any specific screws and washers to screw down the boards?

cheers

paul

the board are to be fitted in a brick bond way the tiles are going vertically (300x450) does it matter if the board go horizontally or vertically?

I'd be fixing right angles to to other joints

so follow the chipboard layout and screw to the joists then at 300 centres?

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