Floor Preparation and Adhesive

[matthew_uk_666]

I am about to start tiling my bathroom floor and would like to get the pro tilers opinion of the floor preparation and adhesive choice before I get going and stick the tiles down.

The floor is a 22mm T&G chipboard floor glued and screwed to the joists/noggins around all edges, this has been over boarded with 12mm WBP plywood screwed down 150mm in every direction and will have an Impey TileSafe membrane put down covering the whole floor. The floor also has a wet underfloor heating system installed below the chipboard.

I have been advised by the chaps at tile giant that Mapei Keraquick with the Latex Plus would be best option for the adhesive however the Mapei support folks say that without the BS 15mm plywood they cannot guarantee it.

Any thoughts on this would be appreciated….

 

[peteablard]

Was the chipboard deflection free? If so hardie backer would have been better to overboard with IMO

 

[White Room]

Hardie backer for me also.....

 

[matthew_uk_666]

The chipboard was deflection free and with the added 12mm of plywood the floor is extremely firm under foot.

What would the hardie backer give me that the plywood doesn't ?