by rosebery »
Mon Jun 01, 2009 11:54 pm
If you use anything but the adhesive type that SB suggests the tiles will crack. You must also use flexible grout. Its not a gimmick its doing it properly I'm afraid.
Your most pressing problem, however, is that you are planning to lay them on chipboard. Thats a total no no as grout and adhesive is not totally waterproof and it WILL get underneath and the chipboard will swell etc and the tiles will crack.
In fact if its a suspended wooden floor on an upper floor the floor WILL move with the building. So you need a very stable sub-base for your tiles. At the very least you need 18mm ply screwed down at 150mm centres into the joists over the existing boards. If it were me I'd be ripping up the chipboard and using 25mm ply with additional noggins between the joists where the joins fall. In either case it must be mnimum WBP ply - do not use OSB or you'll have problems downstream. If its on an upper floor I'd also be using a decouplng membrane like Ditra.
Your floor will NOT last otherwise and if anyone asked me to quote for laying porcelain onto chipboard , frankly, I'd walk away from the job.
Sorry to put a dampener on it for you.
Cheers