Tilebacker board

[CG]

I have installed a new bath and shower and are going to tile around the bath and create a shelf at each end and tile the side of the bath all in the same tiles, I have built a timber frame for the bath and have some 10mm Wedi board to tile on.

Should I use 18mm or 12mm ply under this or can I screw the Wedi direct to the timber stud work, will this be strong enough to hold the tiles etc. any good tips on using Wedi board would be much appreciated such as good adhesive or fixings.

I will be leaving an access panel to fix waste etc and just grout in the joints to hide it

thanks in advance

chris

 

[gcol]

I've never used Wedi board but I would imagine for the size of panel you're going to be using it should be fairly rigid. If you've got a timber frame that will support the Wedi board around it's perimiter it should be ok as it is. Can you not cut the sheet to size and offer it up and see if there's any movement in the sheet if you apply pressure to the middle of it? If there is, just add a sheet of 12mm WBP ply under it.
Personally I'd glue it down rather than screw it. Use a decent grab adhesive. B&Q do a "Cerafix Grabs Like Nails" that's ok. If you can find "Evostick Sticks Like Sh*t" that's good stuff too.