What to use for boxing in around sink....under tiles

[kjacko]

Guys,
i'm in the middle of re-fitting our bathroom. I needed to build a box frame so i can back the toilet and sink to this new 'wall' as the soil pipe position doesn't allow them to sit flush to the proper wall.
Question is, what substrate do i use for the frame wall, which will ultimately be tiled?
I've currently part made it with 12mm mdf, but have since read that mdf is a big no-no for tiling onto regardless of what kind of primers you use.
Would 12mm ply be better.
Or would aquapanel be better, although its much more expensive, as i can get off cuts of ply for literally a couple of quid. Obvisouly only the area atop the sink is likely to get wet.

Thanks.

 

[Karis]

Don’t use ply or MDF which is totally unsuitable. In wet area use 12.5mm Aquapanel or other cement based tile backer board; in dry areas you can use 12.5mm Moisture Resistant plaster board. Screw fix over a timber box frame with service access panels as required.

 

[kjacko]

As usual Karis, thanks. How would one go about making an access panel in a tiled fake wall?
Actually i've managed to position all the relevant connections, tap isolators etc in front of the tiled wall but mostly hidden by the sink pedestal etc..
The lid of the wall will act as a shelf but i'm going to put magnetic catches on so its stable but can be removed with enough access to get your arm down the back of the wall should you need to.

 

[Karis]

As usual Karis, thanks. How would one go about making an access panel in a tiled fake wall?

I always make the size of the access panel to either a full or half tile, depending on the size but you obviously have to plan your tile layout! I build a timber sub frame around where I want the access panel, cut the Aquapanel to suit & tile as normal. I usually secure the tiled access panel to the frame with a couple of plastic caped mirror screws but you can use concealed magnetic catches with a bit of imagination.