In article ,
"Christian McArdle" writes:
Firstly,can I stick plasterboard straight to the wall without bothering
with battons.

Any reason you don't plaster it instead. It would only need scratch
(base) coat, not finish coat if you are going to tile it anyway.

Secondly,can i tile onto this plasterboard.

Yes. However, plasterboard disintegrates when wet. Therefore, you must use a
good quality adhesive and use a full fill technique so that the entire space
behind the tiles is solid adhesive, not just ridges with air gaps that water
can penetrate past, soaking the plasterboard.

I only use adhesives that claim suitability for commercial swimming pools.

I'm not sure any of the tile adhesives are water-tight, even if they
are water-proof. They normally require you to use something like
aquapanel rather than plasterboard, or to tank the plasterboard with
a waterproofer.

--
Andrew Gabriel