Best substrate for half height tiling

Hi everyone.
I'm about to embark on a complete bathroom refit (very small bathroom approx. 3.2sqm) that will have a corner shower with full height tiling in 8mm porcelain tiles (approx 100mm across). The remainder of the room will be 9mm porcelain hexagon tiles (approx. 250mm across) up to a height of approx. 1100mm then skimmed and painted above.

All but one of the walls is masonry (after I've stripped off the existing tiles) and I'm trying to determine the best way to prepare the walls for the tilers.

In my mind the options are:

• Marmox or Hardibacker the whole room, dot & dab with dowel fixings method and then plaster above the tiles after they are installed. (marmox is fine to be plastered, not sure on Hardibacker)
• Hardibacker the shower cubicle to full height and dot & dab the rest of the walls with MR plasterboard. Tile bottom half then skim to tile bead.
• Some combination of the 2 with hardibacker on bottom half, MR plasterboard on top (except shower) but I'm concerned about introducing such a joint exactly where materials change from tile to plaster.

Would really appreciate your advice on the best way to do this. I'll have about 3 days to do the lining with at least one helper but other than that restriction my emphasis is on doing right as opposed to cheap or quick.

Hi,

I used Hardibacker and then used a stopbead to plaster to. Then I have a nice clean edge to tile to and put the trim against.

You have to make sure that you get it 100% level before you plaster though so that the tiling is all level.

And the hardiebacker sucks like you wouldn't believe, so plenty of SBR or whatever suction control you decide on.

I'm only DIY so I may be wrong, but seems to have come out well and is well adhered.