The wall was replastered (the entire room was) and painted but because it is a solid wall I did not think it needed to be reinforced in any way to support the weight of the tiles.
It's not a problem Mandy, I'm just trying to do as much research as I can without visiting.
If I can do this then there won't be any nasty surprises when someone turns up to complete the work. What you don't want is someone to say
"Nah can't be done" or " you need to do this that and the other"
So by asking lots of questions, hopefully I can prepare you for what happens next.
Unfortunately, as you are aware,
this is not a case of "Well they're just tiles!"
Which is something we hear a lot.
Take my current project, I have 3.2 x 1.6m pieces, and even cut down and fabricated to size, 50% will NOT go up the stairs.
So preparation is paramount.
The fact that the walls are plastered and painted already rings alarm bells over the suitability of your wall. With weight limits alone, they just fall within tolerance, and I mean just!
The paint at the very least will have to be removed.