With most old houses walls and floors are not straight and perfect, however wall tiles can go some way concealing this. I don't know if a reputable tradesperson will fix glass panels to old tiles and be happy to guarantee the job. Seems like an ideal opportunity for mould growth between the old tiles and the new glass if any shower water gets an opportunity to seep around the edges or joints of the glass. I think you may be surprised just how much this type of glass costs to install, and you would probably be better off doing the job properly with new tiles and a proper waterproof membrane as required by the building regulations (which your old shower recess doesn't have). In the future your potential new buyers will probably appreciate a freshly renovated bathroom that conforms with the current building regulations (with standard tiling) rather than a glass panel over mould in a bathromm that doesn't comply with the regulations. Best of luck, Dr Retro of Dr Retro House Calls

Bigger should not cost more. Size does not determine price. I would go for the largest available tile in a shower. Alternately, you could look at wall sheetings like Mr Wet Wall, Spa Panel, Reflections, etc. Much cheaper than tiles due to the labour saving (and in many cases no need for a wall lining under the finished sheeting). There are some lovely designs. They are generally warrantied for 10 years+. And they make cleaning far easier. Personally, I would NEVER have tiles in a shower if building again.

We have 600 x 600 tiles in our bathrooms, one of which is a similar size to yours. I love the look, but we did place the cut tiles on either side which was a little more work, but had a better balance for our bathroom, in our opinion. So much of this is, as Aus Joinery Kitchens said, personal choice. If it jars with you, it’s not for you, but if you’re just worried it’s not ‘standard’, I’d say don’t worry.

Yes please, more explanation. I remember something about weight too, the less framing the heavier the glass the stronger the attachment points need to be? Happy to be be corrected on that.