Thanks active builders, I thought 1.8m depth for the wet area - assuming bath is 80cm wide that leaves 1m depth for the showering area, but then that only leaves 1.2m to fit basin and toilet, which I thought might be a bit tight? We don’t really want a small basin as this is the main bathroom. My other option is to have toilet and washbasin opposite each other in the 1.2m run, but then this leaves a 80cm gap between toilet and washbasin and not sure if this would look a bit cramped?

Miriam Do you actually mean columns as in structural elements or do you mean decorative pilasters? The size of a column is dependant on the load it is carrying and if these are load bearing elements. I would consult an architect and an engineer. There are standard sizes but the choice is driven by the structural requirements. If they are pilasters. Then a starting point would be to talk to suppliers of the plaster replica's https://www.lassco.co.uk/a-pair-of-english-cast-plaster-pilasters or others. They should be able to give you some guidance on the choice and size modules. Hope this helps Best David

​I have a 1400 x 800 shower, was going for walk in but bathroom fitter advised against it. We have a sliding door, easy clean, expensive one. I am glad i didn't go for the walk in because honestly 1400 is too small. Why not go for 1600 with a walk in, or 1400 with sliding door. By the way the small gap can he easily sorted by your tilers. They'll make recommendations when they come n to quote. Such a common problem for them to solve. I'll try to attach a pic of my showerso hopefully you'll see that 1400 ight be too small for a walk in.

Ah, @Daisy England, I too am a fan of L-shaped corners - but not in the 900x900 variant, which I find far too awkward to access, as the opening is only 4520ish diagonally. But my main kitchen provider does truly wonderful options in 1030x1030 (2x 400 doors, 570w diagonal) and a whopping 1080x1080 (2x 450 doors, diagonal opening of 650 ish). They are a really great & inexpensive way to kit out a corner and keep everything accessible. Or for compact kitchens my German manufacturer does a really great 800x800 L-shaped carousel unit - great for tight spaces! Caldicot Kitchens