Our house is full of cavity sliders. Twice they were all (but one) replaced due to swelling/warping and rubbing against framework when opening and closing. Some made terrible noise whenever we opened or closed them. Hubby had a hunch they were poorly manufactured overseas and discovered that was the case. Builder sourced a local manufacturer and the whole lot, bar one, was replaced and we haven't had any further issues. The one door couldn't be replaced due to it's location - a wall would have had to be pulled down, just as co-design has described. This experience makes me think it may be a case of ensuring you purchase well manufactured doors for your climate and particular environment, and take into careful consideration the particular location they will be installed.

My thoughts for what they are worth. Can the window be cut down in width and if needed increased in height so the sill finishes at the bathtub hob level, if not leave the sill height as is. I have allowed for a 1650 long x 750 wide with a 75mm tiled hob surround. You have a; 1400 long x 1050 wide shower. 1425 long Vanity. If you want wall cabinets either side of mirror they can be recessed into the existing wall frame (if the wall is framed) and mirror can continue across cabinet doors. If the wall is solid brick/block you have room to build out a wall frame anyway. I'm a bit short on time to explain much more but hope this may help as another option.

we dont Have much to go on at the moment unfortunately - only the floorplan above. From the floorplan it appears that the laundry powder space shaded blue is 3.7 in width. Unsure about other dimensions at this stage. The wall with the door leading outdoors is brick. Unsure about toilet dimensions/ construction. Floors are tiled. As for the family room, it will be one of the most heavily used rooms. And we are looking into renovating the kitchen (with the intent of keeping the same footprint). apologies for the limited details - that’s all we have at this stage. Thanks.

Forget that comment. I see siriuskey has already changed it to avoid that happening. In my bathroom reno at previous house, I had the mirrored storage cabinets above the vanity and toilet and they were so useful. Highgrove bathrooms has some lovely ones IMO. Make sure you buy an off the rack one and then get the wall frame/studs designed to hold it. It works out so much more expensive, getting a customer made mirrored cabinet to fit into a wall cavity. Because the mirrored overhead cabinets were put in the wall cavity, there was no issue with banging your head when you leant over to brush teeth, wash face etc. If the mirrored cabinets went across the whole section of toilet and vanity, you would hold a lot of things in it and it wouldn't matter how small the vanity was because you will be able to store so much in the overhead cabinets. Just be sure that it is deep enough to hold toilet rolls etc. I also got a wall socket fitted into the cabinet so that I could charge things like toothbrush etc whilst they were in the cupboard. It gets more complicated when you are trying to fit powerboards into drawers (well it was for me, so I didnt end up doing it).