If this will be a well used bathroom then you should visit a bathroom showroom and look at the size of shower baths and vanity units- when you know what you want in there you may conclude that you want to reduce the back bedroom size and make the bathroom a little larger

Have you thought about leaving toilet and sink where they are and having the bath turned the other way at the top right corner, with the shower opposite in the new space that is being created? Get a shorter bath if necessary to fit the space - big baths are a waste of space and water and shorter baths are more comfortable unless someone in the house is really tall. Then the narrowest section of walkway is between shower and bath which I think is fine rather than it being narrow to come into. I'd also rather hang my towel on the side of the bath ready for coming out of the shower than anywhere near the toilet - I like toilets to be kept at a distance! Not having to move soil stack will save money and the 'long view' into the room will be bath rather than toilet.

Hi S C, We'd really need a bit more info on window sizes (width & height), placement (including distance from floor) and position & size of doors as well as whether it is hung on the RHS, LHS and opening inwards or outwards to be of any real help to you!

I think your instincts are right and this room is too small for the laundry as well as a bath and shower. I think if you want a jet bath it will be at least 800 wide. If you then have a 700 toilet opposite there will only be 450mm for knees which is not enough. A space saver toilet might help but I still think it will be undersized. Furthermore the wall against the stairs will be tight for everything you want to fit in. If it were me I would prioritise a shower. Even with a laundry in there this could be an amazing shower room - I would then resolve to make sure that every time you go away you book a room with a tub. If you need the bath for toddlers then you should consider an oversized bath with a super shower over it