We are hoping to do an extension, which will involve making an upstairs family bathroom.
Current bathroom is downstairs, off the kitchen, so planning on making into a utility room (although likely just with tumble dryer and units rather than washing machine-as it is has a well designed space in the kitchen, but we could move it if there was space) but would like to keep a downstairs loo (will also have 1 on 1st floor in family bathroom & one in ensuite in loft conversion)
The room is 1.8x 3.1m and we have a door at one end (on the left) and planning on putting an entrance to understairs cupboard at the other end (on the right) -as currently access is awkward as we have to move sofa in living room, and there is a window along the right hand wall
If we put a separate room in for toilet it would restrict available space, but husband thinks we shouldn't have toilet just in the room, it should be sectioned off. I keep seeing houses that have combined utility/toilets and personally prefer having the sink in the same room as the toilet without a door in between.
Would having a toilet in the same room as utility be a deal breaker for people? Should I just suck up losing 1/4-1/3 of the space for this, or can it be done? Thanks 
Not putting door at other end is an option, but we like the idea of the cupboard being more accessible.