We are thinking of putting in an offer on a masionette(lower ground and upper ground of old Victorian conversion) which has a downstairs bathroom but none upstairs. We could not live with it like that, but can see scope to put one in.
We talked with our builder and showed him the floorplan. He said he could do it, but would need to add a step to the top of the stairs and raise the entire upstairs floor by 20cm (the rise of the step) and the pipe work would go underneath (all plumbing as at the back of the property and the bathroom would need to go at the front). The flat has really high ceilings so this would not be a problem, but is obviously a major hassle as we would not be able to live there while it was happening as none of the bedrooms would be habitable.
So, are we absolutely insane to be thinking of doing this? The property is a good size and I think this would make it really saleable if we ever decided to move (having two bathrooms with one upstaris).