A bathroom is mostly a question of where the water can go, and in Nuneaton the answer depends on the age of the house rather than on where in town it is.
On modern housing the soil stack is internal and a bathroom moves easily. On the Victorian stock it runs on an outside wall, and in the Abbey or town centre conservation areas, where an Article 4 direction may apply to external work, altering a street facing elevation becomes a permission question rather than a site decision. Behind the building line there is far more freedom.
Floors are the second constraint. Victorian upstairs joists were sized for a bedroom, not for a filled bath sitting on a tiled floor. Where a waste run means notching or drilling them there are permitted zones, and the wrong cut in the wrong place is common and serious. We will move a fitting a foot rather than cut a joist where it must not be cut.
Ventilation gets treated as an afterthought and causes years of trouble. An extractor discharging into a roof void puts the moisture straight back into the building. We duct it outside properly.
Tanking is not optional on a walk in shower, because tiles and grout are not a waterproof layer. Our bathroom installations page sets out what a full refit involves.