Study into mixed prison expansion

Study into mixed prison expansion

A study is under way into the possibility of housing another 240 inmates at Peterborough's mixed prison.

I am puzzled why there needs to be a study into this issue. You either have the room to build another wing or you don't it's as simple as that. I would also question the term mixed prison. My understanding in Sweden is that both sexes mix freely within a prison whereas over here the sexes are kept apart.