My gym has replaced the sign on the women's changing room door to 'female changing room'. This really annoys me, as my immediate thought is 'the changing room is a woman? Who knew?'. (Then, I go down a path of troubling moral ambiguity asking whether, as the changing room is female, I need her consent to use it?...) Anyway, I know that female can be used as a noun or as an adjective (although I personally HATE seeing it used as a noun). But, if we assume that in this context 'female' is used as a noun, would it not be grammatically correct to write "females' changing room"? Yet, this sounds ugly. So what is good grammar here? Does female used as an noun assume possession, like the pronouns 'her' or 'its'? And if it does, would it still need to be plural in this instance?
People who know English, help me out, please?