Where I did my PhD, typically two PhD students shared an office room. In constrast, where I am working as a postdoc now, about 50 PhDs and postdocs share an open-plan office.
I find it difficult to concentrate in the latter kind of arrangement because of the noise. Some people use head/earphones, but I guess not everyone likes to listen to music while working. I am wondering if this is a common arrangement in academia. My guess is that while it might work elsewhere, the nature of academic research precludes an open-plan type of office.
In any case, is it appropriate to ask my supervisor for a room or a smaller/quieter space to work in? I don't think I would ask, though, because everybody else seems to be fairly content, but I'm just wondering.