Pretty rare for all the toilets on a rootes floor to be vomited in by many people.
If someone gets drunkill chances are the others on the floor are going to take them home.
The floor would have to be pretty hardcore to have many people throwing up all over the place.
I would advise to approach a possible year in Rootes with a fairly relaxed attitude to cleanliness (and indeed a relaxed attitude to everything)
Mind you you should be aiming for that wherever you are staying.
Its only one year after all.