Hyrax4978
REGISTERED
In CT per 1019.3 stairs between stories that are not enclosed (that meet exit travel distances) are allowed to be unenclosed only if serving less than ten occupants. If you can maintain all travel distances to first floor exits, and have openings between a first floor and second floor for other purposes (common air), why do you need rated stair enclosures? Again, assuming we meet travel distances from all areas of the second floor, down the diagonal stair plain to an exit, as far as i can tell in CT you would need to rate the enclosure if it serves more than ten occupants.