America, have been proven to be very effective at stopping the upward
spread of fire in tall buildings.

which is presumably why sprinklers are AIUI the normal means here of
complying with the BRs for new residential builds over 30m high. But in
a new build house with linked smoke alarms throughout and escape windows
upstairs I still doubt they are cost-effective.

--
Robin
reply to address is (meant to be) valid