I have a 4-storey building which originally had 2 passenger lifts. One lift has been removed and the openings to each floor have been sealed to provide horizontal compartmentation to the lobbies on each floor. My question is, would it be expected that vertical compartmentation should now be installed in the redundant shaft or does it suffice to have a smoke detector at the top of the shaft? My own feeling is that if there are any live electrical services within the shaft that it should be vertically compartmented?
