gs (/wiki/Dwelling), for external tapered stairs (/wiki/Stairs) that are part of the buildings, the going should be a minimum of 280 mm. For existing buildings, alternatives may be proposed if the dimensional constraints (/wiki/Constraints) do not allow these requirements to be followed. There are more complex requirements for stepped gangways in assembly (/wiki/Assembly) buildings, and there may be conflict between these requirements and sight lines in some buildings with spectator seating. Buildings