Three responsibilities, one building
The owners corporation covers common property: lobbies, lifts, stairs, corridors, bin rooms, car parks and shared amenities. A landlord within a lot may be responsible for areas outside a tenant's demise, such as a shared kitchen serving two tenancies on one floor. Each occupier covers its own premises. On paper that is clear; in a converted building with irregular layouts it frequently is not.
The seams are the problem. A corridor serving two tenancies, a shared washroom on a commercial floor, a rear service passage, a loading area used by the ground floor venue and a bin room shared between residential and commercial users. Each is arguably somebody's, and each is regularly attended by nobody because the parties assume the other's contractor covers it. Rear service passages are the most common of these, since they serve everyone, are seen by nobody and appear in no scope until a fire inspection mentions them.
