The time to find out where the water problem/issues are present is during and after the long term wet.
Just some of the factors related to the NCC, (portions shown)
Performance P2.2.2 Weatherproofing
Good heavy and consistent rain, brings out the best and worst in buildings. It best to find out now if the roofs, balconies, windows and general storm water are working as to codes and as would be expected. It clear in the (NCC) National Construction Code. Volume 2 relating to Requirements’ Section
A roof and external wall (including openings around windows and doors) must prevent the penetration of water that could cause— (a) unhealthy or dangerous conditions, or loss of amenity for occupants; and Part 2.2 Damp and weatherproofing Explanatory information:
Functional statements F2.2.1 Surface water.
A building including any associated sitework is to be constructed in a way that protects people and other property from the adverse effects of redirected surface water. F2.2.2 Weatherproofing and dampness A building is to be constructed to provide resistance to moisture from the outside and moisture rising from the ground.
Limitation: F2.2.2 does not apply to a Class 10 building except where its construction contributes to the weatherproofing of the Class 1 building.