Surface water from a storm with a 5% annual exceedance probability that a building or its sitework collects or concentrates must be disposed of without likely damage or nuisance to any other property, and surface water from a 1% annual exceedance probability storm must not enter the building. The drainage system must carry the 5% storm to an appropriate outfall without damaging the building and keep the 1% storm out of the building. H2P1(2) binds a Class 10 building only where its construction helps weatherproof the Class 1 building. Deemed-to-Satisfy route: H2D2 drainage to AS/NZS 3500.3, or, where the stormwater system otherwise complies with it, Housing Provisions Part 3.3 for roof drainage in areas where the 5-minute, 5% rainfall intensity is not more than 255 mm per hour, subsoil drainage and land adjoining and under buildings; H2D6(1) to (3) gutters and downpipes to AS/NZS 3500.3 or to Housing Provisions Part 7.4 (not box gutters, and only if connected to a stormwater system complying with H2D2); the 1% storm requirement need not apply to a Class 10 building where there is no need in the particular case. Victoria allows only AS/NZS 3500.3 for gutters and downpipes; Western Australia (Amendment 1) varies AS/NZS 3500.3 clause 3.5.1 and Table 3.5.2 for eaves gutter overflow and downpipe sizing.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.