Plumbing and drainage, Part 3: Stormwater drainage

This Australian Standard specifies requirements for materials, design, installation and testing of roof drainage systems, surface drainage systems and subsoil drainage systems to a point of connection.

This Standard can be used as a means of demonstrating compliance with the requirements of the National Construction Code (NCC).

What's included

AS/NZS 3500.3:2021 contains ten sections:

• Section 1: States what the standard covers, and describes the terms and abbreviations used in this standard.
• Section 2: Specifies requirements for materials and products for use in a stormwater drainage system.
• Section 3: Specifies methods for the design of roof drainage systems.
• Section 4: Specifies installation requirements for roof drainage systems.
• Section 5: Specifies methods for the design of surface water drainage systems.
• Section 6: Specifies installation requirements for site stormwater drains for conveyance of stormwater from roof, surface and subsoil drainage systems.
• Section 7: Specifies requirements for ancillaries of surface water and subsoil drainage systems.
• Section 8: Specifies requirements for pumped systems.
• Section 9: Sets out a method for testing downpipes within buildings, site stormwater drains and main internal drains under buildings and all rising mains.
• Section 10: Specifies design, materials and installation requirements for siphonic roof drainage systems.

This Standard also contains four normative and eleven informative appendices:

• Appendix A contains a list of normative documents referenced in this Standard.
• Appendix B contains information on site-mixed concrete for minor works.
• Appendix C sets out guidelines for the use of network utility operators, to indicate the information that may be included in stormwater drainage installation plans.
• Appendix D sets out guidelines for determining the rainfall intensities for any site in Australia and New Zealand.
• Appendix E gives 5 min duration rainfall intensities for representative places in Australia.
• Appendix F gives 10 min duration rainfall intensities for any place in New Zealand.
• Appendix G sets out examples of overflow measures for eaves gutters.
• Appendix H sets out an example that illustrates the application of the general method for design of solutions for eaves gutter systems and associated vertical downpipes.
• Appendix I contains general method, design graphs and illustrations for box gutter systems.
• Appendix J sets out examples that illustrate the application of the general method for the sizing of solutions for box gutters.
• Appendix K sets out examples that illustrate the application of the nominal method and the general method for the design of solutions for surface water drainage systems.
• Appendix L contains an example of the calculation for pumped systems.
• Appendix M provides guidance for the design of subsoil drainage systems.
• Appendix N provides additional information to users of the Standard.
• Appendix O contains information on the operation of siphonic roof drainage systems.

This Standard is referenced in Part F1D3 Stormwater Drainage of the NCC Volume One and Parts H2D2 Drainage, and H2D6 Roof and Wall Cladding for NCC Volume Two. It applies to stormwater drainage requirements in all classes of building.