STANDARDS

AS/NZS 3500 explained: the four parts in plain English

AS/NZS 3500 is the standard that sits behind most of the plumbing work you do, and it is split into parts. Knowing which part covers what makes it far quicker to find the rule you actually need.

What AS/NZS 3500 is

AS/NZS 3500 is the Australian and New Zealand standard for plumbing and drainage. It is the technical detail behind the regulations: how water, waste, and stormwater systems are designed, installed, and tested. In Victoria it is referenced through the plumbing regulations, so working to 3500 is how you work compliantly.

Part 1, water services

AS/NZS 3500.1 covers cold water services: pipe materials and marking, cross-connection and backflow prevention, separation from other services, buried-pipe cover, support spacing, storage tanks, disinfection, and pressure testing. Most of the drinking-water side of a job lives here.

Part 2, sanitary plumbing and drainage

AS/NZS 3500.2 covers sanitary plumbing and drainage: the pipework that takes waste away. Pipe gradients, trap seals, venting, and the rules that keep the drainage system flowing and sealed against smell and back-up.

Part 3, stormwater drainage

AS/NZS 3500.3 covers stormwater: roof drainage, gutters and downpipes, surface drainage, and how rainwater is taken away from a building without overloading or flooding it.

Part 4, heated water services

AS/NZS 3500.4 covers heated water: tempering and temperature-limiting valves, the relief valve and its drain line, safe trays, insulation, expansion control, and commissioning. Most hot water compliance points sit here.

Why the part matters for documentation

A record that names the actual part and clause the work was checked against is far stronger than a vague "all compliant". Elemetric checks job photos against AS/NZS 3500 and records which standards applied, so the part is captured for you. For the cold and hot water detail, see the cold water checklist and full compliance guide.

Common questions

How many parts does AS/NZS 3500 have?

The core series has four numbered parts: 3500.1 water services, 3500.2 sanitary plumbing and drainage, 3500.3 stormwater drainage, and 3500.4 heated water services. There is also a glossary part.

Which part covers hot water?

AS/NZS 3500.4 covers heated water services, including tempering valves, the relief valve and drain line, insulation, and commissioning.

General information for licensed tradespeople, not legal or regulatory advice. The licensed plumber remains solely responsible for compliance. Refer to the current AS/NZS 3500 standards and the Building and Plumbing Commission (formerly the VBA) for authoritative requirements.