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The Plumbing Code of Australia: Everything You Need To Know

When it comes to the safety and functionality of your home, few things are as crucial as your plumbing system. A well-designed and properly installed plumbing system is essential, from delivering clean water to disposing of waste efficiently. That’s where the Plumbing Code of Australia comes into play.

So, what exactly is the Plumbing Code of Australia?

It is a rulebook that outlines the standards, requirements, and best practices for plumbing installations. Similar to other countries, Australia has its own unique set of codes tailored to local conditions and needs. These codes cover various aspects of plumbing.

This article will provide you with essential insights into the Plumbing Code of Australia. Read on to gain the knowledge you need as a homeowner.

Purpose of the Plumbing Code of Australia

The Plumbing Code of Australia (PCA) serves a crucial purpose in ensuring the safety and functionality of plumbing systems. It also ensures the sustainability of the systems in residential properties across the country. This code is part of the broader National Construction Code (NCC).

It sets out the minimum standards and requirements for plumbing installations. The code aims to protect public health, conserve water, and maintain the integrity of plumbing systems.

purpose of the plumbing code of australia

An In-depth of the Plumbing Code of Australia

It is impossible to cover every code detail within this write-up. Instead, we will explore some of its key points to provide an in-depth understanding. They include the following:

1. Health and Safety Considerations

Under this subcategory, we have the following principles:

  • Water Quality and Sanitation: The PCA emphasizes the need for clean and safe water supply systems. It sets standards for water quality, ensuring that it is free from contaminants and safe for consumption.
  • Backflow Prevention and Cross-Connection Control: The reversal of water flow from a plumbing system back into the main water supply poses a significant health risk. Use appropriate backflow prevention devices, such as check valves and backflow prevention assemblies.

2. Water Supply Systems

The following main principles must be fulfilled here:

  • Water Storage: Tanks must be of the highest quality and safety. They should be away from sunlight and other extreme weather conditions. These regulations aim to prevent the growth of bacteria and maintain water quality.
  • Water Supply Lines: Proper installation techniques are mandatory. The installations must be free from leaks and water wastage. They must not pose potential damage to the overall plumbing system.
  • Fixtures and Appliances: Appliances such as faucets, toilets, showers, and washing machines must have proper connections, sealing, and water-saving features.
  • Water Pressure: The pressure must not be too little or over the limit of 500kPa to prevent pipe bursts, leaks, and damage to plumbing fixtures. Each installation must have pressure-reducing valves to maintain consistent water pressure throughout the property.

3. Sanitary Plumbing Systems

These are responsible for the safe and efficient removal of wastewater from residential properties and must meet the following:

  • Pipe Sizing: The PCA specifies requirements for sizing drainage pipes based on the anticipated flow rates and fixture usage. Proper pipe sizing ensures that wastewater is efficiently transported through the system without causing backups or slow drainage.
  • Slope: The slope should be carefully calculated to prevent solids accumulation and promote self-cleaning within the pipes. The minimum fall grade is 1.65% in the country.
  • Material Selection: You must select the appropriate materials for drainage pipes, traps, and vents. These materials should be durable, corrosion-resistant, and suitable for the intended application to ensure the longevity and functionality of the drainage system.
  • Vent Pipe Installation: Vent pipes must be part of your sewer to release trapped air and sewer gases. The pipes must be in the right location and of the correct sizing to prevent gurgling drains and foul odors.

4. Hot Water Systems

Here are the codes and principles for hot water systems:

  • Temperature Control: Thermostatic mixing valves or temperature-limiting devices must be present to prevent scalding accidents. These devices ensure that hot water is delivered at safe temperatures.
  • Pressure Relief Valves: Hot water systems are subject to pressure fluctuations. The PCA mandates the installation of pressure relief valves to manage excess pressure within the system. These valves help prevent system failures, such as burst pipes or tank explosions.
  • Insulation: Proper insulation of hot water pipes and storage tanks is essential. It minimizes heat loss and improves overall system efficiency.

5. Rainwater Harvesting and Greywater Recycling

Below are the principles associated with rainwater and greywater:

  • Non-Potable Uses: The regulations focus on utilizing rainwater for non-potable purposes. These include irrigation, toilet flushing, and laundry.
  • Greywater Separation: There should be a separation of greywater from blackwater and wastewater from toilets. This ensures that only suitable greywater sources are collected and treated for recycling. Specified greywater sources include wastewater from dishwashing, laundry, or bathing.

6. Gas Installations and Safety

Here are vital codes and principles for gas installations and safety:

  • Emergency Shut-Off Devices: Emergency shut-off valves or switches should be near gas appliances. This allows immediate gas supply isolation during an emergency or gas leak detection.
  • Ventilation Systems: You should install ventilation systems to remove combustion byproducts, such as carbon monoxide. This will ensure adequate air exchange.

7. Compliance and Inspections

As for inspections and compliance, the code dictates the following:

  • Building Approval: Before starting any plumbing work, obtaining the required building approvals from local authorities is crucial. These approvals ensure that the proposed plumbing installations meet the standards, codes, and regulations.
  • Certificates of Compliance: A licensed plumber is responsible for issuing a Certificate of Compliance once the plumbing work is completed. This certificate proves that the plumbing installation complies with the PCA and associated regulations.
  • Routine Inspections: For the best longevity, you should ensure your systems are inspected by a qualified technician routinely.


Here are answers to additional questions you may have:

Q: How Can I Stay Updated on Changes to the Plumbing Code of Australia?

Regularly check for updates from the National Constructions Codes website. You might also stay in the loop by attending industry seminars, workshops, or conferences. These can provide valuable insights into any changes or updates to plumbing regulations.

Q: What are the Penalties for not Complying with the Plumbing Code of Australia?

The specific penalties depend on the nature and severity of the violation. For instance, engaging in unlicensed plumbing work or supervising such work can result in penalties of up to 250 Monetary Penalty Units (MPU) for the first offense and 300 for the second. Repeated offenses or instances of grossly defective plumbing work lead to 350 MPU or imprisonment for up to one year.

Q: Can I Perform Plumbing Work Myself Without Hiring a Licensed Plumber?

No. The regulations outlined require plumbing work to be carried out by licensed plumbers. Licensed plumbers undergo training and certification to ensure they have the necessary knowledge and skills.


The Plumbing Code of Australia is a comprehensive framework that sets regulations and standards for plumbing systems. It covers various aspects such as water supply, drainage, gas installations, and rainwater harvesting.

Compliance with the code is crucial to ensure plumbing installations’ safety, efficiency, and environmental sustainability. As a homeowner or licensed plumber, you play a vital role in upholding these standards. Following the Plumbing Code of Australia can create safer and more sustainable living environments while safeguarding public health.