NCC 2019 (Plumbing Code of Australia)

The National Construction Code 2019 commenced in Victoria on 1 May 2019.

The National Construction Code (NCC) provides the minimum necessary requirements for health and safety, amenity and accessibility, and sustainability in the design, construction, performance and liveability of new buildings (and new building work in existing buildings) throughout Australia.

NCC plumbing FAQs

This page contains answers to plumbing questions taken on notice during our National Construction Code 2019 Seminar Roadshow.

The Victorian Building Authority’s current phone tree focuses on supporting the Victorian community and, in particular, the plumbing and building professionals registered or licensed with the VBA. The voice messages assist callers to get to the right team at the first point of contact.

There are dedicated plumbing options embedded in the design for licensing, auditing or technical information. There is also a dedicated landline for plumbers who undertake underground drainage work, allowing them to communicate directly with the VBA’s plumbing audits team.

Thank you very much for taking the time to share your feedback. The VBA will certainly consider it for any future design upgrades of our telephone services.

The replacement of any gas appliance involving reconnection to an existing asbestos cement (AC) flue is prohibited. When an existing AC flue is identified, it cannot be re-used. This applies even when the flue remains intact (that is, it has not been moved, disturbed or cut into). The re-use of any product containing asbestos is prohibited under the Occupational Health and Safety Regulations 2017.

If you have any questions about the requirements for dealing with asbestos, please contact WorkSafe Victoria on 1800 136 089.

The new noise requirements, which apply from 1 May 2019, are triggered whenever plumbing or drainage systems are installed in a separating wall of a class 1 building or in any class 2, 3 or 9c building that is required to be sound rated.

The requirements apply to both new and existing buildings. These requirements were previously set out in Volumes 1 and 2 of the National Construction Code (NCC) (known as the Building Code of Australia), but are now also listed in NCC 2019 Volume 3 – Plumbing Code of Australia at Part D1 – Excessive Noise and Schedule 1 – Victorian Variation.

Downpipe spacings are determined by the roof catchment area, average rainfall intensity, cross-sectional area of the gutter and downpipe size.

There is no specific measurement for downpipe spacing due to the variable roof catchment area at each site. For more information, refer to AS/NZS 3500.3 Plumbing and drainage – Part 3: Stormwater drainage, Appendix H and G, or VBA Technical Solution Sheet 0.04 – Roof Plumbing.

Plumbers carrying out gasfitting work on gas appliances have a duty to ensure that appliances are not left in an unsafe manner. Regulation 21 of the Gas Safety (Gas Installation) Regulations 2018 requires the gasfitter carrying out the gasfitting work to take steps to make the gas installation safe and to notify the owner of the defect.

Where it is unreasonable for the gasfitter to make the gas installation safe (such as the owner refusing the rectification or isolation of the appliance), the gasfitter must immediately notify Energy Safe Victoria on 1800 665 362.

As a regulator, the VBA cannot recommend any product or manufacturer, as this would be perceived as endorsement and can create a conflict of interest. It is the responsibility of the plumber to choose equipment that is fit for their purpose and their needs. The VBA and ESV do, however, recommend the use of probe type CO testers that are not affected by high temperatures when placed within heat streams.

Visit the ESV website for further information on CO testing equipment.

The VBA does not test the functionality of CO testing equipment available on the market and cannot recommend any particular product. We recommend plumbers carry out their own research to ensure the device they are purchasing is fit for purpose and appropriate to their needs. Visit the ESV website for further information on CO testing equipment.

A licensed plumber cannot certify work completed by an unregistered person, as that work is considered illegal plumbing work. However, as a licensed plumber, you may take over the job by re-doing the work and taking responsibility through certifying the work.

Plumbers may report any alleged illegal plumbing work to the VBA through VBA360.

It is not unlawful for anyone, including hardware and plumbing supply stores, to give advice on plumbing work. Therefore, the VBA has no legislative basis to stop this from occurring. The VBA can only take action where a law has been breached.

That said, it is illegal for unregistered or unlicensed persons to carry out regulated plumbing work.

Plumbers may report any alleged illegal plumbing work to the VBA through VBA360.

The new gutter installation must comply with the requirements of both of the following:

  • Plumbing Regulations 2018, which prescribe SA HB 39 Installation Code for metal roof and wall cladding and SAA HB 114 Guidelines for the design of eaves and box gutters as deemed-to-satisfy requirements
  • Plumbing Code of Australia (PCA) 2019, which requires AS/NZS 3500.3 Plumbing and drainage Part 3: Stormwater drainage as a deemed-to-satisfy requirement.

If it is not possible to install according to the deemed-to-satisfy requirements, plumbers may also use a performance solution approach to meet the PCA requirements.

Under Regulation 21 of the Gas Safety (Gas Installation) Regulations 2018, a plumber carrying out gasfitting work must take the following steps without delay when they become aware of a danger arising from a defect in a gas installation:

  • take all steps necessary to make the gas installation safe
  • notify the owner of the gas installation and the occupier of the premises in which the installation is situated of the defect.

If a plumber is unable to take the necessary steps to make the gas installation safe (e.g. repairing or isolating the appliance with the owner’s consent), they must notify Energy Safe Victoria without delay.

The new excessive noise requirements in the PCA apply to new and existing buildings, which would apply to alterations and renovations.

Plumbers should ensure the neighbours’ separating wall, floor or ceiling is appropriately sound-rated if installing pipework in the separating wall, floor or ceiling.

The 45-degree delivery temperature for heated water is required in the following buildings:

  • the residential part of an aged-care building
  • the patient care area of a healthcare building
  • any part of an early childhood centre or primary or secondary school used by children
  • a designated accessible facility in a common area (e.g. pools and garden areas) of a Class 2 building
  • a designated accessible facility in any Class 3, 5, 6, 7, 8, 9a, 9b, 9c or 10 building.

A 'public disabled bathroom' in a football club would be required to meet the 45-degree delivery temperature requirements.

Original question in full:

With the performance solutions, if it’s been designed a certain way and I go to look at a job say 2 years after it’s finished and the house has been sold, say the third person in the house has no idea how it was designed. Are they supposed to have copies of these certificates so I know… because I look at them and go ‘that doesn’t comply’ but it could comply if all this had been done? So, if I get a copy of the certificate, should it be all on there?


Plumbing installations using the performance solution approach must identify this on the relevant Compliance Certificate. Doing so ensures the work can be readily identified as having used a non-deemed-to-satisfy approach. VBA360 has a feature allowing licensed plumbing practitioners to attach all relevant documentation associated with an installation (including performance solutions) against the relevant Compliance Certificate. The owner of a property may also apply to the VBA to obtain copies of relevant Compliance Certificates issued for plumbing work completed on their property by making a freedom of information application at

The owner of a property may apply to the VBA to obtain copies of relevant Compliance Certificates issued for plumbing work completed on their property by making a freedom of information application at

Any plumbing work carried out by a responsible plumber on an existing plumbing system is required to meet the relevant performance requirements contained in the Plumbing Regulations 2018 and/or the Plumbing Code of Australia 2019. If the proposed installation uses a performance solution approach, you will need to ensure the relevant performance requirements of the PCA are met, where applicable. For plumbing work not covered by the PCA, the relevant requirements of the Plumbing Regulations 2018 apply. For an existing plumbing installation using the deemed-to-satisfy approach, the work will need to meet the current standard.

In relation to risk metrics for assessing the likelihood of a system failing to perform under a performance solution, the VBA is not aware that any such metric is currently available. The VBA expects the responsible plumbing practitioner to make their own enquiries and do their own research to determine the likelihood of system failure, which may be verified by expert advice in the relevant field.

The VBA and Energy Safe Victoria have developed guidance videos to assist gasfitters with the testing process.

  • Visit the ESV website for a video on how to conduct a negative pressure test and assess its results.
  • Visit the VBA website for a video covering competency modules on how to conduct carbon monoxide spillage tests.

The VBA has also published information covering testing for negative pressure and carbon monoxide, and what to do if you detect spillage.

Note: For new gas installations, refer to AS/NZS 5601.1 Appendix R. For existing gas appliances, refer to AS/NZS 5601.1 Appendix R or ESV Gas Technical Information Sheet 38.

Energy Safe Victoria resources:

In the event that negative pressure has been detected and the owner does not agree to the installation of permanent ventilation, contact the VBA via

In the event that carbon monoxide spillage has been detected and the owner does not agree to isolate/disconnect the gas heating appliance, contact ESV.

If you haven't completed the carbon monoxide (CO) module, you will be required to complete it as part of your licence exam, unless you have completed your apprenticeship in the last three years. In this case, Registered Training Organisations are required to cover knowledge of CO safety and spillage testing when delivering and assessing gasfitting installation competency units. Examination requirements are constantly being reviewed. During an examination, a participant could be expected to demonstrate knowledge of any aspect of gasfitting.

Carbon monoxide (CO) testing is required knowledge for gasfitting competency units. If you believe this content is not being covered, please contact the TAFE and/or Australian Skills Quality Authority (ASQA) at

Gasfitting allows the registered and/or licensed plumber to install, test and commission a gas appliance. Type A Appliance servicing work allows the registered and/or licensed plumber to carry out cleaning, maintenance and repair of Type A gas appliances.

Refer to the Plumbing registration and licences section for more information.

If you have successfully completed the Combustion Spillage Learning Module, along with the VBA's Carbon Monoxide Safety Program, you will not need to complete another update in order to maintain your licence.

The requirements for licensing in Type A Appliance Conversion are listed in the plumbing registration and licences section.

This is no longer the case. VBA360 now times out after 20 minutes. The message warning about the six-minute timeout will be updated shortly.

Under Victorian plumbing laws, only registered or licensed plumbing practitioners can carry out plumbing work in the class(es) of their qualifications. Apprentices who are indentured to a registered or licensed plumber, and who are supervised, are also able to undertake plumbing work. Labourers without the relevant qualifications cannot carry out plumbing work. Definitions of plumbing work can be found in the Plumbing Regulations 2018 or the plumbing registration and licences section.

For Deemed-to-Satisfy compliance, refer to AS/NZS 3500.3 section 3 for design and calculation requirements (e.g. roof catchment area, ARI, cross-section of gutters etc.) and AS/NZS 3500.3 section 4 for installation requirements.

You can also refer to the VBA’s Technical Solution Sheet 4.04 (PDF, 933.99 KB).

Plumbing practitioners are only responsible for the work they carry out. If the proposed plumbing work is connected to a non-compliant plumbing system (thereby impacting on the performance of the proposed system), the VBA recommends the non-compliant system be brought up to standard. The owner should be notified of the existing non-compliant work (and provided with options for reaching compliance where possible). The plumber should identify what work they carried out on their compliance certificate.

It is an offence to perform or certify work that does not comply with plumbing laws.

Clause 4.9.1 (b) of AS/NZS 3500.2 allows for the entry level of the branch drain to be on grade where the junction is used to make the connection to the main drain of the same size.

No – AS/NZS 3500.2 Clause 4.9.2 states: "Junctions installed in the vertical plane for the connection of a single discharge pipe or a drain, shall have an upstream angle not greater than 45°". Therefore, sweep or 88-degree junctions on their back would be deemed non-compliant if installed in these scenarios.

AS/NZS 3500.4 Clause 1.11.2 (a) specifies that heated water must be delivered at a maximum of 45°C at the outlet of sanitary fixtures used primarily for personal hygiene purposes for the aged, the sick, children or people with disabilities in healthcare and aged care buildings, early childhood centres, primary and secondary schools, and nursing homes or similar facilities.

The scope of building to which this temperature limitation applies has also been broadened to include designated accessible facilities in any part of a Class 3, 5, 6, 7, 8, 9a, 9b or 10 building, as defined in the Plumbing Code of Australia. This means that water temperature must not be more than 45°C in any designated accessible facility in any building, except private homes or apartments.

Note: a 42°C temperature limitation may be associated with the risk management plan of a particular site, such as a hospital or aged care facility. Contact the appropriate facilities management staff for specifications on their risk management plan process.

Thermostatic Mixing Valve work is a specialised class and applicants must hold Water Supply work to be eligible for registration or licensing in this new class. The new specialised class is subject to a delayed twelve-month implementation and will commence on 18 November 2019.

Water supply plumbers will have 12 months from the start of the new Regulations to apply to the VBA and demonstrate that they hold the necessary level of competence if they wish to keep doing thermostatic mixing valve work after that date.

Property owners, consumers or plumbers can lodge a complaint about non-compliant plumbing work with the VBA via the VBA360 portal.

If the work is of a commercial or industrial nature, contact Energy Safe Victoria.

Yes – you can download the Plumbing Regulations 2018 from the Victorian Legislation and Parliamentary Documents website.

Energy Safe Victoria has published an updated list of defective open-flued gas heaters.

Contact the gas appliance manufacturer to check whether any rectification works have been performed on a defective gas heater.