The Plumbing and Drainage Regulation 2017 has been amended to streamline the process for sanitary drainage works.

Under the amendments, which took effect on 17 April 2026: 

• a sanitary drainage system must be installed in accordance with the design

• there is an exemption to Plumbing Code of Australia compliance C2P7(1) if it follows deemed-to-satisfy provisions

• there is a new deemed-to-satisfy provision requiring flexible joints to be used in a drain in ground that is filled or unstable, water-charged, soil class H1, H2 or E, and in the opinion of a recognised expert, is likely to move and damage the drain and surrounding structures

• a recognised expert, meeting certain qualification requirements, must prepare designs for a sanitary drainage system

• the design must be supplied to the plumbing regulator or delegate with a notice of work

How does this affect your work?

The amended regulation allows you to submit sanitary drainage system designs and start work without delay.

You no longer need to: 

• prepare and submit a performance solution for flexible joints including suitability statements and owners’ signatures
• wait for associated Building Commission NSW review and acknowledgement.

A recognised expert must now prepare sanitary drainage system designs with flexible joints in certain ground conditions (filled or unstable, water-charged, soil class H1, H2 or E) where the recognised expert has the opinion the drain is likely to move and damage the drain or surrounding structures.

You can send sanitary drainage system designs directly to the local plumbing regulator undertaking inspections at the time of submitting a notice of work.

Sanitary drainage systems with flexible joints need to be installed as designed.

More information

For more information, refer to the below: 

For further information email PCA@customerservice.nsw.gov.au