| Form 4 | Form 16 | |
|---|---|---|
| What it covers | Notifiable plumbing and drainage work | An aspect of building work, e.g. waterproofing |
| Legislation | Plumbing and Drainage Act 2018 | Building Act 1975 |
| Who issues it | The licensed plumber who did the work | The competent licensed person for that aspect |
| Who receives it | Lodged with the QBCC | Given to the building certifier |
| Typical trigger | Fixture relocations, new plumbing | Bathroom waterproofing, structural aspects |
What exactly is a QBCC Form 4?
A Form 4 is the certificate a licensed plumber lodges with the QBCC to certify that notifiable plumbing work complies with the Plumbing and Drainage Act 2018 and AS/NZS 3500. Queensland splits plumbing work into categories: permit work, notifiable work, minor work and unregulated work. Notifiable work sits in the middle, jobs significant enough to need certification but not a council permit, such as relocating fixtures in a bathroom renovation, replacing a hot water system in a new position, or extending water and sanitary pipework in an existing home. The plumber who does the work lodges the Form 4 after completion, and you as the owner can request a copy. Keep it, because it is your proof the work was done legally.
What is a Form 16 and who signs it?
A Form 16 is an inspection certificate under the Building Act 1975 that certifies a specific aspect of building work, and it is signed by the competent person responsible for that aspect. The building certifier overseeing your renovation or new build cannot personally inspect every element, so the law lets them rely on Form 16 certificates from licensed people for particular aspects. The everyday example is waterproofing: the licensed waterproofer who applies the shower membrane issues a Form 16 for that aspect, and the certifier relies on it when approving the building work. Form 16s can also cover other aspects such as structural elements, always signed by whoever is competent and licensed for that piece.
Why does a bathroom renovation involve both forms?
Because a bathroom renovation is plumbing work and building work at the same time, so each stream is certified separately. Move the toilet or shower and the plumbing side is notifiable work that ends in a Form 4 from the licensed plumber. Retile the shower and the waterproofing is building work that ends in a Form 16 from the licensed waterproofer to the certifier. Neither form substitutes for the other. In our experience the paperwork gap usually appears when a renovation was run by an unlicensed operator or an owner-builder who did not realise two separate certification chains applied. Both documents matter at sale time, when buyers' solicitors and building inspectors ask for them.
What if plumbing work was done without a Form 4?
Uncertified notifiable work can usually be fixed with retrospective certification, which typically costs $400 to $1,500. We inspect the work, test it, correct anything that does not meet AS/NZS 3500, and lodge the certification so the record is clean. Where it sits in that range depends on how much of the work is accessible and how much needs correcting. We see this most often when people are selling and a building and pest report flags unapproved plumbing, or when a past renovation was done cheap and undocumented. Sorting it before you list is far less painful than negotiating it off your sale price.
How do I check or get copies of these forms?
For Form 4s, ask the plumber who did the work or contact the QBCC; for Form 16s, ask the building certifier who handled the project. The QBCC also runs a public licence check where you can confirm any plumber or contractor holds the licence they claim, which we recommend doing before any notifiable work starts. If you have lost paperwork from an old renovation, the certifier's file and council records are the places to look. And if the paperwork never existed, that is the retrospective certification conversation above, better had now than during a contract crunch.
Sources: Queensland Building and Construction Commission (qbcc.qld.gov.au), Plumbing and Drainage Act 2018 (Qld), Building Act 1975 (Qld).
Renovating a bathroom or missing certification?
We do the plumbing side of bathroom renovations properly, Form 4 lodged, and we certify uncertified past work. Call Jieye on 0472 657 042, read our Form 4 guide or see our bathroom renovations service page.