The Australian Building Codes Board keeps a free, public database of WaterMark certified products, and the part most builders miss is that it is a live register, not a printed list. Certificates are issued, renewed, varied, suspended and allowed to expire on it continuously. The tapware you priced in a January quote can be sitting on a different status by the time your plumber fits it in August, and nothing about the carton in the warehouse will tell you.

That matters because WaterMark is not a marketing badge. It is a mandatory certification scheme for plumbing and drainage products, administered by the ABCB, and the National Construction Code requires products used in plumbing work to be authorised for use. Volume Three of the NCC, the Plumbing Code of Australia, is the volume that carries it. Your state plumbing regulator enforces it, and your plumber signs their name to it when they issue a compliance certificate.

What the scheme actually covers

The WaterMark Schedule of Products is the list of what needs certification. Broadly it captures anything in contact with drinking water or carrying waste: taps, mixers, backflow prevention devices, pipe and fittings, cisterns, pans, traps, water heaters, grease arrestors. Products are certified against an Australian Standard or an ABCB Technical Specification, by a certification body accredited to do it, and the certificate names the licensee, the model, the standard and an expiry date.

Two things follow from that. A product is certified, not a brand. And a certificate is a snapshot with a use-by date on it, which is where the practical problem starts.

Why WaterMark certified products are a moving target

Certificates run for a fixed term and have to be renewed. A licensee can stop paying for one. A model gets superseded and the new revision sits under a different certificate. A certification body can suspend or withdraw a licence. None of that generates a phone call to you.

On a kitchen and bathroom package that is rarely a drama, because the fit-off happens weeks after ordering. On anything with a long runway it is a real risk. A dual occupancy where you priced the fixtures at tender, got planning eleven months later, then ordered, has had almost a year of register movement sitting under it. The same goes for a client who picked a specific mixer from a magazine in autumn and is still waiting on the frame in spring.

The other version of this is substitution. Your supplier is short on the specified trap, offers something that looks identical, and the store code changes on the invoice. If the replacement is not on the register, the person carrying that is your plumber and, through the contract, you.

The check takes two minutes

The register is searchable at the ABCB site and costs nothing. Search by product type, brand or certificate number and read three fields: the status, the expiry date and the standard it was certified against. If it is not there, it is not authorised, whatever the packaging says.

Worth building into the job at three points:

• At quoting. Check anything unusual before it goes on the fixture schedule. Imported tapware, specialty trade waste gear and anything a client found online are the usual offenders.
• At ordering. Re-check if more than a few months have passed since the quote. Note the certificate number on the purchase order so there is no argument later about which model was priced.
• At any substitution. Treat a supplier swap as a new product, not an equivalent. Get it in writing and check it.

We have gone through how to read a certificate line by line and what belongs in the client's handover folder in our guide to WaterMark certification and what the ABCB product database means for your quoting and your handover.

Where this lands in your admin, not your tools

Nothing above is hard. It is just paperwork that has to survive the gap between quoting and fitting, which is exactly the gap where site paperwork normally disappears into a ute console and a group chat.

The fix is boring and it works: the fixture schedule, the certificate numbers and the supplier confirmations live with the job, not in someone's inbox. When the client asks at handover what the shower mixer is, or the inspector asks for evidence of suitability, you open the job and it is there. That is the same argument behind keeping specs, variations and photos in one place rather than across three apps, which we covered in the 2026 guide to job management software for tradies.

It is also why code changes are a quoting problem before they are a building problem. When the NCC moves, the products, the standards and the evidence you need to keep all move with it, and the builders who feel it least are the ones whose job records are already in order. We wrote about that in more detail in our piece on National Construction Code reform and what it means for your next quote.

Check the register. Write the certificate number down. Keep it with the job.

If keeping that paperwork together is the part that keeps slipping, Built Simple is free to start. Download the app, put one job in it, and see whether the fixture schedule is easier to find in six months than it was this year.