Who provides waterproofing compliance certificates in NSW? (Bathroom | Building & Approvals)

If you’re planning a bathroom renovation in Sydney—whether you live in a Bondi apartment, a Ryde townhouse, or a big family home in the Hills—there’s one thing you’ll hear again and again: waterproofing certificate. And rightfully so! Waterproofing is the invisible hero of every successful bathroom upgrade. Nobody shows guests the waterproofing layer and says, “Look at that membrane, isn’t she gorgeous?” But trust me—when waterproofing is done wrong… oh boy. That’s when tears, mould, leaks, swollen skirtings and not-so-happy strata managers come out to play.

So, who actually provides waterproofing compliance certificates in NSW? And how does the whole thing really work in Sydney’s bathroom renovation world? Let’s break it down in a simple, practical and slightly humorous way so anyone—no matter how much construction knowledge they have—can understand it.

1. The Short Answer: Licensed Waterproofers Provide Waterproofing Compliance Certificates in NSW

The certificate is issued by the person who physically carried out the waterproofing work.
Not the builder.
Not the tiler.
Not the plumber.
Not the certifier.
And definitely not your next-door neighbour who once watched a YouTube video.

It must be issued by a licensed waterproofer, holding one of the following licences from NSW Fair Trading:

• Waterproofing Licence (Contractor)

• Bathroom, Kitchen & Laundry Renovator Licence with the waterproofing category

• Company licence (if the company, not an individual, is contracted to waterproof)

This certificate is not just a “nice-to-have.” It’s an essential compliance document for:

• warranty purposes

• strata approval records

• future property sales

• insurance claims

• council-related inspections (in some cases)

• proving your renovation meets NSW building standards

In short: this document is a big deal in Sydney.

2. What Is a Waterproofing Certificate, Really?

Think of it like the waterproofing world’s birth certificate.
It confirms:

• who did the waterproofing

• their licence number

• the products and systems used

• that the installation meets AS 3740 – Waterproofing of Domestic Wet Areas

• the exact area waterproofed

• the date of installation

This piece of paper becomes pure gold if something ever goes wrong. Without it, you’re basically trying to claim warranty on a TV you bought from a guy in a carpark. Not a good position to be in.

3. What Waterproofing Works Must Be Certified?

In NSW, any waterproofing carried out in a residential bathroom must be done by a licensed professional—and certified.

This includes:

• shower recess waterproofing

• bathroom floors

• walls (to the required heights)

• niches

• laundry wet areas

• bath hob and surrounding walls

• any waterproofing behind tiles and fixtures

If the area gets wet or even slightly damp, waterproofing is almost guaranteed to be required.

4. Why the Certificate Matters So Much in Sydney

Sydney’s bathrooms face a special combination of challenges:

• constant humidity

• daily showers (sometimes 2–3 in big households!)

• small apartments with limited ventilation

• older plumbing systems in pre-war terrace homes

• strata schemes with strict compliance obligations

In strata buildings especially, one leak can cause:

• damage to common property

• insurance claims

• finger-pointing between owners

• an angry strata manager chasing you at 7am

Having a waterproofing certificate protects you. It proves your renovation followed the rules, and it makes life much smoother if strata, council, or an insurance assessor ever gets involved.

5. When Do You Receive the Waterproofing Certificate?

The certificate is normally issued after the waterproofing is completed and the final coat has dried—before tiling begins.

A typical timeline looks like this:

1. Bathroom demolition

2. Plumbing rough-in

3. Carpentry and sheeting

4. Waterproofing installation (multiple coats)

5. Drying/curing time

6. Waterproofing certification issued

7. Tiling begins

If anyone starts tiling over waterproofing without issuing the certificate, you’re heading into risky territory. That’s like leaving the house without your phone—feels wrong from the start, and it’s probably going to cause problems.

6. Can a Builder Provide the Certificate Instead?

No—unless the builder themselves holds the waterproofing licence and personally completes the waterproofing.

So if your bathroom renovator subcontracted the waterproofing work (which is extremely common), the subcontractor issues it.

Sydney experts usually work like this:

• waterproofing must be done by a licensed specialist

• certificate must come from the exact person/company that applied the waterproofing system

If someone tries to give you a certificate from a company or name you’ve never seen on-site… run. Fast.

7. What About Private Certifiers or Council Inspectors? Do They Issue It?

No.
Neither private certifiers nor council inspectors provide the waterproofing certificate.

Instead, they:

• request the certificate for compliance

• check that waterproofing meets standards

• inspect leakage-sensitive areas during renovation

• ensure the licensed person is actually licensed

So, think of it as:

• licensed waterproofer = does the waterproofing + issues the certificate

• builder/renovator = coordinates the work and keeps records

• certifier/council = oversees compliance and inspections

Everybody has a job. Nobody overlaps.

8. What Happens If Your Waterproofer Doesn’t Provide a Certificate?

That’s like going out for yum cha and not getting the bill—sounds fun for a moment but ends in tears.

If the certificate is missing:

• the job is considered non-compliant

• insurance may refuse coverage

• strata won’t accept the renovation

• warranties become extremely hard to claim

• council (if involved) may reject your final documentation

• selling the property later becomes complicated

A good renovator in Sydney will NEVER skip waterproofing certificates.
A great renovator will chase it before you even ask.

9. How Do You Check If Someone Is Properly Licensed to Provide the Certificate?

You can check licences for free using the NSW Fair Trading licence check tool.

You should verify:

• the person/company name

• licence categories (must include waterproofing)

• licence status (active, suspended, expired)

Always do this BEFORE waterproofing begins.
Sydney is full of “my cousin can waterproof cheaply!” stories that end with insurance nightmares.

10. Key Takeaways for Sydney Homeowners

Here’s the quick, no-nonsense summary:

• A licensed waterproofer provides the waterproofing compliance certificate.

• Builders, tilers, plumbers or certifiers cannot issue it, unless they hold the proper waterproofing licence.

• The certificate must be issued before tiling begins.

• It is required for warranties, strata, council compliance and insurance.

• Always check the licence to avoid future headaches.

Put simply: When the waterproofing is done, you want a certificate in your hand—like holding onto a golden ticket that keeps your bathroom safe, legal and protected for years.

Visit www.mb9.com.au to find out more information about kitchen, bathroom and house renovation services from MB9 Australia Pty Ltd.