Tiling vs waterproofing licences in Australia: per-state rules

What it is

Tiling and waterproofing are two of the most defect-heavy trades in residential construction. State regulators have responded by carving them out as separately licensed trades in NSW and Queensland, bundling them inside a single domestic builder class in Victoria, and folding them into broader contractor licensing in WA and SA.

The split matters because tiling defects and waterproofing defects flow into different insurance lines, attract different statutory warranty terms and trigger different audit pathways. A tiled shower that fails because the screed cracked is a tiling defect. The same shower failing because the membrane was not lapped to the waste is a waterproofing defect. State licensing regimes try to keep these accountable by trade.

Tiling and waterproofing licences by state

NSW

NSW Fair Trading issues two separate trade licences under the Home Building Act 1989. Wall and Floor Tiling is its own contractor licence covering ceramic, glass, marble, slate, stone and terracotta tiles fixed to floors, walls, hearths, fireplaces, spas and pools. Waterproofing is a separately licensed trade for internal wet area waterproofing. Both licences are required for residential building or trade work valued over $5,000 in labour and materials including GST. NSW Fair Trading guidance is explicit that a tiler who is not also licensed in waterproofing cannot apply the waterproof membrane in a wet area.

To get a NSW Waterproofing licence the applicant needs Certificate III in Wall and Floor Tiling or Construction Waterproofing as relevant, plus at least two years of verified experience.

Queensland

QBCC issues a Wall and Floor Tiling licence and a separate Waterproofing licence. The Wall and Floor Tiling scope covers cutting and fixing tiles to fireplaces, floors, hearths, spas, swimming pools and walls. The Waterproofing scope covers applying, installing and repairing waterproofing systems, including surface preparation, for the prevention of moisture penetration. A tiler cannot waterproof unless they hold a waterproofing licence, but a waterproofer can prepare surfaces for tiling without a tiling licence. The QBCC licensing threshold for building work is $3,300.

Victoria

Victoria bundles the two trades into one registration class. The Domestic Builder Limited (Floor and Wall Tiling) class registered through the Building and Plumbing Commission covers tiling for homes and Class 10 structures and explicitly includes waterproofing of the tiling. The applicant must demonstrate capacity to apply waterproofing for internal wet areas as appropriate to the floor and wall tiling installation. A separate Domestic Builder Limited (Waterproofing) class exists for waterproofing as a standalone trade outside of tiling.

Western Australia

WA does not issue dedicated tiling or waterproofing trade licences. A tiler or waterproofer who contracts for building work over $20,000 must register as a Building Services Contractor through DMIRS in an appropriate class. Below that threshold and as an employee of a registered builder no individual registration is required. The building practitioner who is named on the building permit carries responsibility for the wet area waterproofing under the Building Act 2011 (WA), regardless of which subcontractor applied the membrane.

South Australia

SA folds both trades into the Building Work Contractor framework administered by CBS. A contractor who undertakes tiling or waterproofing work above $12,000 needs a contractor licence and the applicant must hold the relevant Certificate III qualification.

Why the split matters for compliance

Wet area waterproofing has its own compliance overlay separate from the licence question. The NCC adopts AS 3740 for waterproofing of domestic wet areas and the state plumbing or building regulator typically picks up that standard by reference. A tiler who is also licensed in waterproofing must still apply a system that complies with AS 3740 and any state variation.

The licensing question intersects with the compliance question at the warranty stage. Statutory warranty insurance in NSW, QLD and VIC will respond to a defective waterproofing claim only if the work was carried out by a person licensed or registered to do that work at the time. Unlicensed waterproofing voids the warranty cover even where the membrane was technically installed to AS 3740.

Penalties for unlicensed tiling or waterproofing

In NSW the maximum penalty under the Home Building Act 1989 for doing residential trade work without the relevant licence is $22,000 for an individual and $110,000 for a corporation. In Queensland the QBCC issues infringement notices and prosecutes unlicensed contractors, with maximum penalties that escalate for repeat offences. In Victoria the BPC can refuse, suspend or cancel registration and issue infringement notices under the Building Act 1993.

TradeLens triggers

A TradeLens audit on a residential job flags tiling and waterproofing risk when:

• The tiling subcontractor's licence on record does not include a waterproofing endorsement and the scope of work includes a wet area in NSW or QLD.
• The signed waterproofing certificate names a person whose licence has lapsed or whose qualification does not cover the system installed.
• The job is in Victoria, the work is over $10,000 and the registered domestic builder did not engage a registered tiling and waterproofing limited builder for the wet areas.
• A WA job over $20,000 has no registered Building Services Contractor named as responsible for wet area waterproofing on the building permit.

Catching the gap before tiles go down costs a licence lookup. Catching it after means stripping the bathroom and reinstating it under a properly licensed practitioner because the warranty insurer will not respond to defects on unlicensed wet area work.