Bathroom Waterproofing Requirements in NZ: What a PS3 Is and When You Need One
Water damage from a failed shower is one of the most expensive problems a New Zealand home can have — and it usually stays hidden until the floor is rotten. That's why the waterproofing under your tiles matters more than the tiles themselves. Here's a plain-English guide to the rules, the paperwork, and what to ask your tiler.
Why tiles alone aren't waterproof
Tiles and grout shed water, but they aren't watertight. Water gets through grout lines and hairline cracks over time. What actually protects your home is the waterproof membrane (also called tanking) applied to the walls and floor before tiling. If the membrane is missing, too thin, or poorly detailed at corners and drains, leaks are only a matter of time.
What the Building Code requires
Wet areas in NZ homes must meet Building Code clause E3 (Internal Moisture), which is about preventing water from damaging the building or creating unhealthy conditions. Durability is covered by clause B2. In practice this means a suitable membrane system, installed to the manufacturer's instructions, with correct falls to the drain and properly sealed junctions.
Do I need building consent for a tiled shower?
It depends on the job and on your council's view, so always check before you start:
Replacing linings, membrane and tiles in an existing bathroom may be exempt in some cases under Schedule 1 of the Building Act — for example, a 2024 MBIE determination found that installing a wet-area membrane when replacing existing linings in an existing house fell within the exemption for internal linings.
Creating a new tiled wet-area (level-entry) shower is treated by some councils, such as Auckland Council, as work that needs consent, because it involves carpentry and waterproof membranes.
Adding extra fixtures (for example a new ensuite) or changing the structure (recessing a concrete slab, altering framing) needs consent.
If you're in Wellington, Hutt City, Upper Hutt, Porirua or Kapiti, check with your local council or ask us — we deal with these requirements every week.
What is a PS3?
A PS3 producer statement – construction is a document the waterproofing contractor signs to confirm the membrane was installed according to the manufacturer's instructions and the approved plans. It records the membrane product used, the areas covered (such as the shower and bath surround), the applicator's details, and confirms the installer believes on reasonable grounds the work meets Building Code clauses B2 and E3.
When your job has a building consent, your council will usually ask for the PS3 before issuing the Code Compliance Certificate (CCC). Even when consent isn't needed, a PS3 is valuable proof of quality workmanship when you sell your home or make an insurance claim.
Questions to ask your tiler
Which membrane system will you use, and is it suitable for a shower floor?
Who applies the membrane — you, or a subcontractor?
How do you detail corners, drains and wall-floor junctions?
Will you provide a PS3 producer statement?
Does my job need building consent?
Certified waterproofing in Wellington
All About Tiles is a certified waterproofing applicator and provides PS3 producer statements for Wellington, Hutt City and Upper Hutt council compliance. Learn more about our PS3 waterproofing service or request a free on-site quote.
This article is general information, not legal advice. Consent requirements vary — confirm with your council before starting work.
