Bathroom waterproofing done right the first time
Water passes through tile joints constantly. It is the membrane underneath that keeps it out of your framing and floor. We install certified Ardex systems for Auckland bathrooms, new builds and renovations, with a PS3 producer statement on completion.
What bathroom waterproofing actually is
Bathroom waterproofing is a membrane applied to the floors, walls and shower area before tiling. The tiles and grout are the wear surface; the membrane is the barrier. Get the membrane wrong and everything above it is decoration on a slow leak.
In New Zealand this is not optional. Building Code clause E3 (internal moisture) requires every wet area to be waterproofed, membranes must meet AS/NZS 4858, and consented work needs a PS3 producer statement from a qualified applicator before Auckland Council will sign it off. We are PS3 registered authors with Auckland Council, so the paperwork comes with the job.
How we waterproof a bathroom
Corners are where most leaks start, so that is where we spend the time. Every bathroom gets:
- Substrate assessment before anything is applied, so problems are found early, not tiled over
- Full membrane coverage of the shower floor and walls
- Sealed floor-to-wall junctions and reinforced internal and external corners
- Proper detailing around pipes, drains and penetrations
- Correct membrane thickness, checked, with full curing before tiling starts
We install Ardex-led membrane systems as a complete system: membrane, primer, bond breakers and sealants matched by the manufacturer, not mixed products. A correctly installed membrane is designed to outlast your tiles.
What failed waterproofing looks like
Most failures stay invisible until the damage is done. Lifting or drummy tiles, a musty smell that will not clear, black mould at the skirting, soft flooring outside the shower. By that point water has been in the framing for months, and the honest fix is a full strip-out and rebuild of the bathroom, new substrate, new membrane, new tiles.
We see the aftermath often, and the cause is nearly always the same: wrong products, thin application, or no certification. If your bathroom has already failed, we rebuild it properly as a renovation, waterproofing and tiling handled by one crew, one system, no finger-pointing between trades.
Before you book
Do I need a PS3 for bathroom waterproofing in Auckland?
If the work needs building consent, yes. The PS3 producer statement confirms a qualified applicator installed the membrane to code, and Auckland Council inspectors ask for it before issuing the Code Compliance Certificate. We supply it on completion.
How much does bathroom waterproofing cost?
It depends on the size of the bathroom, the substrate condition and how much detailing the layout needs. We visit the site, then give you a clear, itemised quote so you can see exactly what you are paying for before work starts.
Can I waterproof my bathroom myself?
For consented work, no, a qualified applicator is required. Beyond that, DIY membranes are where most of the failures we rebuild come from. If the membrane fails, the fix is stripping the bathroom back to the substrate, so this is not the place to save money.
How long does waterproofing take before tiling can start?
Typically one to two days of application, plus curing time before tiling can start. Tiling only starts once the membrane has fully cured. Rushing this step is one of the most common causes of failure, so we do not.
Do you do both the waterproofing and the tiling?
Yes, and that is the point. One contractor owns the whole wet area, the membrane and the tiles are installed as one compatible system, and there is no gap in responsibility between trades.
Get your bathroom waterproofed properly
Free site visit anywhere in Auckland, then a clear, itemised quote. Call 021 818 013 or send us the details.