Bathroom waterproofing done to AS 3740.
The number-one cause of bathroom failure in Geelong’s older homes. We strip back to substrate, install a compliant membrane, cure it, and certify it before a single tile goes back on. Licensed waterproofer, fully certified.
The leak you can’t see — until it’s expensive.
Why Geelong’s older bathrooms leak
Newtown’s Victorian and Edwardian homes and the post-war stock of Belmont, Highton and Lara almost all carry their original wet-area membranes — many predate modern standards, and plenty were never compliant in the first place. Decades of thermal movement crack them; coastal humidity off Corio Bay and Bass Strait keeps the structure damp and feeds mould. Water tracks into wall framing and subfloors for years before anyone sees a stain.
1. Investigate & strip back
We remove the affected tiles and the old membrane back to a sound substrate, and inspect the framing and subfloor for rot. There is no shortcut here — you cannot reliably waterproof over an unknown old membrane, and patching only delays the next failure.
2. Prepare the substrate
The membrane is only as good as what it sticks to. We make good the substrate, set the correct falls to the floor waste so water actually drains, prime, and treat junctions, penetrations and the shower hob/base — the points where membranes fail first.
3. Install to AS 3740:2021
A licensed waterproofer installs the membrane to AS 3740:2021 (Waterproofing of domestic wet areas) — correct coverage, the right number of coats, bond breakers at movement joints, and turn-ups to the required heights at the shower and walls.
4. Cure, certify, then tile
The membrane cures 24–48 hours and is certified compliant before tiling. Only then do we re-tile, with proper falls, suitable adhesive and mould-resistant grout and silicone. The certificate is your proof at resale or for an insurance claim.
Realistic pricing (2026)
- Waterproofing rate (standalone): $40–$100 per m², most bathrooms $60–$80/m²
- Typical Geelong bathroom membrane work: approx $700–$1,500
- Re-waterproof a leaking bathroom (tile removal + re-tile): priced after inspection — tiling is the larger cost
Why we never just re-tile over a bad membrane
It’s the fastest way to make a bathroom look fixed — and the surest way to be back in 18 months tearing out brand-new tiles to chase a leak that never went away. Re-tiling over a failed or unknown membrane is the corner we will not cut, because it always costs the homeowner more in the end. Strip, re-membrane, certify, re-tile — once, properly.
Licensed, compliant, certified.
In Victoria wet-area waterproofing must be done by a licensed waterproofer and certified to AS 3740 — you cannot legally do it yourself even on an owner-builder permit. We provide the compliance certificate on completion, and where the broader work exceeds $16,000 it’s carried out under VBA registration with domestic building insurance. That paperwork is exactly what a building inspector looks for at sale.
Other bathroom services.
Full bathroom renovation
Strip-out to fit-off, fixed price.
Details →Ensuite & small bathroom
Space-smart ensuites and powder rooms.
Details →Accessible & walk-in
Step-free showers, grab rails.
Details →Laundry renovation
Joinery, benchtops, layouts.
Details →Got a leaking bathroom in a particular suburb? See Newtown and Belmont — or book a free inspection now.
Free waterproofing inspection & quote.
We’ll find the leak source and quote a fixed price within 48 hours.