What standard applies to bathroom waterproofing in Australia?

AS 3740 sets out the requirements for waterproofing domestic wet areas. AS 4654 covers membranes for external above-ground use. Both standards specify substrate preparation, membrane selection, coverage height, and detailing at junctions, drains and penetrations.

How long does bathroom waterproofing last?

A correctly installed bathroom membrane should last the life of the tiles and substrate — 15 to 20 years or more. Most premature failures come from poor substrate preparation, incomplete coverage, or inadequate detailing at junctions and drains.

Do I need to waterproof a bathroom renovation?

Yes. If you're renovating a bathroom, the existing waterproofing should be assessed and typically replaced. Waterproofing over a degraded or water-damaged substrate will fail. We assess the substrate before specifying the new membrane system.

Service

Bathroom and wet area waterproofing to Australian Standards.

Name: Driftform
Address: Byron Bay, NSW, AU
Telephone: 0431 522 689

New bathroom and wet-area waterproofing for residential and selected commercial work, installed to AS 3740 and AS 4654. The membrane is behind the tiles — and the part that costs the most when it fails.

Blue waterproofing membrane applied by brush to a shower recess corner and niche, installed to AS 3740

A bathroom membrane fails behind the tiles. By the time you see it on the ceiling below, the substrate is usually wet, the damage is done, and the repair costs far more than doing it right the first time.

Most leaking bathrooms we see weren't installed wrong in one big way. They were installed wrong in a dozen small ways — a corner that wasn't reinforced, a floor waste that wasn't bonded, a membrane that didn't turn up the wall high enough, a junction between sheet and liquid membrane that wasn't detailed. AS 3740 sets out the requirements for waterproofing domestic wet areas, and AS 4654 covers membranes for external above-ground use. We install to these standards — correct substrate preparation, the right membrane system for the substrate and tile, full coverage to the required height, and correct detailing at every junction, drain and penetration.

We take on new bathroom and wet-area waterproofing for residential renovations and selected commercial work — laundries, kitchens, and common-area wet rooms in strata and commercial buildings. Not the flagship service, but work we do properly, using specified systems from our product partners.

On site

Completed membrane — floor, walls, and penetrations detailed.

Membrane applied to the floor and lower walls — floor wastes bonded, plumbing penetrations sealed, coverage to the required height.

Bathroom waterproofing — bright blue membrane applied to floor and lower walls, with floor wastes and plumbing penetrations detailed — Membrane applied to the floor and lower walls — floor wastes bonded, plumbing penetrations sealed, coverage to the required height.

Membrane continued up the shower alcove to the window — the Geberit in-wall cistern frame detailed in behind.

Same bathroom showing blue membrane continued up the rear wall of the shower alcove to the window, with a Geberit cistern module set in — Membrane continued up the shower alcove to the window — the Geberit in-wall cistern frame detailed in behind.

Wet areas we cover

New bathrooms

Full membrane systems for new residential and commercial bathrooms, installed to AS 3740.

Shower recesses

Correct waterproofing to shower floors and walls, including step-down and barrier-free showers.

Laundries and wet rooms

Waterproofing for laundries, utility rooms and other wet areas in residential and commercial buildings.

Balcony wet areas

Waterproofing for balconies and decks above habitable space, with correct fall and drainage detailing.

Common-area wet rooms

Strata and commercial common-area wet rooms, plant rooms and cleaning areas.

Renovation work

Strip-back and re-waterproofing of existing wet areas during renovation, with correct substrate assessment.

Installed to AS 3740 and AS 4654.

Every new wet area is installed to the relevant Australian Standard, using specified membrane systems. The membrane choice depends on the substrate, the tile, the expected movement, and the exposure — made on the specifics of your job, not a default.

If you're renovating and the existing substrate is water-damaged, we'll tell you before we membrane over it. Waterproofing over a degraded substrate is a waste of your money and our reputation.

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Tell us about the project.

Send a few details and we'll come back within one business day. Active leaks — call us directly.

Send details 0431 522 689