Which rooms in a Perth home count as wet areas?

Bathrooms, laundries and toilets are the main wet areas in a Perth home. Any room with a tap, floor waste or fixture that can spill water onto the floor can be treated the same way. AS 3740 sets the zones, so list every fixture when you describe the room.

Does swapping a laundry tub or vanity mean redoing the membrane?

Not always. If the tiles and floor stay put and nothing is cut into, the existing membrane usually stays. If removing the old unit lifts tiles, cracks sheeting or opens the floor, that section should be made good before the new unit and finishes go on. Painting alone does not touch the membrane.

Which parts of a laundry or toilet need membrane?

The floor is the main zone, especially around the floor waste and the toilet pan. In a laundry, the wall behind and beside the tub and washing machine also needs attention. Exact zones depend on the layout under AS 3740, so a contractor confirms them on site.

Do new Perth homes need laundry and toilet waterproofing?

Yes. New homes in Perth are built to NCC 2022, which points to AS 3740 for wet areas, so laundries and toilets get a membrane during construction. If you later find damp or lifting tiles in a newer home, have the wet area checked before any finishes are replaced.

What wet area waterproofing rules apply in Western Australia?

Western Australia follows the National Construction Code, and NCC 2022 relies on AS 3740 for waterproofing wet areas in homes. That covers bathrooms, laundries and toilets alike. Licensed and insured contractors work to these rules and can explain which zones apply to the room you are renovating.

Laundry and Wet Area Waterproofing in Perth, WA

Who laundry and toilet waterproofing in Perth suits

If you are renovating a laundry, toilet or other wet room in Perth, it most likely needs a membrane wherever water can reach the floor or walls. AS 3740 sets how wet areas in homes are waterproofed, and it reaches well beyond the shower. Which zones apply depends on the fixtures in the room and the work you plan.

Which laundry, toilet and wet room zones count

In a laundry, the floor and the wall behind and beside the tub or washing machine are the usual concern. In a toilet, it is the floor, particularly around the pan and any floor waste. A powder room or downstairs WC with a tap or floor drain can fall under the same rules, so name every fixture in the room.

When minor works trigger a new membrane

Swapping a vanity, laundry tub or toilet suite can disturb the membrane where it meets the floor or wall, and lifting floor tiles almost always exposes it. Once the substrate is open, new finishes should go back over a sound membrane. Painting walls or changing tapware on its own usually leaves the membrane untouched.

Why the vanity or paint decision is not over-scoping

Many owners worry that one new vanity will turn into a full strip-out. The decision turns on whether tiles, sheeting or the floor are being disturbed, not on the size of the job. Someone who sees the room can confirm whether the existing membrane stays or a section needs redoing before finishes go on.

Australian Standards and the NCC in a WA home

NCC 2022 points to AS 3740 for waterproofing wet areas in houses, and Western Australian homes are covered just as homes elsewhere are. New builds are done to it, and renovations that replace wet area finishes are expected to meet it as well. The parts that apply depend on your room layout.

Next step for your laundry or wet room

Before you book any finishes, list the room, every fixture with water to it, and whether tiles or the floor will be lifted. A photo of the floor waste and the wall behind the tub or pan helps. Add the suburb, and the zones needing membrane can be sorted out before anything is tiled or painted.

Laundry and Wet Area Waterproofing Services We Offer

✓Laundry Waterproofing

Floor and wall zones around the tub, washing machine and any floor waste in a renovated laundry.

✓Toilet and Powder Room Waterproofing

Floor membrane around the pan and floor waste, sealed where the floor meets the walls.

✓Membrane Repair After Minor Works

Making good a section of membrane disturbed when a vanity, tub or toilet suite is replaced.

How it works

1
Describe the room and works
Note the room, each fixture with water to it, whether tiles or flooring will come up, and your suburb.
2
Confirm the wet area zones
The contractor checks which floor and wall zones count as wet areas under AS 3740 for that room and fixture layout.
3
Prepare and apply the membrane
The substrate is prepared and the membrane goes on over the agreed zones, including the junctions at the floor waste and walls.
4
Cure, then finish
The membrane is left to cure before tiles, a vanity or paint go back, so the finishes sit over a sound layer.