Bathroom Waterproofing Perth

Yes. Under the Building Code of Australia (NCC) and AS 3740-2021, all wet areas in bathrooms must be waterproofed by a licensed contractor. In Western Australia, the WA Building Commission oversees compliance, and waterproofing work must be inspected before tiling can proceed.

Most bathroom waterproofing jobs in Perth take 2–3 days. This includes surface preparation (day 1), membrane application with drying time between coats (day 1–2), and inspection before tiling (day 2–3). Perth's warm, dry climate often helps membranes cure faster than in more humid regions.

Under AS 3740-2021, the entire shower floor and walls to a minimum 1800mm height must be waterproofed. The bathroom floor requires waterproofing extending 150mm up all walls. Areas around baths need waterproofing to 150mm above the rim. Floor waste areas and any junctions between walls and floors must be sealed with appropriate detailing.

In some cases, yes. A licensed waterproofing contractor can apply certain liquid membranes over existing tiles after proper preparation, including cleaning, priming, and sealing grout lines. However, this is only suitable if the existing tiles are well-bonded and the substrate is structurally sound. A full inspection is recommended first.

All waterproofing contractors in Perth must be registered under the WA Building Services (Registration) Act 2011. You can verify a contractor's licence through the WA Building Commission. Our service connects you with up to 3 pre-vetted, licensed professionals who specialise in bathroom waterproofing across the Perth metro area.