Of everything that happens during a bathroom renovation, waterproofing is the one piece of work you’ll never actually see once the project is finished – and the one piece of work that matters more than any tile, tapware, or vanity you choose. Get it right, and it disappears completely behind the finishes, doing its job silently for decades. Get it wrong, and the consequences don’t show up immediately. They show up two, three, or five years later, as water damage in a ceiling below, a swollen skirting board, or a subfloor that’s been quietly rotting the entire time.
What the Standard Actually Requires
Waterproofing in Australian bathrooms is governed by AS3740, the Australian Standard for waterproofing of domestic wet areas. It sets out precisely where a waterproof membrane must be applied, to what height, and under what conditions – it isn’t a matter of professional opinion or a corner that can reasonably be cut to save time or cost. Reputable renovation companies build their process around this standard as a floor, not a ceiling, for what compliant waterproofing looks like.
Where Waterproofing Must Be Applied
The obvious zones are the shower recess and the floor generally, but AS3740 also requires waterproofing at every floor-to-wall junction in the room, around any floor waste, and up the walls within the shower to a specified minimum height – higher again for the walls that form the shower enclosure itself. Junctions and penetrations, where pipes or fixtures pass through the membrane, are disproportionately common failure points, which is exactly why they’re treated so specifically in the standard rather than left to general good practice.
Inspection and Testing: The Step That’s Easy to Skip
A membrane that’s been applied correctly still needs to be inspected and tested – typically flood-tested for a minimum period – before tiling begins and permanently conceals it. This is the last point at which a fault can be caught and rectified without demolishing finished work. Skipping or rushing this inspection is one of the more common shortcuts taken by less rigorous operators, precisely because a failure at this stage is invisible to the homeowner and won’t surface until well after handover.
Why Doing It Right the First Time Is Vastly Cheaper
The economics of waterproofing are stark and one-directional. Correct waterproofing, inspected and tested before tiling, adds a modest, predictable cost to a renovation budget. Remediating a failed membrane after the fact means removing tiles, potentially replacing a damaged subfloor or ceiling below, and repeating the entire waterproofing and tiling process – all while living with an unusable bathroom for considerably longer than the original renovation took. There is no version of this equation where cutting corners on waterproofing saves money in the long run.
Novalé’s Compliance Process
At Novalé, waterproofing is treated as a non-negotiable compliance step rather than a line item to be minimised. Every bathroom renovation is waterproofed to AS3740, inspected and tested before tiling proceeds, and backed by Novalé’s 10-year waterproofing guarantee – well beyond the industry standard most companies offer. You can read more about our broader quality standards, including our ISO 9001 certification, and find answers to common renovation questions on our FAQs page.
If you’re planning a bathroom renovation and want the confidence that comes with a company that treats waterproofing as seriously as the tiles you’ll actually see, book a free consultation with Novalé’s design team, or call 1800 NOVALÉ. Visit novale.com.au to get started.
