What Shower Waterproofing Involves
Shower waterproofing is the process of installing a continuous membrane system directly onto the substrate — the bare walls and floor of a shower before any tiles go on. The membrane acts as a fully sealed barrier that stops water from moving through grout lines and tile edges from ever reaching the building structure behind and beneath the shower.
In Lake Macquarie, every shower waterproofing installation must meet AS 3740 — the Australian Standard that specifies minimum wall heights, floor coverage, corner and junction treatment, penetration sealing, and mandatory flood testing before tiling begins. This applies to new showers, bathroom renovations, and remedial repairs on leaking showers alike.
The membrane itself is applied in multiple coats — a base coat across the full surface, detail bands reinforcing every corner and junction, followed by second and third coats across critical areas. Once cured, the shower is flood tested for 24 hours, and a compliance certificate is issued before any tile installation begins.
Shower Waterproofing Methods We Use
Liquid Membrane Application for Standard Showers
Liquid membrane is our go-to method for most shower waterproofing jobs across Lake Macquarie. We paint it directly onto the substrate in multiple coats — base coat first, detail bands at all corners and junctions, then second and third coats across critical areas. Once cured, it becomes a fully flexible, seamless barrier that moves with the building and withstands the constant moisture load a shower produces daily.
Sheet Membrane for Heavy Duty Waterproofing
Sheet membrane systems use pre-formed sheets bonded directly to the substrate and sealed at every seam. Where liquid membrane suits most residential showers, sheet systems deliver a heavier-duty solution for high-use or large-format showers where extra durability is the priority. Every seam and junction gets sealed to the same AS 3740 standard, giving you a robust waterproofing layer that handles the demands of heavy daily use without compromise.
Combined Systems for Maximum Protection
Combined systems pair a sheet membrane across the shower floor with a liquid membrane up the walls — leveraging the strengths of both methods where each performs best. The floor gets the heavy-duty sheet base handling constant water pooling and drain movement, while the walls get the seamless flexibility of a liquid system. For homeowners wanting the highest level of protection, this is the premium option.
Critical Areas We Waterproof in Every Shower
Every shower has specific areas where waterproofing failures start — and getting membrane coverage right across all of them is what separates a compliant installation from one that leaks within a few years.
The shower floor gets full waterproofing coverage across the entire base, with proper fall to the drain, a sealed waste connection, and a membrane extending beyond the shower threshold. The walls are taken to a minimum 1800mm height across all wet zone surfaces, including behind fixtures and fittings, where moisture penetrates constantly.
Corners and junctions are where most leaking showers start. Every floor-to-wall junction, internal corner, and external corner gets detail band reinforcement before membrane coats go on. These are the highest-risk areas in any shower,r and they get treated accordingly.
Every penetration — shower mixer, shower rose, grab rails — gets individually sealed before membrane application. Water finds the smallest unsealed gap, and in Lake Macquarie’s humid coastal environment, it finds it fast.
Shower Waterproofing for Bathroom Renovations
When you’re renovating a bathroom in Lake Macquarie, shower waterproofing isn’t something you schedule after everything else is sorted — it’s the step that everything else depends on. Tiles, fixtures, screens, and finishes all go on top of the waterproofing membrane, which means if the membrane isn’t right, nothing that comes after it is protected either.
During a bathroom renovation, waterproofing happens at the right point in the build sequence — after the substrate is prepared and any plumbing rough-in is complete, but before a single tile goes down. This is when conditions are optimal, the substrate is fully accessible, and detail bands can be properly installed at every corner, junction, and penetration. Trying to cut costs or compress the timeline by rushing through waterproofing at this stage is where most renovation leaks originate.
We work alongside bathroom renovation projects across Lake Macquarie, coordinating waterproofing installation, flood testing, and AS 3740 certification so tiling can proceed on schedule without handover issues between trades.
Leaking Shower Repair Lake Macquarie
Leaking showers are one of the most common problems we see in Lake Macquarie homes — and in most cases, the damage runs deeper than what’s visible on the surface. By the time a homeowner notices water stains on a ceiling below, soft spots in the bathroom floor, or persistent mould that keeps coming back, the moisture has usually been moving through the substrate for months. Surface fixes don’t solve it. The only lasting repair is a full strip back to bare substrate, a completely new waterproofing system installed to AS 3740, flood tested and certified before any new tiles go down.
Every leaking shower repair we carry out in Lake Macquarie follows the same process:
- Remove all tiles and strip existing waterproofing back to the substrate
- Assess and repair any timber, concrete or substrate damage found
- Install a full AS 3740-compliant membrane system with detailed bands
- Flood test for 24 hours and document results
- Issue a compliance certificate before tiling begins
Lake Macquarie’s coastal humidity means failed waterproofing deteriorates faster than in inland areas — older homes built before current standards are particularly exposed. If your shower is leaking, the longer it runs, the more damage accumulates behind walls you can’t see.
Shower Waterproofing vs Shower Sealing — What’s The Difference
| Shower Waterproofing | Shower Sealing |
|---|---|
| Waterproofing is a full membrane system installed beneath the tiles directly onto the substrate — it’s a building code requirement under AS 3740 and the only method that genuinely stops water penetrating walls and floors. Liquid or sheet membranes are applied in multiple coats, flood tested for 24 hours, and certified before tiling begins. This is what protects your home’s structure long term and what every shower in Lake Macquarie legally requires. | Shower sealing refers to applying silicone or grout sealant to the surface of an existing tiled shower — typically at junctions, grout lines, and screen edges. It’s a maintenance task, not a waterproofing solution. Sealing can slow surface moisture penetration, but does nothing for water that’s already moving behind tiles through a failed membrane. In Lake Macquarie’s humid coastal environment, sealing a shower with failed waterproofing underneath is a short-term fix that delays a much bigger problem. |
Shower Waterproofing FAQ
AS 3740 is the Australian Standard for waterproofing domestic wet areas. It sets legal minimum requirements for membrane coverage, wall heights, junction treatment, and flood testing. Any shower that doesn’t meet AS 3740 is non-compliant and puts your home’s structure and insurance at risk.
Most shower waterproofing jobs take two to three days from substrate preparation through to flood test completion and certification. Remedial jobs on leaking showers can take longer, depending on substrate damage found once tiles are removed and assessed.
Yes, every shower we waterproof gets flood tested before tiling begins. The shower base is filled with water and held for 24 hours. Results are documented and a compliance certificate is issued only after the flood test passes.
No. Applying a membrane over existing tiles doesn’t meet AS 3740 and won’t provide lasting protection. All tiles and existing waterproofing must be stripped back to bare substrate before a compliant membrane system can be properly installed and certified.
Most leaking showers in Lake Macquarie come down to failed or inadequate original waterproofing — particularly in homes built before current AS 3740 standards. Coastal humidity, salt air, and age accelerate membrane breakdown, while poor original installation is the most common cause.
Get Your Shower Waterproofing Quote in Lake Macquarie
If you’ve got a leaking shower, a bathroom renovation coming up, or a new shower that needs AS 3740-compliant waterproofing installed properly from the start, we’re the team Lake Macquarie homeowners call. We handle membrane installation, flood testing, and compliance certification on every job — no shortcuts, no skipped steps.
Call us today to book your shower waterproofing assessment or request a quote. We service Warners Bay, Belmont, Charlestown, Cardiff, Valentine, Eleebana, Redhead, Blacksmiths and all surrounding Lake Macquarie suburbs. Get your shower waterproofed the first time properly and avoid the far greater cost of fixing water damage down the track.
