Wet-area waterproofing in Wagga Wagga.

In New South Wales, waterproofing an internal wet area is not general handyman work. It is licensed work, governed by the National Construction Code and Australian Standard AS 3740, because it is the single most common building defect in the state and the most expensive to fix once it goes wrong. We hold the waterproofing licence, we work to the standard, and we hand you a certificate and a set of photos of the cured membrane so the job is documented for your records, your insurer and any future sale of the home.

The reason it matters so much in Wagga specifically comes down to how local homes are built and how the climate moves them. A timber-floored home in Turvey Park or Kooringal has a floor that flexes; a brick-veneer in Lake Albert or Bourkelands shares a wall with the bedroom next door; and a new slab out at Estella or Boorooma can shrink across a long, dry Riverina summer. A membrane that is simply painted into the corners with no bond breaker cracks the first time the structure moves, and from that moment the water has a path. Done properly, with bond breakers at every internal corner, the membrane flexes with the building and keeps the water in the shower where it belongs.

How we waterproof to AS 3740.

The standard sets out the order and we follow it without shortcuts. We prepare and prime the substrate, install bond breakers and reinforcing at all internal corners and the floor-to-wall junctions, flash the floor waste and any pipe penetrations, then apply the membrane to the full shower floor and walls to the required height, dressing it into the floor and turning it up behind the hob or forming a hobless fall. The membrane is then left to fully cure before any tiling begins, because tiling onto a green membrane is one of the classic ways a wet area fails. Every stage is photographed for your file.

What it costs, and what a failure costs.

Standalone waterproofing for a Wagga bathroom, where another trade is tiling, typically runs $600 to $1,400 in 2026 depending on the size of the wet area and the number of penetrations. Worked example: a full shower recess plus the whole bathroom floor in a Kooringal renovation, including corners, hob and waste flashing, came to $1,150 with the certificate. Set that against the cost of a failure, where a leak into the adjoining bedroom of a timber-floored home meant stripping tiles, drying out rotted bearers and re-waterproofing for well over $9,000, and the value of getting the membrane right the first time is obvious.

Does a bathroom in NSW legally have to be waterproofed?

Yes. Under the National Construction Code and AS 3740, wet areas in a NSW home must be waterproofed, and in NSW internal wet-area waterproofing is licensed work. We hold that licence, work to AS 3740 and provide a certificate and photo record.

How much does it cost to waterproof a bathroom in Wagga?

Standalone waterproofing typically costs $600 to $1,400 for a standard Wagga bathroom in 2026, depending on the wet-area size, penetrations and whether the whole floor or just the shower is treated.

What happens if waterproofing fails?

Water tracks under the tiles into the floor, framing and often the next room. In a timber-floored home that means rot and a springy floor. Repair means stripping tiles, drying the structure and re-waterproofing, far dearer than doing it right once.

Can you waterproof without removing the tiles?

Generally no. The membrane has to sit under the tiles, so a true re-waterproof means lifting tiles in the affected area. We will not sell a surface sealer as a permanent fix, and we will tell you honestly if the real problem is just cracked grout or silicone.