What's Included in the Price
For a reseal: removal of deteriorated silicone and grout, joint preparation, and reapplication with fresh sealant. Materials include bathroom-grade silicone and grout. In Brisbane's humid conditions, epoxy grout is worth considering for the shower floor: it is non-porous, resists mould without sealing, and lasts roughly twice as long as cement-based alternatives like Davco Sanitized Colorgrout or Ardex FG8.
For a membrane replacement: tile removal, stripping the failed waterproofing, substrate cleaning and repair, new membrane compliant with AS 3740:2021 Waterproofing of Domestic Wet Areas, pre-tiling inspection, and retiling. Liquid-applied membranes (Crommelin, Ardex, Davco) are standard. Two coats minimum, with 24-hour cure between each. Brisbane's warmth helps cure times, but high humidity can slow drying if ventilation is poor.
A diagnostic callout fee ($80–$150) applies. Flood testing is available to confirm whether the membrane has actually failed before committing to a full strip-out. Cosmetic repair to ceilings, walls, or adjacent rooms is not included and needs a separate trade.
What Affects the Cost
- Surface vs membrane failure. Cracked grout and peeling silicone is a surface fix costing a few hundred dollars. A failed membrane is a full strip-out costing several thousand. Getting a proper diagnosis first is the most important step.
- Slab vs raised floor. On a concrete slab (most post-1970s Brisbane homes), water from a failed membrane travels sideways into adjacent rooms rather than down through the floor. On a raised Queenslander with timber floors, it drops through and damages the ceiling below. Both scenarios have different repair profiles.
- Mould extent. Brisbane's humidity accelerates mould growth when water gets behind tiles. If mould has spread from grout joints into wall framing or plasterboard, remediation adds to the scope and cost.
- Grout type. Epoxy regrout ($800–$1,500) is particularly worth the premium in Brisbane's climate. Cement-based grout ($600–$1,200) absorbs moisture in humid conditions and promotes mould growth.
- Shower size. Larger showers cost more to strip and retile. A compact ensuite shower is quicker than a full walk-in.
- Previous repairs. If regrouting or injection sealing has already failed to fix the leak, the membrane is the problem. The next step is a full strip-out.
- Tile availability. If the existing tiles are discontinued and cannot be matched, a partial repair becomes a full retile.
A silicone and grout reseal on a standard shower hob in a modern North Lakes or Springfield home sits toward $250. A full strip-out in an older Red Hill Queenslander with timber floors, mould remediation, membrane replacement, and retiling pushes toward $3,600.
Brisbane-Specific Considerations
Brisbane's subtropical conditions and housing styles shape how shower leaks present and what they cost to fix.
Slab-on-ground homes (Sunnybank, Eight Mile Plains, Springfield, Carindale). Most post-1970s Brisbane homes sit on concrete slabs. When a shower membrane fails on a slab, water does not drain downward. Instead, it tracks sideways along the slab surface, appearing as damp patches or tile lifting in adjacent rooms, hallways, or even bedrooms. The visible damage can show up metres from the shower itself. A flood test is the most reliable way to confirm the shower is the source before committing to tile removal. On the positive side, slab homes have no timber subfloor to rot, so the structural risk is lower and repair scope is more predictable.
Queenslanders and high-set homes (Paddington, Red Hill, Ashgrove, Woolloongabba). These homes have timber-framed bathroom floors. When the shower leaks, water drops through the floor and stains the ceiling of the room below. Brisbane's humidity means this staining often appears within weeks of a membrane failure, much faster than in cooler climates. The upside is earlier detection, which can limit the extent of timber damage. In Paddington and Ashgrove, waterproofers frequently find that the timber framing is still sound if the homeowner acted within a few months of noticing the first signs.
Humidity and mould. Brisbane's warm, humid conditions promote rapid mould growth behind tiles when moisture gets in. A shower leak that might take months to produce visible mould in Melbourne can produce it within weeks in Brisbane. Black spots in grout joints or a persistent musty smell are signs the problem extends beyond the tile surface. If mould has spread into wall framing, remediation by a licenced mould assessor may be needed before waterproofing work begins.
QBCC compliance. If the membrane is replaced, the work requires a QBCC waterproofing licence holder and a compliance certificate. The pre-tiling inspection is mandatory. This certificate protects you if problems arise later and is required for insurance claims related to the repair.
Hiring a Licensed Waterproofer in QLD
Shower leak repair involving membrane work requires a QBCC-licensed waterproofer holding a Certificate III in Construction Waterproofing. Verify licences on the QBCC licensee register.
A good waterproofer will offer a flood test before recommending a full strip-out, provide a written quote separating diagnostic, waterproofing, and retiling costs, and issue a compliance certificate on completion.
Worth checking:
- Current QBCC waterproofing licence number (verify on the QBCC register)
- Flood test or leak detection offered before committing to a full strip-out
- QBCC compliance certificate issued on completion
- Pre-tiling inspection confirmed if membrane is replaced
- Written scope clarifying whether retiling is included or quoted separately
How We Calculate
Estimates are based on surveyed rates from QBCC-licensed waterproofers in the Brisbane metropolitan area, adjusted for typical construction types in QLD. All prices include GST. Figures cover standard residential shower leak repairs and do not include cosmetic repairs to adjacent rooms or full bathroom waterproofing.