Leaking shower repairs and waterproofing
How leaking showers are diagnosed and fixed in South Morang homes: regrouting, resealing, membrane replacement, sourced prices and waterproofing rules.
A leaking shower is fixed by finding where the water escapes, then either resealing the surface or replacing the membrane underneath. One Melbourne guide gives $250 to $4,000 per job for shower leak repair; the low end is a reseal, and the top end involves lifting tiles and rebuilding the waterproofing.
Where does a shower usually leak?
Water gets out of a shower in a handful of places, and each one has a different fix:
- through cracked or porous grout between the floor tiles
- along the silicone joint where the walls meet the floor or the base
- around the floor waste, where the membrane should turn down into the drain
- past the hob or the screen track onto the bathroom floor
- through the tap and mixer penetrations in the wall
- through a membrane that has split, was never applied properly, or stops short of the shower area
A dripping pipe inside the wall can look exactly like a waterproofing failure. A provider should rule out the plumbing before quoting a membrane job.
How is a shower leak diagnosed?
Expect a provider to run water in stages: first onto the floor near the waste, then against each wall, then through the mixer, watching for moisture readings to rise on the far side of the wall. A moisture meter, staining patterns and the age of the grout usually narrow it down. The Sparky Melbourne repair guide notes that a flood test to confirm a membrane failure may be charged separately from the repair.
Often the first evidence is in the room behind the shower: a skirting board that has swollen, paint bubbling at the bottom of a hallway wall, or carpet that stays damp along one edge. Ensuites backing onto a walk-in robe are worth checking inside the robe.
Which repair suits which fault?
| Repair | When it fits | Published range |
|---|---|---|
| Cement-based regrout | Grout is cracked or eroded but tiles are firm and the membrane is sound | $600 to $1,200 |
| Epoxy regrout | As above, with a harder, less porous grout | $800 to $1,500 |
| Membrane replacement and retiling | Tiles are loose or drummy, or water is passing under the tiles | $2,000 to $4,000 |
| Whole-bathroom waterproofing | The wet area is being stripped as part of a renovation | $735 to $3,675 |
The two regrout lines come from the Sparky guide above. The membrane figure is from a Melbourne tiling cost guide, and the last row comes from a Melbourne renovation cost guide. A regrout cannot repair a membrane that has failed. If the tiles are moving, new grout is likely to crack again, and a provider who says so before taking your money is worth listening to.
What does a membrane replacement involve?
The provider removes the screen, then the floor tiles and the lower wall tiles in the shower area, and takes out the old screed. Wet timber or plaster is cut out and allowed to dry. The floor is screeded to fall to the waste, the waste flange is set so the membrane can turn into it, bond breakers go into the internal corners, and a new membrane goes on in thin coats. Once it has cured it is inspected, then the area is retiled and resealed.
If the recess turns out to have a cracked moulded base rather than a tiled floor, the job becomes a shower base replacement instead.
Which rules apply to shower waterproofing?
In Victoria, shower waterproofing has to satisfy the NCC, and the deemed-to-satisfy routes are AS 3740 and the ABCB Housing Provisions. The BPC guide to waterproofing wet areas sets out the main points for houses:
- the shower floor must be waterproofed and fall to a floor waste at between 1:80 and 1:50
- an unenclosed shower is treated as covering a 1500mm radius from the shower rose connection, with a waterstop at that edge
- membranes should go on in multiple thin coats over a clean, dry substrate, since one thick coat can trap air and leave pinholes
- bond breakers are needed at wall, floor and hob junctions where the membrane is bonded
A regrout on its own is single-trade tiling work. Once the job includes waterproofing, plumbing and tiling together and passes ten thousand dollars, the provider contracting with you must be a registered builder.
What a careful provider will not do
They will not quote a full rebuild without first testing where the water goes. They will not seal clear coatings over a leak that is coming from the waste or the wall, because that hides the problem rather than fixing it. They will not retile until the frame and screed are dry. And on a home built or renovated before 1990 they will not break out wall sheeting until it has been checked for asbestos, which the Victorian Asbestos Hub recommends leaving to a licensed removalist.
Rentals and investment properties
A leaking shower in a rental often turns up through a tenant’s report of mould or a damp wall. Property managers should keep the provider’s findings, photos and moisture readings with the maintenance record, and ask whether the fix was a reseal or a membrane replacement, since the two last very different lengths of time.
What to do next
Photograph the shower floor, the silicone joints and any damage on the other side of the wall, and note how long the problem has been visible. If the leak is part of a wider plan to update the room, read the full renovation guide or the ensuite renovation page first. Your request goes to independent shower repair and waterproofing providers, who assess the leak and quote directly; this site is a referral service. Ask for a leaking shower quote and mention your suburb, including Epping or Mill Park.
Frequently asked questions
- How can I tell if my shower is leaking?
Look outside the shower: swollen skirting, flaking paint low on the wall, damp carpet, mould that keeps returning or a musty smell. Tiles that sound hollow or grout that has gone dark and soft are signs inside the recess.
- Is regrouting enough to fix a leak?
Only when the tiles are firm and the membrane underneath is intact. Grout is not waterproof on its own. If water is already getting under the tiles, regrouting tends to hide the problem for a while rather than stop it.
- Can a leak be fixed without removing tiles?
Sometimes. Resealing joints, replacing silicone or regrouting can stop surface leaks. A failed membrane, a broken waste seal or a cracked tray needs the tiles in that area lifted.
- What should a tenant do about a leaking shower?
Report it to the rental provider or agent in writing as soon as it appears, with photos, and keep a copy. Early reports limit the damage to framing and floors and make the cause easier to find.
- Could the leak be a plumbing pipe instead?
Yes. A leaking mixer body or pipe joint inside the wall can wet the same areas as a failed membrane. A provider should test the plumbing separately before quoting waterproofing work.