Late winter is our busiest stretch for mould calls in Sydney. Between mid-July and the end of August the phone runs hot with tenants who've pulled a wardrobe away from the wall and found a grey-green bloom the size of a dinner plate. If you're vacating and trying to work out how to remove mould before your end of lease inspection in Sydney, the honest answer is that timing matters as much as product. Start a week out. Mould treated the morning of handover is still damp, still faintly grey, and still very photographable.
We've cleaned thousands of exit jobs across the Inner West, Eastern Suburbs and the Hills. Below is what actually works on Sydney's winter mould, what it costs in 2026, and where agents point their phone cameras.
Why does mould take over Sydney rentals every winter?
It's condensation, almost always. Sydney's relative humidity sits in the 65–80% range through July and August, and the older housing stock — 1960s and '70s red-brick walk-ups in Randwick, Ashfield, Kogarah, Federation semis in Marrickville — has cold, uninsulated external walls. Warm indoor air hits a cold surface, water forms, and mould spores that are floating around your flat regardless finally get the moisture they need.
Three culprits show up on nearly every job:
- Exhaust fans that vent into the ceiling cavity rather than outside. Common in older strata blocks. The steam has nowhere to go, so it settles on the ceiling and cornices.
- South-facing bedroom walls with a wardrobe pushed flat against them. No airflow behind the unit, cold plasterboard, damp winter clothing hung inside. That's why the back panel and the wall behind it go first.
- Single-glazed aluminium windows. Water runs down the glass overnight, pools in the track, and the sill and reveal start spotting by August.
Drying clothes indoors on a rack makes all three worse. A single load of washing releases around two litres of water into the air.
Is the mould your problem or the landlord's?
In NSW, the split roughly follows the cause. Mould from a structural fault — a leaking shower membrane, a failed roof, rising damp, a burst pipe in the wall cavity — sits with the landlord, who has to provide and maintain premises fit to live in. Mould from condensation and everyday living is generally treated as tenant cleaning, especially if you never reported a problem.
That last bit is where people come unstuck. If you emailed the agent in June about the shower leaking behind the tiles and have the reply, you're in a strong position at the final inspection. If the first anyone hears about it is on exit report day, expect a cleaning claim. So dig out your ingoing condition report and check whether mould was already noted, and put anything unresolved in writing to the agent before you hand back the keys. NSW Fair Trading's dispute process runs on evidence, not memory.
Either way, surface mould you can reach still needs cleaning. Agents don't hand back bonds on the strength of a legal argument alone.
How do you remove bathroom mould before the final inspection?
Bathrooms carry most of the risk because that's where silicone, grout and ceiling paint all meet steam. Work in this order.
1. Ventilate and mask up
Window open, fan on, P2 mask and rubber gloves. Disturbing a colony puts spores in the air. And never mix bleach with vinegar or any ammonia-based cleaner — the fumes are genuinely dangerous.
2. Choose the right killer for the surface
On tiles, glass and non-porous surfaces, a bleach-based spray like Exit Mould or White King Mould Remover works fast, roughly $7–$12 at Woolies. On painted plasterboard, ceilings and timber, bleach only lightens the stain and leaves the roots behind — use clove oil instead. Quarter of a teaspoon of clove oil per litre of water in a spray bottle, or the pre-mixed Concrobium and Glen 20-style mould control products at $15–$25.
3. Let it dwell
This is the step everyone skips. Spray, walk away for 20 minutes, come back. Scrubbing straight away just smears it.
4. Wipe, don't blast
Microfibre cloth, light pressure, one direction. On ceilings, aggressive scrubbing peels the paint and you've traded a mould note for a damage note.
5. Deal with the silicone honestly
Black mould inside shower silicone is under the surface. No spray reaches it. Cut it out with a Stanley knife, clean the channel with metho, let it dry fully, and re-run a bead of Selleys Wet Area silicone — about $18–$25 a cartridge. Half an hour of work, and it's the single change that makes a tired bathroom read as clean.
6. Dry everything
Towel it off, then leave the fan running or a fan heater pointed at the area for an hour. Damp surfaces re-spot within days.
Pro tip from our crews: pull the exhaust fan cover off (usually two clips), soak it in hot water with a squirt of dishwashing liquid, and wipe the visible fan blades. Agents lift those covers. A furred-up grille reads as "not cleaned" faster than almost anything else in the room.
What's the fix for wardrobe, wall and ceiling mould?
Empty the wardrobe completely, including the shelf above. Vacuum the interior with a HEPA-filter vacuum first — dry-wiping just spreads spores across the melamine. Then wipe every surface with the clove oil solution, including the back panel, the rail and the underside of shelves.
For the wall behind, if the plasterboard is spotted but firm, clove oil and a gentle wipe usually clears it. If it's soft, bubbling, or the paint lifts when you touch it, stop. That's a moisture problem behind the wall and it's a maintenance issue — photograph it and report it in writing rather than trying to patch over it.
Carpet along the skirting in a mouldy bedroom often holds a musty smell even after the wall is clean. That's a job for hot-water extraction, not a rental shampooer. Our carpet steam cleaning gets booked with a lot of winter exit cleans for exactly this reason.
What does mould cleaning cost in Sydney in 2026?
| Job | DIY cost & time | Professional (Sydney, 2026) |
|---|---|---|
| Bathroom ceiling & wall spotting | $15–$25, about 1 hour | Usually included in a bond clean |
| Cut out & replace shower silicone | $25–$40, 45 min + 24 hr cure | $120–$220 handyman call-out |
| Grout re-whitening (one shower) | $20 grout pen, 1–2 hours | $180–$350 grout restoration |
| Wardrobe + wall behind | $10, 40 minutes | Included in a deep clean |
| Full exit clean, 2-bed unit | 7–10 hours of your weekend | $350–$520 |
| Specialist mould remediation | Not a DIY job | $450–$1,400 |
Most winter exit jobs sit in that bond clean row. Genuine remediation — the air-scrubber, containment-sheeting kind — is only needed where there's active water ingress, and that's the owner's cost, not yours. Current rates for our own work are on the pricing page.
What do Sydney agents actually flag for mould on an exit report?
From the reports we see come back, the repeat offenders are:
- Shower silicone and the grout line where the wall meets the base
- Bathroom ceiling and cornice, particularly directly above the shower head
- Exhaust fan cover and grille
- Window tracks, sills and reveals in bedrooms
- Wardrobe back panels and the rail ends
- Under-sink cabinets in kitchen and bathroom, where a slow tap drip has been sitting
- The rubber seal of the dishwasher and the washing machine door
Work through the full room-by-room list on our bond clean checklist before you book the inspection. Ten minutes with that list beats a re-clean notice a fortnight later.
How do you stop it coming back before handover?
There's often a two or three week gap between your last clean and the agent's inspection, and in a cold empty flat mould can return in that window. Keep a dehumidifier running if you have one — a decent 10L unit is $180–$280 at Bunnings or Kmart and it's worth borrowing one for a fortnight. Otherwise leave two DampRid tubs going ($8 each), keep internal doors and wardrobe doors open for airflow, and if you can safely leave a window on the security latch, do it.
Photograph every treated area on the day you finish, with the date visible. If the agent later claims mould, you can show what the property looked like at handover.
And if the bathroom's beyond a weekend's effort — plenty of 40-year-old Sydney bathrooms are — book it out. Our end of lease cleaning includes mould treatment across bathrooms, wardrobes and window reveals as standard, and if your agent flags anything on the exit report we come back and re-clean it free within 72 hours. Give us a call on 0468 490 764 or send through the details of your place and we'll tell you honestly whether it's a clean or a maintenance job.
More on this: End of Lease Cleaning in Sydney.
