Mould at end of lease is one of the more common points of conflict in NSW bond disputes, but the question of who is responsible turns on a single distinction: is the mould the result of a tenant’s failure to ventilate and maintain, or the result of a structural moisture source the landlord was obliged to fix? Getting your documentation right before you hand the keys back is the most practical protection a tenant has. This is general information only and is not legal advice: contact the Tenants’ Union of NSW for advice on your specific situation.
What a vacate clean legitimately includes
A tenant is expected to return the premises in a condition that is as close as reasonably practicable to the condition at the start of the tenancy, taking into account fair wear and tear. A professional vacate clean typically includes:
- All hard surfaces wiped down: benchtops, shelves, skirting boards, door frames and window sills
- Bathroom and kitchen tiles, grout, fixtures and fittings cleaned to a reasonable standard
- Floors vacuumed or mopped
- Ovens, rangehoods and appliances cleaned
- Windows cleaned inside
For mould specifically: surface mould on tiles and grout, window sills and non-porous surfaces that responds to cleaning is generally within the tenant’s obligation to address as part of a vacate clean. The standard is that it should be clean at handover, not that it must be in better condition than at move-in.
The ingoing condition report is the benchmark. If the grout was already stained at move-in and that staining was documented in the report, you cannot be required to make it better than it was.
See NSW Fair Trading, end of tenancy for the legislative framework that applies.
When mould at handover is the tenant’s issue
Not all mould at end of lease is the landlord’s problem. Surface condensation mould, the kind that grows on tiles, grout and window sills when bathroom ventilation is inadequate or windows are kept perpetually closed, is generally considered within the tenant’s reasonable maintenance responsibility.
If the mould:
- Is on non-porous surfaces (glazed tiles, glass, sealed paint) and has not penetrated the material
- Responds to cleaning with a damp cloth and a mild cleaning product
- Is in a location where condensation is expected (bathroom ceiling, kitchen splashback)
- Was not present at the start of the tenancy per the condition report
… then cleaning it as part of the vacate is the appropriate step. If it’s cleaned to a reasonable standard at handover, a landlord claiming a bond deduction for the same mould needs to demonstrate that the cleaning was inadequate.
When it isn’t (structural/ongoing damp)
Where mould has grown because of a structural moisture source, the picture changes entirely. A landlord cannot fairly charge a tenant for mould that resulted from a defect the landlord failed to repair.
Structural sources that place the obligation on the landlord include:
- A leaking roof where water enters the ceiling space or walls
- A plumbing defect (leaking pipe, failed waste trap) that has caused concealed water damage
- Rising damp through a slab or footings
- Waterproofing failure in a shower that was not tenant-caused
- Inadequate subfloor or ceiling ventilation that the landlord was aware of and did not address
The key documentation question is: did you report it in writing? If you sent a written maintenance request noting the mould or the moisture source, and the landlord failed to carry out the repair, the resulting mould damage is not your liability. See our mould in rentals guide for the full obligations that apply during a tenancy.
See our rising damp vs condensation guide for how to distinguish a structural moisture problem from ordinary condensation, which matters when a landlord claims the mould was occupant-caused.
Documenting the state at move-out
Your documentation at move-out is your primary protection. Take it seriously even when the relationship with your landlord or agent has been good.
Steps to take on the day or the day before:
- Walk through every room and record video footage continuously, narrating what you see as you go. Date and time stamp it.
- Take still photographs of any areas with mould, any areas where mould was present and has been cleaned, and any areas where mould remains because it is from a structural source.
- Photograph the bathroom fan (if it was inadequate or non-functional, document this), any visible moisture staining and any areas you flagged in writing during the tenancy.
- If there is mould that you believe is structural and not your responsibility, note this in writing to the agent on handover day and retain a copy.
- Retain copies of every maintenance request, every written response from the landlord or agent, and the ingoing condition report.
See our tenant photo evidence guide for the specific documentation approach that is most useful in a bond dispute.
Contesting a bond deduction
If the landlord lodges a claim against your bond for mould remediation that you believe was not your responsibility, you can contest it. The process in NSW:
- When Fair Trading NSW advises you of the claim, you have a set period to respond (check the current timeframe on the Fair Trading website).
- Lodge your contest through the Rental Bond Board online system or in person.
- If the parties cannot agree, Fair Trading NSW may refer the matter to NCAT.
Your evidence bundle: the ingoing condition report, your move-out photos and video, written maintenance requests showing the structural source and the landlord’s failure to repair, and any other documentation that establishes the mould was not within your control.
See our NCAT mould claim guide if the dispute is heading to tribunal.
| Mould type at handover | Tenant responsibility? |
|---|---|
| Surface condensation, cleaned to standard | No deduction warranted |
| Surface condensation, not cleaned | Deduction may be warranted |
| Structural source reported in writing, not repaired | Landlord responsibility |
| Structural source never reported | Disputed (may be shared) |
| Mould under carpet from ongoing leak | Landlord responsibility if defect was known |
| Mould on personal belongings | Generally not claimable from bond |
See our landlord mould obligations checklist for the duty framework that NCAT applies to landlords.
When an independent inspection helps
Where the mould is significant, where you and the landlord dispute the cause, or where the bond deduction being claimed is substantial, commissioning an independent mould assessment report before or during the move-out process is often the most cost-effective step you can take.
A report that establishes a structural moisture source (rising damp, roof defect, plumbing failure) removes the ambiguity the landlord is relying on. It’s objective, it’s written, and it can be submitted directly to Fair Trading mediation or NCAT.
Our mould inspection and testing service provides written reports with moisture mapping that are suitable as evidence in property disputes. Booking early, before the handover rather than after the dispute begins, gives you the clearest picture of the state of the property at the point of vacation.
The cost of the inspection may be recoverable from the landlord if you prevail in a dispute, though this depends on the specific findings and the NCAT decision. Contact us to discuss what a pre-vacate inspection would cover for your property.
If you’re in a share house situation with multiple tenants and the dispute involves how liability is apportioned between occupants, see our mould in share houses guide.
FAQs
The landlord is claiming the whole bond for mould damage. Is that reasonable?
Rarely. Bond claims must be reasonable and proportionate. Even where mould remediation is legitimately the tenant’s responsibility, the claim should reflect the actual cost of cleaning or replacement, not an inflated figure. Contest any claim that doesn’t come with itemised quotes or invoices. The Rental Bond Board requires claims to be substantiated.
I found mould under the carpet during the move-out clean. What do I do?
Document it immediately: photograph it in place before disturbing it. If there is a structural cause (slab-edge dampness, a long-running leak from an adjacent room), that’s the landlord’s problem and you should note it in writing to the agent immediately. If it appears to be from a water event that you caused (an overflowing bath or washing machine, for example), the scope of your liability is determined by the actual damage, not a blanket “replace everything” claim.
Can I be charged for mould on the ceiling if there’s no exhaust fan in the bathroom?
If there is no exhaust fan and the tenancy agreement didn’t require you to provide one, the lack of mechanical ventilation is a property feature (or defect) that the landlord was responsible for. Mould that grew because of inadequate ventilation in an already poorly ventilated space is not straightforwardly the tenant’s liability. Document the absence of a fan at move-out and note it explicitly.
What counts as a reasonable standard of cleanliness for mould at handover?
Visible surface mould on non-porous surfaces should be removed during the vacate clean. A reasonable standard means the mould is not visible to a reasonable person conducting a normal inspection in normal lighting. If it requires specialist equipment or chemical treatment to detect, it is arguably beyond the standard of a reasonable vacate clean. Deep mould penetration into grout, silicon or porous linings where cleaning alone is insufficient is a different matter, and whether it’s the tenant’s liability depends on the cause.
Related reading
- Mould in rental properties NSW
- Tenant photo evidence guide for mould disputes
- Landlord mould obligations checklist
- Taking a mould claim to NCAT
- Mould in share houses and student rentals
- Rising damp vs condensation in the Illawarra
- Mould assessment report explained
- Mould inspection and testing service