A mould bond dispute happens when a landlord tries to claim some or all of a tenant’s bond to cover mould-related cleaning, repainting or repairs at the end of a tenancy, and the tenant disagrees that they’re responsible for it. These disputes are common in the Illawarra given the region’s older housing stock and coastal humidity, and they nearly always come down to one question at NCAT: whose evidence is stronger about what actually caused the mould? This guide covers what evidence carries weight for either side and how to build a case that holds up. It is general information only and is not legal advice: contact the Tenants’ Union of NSW or a licensed lawyer for advice specific to your situation.
Why Bond Disputes Over Mould Are So Common
Mould sits in a genuinely contested category under NSW tenancy law. If it stems from a building fault, a leaking roof, a blocked subfloor vent, a bathroom fan ducted into the ceiling cavity instead of outside, that’s a landlord repair obligation, and a bond claim for cleaning or repainting it is unlikely to succeed. If it stems clearly from how the property was used, drying laundry indoors constantly with no ventilation, never using a working exhaust fan, that’s closer to tenant responsibility, and a bond claim has a stronger footing.
The problem is that “clearly” is doing a lot of work in that sentence. Most real bond disputes involve some mix of building condition and occupant behaviour, and without documentation from before the tenancy started, there’s no baseline to compare against. That’s why these disputes end up at the NSW Civil and Administrative Tribunal (NCAT) so often: without a clear record, both sides are left arguing over memory and interpretation.
What Evidence Actually Carries Weight
The table below reflects how these disputes tend to play out in practice, based on the kind of documentation that gives a tribunal something concrete to work from rather than competing verbal accounts.
| Evidence type | Weight in a bond dispute |
|---|---|
| Dated ingoing condition report with photos | High |
| Independent written mould or moisture inspection report | High |
| Dated photos taken during the tenancy showing when mould first appeared | High |
| Written repair requests and the landlord’s response (or lack of one) | High |
| Routine inspection reports through the tenancy | Medium-high |
| Tenant’s account of ventilation habits, cleaning routine, etc | Medium |
| Verbal claims with no supporting documentation from either side | Low |
Notice that the strongest evidence in every category is something written and dated, created at or near the time in question, rather than reconstructed afterward. A tenant who took photos when they first noticed mould, three months into the tenancy, has a far stronger position than one who only photographs it at the final inspection. A landlord who documented the property’s condition thoroughly before handover has a far stronger position than one relying on memory of what the walls looked like eighteen months ago.
For Tenants: Building Your Case Before a Bond Claim Is Even Made
The best time to protect yourself in a mould bond dispute is well before the final inspection, ideally from the day you move in:
- Photograph the property thoroughly on move-in, room by room, including any existing damp, staining or mould, even minor. This becomes your baseline.
- Report mould in writing as soon as you notice it, with photos and a date, rather than waiting to see if it goes away. A written repair request that the landlord ignored or delayed on is some of the strongest evidence available at NCAT.
- Keep records of ventilation habits where relevant, particularly if you’ve specifically raised concerns about an inadequate or non-functioning exhaust fan and asked for it to be fixed.
- Get an independent mould inspection if a dispute looks likely, especially before vacating, since an inspection report from a party with no stake in the outcome carries real weight against a landlord’s assumption that the mould was tenant-caused.
Our guide to taking a mould claim to NCAT covers the escalation process in more detail if a bond dispute turns into a formal tribunal matter, including what NCAT can actually order and when a lawyer becomes necessary rather than optional.
For Landlords: What Protects a Legitimate Bond Claim
A landlord with a genuine case that tenant behaviour caused or worsened mould is in a much stronger position with the right documentation on file:
- A dated ingoing condition report showing the property was mould-free (or noting exactly what pre-existing condition looked like) at the start of the tenancy
- Routine inspection records through the tenancy that note the property’s condition at each visit, not just a box ticked
- A functioning, correctly ducted exhaust fan confirmed at the start of the tenancy, since a bond claim for mould is much harder to sustain if the ventilation provided wasn’t adequate in the first place
- Any tenant correspondence about mould, drying habits or maintenance requests, kept on file rather than only referenced from memory
Our landlord mould checklist for NSW rentals sets out the ingoing, routine and between-tenancy checks that build exactly this kind of record, run properly rather than as a box-ticking exercise.
The Role of an Independent Mould Inspection
For either side, an independent mould inspection and moisture investigation is often the single document that resolves a genuinely disputed bond claim, or at least narrows what’s actually being argued about. It’s objective, it comes from a party with no financial stake in the tenancy, and it records facts, moisture readings, probable cause, extent, that are difficult to dispute from either side. A report establishing that mould stems from a structural moisture source removes the argument entirely; a report finding no structural cause and consistent surface condensation patterns strengthens a landlord’s position instead. Either way, it’s a more useful document at NCAT than two competing verbal accounts.
When a Bond Dispute Needs a Lawyer, Not Just Documentation
Most straightforward bond disputes over mould can be resolved through NSW Fair Trading’s bond claim process without ever reaching a hearing. Legal advice becomes worth the cost when the claimed amount is substantial, when there’s a genuine dispute about a structural cause the landlord denies, or when either party has been through a prior dispute during the same tenancy that could affect how the claim is viewed. Contact the Tenants’ Union of NSW for free preliminary advice, or a licensed lawyer for anything involving significant money or legal complexity.
Get a free quote if you need an independent mould inspection report to support a bond claim or dispute, whether you’re a tenant, a landlord, or a property manager caught in the middle.
FAQs
Can a landlord automatically keep bond money for mould?
No. A landlord needs to establish that the mould was caused by the tenant’s actions rather than a building defect, and the NSW Rental Bonds Online process requires the tenant’s agreement or a Tribunal order before bond funds are released for a disputed claim. Without agreement, the matter goes to NCAT.
What if neither side has strong documentation?
This is common and makes for a genuinely harder case for both parties. NCAT will weigh whatever evidence exists, including verbal testimony, but a case with little documentation is less predictable in outcome than one with a clear paper trail. This is exactly why building a record early, on both sides, is worth the small effort it takes.
Does an independent mould inspection favour the tenant or the landlord?
Neither, by design. It reports what’s actually found: the moisture source, the extent, and whether it’s consistent with a structural fault or with occupant behaviour. That’s precisely why it tends to be persuasive at NCAT regardless of which party commissions it.
How much bond can be claimed for mould-related cleaning?
There’s no fixed figure; it depends on the actual cost of professional cleaning, repainting or repair, and whether that cost is a reasonable response to genuine tenant-caused damage rather than fair wear and tear or a building fault. Excessive or inflated claims are just as likely to be challenged successfully as claims with no basis at all.
Should I get an inspection before or after lodging a bond dispute?
Before, if possible. Commissioning an inspection while the property is still accessible and the situation is fresh produces a more useful report than trying to establish facts after the property has been re-let or repainted over.