Mould in a Rental Property in Queensland: Landlord Responsibility

When Mould Becomes a Minimum Housing Standards Breach

Schedule 5A, section 4 of the RTRA Regulation 2009 requires rental premises in Queensland to be free from vermin, damp, and mould. Since 1 September 2024, this standard applies to every existing residential tenancy in the state — not just new leases.

A breach of this standard exposes you to a QCAT rent-reduction order, a $3,454 maximum fine under Section 185 of the RTRA Act (20 penalty units at $172.70 per unit as of 1 July 2026), and a tenant who can bypass RTA conciliation entirely and apply directly to the tribunal for an urgent repair order.

The critical question is always causation: who created the conditions that allowed the mould to grow?

Structural Mould vs Tenant-Caused Mould

The RTRA Regulation draws a clear line. You are responsible when mould results from a structural deficiency: a leaking roof, burst internal plumbing, rising subfloor dampness, defective bathroom exhaust fans, or blocked external ventilation. These are property defects that existed before the tenant moved in or developed from deteriorating infrastructure.

The tenant exception applies when mould arises from their actions or omissions — habitually closing windows, drying clothes indoors without ventilation, failing to clean food spills, or using high-humidity storage practices in enclosed rooms. Queensland law explicitly removes landlord liability in those circumstances.

The difficulty is proving which category applies, and the burden falls on you. This is where your Entry Condition Report (Form 1a) becomes essential. If you delivered the property clean, dry, and mould-free — documented with dated high-resolution photos at every moisture-prone area — you have a defensible baseline. Without that baseline, QCAT will struggle to distinguish structural from lifestyle causes, and the ruling typically goes against the landlord.

The Mould Remediation Workflow

When a tenant reports mould in writing, follow this sequence:

1. Issue an RTA Form 9 Entry Notice allowing 48 hours' notice for maintenance (the post-May 2025 minimum for repair entry).
2. Inspect and compare the current condition against your Form 1a baseline photos. Check for structural causes: water stains on ceilings or walls, damp patches near plumbing risers, blocked subfloor vents, or exhaust fans that no longer draw air.
3. If structural causes are present, engage a licensed builder or remediation specialist immediately. A QBCC-licensed contractor handles structural repairs; a plumber addresses leaking pipes. Archive every trade invoice, moisture meter reading, and inspection photo.
4. If tenant lifestyle factors are the cause, provide written ventilation guidance and request the tenant clean surface mould. You are not obligated to pay for remediation caused by the tenant, but you do need to communicate in writing and retain a copy.

Professional mould remediation for a structural issue typically runs between $500 and $3,000 depending on severity and whether plasterboard replacement is needed. Delaying this work is not a cost-saving strategy — a QCAT rent reduction of $50 to $100 per week will exceed the repair cost within months, and the RTA Investigations Unit can initiate a separate prosecution.

Building Your Defence File

Every mould dispute at QCAT turns on evidence. The landlord who walks in with a stack of dated photographs, trade invoices, and a detailed Form 1a wins. The landlord who says "it was fine when they moved in" without documentation loses.

Your mould compliance file should include the Form 1a baseline with close-up photos of bathroom ceilings, window frames, laundry areas, and subfloor access points. Add moisture meter readings if taken during inspections, copies of every Form 9 entry notice served, trade contractor invoices with scope-of-work descriptions, and written correspondence with the tenant about ventilation practices.

If you need a structured system for tracking compliance evidence across all nine Schedule 5A standards — not just mould — the Rental Minimum Standards in Queensland guide includes a pre-tenancy audit checklist and evidentiary photo indexing worksheet designed for exactly this purpose.

Common Mistakes That Lose QCAT Disputes

The most expensive mistake is ignoring mould reports. A written tenant complaint should prompt an inspection and response. For a minimum housing standards failure, the seven-day remedy period runs from service of a Form 11 Notice to Remedy Breach. If the defect is not rectified within that period, the tenant can lodge a Form 16 dispute resolution request or go directly to QCAT for an emergency repair order under Section 215 of the RTRA Act.

The second mistake is assuming cosmetic mould does not count. Even surface mould on window frames or bathroom grout can constitute a breach if it stems from a ventilation deficiency in the building design. Painting over mould without addressing the cause is not remediation — QCAT treats it as evidence of wilful neglect.

The third mistake is failing to distinguish your maintenance obligations from those of the body corporate. If you lease a strata unit and common-property defects (a shared roof leak, inadequate building ventilation) are causing mould in your lot, you remain liable to the tenant under Section 185. You must pursue the body corporate for the structural fix while offering the tenant appropriate rent adjustments or interim solutions. Body corporate inaction is not a legal defence.

Get the full Schedule 5A compliance workflow, including the mould remediation protocol, in the Queensland Rental Minimum Standards guide.

See more Queensland guides →