Mould Problem in Rental Properties

In New South Wales, landlords are legally required to provide and maintain rental properties in a reasonable state of repair under the Residential Tenancies Act 2010. This obligation extends to addressing mould problems caused by structural defects, inadequate ventilation systems, water leaks, or building maintenance failures.

However, tenants also have responsibilities. They must maintain reasonable cleanliness, report issues promptly, and take reasonable steps to ventilate the property. When mould arises purely from tenant lifestyle factors like drying clothes indoors without ventilation or failing to use exhaust fans, the tenant may be held responsible.

• Landlords must fix structural causes: leaking roofs, pipes, windows, gutters, and drainage
• Landlords must ensure adequate ventilation systems are installed and functional
• Tenants must report mould and maintenance issues in writing as soon as discovered
• Tenants must use available ventilation like exhaust fans and windows appropriately
• Tenants must maintain reasonable standards of cleanliness and air circulation

Rental properties in Sydney are particularly vulnerable to mould because many older buildings lack modern ventilation systems, and units in apartment complexes often have limited natural airflow. Identifying the underlying cause is crucial to determining responsibility.

Structural issues include leaking roofs, damaged gutters, cracked external walls, faulty plumbing, and poorly sealed windows or doors. These problems allow water to penetrate the building envelope and create persistent moisture that tenants cannot control regardless of their behaviour.

Lifestyle factors include excessive steam from cooking and bathing without using exhaust fans, drying laundry indoors without ventilation, blocking air vents with furniture, and keeping windows closed for extended periods. When these behaviours occur in properties with marginal ventilation, mould can establish quickly.

Proper documentation is essential if you need to escalate a mould complaint to the NSW Civil and Administrative Tribunal or negotiate with your landlord. Begin documenting as soon as you notice the first signs of mould growth.

Take clear, dated photographs of all affected areas from multiple angles. Include wide shots showing the location within the room and close-ups showing the extent of growth. If possible, include a ruler or coin in photos to demonstrate the scale of affected areas.

Keep copies of all correspondence with your landlord or property manager. Send maintenance requests in writing via email or through official rental portals so you have timestamped records. Follow up any verbal conversations with written summaries sent to the landlord.

• Photograph mould growth with date stamps showing progression over time
• Document any water leaks, condensation patterns, or visible building defects
• Keep records of any health symptoms experienced by household members
• Save all written correspondence including emails, texts, and maintenance requests
• Note dates when issues were reported and any promised action by the landlord
• Obtain quotes from professional mould assessors if the landlord refuses to act

The formal process begins with a written maintenance request to your landlord or property manager. Describe the mould location, extent, and any suspected causes like leaks or condensation. Request an inspection and necessary repairs within a reasonable timeframe, typically 14 days for non-urgent issues.

If the landlord does not respond or refuses to act, send a formal breach notice using the appropriate form from NSW Fair Trading. This notice gives the landlord a further 14 days to address the issue and creates an official record of non-compliance.

If the problem remains unresolved after the breach notice period, tenants can apply to the NSW Civil and Administrative Tribunal for orders requiring the landlord to carry out repairs. The tribunal has authority to order compensation for tenants who suffered health effects or property damage.

Landlords in New South Wales must maintain rental properties in a condition fit for habitation. When mould growth results from structural defects, inadequate building systems, or maintenance failures, the landlord is legally obligated to remedy the situation promptly.

This includes arranging professional mould inspections if the extent is unclear, engaging qualified contractors to repair water leaks or ventilation deficiencies, and covering the cost of professional mould remediation when the cause relates to building defects.

Failure to meet these obligations can result in tribunal orders, compensation payments to tenants, and in severe cases, rental rebates or early lease termination without penalty to the tenant. Landlords who ignore serious mould issues risk significant legal and financial consequences.

• Respond to tenant maintenance requests within reasonable timeframes
• Arrange professional assessment when the cause or extent is unclear
• Repair structural defects causing moisture intrusion promptly
• Engage qualified professionals for mould remediation if extensive growth exists
• Ensure adequate ventilation systems are installed and operational
• Provide temporary accommodation if remediation requires the property to be vacated

Tenants cannot simply stop paying rent because mould exists. However, if the property becomes uninhabitable due to severe mould that poses health risks, and the landlord has been given reasonable opportunity to fix the issue but has not acted, tenants may have grounds to apply for early lease termination.

The NSW Civil and Administrative Tribunal can order rent reductions while mould remediation is underway, compensation for damaged belongings, or permission for tenants to terminate the lease without financial penalty. These remedies depend on demonstrating that the landlord failed to meet legal obligations despite proper notice.

Before taking any action that could be considered a breach of your lease, seek advice from the Tenants Union of NSW or a tenancy advocate. Incorrect procedures can weaken your legal position even when the mould problem is legitimate.

Prevention requires cooperation between landlords and tenants. Landlords should conduct regular property inspections to identify early signs of water damage, ensure gutters and drainage systems are maintained, and upgrade inadequate ventilation in bathrooms and kitchens where necessary.

Tenants can significantly reduce mould risk by using exhaust fans every time they cook or shower, opening windows for at least 30 minutes daily when weather permits, keeping furniture away from external walls to allow air circulation, and wiping condensation from windows and surfaces promptly.

• Use exhaust fans in bathrooms for at least 20 minutes after showering
• Open windows during and after cooking to release moisture
• Avoid drying laundry indoors unless a vented dryer is used
• Maintain indoor humidity below 55 percent using dehumidifiers if necessary
• Report any leaks, damp patches, or condensation issues immediately
• Clean bathroom and kitchen surfaces regularly to prevent surface mould establishing

When responsibility for mould is disputed, an independent professional assessment can provide clarity. Forensic mould inspections identify the underlying moisture source, determine whether building defects or lifestyle factors are primarily responsible, and recommend appropriate remediation methods.

Nanotise provides comprehensive mould assessments for rental properties throughout Sydney. Our inspections use thermal imaging and moisture meters to detect hidden water intrusion that may not be visible. We provide detailed reports that clearly distinguish between structural causes and lifestyle factors, helping landlords and tenants resolve disputes based on factual evidence.

Surface cleaning of small mould patches on non-porous surfaces like tiles can be performed by tenants as part of routine maintenance. However, extensive mould growth, growth on porous materials like drywall, or recurring mould despite cleaning all require professional remediation.

Professional mould removal addresses the root cause, removes affected materials where necessary, treats surfaces with hospital-grade fungicides, and applies protective barriers to prevent recurrence. Attempting DIY remediation of serious mould problems often spreads spores and fails to address the underlying moisture source.

Nanotise uses TGA-registered treatments and applies CRX nanotechnology barrier protection that provides long-term prevention. Our 16 years of experience in Sydney rental properties means we understand both the technical and legal aspects of mould remediation in tenanted homes.