Mould in Rental Properties: Rights and Responsibilities Under NZ Law

Mould in rental properties is one of the most common disputes between landlords and tenants in New Zealand. Understanding the legal framework helps both parties resolve issues fairly and efficiently.

The Healthy Homes Standards

Introduced in 2019, the Healthy Homes Standards set minimum requirements for rental properties in five areas: heating, insulation, ventilation, moisture ingress and drainage, and draught stopping. The ventilation and moisture ingress standards are particularly relevant to mould prevention.

Ventilation Standard

Rental properties must have openable windows in living rooms, dining rooms, kitchens, and bedrooms. Kitchens and bathrooms must have extractor fans that vent to the outside. These requirements are designed to remove moisture at its source — cooking, showering, and everyday occupancy.

Moisture Ingress and Drainage Standard

Landlords must ensure rental properties have adequate drainage and that water does not enter the home. This includes functioning gutters, downpipes, and ground drainage. If a property has an enclosed subfloor, a ground moisture barrier must be installed where reasonably practicable.

Landlord Responsibilities

Under the Residential Tenancies Act 1986, landlords must:

• Provide and maintain the premises in a reasonable state of repair
• Comply with all building, health, and safety requirements
• Address any mould caused by structural issues, leaks, or inadequate ventilation
• Respond to tenant notifications about mould promptly

Tenant Responsibilities

Tenants also have obligations:

• Keep the premises reasonably clean and tidy
• Use ventilation provided (extractor fans, opening windows)
• Notify the landlord of any damage or maintenance issues, including mould
• Not damage or alter the premises without permission

When Mould Becomes a Dispute

Disputes often arise over the cause of mould. If mould results from a structural issue (leaking roof, rising damp, failed waterproofing), the landlord is responsible. If mould results from tenant behaviour (never opening windows, drying laundry indoors without ventilation, not using extractor fans), the tenant may bear some responsibility.

The Tenancy Tribunal considers evidence from both parties. Professional mould assessment reports that identify the moisture source can be decisive.

Practical Steps for Landlords

• Conduct regular property inspections (with appropriate notice)
• Address maintenance issues promptly when notified
• Consider installing humidity-activated extractor fans that run automatically
• Provide dehumidifiers in particularly damp properties
• Document all maintenance and communications

Practical Steps for Tenants

• Notify the landlord in writing at the first sign of mould
• Use ventilation as intended — extractor fans, windows
• Wipe condensation off windows and sills daily
• Avoid drying laundry indoors without ventilation
• Keep furniture away from external walls to allow airflow

Professional Mould Services for Rental Properties

iDry Restorations provides mould inspection, reporting, and remediation for rental properties across Auckland. Our reports clearly identify the moisture source and the extent of mould — information that is valuable for both landlords and tenants in resolving disputes.

For professional mould services, call 0800 452 199 or visit iDry Restorations Mould Remediation.