Ventilation standard
Proper ventilation in rental properties helps prevent mould or dampness. All rental properties must follow the ventilation standards.
Landlords who do not meet their obligations under the healthy homes standards are in breach of the Residential Tenancies Act 1986 – and may face consequences, like financial penalties of up to $7200.
Landlords who are not sure where to start, read our healthy homes toolkit for landlords.
What are the ventilation standards?
Rental homes must have openable windows in the living room, dining room, kitchen and bedrooms.. All habitable rooms in a rental property must have at least 1 window, door or skylight which opens to the outside and can be fixed in the open position.
In each room, the size of the openable windows, doors and skylights together must be at least 5% of the floor area of that room.
Each door, window or skylight must be openable and must be able to remain fixed in an open position.
All kitchens and bathrooms must either have an extractor fan that vents air to the outside or a continuous mechanical ventilation that meets certain criteria.
Extractor fans
Extractor fans installed after 1 July 2019 must meet the following:
- Kitchens – In any room with a cooktop, new fans or rangehoods must have a minimum diameter (including ducting) of 150mm or an exhaust capacity of at least 50 litres per second.
- Bathrooms – In any room with a shower or bath, new fans must have a minimum diameter (including ducting) of 120mm or an exhaust capacity of at least 25 litres per second.
Landlords should ask installers for the details of the fan diameters, ducting and flowrate in writing, so they can show they are compliant with the healthy homes ventilation standard.
Use our online tool to find out if you need to install new extractor fans in the kitchen and bathroom of your rental property.
If you have an existing fan
Fans put in before 1 July 2019 must ventilate to the outside of the house and be in good working order.
When they stop working, they must be repaired to be in good working order or replaced with fans which do meet all the requirements.
Continuous mechanical ventilation systems
The ventilation standard allows properties with certain continuous mechanical ventilation in kitchens and bathrooms to meet the standard.
Properties with certain continuous mechanical ventilation systems can meet the standard. This is an alternative to meeting the standard by having extractor fans.
If your home was built with a continuous mechanical ventilation system, to meet the standard it must:
- be designed to vent extracted air continuously from the property to the outdoors, and for a kitchen or bathroom, extracts the air directly from the room, and
- have been installed in the property or a tenancy building that first received building consent on or after 1 November 2019 and was part of that original building consent and continues to meet the requirements of the building consent.
If your home has been renovated and now includes a continuous mechanical ventilation system, to meet the standard, the system must:
- be designed to provide ventilation for multiple rooms and to continuously extract air to the outdoors, and
- extract air directly out of the kitchen and bathroom, with an exhaust capacity of at least 12 ℓ/s in the kitchen and 10 ℓ/s. in the bathroom. The actual flow rate may be varied (manually or automatically), in response to the demand for ventilation.
Recirculating systems (products like HRV and DVS systems), or fans that do not extract to the outdoors are not suitable to meet the ventilation standard.
Our guidance document has more specific information on the ventilation standard:
Exemptions to the ventilation standard
There are 2 specific exemptions for the ventilation standard. The information here is an overview.
- A room does not need to meet the requirements for openable windows and external doors if it was lawful when it was built or converted into a habitable space. If having fewer windows or doors was only lawful because the room met alternative ventilation requirements, then the room must still meet those alternative requirements to qualify for this exemption.
- This exemption applies to kitchens or bathrooms where it is not reasonably practicable to install an extractor fan. This exemption has a number of criteria which must all be met. We recommend landlords get professional advice and keep a copy of that advice to qualify for this exemption.
Examples of ventilation exemptions
- "The apartment does not have openable windows. However, the rooms in the apartment can be ventilated by mechanical ventilation, which was lawful at the time the apartment was built. The mechanical ventilation continues to meet the requirements of the building consent."
- "The rental property is on the third floor of a five floor building. A licensed electrician has advised that installing an extractor fan in the kitchen is not reasonably practicable. The room was lawful when built as it met the Building Code ventilation requirements for kitchens at the time by providing windows with a combined net-openable area of no less than 5% of the kitchen floor area. These openable windows are still present and functional."
- "The rental property is on the third floor of a five floor building. There is one kitchen and one bathroom. A licensed electrician has advised that installing extractor fans in both the kitchen and bathroom is not reasonably practicable. The rooms were lawful when built as they met the Building Code ventilation requirements for kitchens and bathrooms at the time by providing windows with a combined net-openable area of no less than 5% of the floor area of each respective room. These openable windows are still present and functional."
More information on the exemptions can be found in Subpart 4 of the Residential Tenancies (Healthy Homes Standards) Regulations 2019 Act.
These 2 exemptions are in addition to the general exemptions.
Last updated: 01 July 2025
