May 7, 2020

Insulation Standard

Are your rentals up to the Insulation Standard?

Ceiling and underfloor insulation has been compulsory in all rental homes since 1 July 2019. The healthy homes Insulation Standard builds on the current regulations and some existing insulation will need to be topped up or replaced.

Insulation stops heat escaping from the house. In general, the better insulated a home is, the more it will retain heat. This means:

  • it will usually cost less to heat the property
  • the property will be drier
  • the property will be less prone to mould.

All private rentals must comply with the healthy homes insulation standard within 90 days of any new or renewed tenancy after 1 July 2021, with all private rentals complying by 1 July 2024. All boarding houses must comply by 1 July 2021. All houses rented by Kāinga Ora (formerly Housing New Zealand) and registered Community Housing Providers must comply by 1 July 2023.

What is the required level for insulation?

Insulation requirements are measured by R-value. R-value is a measure of resistance to heat flow. The higher the R-value, the better the insulation.

Minimum R-values vary across New Zealand. Check what zone your property is in using the map below.

Insulation Standard - map of climate zones

The R-value of new insulation is on the product packaging. For existing insulation, check in the ceiling or underfloor space as the R-value from the packaging may be stapled to a beam. You can also measure the thickness yourself or consult a professional insulation installer. Existing ceiling insulation that was installed before 1 July 2016 must be at least 120mm thick.

Ceiling insulation that is less than 120mm thick is acceptable if the landlord can prove:

  • the insulation’s R-value met the minimum R-values (2.9 or 3.3 depending on the climate zone) when it was installed, and
  • the insulation’s thickness has not degraded by more than 30% (compared to when it was installed).

Insulation must be installed in accordance with New Zealand Standard 4246:2016.

All existing insulation must still be in reasonable condition to meet the requirements. This means there should be no mould, dampness, damage or gaps.

Exemptions to the insulation standard

There are three specific insulation exemptions. The information here is an overview.

1. Access is impracticable or unsafe

Some areas of some homes may be unsafe or not reasonably practicable to access. This may be due to:

  • their design
  • limited access
  • potential for substantial damage
  • health and safety reasons.

There is an exemption to the Insulation Standard for parts of homes where a professional installer is unable to access and/or insulate until this becomes possible (for example when a property is re‑roofed).

2. Partial exemption for certain underfloor insulation

If the rental home has existing underfloor insulation that was installed when the home was built or converted. This insulation must still be in reasonable condition. Landlords must have a copy of any compliance documents that shows the home met the requirements of the time. For example:

  • code compliance certificate
  • certificate of acceptance
  • another relevant compliance document.

3. Ceilings and floors with other habitable spaces directly above or below

The third exemption applies to areas of ceilings or floors where there are other habitable spaces directly above or below. This might be another floor of the same property or another apartment. These areas do not require insulation to meet the healthy homes insulation standard.


Other Standards

Need help with understanding the Insulation Standard?

We have dedicated property managers and have taken on board the new legislative requirements seriously.  All properties we manage will be compliant with the Healthy Home Standards.

If you need help with meeting the standards, talk to our team today on (09) 527 3980 or email

Visit our services page to see more how we can help you with your rental properties.

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