In response to rental sector feedback, the Government has agreed to amend the Healthy Homes Standards and its heating requirements for rental properties to reflect the higher thermal performance of new homes built to the 2008 building code requirements for insulation and glazing and apartments.

Changes to the heating standard

The Government has made changes to the heating standard for new homes built to the 2008 building code requirements for insulation and glazing and apartments, through amendments to the Residential Tenancies (Healthy Homes Standards) Regulations 2019 expected to come into effect in May 2022.

The heating assessment tool on the Tenancy Services website(external link) will be updated to reflect these changes once they become law.

The current heating assessment tool remains suitable for most of the rented housing stock in Aotearoa. Buildings which are not apartments and are not built to the 2008 building code requirements for insulation and glazing will still need to comply with the current healthy homes standards heating requirements.

The changes to the heating standard will generally enable smaller heating devices to be installed in new homes built to the 2008 building code requirements for insulation and glazing and apartments.

The updated formula for these building types will ensure tenants benefit from a living room which can be heated to 18ºC on the coldest day of the year by using the assumed external temperature assumptions for the location in Schedule 2 of the healthy homes standards. 

To assist in transitioning to these new arrangements, private landlords of new homes built to the 2008 building code requirements for insulation and glazing and apartments will benefit from a revised deadline to meet the heating standard. They will have to comply by 12 February 2023.

Government has also agreed to provide for more flexibility and cater for properties with innovative and energy-efficient technologies.  Developers can access an alternative route to complying with the heating standard.  Under this route, a specialist could certify that a rental home’s heating system will be able to heat the living to 18ºC on the coldest day of the year. In many developments a heating specialist will already be engaged for code compliance and/or design purposes.

Where qualifying heaters were installed prior to 1 July 2019, we will also change the electric heater ‘top up’ allowance from 1.5kW to 2.4kW. The trigger point to top up or replace existing heating installed before 1 July 2019 has also been revised to existing heaters that are at 80% of the required heating capacity, reduced from the current 90%. Once the heater needs to be replaced due to wear and tear it will need to meet the full requirement of the healthy homes heating standard.

Other planned changes include providing an exemption from meeting the heating standard for the small number of rental properties which use direct geothermal heating for which the heating capacity is not stated. 

What is changing?

Currently

Changes to

Heating formula assumption changes

 

a ventilation rate of 1.0 air change per hour

a ventilation rate of 0.5 air changes per hour

a constant pick up load (the energy initially required to heat the living room to the required temperature of 18ºC) of 40W/m²

a pick up load of 20 percent of the base heat requirement

heat loss of 50 percent from the living room to adjacent internal rooms.

heat loss of 25 percent from the living room to adjacent internal rooms.

Applies to: The change to the heating formula will only apply to:

  • Dwellings built to the 2008 building code requirements for insulation and glazing, including properties renovated throughout to these standards
  • Apartments of at least three storey and 6 units or more. 

All other types of building will continue to use the current heating formula. 

Provision of a different pathway for all dwellings to show compliance with the heating standard based on the policy intention

 

The required heating capacity must be calculated using the heating formula or the heating tool in every case.

As an alternative to the heating formula/tool a specialist will be able to certify that the heating standard is met based on criteria including that the heating device or system used will heat to and maintain the living room at 18 ºC on the coldest day of the year.

This pathway will be most economic for developers to use as in many cases they have already engaged a heating specialist.

Provision of a grace period

 

90 day compliance period after the commencement of a new or renewed tenancy.

For buildings subject to the new formula, the compliance date is 12 February 2023.

Increase the transitional ‘top up’ heating allowance

 

Allows a rental home with a required heating capacity of more than 2.4kW but with undersized qualifying heaters installed before 1 July 2019 to use electric heaters to ‘top up’ to the required heating capacity where the qualifying heaters are short of the required heating capacity by 1.5kW or less. 

Allows a rental home with a required heating capacity of more than 2.4kW but with undersized qualifying heaters installed before 1 July 2019 to use electric heaters to ‘top up’ to the required heating capacity where the qualifying heaters are short of the required heating capacity by 2.4kW or less.

 

Relax the tolerance so large living room heaters within 80 percent of the required heating capacity meet the heating standard. 

The heating standard is deemed to be met where large living room heaters each with a heating capacity of more than 2.4W, were installed prior to 1 July 2019, and do not meet the required heating capacity under the healthy homes standards but are within 90 percent of it.

Relaxes this tolerance so that large living room heaters within 80 percent of the required heating capacity will be deemed to meet the heating standard.

 

Allow some geothermal heating systems to satisfy the heating standard

 

Geothermal heating systems, which directly provide heat to the living room, and for which the heating capacity is not stated do not satisfy the requirements of the healthy homes heating standard. 

Allows geothermal heating systems, which directly provide heat to the living room, and for which the heating capacity is not stated, to satisfy the requirements of the healthy homes heating standard. 

 

Change to the ventilation standard

The healthy homes ventilation standard will also be amended to enable the use of continuous mechanical ventilation which extracts to the outdoors from kitchens and bathrooms, provided the system received building consent on or after 1 November 2019.

These systems are often used in well insulated, more modern homes but may not meet the current exhaust capacity or ducting diameter requirements in the healthy homes regulations. Because the system is running continuously it achieves a similar outcome to the ducting and exhaust capacity requirements.

What is changing?

Currently

Changes to

Allow continuous mechanical ventilation systems for dwellings built to the current building code to satisfy the standards

 

Continuous mechanical ventilation systems would typically not meet the requirements because they do not meet the minimum exhaust capacities or ducting diameters specified in the current Regulations.

 

Mechanical ventilation systems that continuously extract from kitchens and bathrooms will meet the Ventilation Standard where they are installed in dwellings that have first received building consent on or after 1 November 2019, provided the mechanical ventilation system was part of the original building consent and continues to meet the requirements of that building consent.

Clarification to the moisture ingress and drainage standard

A minor change to the moisture ingress and drainage standard for moisture barriers has been made. It clarifies that landlords are not required to install alternative moisture barriers where installation of a polythene barrier isn’t reasonably practical.

The changes are expected to come into force in May 2022.

What is changing?

Currently

Changes to

The standard has been clarified so that landlords are not required to install alternative moisture barriers where it is not reasonably practicable to install a polythene barrier.