New Building Code requirements bring biggest energy efficiency change in over a decade

Published: 29 November 2021

The latest changes to the Building Code will make new homes and buildings warmer, drier and healthier, with less impact on the climate.

The changes focus on increases to insulation requirements and introduce 6 new climate zones to reflect the specific weather experienced in different parts of New Zealand.

“These are the biggest energy efficiency changes to the Building Code in over a decade and will support the building and construction sector to help New Zealand reach its goal of net zero carbon emissions by 2050,” says Jenni Tipler, Manager of Building Performance and Engineering at the Ministry of Business, Innovation and Employment (MBIE).

“The new requirements will reduce the energy needed to heat homes by up to 40%, allowing people to heat their homes more easily and efficiently, which will lead to positive health impacts and increased energy savings for New Zealanders.

“One of the simplest and most cost effective ways to boost thermal performance is to increase roof insulation. That’s why we’ve decided to double the minimum amount of roof insulation required for new builds across the country.

“Windows represent the largest source of heat loss in new homes, so we are increasing the minimum insulation level for windows across the country, with a focus on targeted higher upgrades in colder climate zones.

“We recognise that regions across New Zealand have very different climates and the 6 new climate zones announced today mean buildings will need to be constructed to different insulation levels to reflect this.

“The new window insulation requirements in the warmest climate zones will see a 2 step approach with an interim increase in the next year and an additional increase in the following year. By the end of 2023, all parts of the country will have a similar minimum level of window insulation requirements.”

The update to the Building Code is being made following a consultation that received more submissions than the last 5 years of updates combined, reflecting the high level of public interest in improving energy efficiency.

“When we consulted on the proposed changes earlier this year, we received overwhelming support for the changes from all parts of the sector,” says Ms Tipler.

“Over 98% of responses supported increases over the status quo in the shortest time possible.

“We have engaged with industry stakeholders to ensure that the changes we are making are readily achievable across the country. There will be a 1 year transition period for the majority of the changes and a 2 step approach for the window insulation requirements which will allow the sector to prepare for the changes before they become mandatory for new builds.”

Further changes in this year’s update include introducing suitable daylight solutions and weathertightness testing for high density housing and the introduction of a verification method for the energy efficiency of Heating, Ventilation and Air Conditioning (HVAC) systems, making it easier to show compliance with the Building Code.

In addition to the annual Building Code update, MBIE is also publishing the first in a series of operating protocols which are being developed to provide increased transparency and certainty about the activities MBIE undertakes as stewards of the Building Code. Each protocol will provide information about rules and/or principles that will help guide MBIE’s work on the Building Code.

The subject of these protocols is the role of MBIE, as the regulator, in the upkeep and referencing of building and construction standards, including a ‘tier framework protocol’ to identify the standards most critical for contributing to the Building Code.

More information on the changes is available on the Building website.

2021 Building Code update(external link) —

MBIE media contact