Owners of many large buildings will soon be required to share energy ratings – but one group says minimum efficiency standards should’ve also been mandated to shrink the sector’s hidden emissions footprint.

Building and Construction Minister Megan Woods today outlined amendments to the Building Act – to be phased in from 2024 - that would mandate energy performance ratings on commercial, public, industrial, and large multi-level apartments.

The Government is also set to mandate waste minimisation plans that would need to be followed during construction.

Buildings make up nearly 10 per cent of New Zealand’s domestic emissions, through the energy they use directly, along with the associated emissions created over their lifespan.

It’s estimated the new measures could help slash some 12.6 megatonnes of CO2 equivalent before 2050 – equivalent to the carbon footprint of nearly 19,000 annual flights between Wellington and Auckland over that period.

“These proposals provide a clear signal that considering climate resilience, and the emissions impact of our buildings is a core responsibility of the sector,” Woods said.

“Energy performance ratings are already mandatory for some buildings in Australia and are popular with many building owners and the wider sector, because they help improve understanding of energy use while acting as an extra incentive for making better energy efficiency decisions.”

Along with cutting energy bills and other costs, Woods said a higher rating could also increase a property’s value or rentability.

“One study found an 8 per cent increase in asset value of energy performance rated buildings over those without ratings.”

Woods said the other new mandate could also have a positive impact, with one recent Auckland University of Technology study suggesting around $31,000 of building materials are wasted in every house build.

“These waste minimisation plan requirements support the Government’s work to transform the waste system with a new national waste strategy, as well as our investment in construction and demolition resource recovery infrastructure.”

The moves have been welcomed by the New Zealand Green Building Council, which has long called for more sustainability in the sector.

 “Energy performance ratings will massively incentivise building owners to consider how much energy they use,” the council’s chief executive, Andrew Eagles, said.

“As the saying goes - what gets measured gets managed.”

Eagles said the majority of buildings that would be standing in 2050 had already been built, and must perform at zero-carbon levels to help meet New Zealand’s climate obligations.

“We’ll never meet our 1.5C climate targets without seriously curbing our energy use and eliminating fossil fuels.”

Government departments were already required to obtain NABERSNZ certificates on buildings they leased, and many in the private sector were already doing it voluntarily.

Almost 100 New Zealand buildings and tenancies have a current NABERSNZ rating to benchmark their energy performance.

Together, they covered 860,000 square metres of office space, while consuming almost 670million kWh of electricity per year – enough to power over 83,000 homes.

“For most building owners it’s as simple as installing a metering system and taking stock,” Eagles said.

“There may be some upfront costs to get setup, but it’s going to help save a great deal on energy bills in the long run.”

The NABERS programme has been compulsory for many office buildings in Australia for years.

Since it was created two decades ago, it’s helped users save around NZD$1.5b in energy bills, and nine million tonnes of CO2 emissions.

Another major sector group, the Facilities Management Association of New Zealand, also applauded the amendments – but questioned whether they could have been more ambitious.

“For instance, it would be great if it included measures to ensure minimum standards of energy efficiency,” the association’s chief executive, Jo Duggan, said.

“We hope too that this announcement is intended to cover as many buildings as possible, rather than just large buildings over a certain size.

“Transparency alone may have been enough a decade ago, but the science on climate change is telling us we need to move much faster now, which is why mandatory minimums are needed.”

As Government buildings already had to meet energy efficiency standards, other buildings should too, she said.

“And including as many buildings as possible would help to tackle climate change further, and also encourage more building owners to employ the silver bullet of energy efficiency to drive down operational costs.”