Photo: RNZ / Samuel Rillstone
Minister of Energy Megan Woods has proposed changes to building regulations, including energy performance ratings and requiring builders to plan for waste.
She says the moves - proposed in a bill to amend the Building Act - will save on costs, and reduce emissions.
In a statement this morning, Woods said the energy rating requirements were popular in Australia because they promoted energy-efficient buildings, and cut costs for building users.
"They help improve understanding of energy use while acting as an extra incentive for making better energy efficiency decisions," she said.
"A higher rating could even 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."
Builders will also be required to produce plans for construction waste reduction.
Woods said this could help reduce costs as well, by reducing the over-ordering of materials and the volume of disposed waste.
Up to half of landfill waste was estimated to come from construction, and an Auckland University of Technology study had found about $31,000 of materials was wasted from every house built, she said.
The proposals were estimated to reduce greenhouse gas emissions by 12.6 Mt CO2-e by 2050, she said, equivalent to 19,000 plane trips between Wellington and Auckland.
Building make up nearly 9.4 percent of New Zealand's domestic emissions.
The bill's changes are expected to be implemented through regulations, which would be phased in from 2024 after public consultation.
In a statement, New Zealand Green Building Council chief executive Andrew Eagles welcomed the moves, saying it was "a huge moment for better, more sustainable buildings".
"The majority of buildings that will be standing in 2050 have already been built, and must perform at zero-carbon levels to help meet our climate obligations."
The Sustainable Business Council representing 34 percent of New Zealand's GDP, along with Engineering NZ and other industry-leading groups, had been pleading with the government for mandatory energy performance programmes, Eagles said.
Many in the private sector were already following them voluntarily, he said.
Voluntary waste minimisation efforts had also been able to divert up to 90 percent of a project's construction rubbish from landfill, "just through prioritising effective design and use of materials, reuse, and using building recycling services".
