23 May 2024

Building standards stuck in the 1960s, industry told

5:24 am on 23 May 2024
The frame of a new house under construction, with a blue sky behind it (file)

Standards for new homes in New Zealand are based on temperatures between 1961 and 1990, when average annual temperatures were already much higher. File photo. Photo: 123RF

The building industry has been told that New Zealand's building code is designed for a climate that no longer exists.

A housing summit in Auckland on Wednesday heard that standards for new homes are based on temperatures between 1961 and 1990, when the average was 12.5 degrees Celsius.

Average annual temperatures are already 0.7 to 1.3 degrees hotter than that, and rising.

While the government seems open to making houses cheaper to keep cool in summer and warm in winter, there was no indication yesterday of whether the building code will be changed.

Opening the 2024 Housing Summit, Matthew Cutler-Welsh of the New Zealand Green Building Council said even Australia was ahead of New Zealand when it came to ensuring the airtightness, which - along with insulation and ventilation - helped make new homes cheaper to keep warm in winter and cool in summer.

Cutler-Welsh said it could cost as little as 0-0.5 percent more to build a more sustainable home, with much lower running costs over its life.

But he said the building code needed an upgrade, because standards were based on temperatures for the 30 years from 1961.

Aotearoa was being left behind, he said.

Last year 37,239 building consents were issued for new dwellings.

Savings and efficiency

The Green Building Council released a report last week saying New Zealand could save $19-39 billion by 2050, by bringing in new measures to make buildings more efficient, at very low cost to taxpayers.

The measures included requiring new buildings to measure and shrink their carbon emissions; giving buildings energy efficiency ratings, like the ones on fridges; and ending new gas connections to new homes, while subsidizing people to switch to electric heating.

Robert Pannell - the former manager of the UK's zero carbon hub, a UK government initiative to move towards zero carbon homes - told the summit his country had shown that making buildings better could be done without hitting building industry profits.

He said people living in the houses benefited hugely from lower energy bills.

The zero carbon hub initiative had slashed household energy bills in new homes over nine years, he said.

Pannell said New Zealand could do the same, if the government set ambitious targets.

The next step for the UK was stopping new homes connecting to gas, a fossil fuel, from 2025.

That would change how people lived and would require training tradespeople, and getting consumers on board, he said.

Pannell said as a result of the whole programme of UK changes, the average new, four-bedroom home would cost less than half as much to run in 2025 as it did in 2006.

In New Zealand, the status of the previous government's work to upgrade the building code under its Building for Climate Change programme is unclear.

That programme was designing changes to the Building Code and other initiatives, to make homes lower emissions, cheaper to run, and more resilient to natural disasters.

At the summit, Building and Housing Minister Chris Penk praised the programme, but left any discussion of details to the next speaker - Antonia Reid of the Ministry of Business, Innovation and Employment.

But those hoping for an update would have been disappointed, with Reid saying the programme's direction was still being discussed with the government and she could not announce anything.

Get the RNZ app

for ad-free news and current affairs