In mid-2024, RNZ reported that Building and Construction Minister Chris Penk was considering rolling back insulation and glazing requirements introduced by the previous Labour government under the H1 clause of the Building Code. The upgraded standards — which required significantly higher insulation levels in new homes — came into full effect in 2023 after a phased implementation.
The standards save an estimated 40% on heating costs for a compliant new home. Their potential rollback has generated significant controversy.
What the Current H1 Standards Require
The 2023 H1 upgrade raised the minimum insulation requirements for ceilings, walls, floors, and windows in new residential construction across all New Zealand climate zones. The changes were the most significant update to building insulation requirements in decades, and brought New Zealand’s standards closer to those of comparable cold-climate countries.
Before the upgrade, NZ’s insulation standards were significantly lower than those of the UK, Canada, and the Nordic countries — despite having similar or more demanding heating requirements in the South Island and higher North Island altitudes. Government experts told Penk in advice released under the Official Information Act that the old standards were “significantly lower” than comparable countries and that the upgrades had overwhelming public support when consulted on.
The Industry’s Concern
Insulation manufacturers, energy efficiency advocates, and public health researchers were among those who responded critically to the prospect of a rollback. Their arguments centre on three issues:
- Energy costs: A home built to lower insulation standards will cost more to heat for its entire life — potentially 30 to 40 years. The upfront saving in construction cost is paid back many times over in higher energy bills.
- Health outcomes: Cold, damp housing is directly linked to respiratory illness, particularly in children. Building to a lower standard creates homes that will generate higher health costs.
- Industry disruption: The industry has already adapted to the new standards — manufacturers have tooled up, builders have learned the new requirements, and supply chains have adjusted. Rolling back would create its own disruption.
Where Things Stand
As of mid-2025, the H1 standards remain in force. Penk has indicated a preference for “flexibility” in how the requirements are met rather than a straightforward rollback of the performance levels. The outcome of the policy review is ongoing, and builders should continue to design and build to current H1 requirements while monitoring for any regulatory changes.