New Flexible Insulation Rules to Cut Costs for Designers, Builders, and Homeowners

Overly rigid insulation rules are being removed to ease costs for designers, builders and homeowners, Building and Construction Minister Chris Penk has announced.  I’ve heard clearly from the industry that the current one-size-fits-all approach to insulation requirements is needlessly driving-up costs.  The most prescriptive compliance pathway currently available for insulation – known as the Schedule Method – doesn’t allow for design trade-offs that can affect a home’s energy efficiency, like adjusting window size.  This has led to designers and homeowners having to over-insulate in certain areas to achieve Building Code compliance, offering little extra energy efficiency benefit at a significant cost.  To address this, the Ministry of Business, Innovation and Employment (MBIE) will remove the current Schedule Method in favour of more flexible alternatives.

Smarter online tools now let us take a balanced, whole-of-home approach to energy efficiency – enabling builders and designers to measure a home’s total heat loss instead of being locked into prescriptive requirements.  Using adaptable Calculation and Modelling Methods is shown to cut the cost of an average new build by up to $15,000.  The government will now work closely with the sector to ensure a smooth transition before the change takes effect.  The Schedule Method will be removed from the Building Code’s Acceptable Solutions and Verification Methods for Energy Efficiency by the end of the year, followed by a 12-month transition period to give the sector time to adjust.  I’ve also directed officials to explore designating the Far North as a separate climate zone under the Building Code, responding to calls from local leaders to ease insulation rules in the region.  The Far North District Council made a strong case in its energy-efficiency review submission, highlighting that the region’s warmer climate and need for affordable housing allow for a more tailored approach.  I’ve heard from the district council that building costs in the Far North are approaching $5,000 per square metre. They’re pushing for change to deliver more homes for locals at a reasonable price – an ambition I fully support.  In my view, recognising Northland’s unique climate with a separate zone is a sensible step that could lower costs and unlock much-needed housing supply.  MBIE will consult on any proposed changes to the region’s climate zone designation before final decisions are made, and I look forward to hearing feedback from the public.

This Government is committed to making commonsense changes and cutting construction red tape to make building easier and more affordable – putting more roofs over Kiwi heads, while ensuring those homes stay safe and dry for our families. Note to editors: In the context of thermal performance in buildings, insulation refers to materials that reduce heat transfer by acting as a barrier between two areas. This includes products like fibreglass, wool, and glazing.

Updated documents with the Schedule Method removed are expected to be published in November 2025. A 12-month transition period will run thereafter, so designers can continue using the old documents with the Schedule Method.

MBIE will support the sector with guidance on how to use the more flexible Calculation Method to demonstrate compliance with the Building Code.