New Building Code – biggest response and update in a decade

The new Building Code receives the biggest response and energy changes in a decade.

After receiving its biggest response in 5 years the new Building Code update was released on the 29th of November.

The Ministry of Business, Innovation and Employment calls the change in Building Code the “biggest boost to energy efficiency rules in over a decade.” The change helps the building and construction sector support New Zealand to reach its goal of net-zero carbon emissions by 2050.

The 2021 update aims to make new homes and buildings more energy-efficient focusing on insulation requirements and climate zones.

The new Building Code introduces a verification method for the efficiency of Heating, Ventilation and Air Conditioning (HVAC). Additional changes include introducing suitable daylight solutions and weather tightness testing for high-density housing. Roof insulation requirements have doubled for new houses being built in New Zealand.

These adaptions make it easier to show compliance with the Building Code.

Six New Climate Zones

The new Building Code divides the country into six climate zones which reflect the weather in different parts of Aotearoa. “We recognise that regions across NZ have very different climates, and the six new climate zones announced today mean buildings will need to be constructed to different insulation levels to reflect this,” says Jenni Tipler the Ministry’s Manager of building performance and engineering.

New requirements will reduce the energy needed to heat homes by up to 40% according to the Ministry. This will lead to positive health impacts and increased energy savings for New Zealanders.


Nearly three-fifths of submitters favoured the most ambitious option presented by MBIE, which would see new commercial buildings required to use a quarter less energy for heating and cooling than existing standards mandate. In the end, most climate zones will see a reduction of between 20 and 23 percent.

Climate zone four, which covers the central North Island, the Wairarapa and the West Coast, will face the most stringent requirement of a 30 percent reduction in energy usage. The new standards also differ across building types. Schools, for example, are expected to reduce energy usage by only about 10 percent. Healthcare centres would generally become 34 to 36 percent more efficient, though those in climate zone four would see a 50 percent increase in efficiency. Offices would be required to use 22 to 34 percent less energy while shops would face a smaller reduction of just 18 to 25 percent.


Implementation / Roll Out

Most of the changes are expected to be implemented by the end of next year.

Requirements will be introduced over the next two years – the first year a transition period for the majority of the changes while the window insulation requirements will follow a two-step approach. Tipler says this allows the sector to prepare for the changes before they become mandatory for new builds.

“By the end of 2023, all parts of the country will have a similar minimum level of window insulation requirements,” Tipler says that they have engaged with industry stakeholders to ensure that the changes being asked are readily achievable across the country.

This year’s update received an overwhelming response reflecting the high level of public interest.  The update received more submissions than the last five years of updates combined.

According to the ministry, this feedback will help contribute to meaningful change and more certainty around how the building regulatory system will respond to climate change.

Requirements for walls have been left mostly unchanged because of timber supply issues. The report stated that more research is needed on new construction methods before wall rules can be changed. Design changes to wall framing under new rules also pose difficulties.

The ministry has promised to lay out protocols around how it would ensure that stronger rules are followed.

Further climate-related building regulations, including a cap on emissions from energy used by building occupants, are expected as part of MBIE’s Building for Climate Change programme next year.

Adapted from Radio New Zealand, Building Code changes to boost new houses’ energy efficiency, and New Building Code Requirements Bring Biggest Energy Efficiency Change In Over A Decade, Ministry of Business Innovation and Employment Press Release and Newsroom, Building Supply Shortage impedes climate targets, Marc Daalder

Affordable, build-ready Eco homes and low energy bills for life

Eco-home builders say that for the same amount as a conventional home you can have a house with near zero energy bills by dropping the size by 10 percent.

Homeowners are swapping out warm, dry, healthy cost-effective homes for an extra bedroom or bathroom.

Solutions lie within build-ready, energy-efficient home plans. eHaus is a nationwide housing company specialising in passive house design and construction. Recently eHaus released a collection of build-ready, energy-efficient house plans. The designs in the People’s Home Collection range from $560,000 to $650,000.

Whilst they are not certified Passive Houses, director Baden Brown says the three-bedroom houses have been energy modelled across all 18 climate zones in New Zealand – using the Passive House energy efficiency computer software (PHPP) as a performance base to maximise high performance.

“One of the biggest challenges when building a new home is budget and often as a trade-off things like energy efficiency and performance aren’t considered,” Brown says. “eHaus wants to bridge that gap.”

Brown confirms the plans will operate well above the eHaus Pacific standard. He says they will use 88 percent less heating energy than if the same plans were built to the current New Zealand building code.

With an airtight thermal envelope and air exchange system, the eHaus builds will maintain a constant minimum temperature of 20 degrees inside all year round requiring less heating and cooling.

The contemporary designs present spacious, open-plan living areas and soaring ceilings that follow raked rooflines. Sustainable materials, designs and construction are used to minimise waste.


eHouse is part of the Superhome Movement which recently held open homes throughout the country. Eco Built Homes is another Superhome builder in Christchurch offering the Affordabuilt range.

Director Kyle Byers was inspired from his own experience living with babies in old homes, paying $800 monthly for power in winter. He thought there must be a cheaper way to stay warm. He worked on the idea for years with a goal to design something warm, healthy and affordable to entry-level buyers.

“People are wanting to be in energy-efficient homes but can’t afford the big architectural homes with all the bells and whistles” Byers explains.

Byers says the Affordabuilt plans usually cost $330,000 to $350,000 for a three-bedroom home with one bathroom – and low energy bills for life. While they look like most other homes on the street it is what lies behind the walls, ceilings and underfloors that sets them and their power bills apart. Instead of airtight thermal envelope the Affordabuilt houses have thicker framing allowing for thicker insulation and in-slab radiant heating. Minimal thermal bridging is standard.

The $319,000 Canterbury home in the photo received winter power bills of just $160 a month, and $75 in summer. 

Adapted from Colleen Hawkes, Builders making high-performance eco-homes more affordable.

A check up from the House Doctor

Self-proclaimed House Doctor solutions could save homeowners thousands of dollars in energy and medical bills.

House Doctor

Nelson Lebo is an Eco-design advisor for the Palmerston North City Council. The House Doctor is frustrated with the state of New Zealand homes.

As an EDA Lebo diagnoses unwell buildings. He offers free advice on making existing homes warmer, healthier and more efficient through renovations and retrofits. “I’m a house detective, a house doctor prescribing solutions.”

With a PhD in science and sustainability education, the certified home-performance-advisor has diagnosed over 2000 homes and prescribed solutions aligning with family budget, lifestyle and type of house.

One client John Hornblow says “Nelson is so sensible and practical with so much technical knowledge and experience. His explanations were completely understandable.”

The better approach is not to amend existing homes but to design them more efficiently in the first place. Lebo says when he is invited to look over and review new house plans it is often too late for his recommendations – and by then too costly to be taken on board. He says that due to Covid uncertainties, the housing crisis, climate crisis, and rising costs, priorities don’t lie in designing efficient buildings. Instead they lie in simply getting them built as fast as possible. Lebo describes these factors as brewing a perfect storm against high-performance homes.


His plan?


The House Doctor believes he could help more wanting to assist homeowners for free with a tiny service cost to individual ratepayers.

Lebo observed people quickly adapting and using technology to communicate during Covid-19. He saw this as an opportunity to change his business model and reach a wider market. Lebo would like to advise people remotely making his service free to those who need it.

“Organisations such as a District Health Board, an Iwi, a Council, a Social Service pay for the membership and then all of their members or residents get free access to it.” Lebo explains his green, low-cost business model which could reap massive benefits.

Adapted from Janine Rankin, House doctor is frustrated people are building their houses wrong anCan’t sleep because of the heat? Try this clever fan trick


New Zealand’s first Zero-Cost Superhome is on the market!

Addington is home to New Zealand’s first Superhome – the first home in New Zealand designed and built to the highest possible Homestar rating – 10!

Insulation Heat Loss Diagram

The Homestar rating from the New Zealand Green Building Council takes into account energy use, ventilation, water, waste, health and comfort.

Only two other houses in the country have reached a 10 since this home’s completion in 2015. Most standard new builds in New Zealand would reach only a 3 or 4 rating.

This Superhome brings in Zero cost power bills. It is so energy efficient that it receives credits from the power company over the summer months.

Architectural designer Bob Burnett is selling the three-bedroom, two-bathroom home situated in Church Square Addington, Christchurch. His innovative house sits in place of an earthquake damaged cottage. According to Burnett (Superhome Movement co-founder) the home formed part of a vision for demonstrating healthier homes and more sustainable ideals for an energy efficient, low carbon future. For the last five years it was made available to the public as a demonstration home and is now on the market.

“The aim was to demonstrate that smarter designed and better built affordable, warm, comfortable healthy homes were easily achievable using better techniques and commonly available materials,” Bob says.

Insulation Heat Loss Diagram

Designed to provide the best possible living experience in a compact footprint, the 140sqm home fits a small 285sqm site – although Burnett says its design feels bigger. Environmentally certified natural materials are used to achieve the 10 Homestar rating, along with innovative technology not common in typical New Zealand homes.

Under the stairs a concealed storage cupboard contains a large hot water cylinder that acts as a heat sink, a solar PV inverter and batteries. An enlarged landing at the top of the stairs allows for a home office space and circulation to the three bedrooms and bathroom. The bottom three stairs have been turned into drawers for footlockers.

Insulation Heat Loss Diagram

Additionally the sustainable home features 18 solar panels, rainwater and grey water systems. Black tiles surrounding the perimeter assist with solar gain complete with a carport and electric vehicle charging outlet.

The ‘super-insulated’ home includes R10 ceilings, R4 walls and an R3.6 floor rating. Solar wall and heat exchange fresh air ventilation, and the concrete floor is fully insulated and heated with solar powered hot water. Recessed PVC durable windows with thermal bridging to reduce heat loss and mould growth.

Insulation Heat Loss Diagram

Listing agent Steven Ell from Harcourts Holmwood says that the home would be wonderful to live in with the combination of heating, insulation and ventilation making for a very comfortable environment.

Adapted from Joanna Davis, Want zero power bills in a suburb voted New Zealand’s best? Try this ‘Superhome’ for sale for the first time.

Got questions? Call us on 03 384 9001 or Request a FREE Consultation

From Rags to Riches – the Power of Insulation

Fed up with feeling cold and damp in their ageing farm house, property owners in Banks Peninsula wanted to downsize.

Insulation Heat Loss Diagram

Seeing potential in their neglected milking shed on the same property, the couple called in Walker Architecture designer Pete Hodge from Christchurch. Hodge came to take a look finding a structurally sound shed, solid concrete columns and beams. Together they decided to transform the milking shed into a classic yet glamorous home.

The determined couple were keen to do their own research and be involved throughout the process. “The clients were very driven to be informed,” Hodge explained of them understanding how the house would operate and breathe. 

The milking shed’s concrete structure allowed for absorption and storage of heat which met healthy home and energy efficient standards.

Peeled right back to its skeleton, rigid foam insulation was installed within the buildings’ walls, floor and ceiling. Windows and doors were positioned to minimise heat loss. Hodge explains that when the air temperature cools, the heat absorbed by the concrete is released back into the room where the insulation prevents it from escaping.

Insulation Heat Loss Diagram
Insulation Heat Loss Diagram

It was difficult for them to come to terms with not needing the existing log burner or space for storing wood due to the well-insulated design. They decided on a small fireplace purely for the cosy ambience.

The couple didn’t like the idea of a new townhouse. They wanted context and narrative which was achieved through the limited palette of materials and simple ‘L’ shape. The simplicity of the house and its original foundations keeps its connection to its rural environment and farm surroundings.

Adapted from Colleen Hawkes, Derelict milking shed converted into stunning eco farmhouse

Got questions? Call us on 03 384 9001 or Request a FREE Consultation

Be rental ready – insulation requirements have 1 July deadline – Auckland Council

By 1 July 2019, all landlords need to ensure their rental properties have ceiling and underfloor insulation according to the Residential Tenancies Act or risk penalties.

Key points to know about the ceiling and underfloor insulation standards:

  • Failing to meet these standards by 1 July 2019 could incur penalties of up to $4000
  • Landlords may face separate damages for every property that doesn’t comply
  • The government can act against landlords (in the Tenancy Tribunal and District Court) without initial complaints or alerts from tenants

Why is this being done?

The Residential Tenancies Act address inequalities and the health of the city’s more vulnerable citizens. On average, rental homes are twice as poor in quality as owner-occupied homes; and with one-third of New Zealand households – nearly 600,000 – renting, it’s a serious and wide-reaching issue.

Owners are responsible for managing the quality of homes; and while many landlords maintain and upgrade their properties, there are those who don’t, leaving tenants living in cold, damp homes which can lead to health issues, including respiratory and cardiovascular conditions.

With renting on the rise, poor housing standards are impacting an increasing number of people. The 2013 census showed that since 2001 there have been significant drops in homeownership for Aucklanders, especially among those in their thirties, forties, and fifties.

An added bonus

Insulating ceilings and floors also help to lower carbon emissions by requiring less heat to keep the house warm. Better-insulated houses are warmer, healthier and more energy efficient, contributing to Auckland’s low carbon goals to achieve better home energy efficiency.