Features of a climate-friendly house
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1
It's the right fit
Only get the square metres you really need. Smaller homes are cheaper to build, easier to heat and use a lot less energy.
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2
The shape is simple
Rectangular shapes and multi-level homes have less outside wall and roof area so they’re easier and cheaper to keep warm. They typically use less building material than complex-shaped homes.
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3
It’s made from lower-carbon materials
Where the physical properties of steel and concrete aren’t required, use timber. Wood looks amazing and is less energy-intensive to produce.
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4
It’s 100% electric
Make the most of our 80% renewable electricity by plugging into electric heating, cooking and hot water systems.
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5
It’s EV ready
Even if you don’t have an electric vehicle (yet), pave the way by installing the wiring for an EV charging unit – it’s cheaper than doing it later.
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6
The lawns aren't perfect
Devote garden space to native trees and shrubs, flowering plants for the bees, veggie-growing and compost. Fossil-fuelled lawn mowers use energy and emit carbon.
Build for energy efficiency
The New Zealand Building Code provides a set of minimum mandatory requirements. Building beyond these can make your home warmer, more comfortable and energy efficient.
Design for the sun
- Orient your main living areas to face north so they get the most sun. Put service areas like the bathroom, toilet and garage on the cooler south-facing side.
- Well-designed roof overhangs allow direct sunlight to flood in over winter but provide shade in summer. They work best over north-facing windows. On east or west sides, where the sun is lower, deciduous trees and extendable shades or louvres work better.
Use your windows
- Windows let heat in – but also release heat to colder outside air. Choose larger windows for the sunny north side, smaller on the east and west sides, and smallest on the south side.
- Choose double-glazed panes and low-e glass.
- Place windows so air can flow through rooms for summer cooling.
Insulate to a really high standard
When you build or renovate, you have a fantastic opportunity to insulate your house to the max. Building code requirements are an absolute minimum – take the option to install a much higher standard.
- Walls – insulate the cavities as well as the roof space and under floors. Minimise plumbing and electrical services inside external walls as the cavities won’t be so well-insulated or airtight.
- Concrete floors on the ground – insulate underneath and around the perimeter.
- Attached garage – insulate between it and the rest of the house.
- External entrances – keep out cold draughts with a porch or hallway that can act as an air lock in the winter.
Use heat-absorbing materials
Solid materials that absorb heat during the day and release it when the temperature drops at night are known as thermal mass. Design them into rooms that capture the winter sun to enjoy free warmth in the evening. For example, if you have an insulated concrete floor slab you can paint, polish or tile areas where it gets direct sun.
Install a heat recovery ventilation system
All homes need ventilation to remove excess moisture and avoid damp and mould. The Building Code requires extractor fans in the kitchen and bathroom but for an energy efficiency boost, look at a heat recovery ventilation system. This pre-heats air coming into the house by capturing heat from air it pushes out of the house. You can get systems for a single room or the whole house.
Get extra support
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Smarter Homes
Up-to-date information and options for building smarter to make your home warmer, safer and drier. Includes guides, tools and case studies. Brought to you by the Ministry of Business, Innovation and Employment (MBIE) Building System Performance team. -
Homestar for home owners
Homestar is an independent rating tool that certifies the health, efficiency and sustainability of New Zealand homes. A Homestar rating of 6 or higher means the home will be easier and more cost effective to keep warm and healthy, and is more environmentally friendly than a home built to the Building Code.
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Level – the authority on sustainable building
Evidence-based advice to help you design and build homes with less impact on the environment, that are healthier, more comfortable, and have lower running costs. Developed for the construction industry by BRANZ Ltd, the independent research, testing, consulting and information company. -
LCAQuick Lifecycle Assessment Tool
A free tool from BRANZ to help architects, designers and structural engineers make sustainable design decisions. It evaluates the carbon footprint and other environmental impacts of a building design.
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Passive houses in New Zealand
Passive House is an international standard for buildings that only require tiny amounts of heating and cooling to be very comfortable all year round. There are certification options for new and retrofitted houses. -
Superhome Movement
A not-for-profit organisation raising standards so all new homes are healthier and more energy efficient, while also promoting environmental, economic, and socially sustainable practices.