High performing, energy efficient homes, the only way forward.
Pictured: Camp Glenorchy, built to Net Zero Energy Building Certification.
The way we build houses in NZ is making us sick, costing us billions in health care and accelerating us to irreversible, ecological and environmental tipping points.
What is the problem?
The New Zealand building code is twenty years behind other OECD countries and the worst in the developed world. Ours is the lowest standard a house is legally allowed to be built, and as a result most homes in New Zealand do not meet World Health Organisation standards for internal air temperatures.
Take insulation for example. A new build in Dublin requires almost double the amount of insulation of one in Dunedin, despite the two cities having similar climates. Cold, damp and mouldy homes directly contribute to our high incidence of asthma and other respiratory illnesses. Respiratory illnesses are the cause for 1 in 10 hospitalisations and are our third leading cause of death, costing taxpayers over $7 billion per year. In July 2019 new healthy homes standards were introduced to make rental properties warmer, drier and healthier. The irony however is that homes built to code may be acceptable for owners to live in, but are no longer legal to rent out.
The way we build in New Zealand is also setting us back for reaching our greenhouse gas reduction targets. An average house in New Zealand produces 7 times the emissions required to meet our carbon targets under the Paris Agreement, with buildings accounting for 20% of New Zealand's total emissions. The Paris Agreement commits us to keeping global warming to under 2°C, but ideally under 1.5°C. We are currently on target for 3°C warming.
We need to turn the trajectory around. When we build, we lock in the emissions for the lifetime of the building. We need to construct energy efficient buildings, as close as possible to Passive House Standard.
Where do we want to be?
We need new buildings to be Net Zero Carbon by 2030 and to make sure operational carbon (energy used to run the house) in all new and existing buildings are Net Zero by 2050. The New Zealand Green Building Council has a road map for how we can achieve that. New standards for the building code will be released in November, but regulatory change will not transition us to healthy, carbon zero homes fast enough. Consumer demand is needed to drive change from the ground up to reduce our emissions and mainstream energy efficient buildings.
The pathway is clear. We need to build airtight homes, measure the performance of buildings, and ventilate them properly (such as with Mechanical Ventilation Heat Recovery Systems (MVHRS)). Passive House Standard is a rigorous, proven standard, with many countries already committed to it. Passive homes use 95% less energy than a house built to code, with studies showing that people living in energy efficient buildings avoid mental stress and increase their productivity via the avoidance of illness. Kainga Ora, New Zealand’s largest landlord is also leading the way for energy efficient buildings, and at scale.
Want to find out more?
Have a look at The Luggate Hall, QLDC's first passive council building.
Check out Passive House NZ and the NZ Superhome Movement.
For ideas and inspiration, read the UK’s Net Zero Carbon Tool Kit.
