Browse our home improvement features
Our Slow Ascent
New Zealanders are taking their time in catching up to the world standards in sustainable and efficient building, so what are we doing and where do we go from here?
Words by Michael Hooper
Robert Vale of Victoria University’s School of Architecture and his wife, Prof. Brenda Vale, are world-renowned authors on the subject of homes and sustainability. They say New Zealand used to be a leader in sustainable, efficient homes, but the world has outpaced us.
A cruise along Kiwi Drive reveals our lack of double glazing for a start. A two-year, NZ Business Council study reported last year that a million homes here are so poorly insulated that we’re paying nearly half a billion dollars a year to heat the street. Perhaps a legacy of this is our failure to rate the sustainability of our homes. Overseas research shows homes with performance ratings sell, and rent faster for higher prices than non-rated homes. Head of the World Green Building Council, Jane Henley, says New Zealand’s 1.6 million under-performing homes will become more visible as we deploy our own newly-developed rating system, Green Star NZ. “We have had no language to understand the performance of a home, let alone base purchasing decisions on a good, performing home,” she comments. “We don’t seem to have planned, integrated sustainable building programmes”, suggests Henley. “We have a fragmented industry that sells products, not solutions.” An example, says Robert Vale, is the uptake of energy-efficient heat pumps. While that has been positive, he says one recent advert incorrectly implied that heat pump installation lessens the need for draft proofing.
Our weatherboard homes define our local streetscapes. Our reliance on wood for building does give us points when comparing ourselves to overseas trends. It is renewable and our wooden dwellings seem remarkably durable. New Zealand’s Solid Wood industry group commissioned research at Lincoln and Canterbury Universities which demonstrated that solid wood has properties which keeps homes dry and warm. Wood showed 2.5 times as much thermal mass as concrete per kilo, says Dr Larry Bellamy, who undertook modelling that put solid wood homes in a similar thermal insulation category as standard timber frame houses – when constructed to the NZ building code. Solid wood ceilings and internal walls added even further to the heat retention benefits.
Beacon Pathway, a government and building industry research body, General Manager, Nick Collins, says the greatest environmental impact of a building comes not from its manufacture, but from its operation. In London, the recent completion of a 9-storey solid wood apartment building that took just nine weeks to erect, underscores the advantages. It will be 21 years before the CO2 emissions from the building’s operation equal the carbon ‘stored’ in the wooden structure. It’s a bit like a reverse mortgage, or carbon credits in the bank.
Retro-fitting various devices and insulation can improve energy use, but it is the environmentally better design, from the floor up, that will make the most strides in achieving more sustainable housing. A number of New Zealand companies go the extra mile, designing homes with built-in solar heating, rainwater harvesting, photovoltaic panels to generate electricity, composting sewage systems and grey water recycling.
Environmental Advisor to Prince Charles, Jonathon Porrit addressed The Princes’ Foundation for the Built Environment in the UK earlier this year. The theme was Building: A New Green Economy, and speeches included the role of locally available materials in sustainable building, as a way of boosting the recovery of regional economies. By 2016, all new homes in the UK must be built to have zero carbon impact. The Foundation estimates that building to the tough new standards will boost the economy by 2.6 billion pounds and support 90,000 jobs each year. Prince Charles himself emphasised the need for more responsible consumption and better environmental choices. “We in the industrialised world have increased our consumption of the Earth’s resources in the last thirty years to such an extent that, our collective demands on Nature’s capacity for renewal are being exceeded annually by some twenty-five per cent. On this basis, last year we had used up what we can safely take from Nature before the end of September."
If we are to rejoin the world’s progressive building movement and actively seek to live in sustainable buildings, Jane Henley’s view suggests the Kiwi psyche itself needs renovating. “We have to change the way New Zealanders think about their homes, to include performance not just location, kitchen and schools.”
Michael Hooper is Consultant Communications Advisor to Environmental Choice New Zealand.
Homestyle magazine celebrates real homes and affordable style
The team at Refresh Renovations will be happy to help you with all stages of your renovation project, including design, build and project management. Click here for a Refresh team member to contact you about a free no-obligation consultation to discuss options for renovating your home.