Address climate change through better housing
OPINION: Warm, dry, healthy homes are better for the people they shelter. Theres fresh air and its easy to keep warm in winter (or cool, in summer), without using lots of greenhouse-gas emitting energy. Those homes are better for the environment too, because they can be built with far less embodied carbon (think less concrete and steel; more timber). We already have the knowledge and technology to build houses that use radically less energy to heat and cool - 90 per cent less. With climate change driving more, and more intense weather events, we need to plan for heatwaves as well as plunging winter temperatures. We can look across the ditch to see what happens when air-conditioning loads cause power consumption spikes during heatwaves. Its not just homes. Around the world, there are public and commercial buildings built to the Passive House standard that maintain comfortable indoor temperatures year-round with a fraction of the energy required by modern buildings in New Zealand. There are schools and kindergartens, fire stations, office and apartment blocks, shopping malls and hospitals. Building better new buildings and fixing those that already exist is an essential part of meeting New Zealands carbon emission targets. Its also one of the few pathways that is actually profitable. Its not difficult and it doesnt rely on fixes that doesnt yet exist (unlike cows that dont burp methane). READ MORE: * Real estate responsible for 40 per cent of global carbon dioxide emissions: Report * The New Zealand Green Building Council calls for new buildings to be rid of gas and coal * First Kiwi passive house: Seventh winter without heaters Heres a roadmap for how to use Government stimulus spending to create healthier, higher quality, more durable buildings. We need a blend of policy decisions, industry partnership, setting an example with public buildings, incentivising developers and investing in training. The first basic and essential step is fixing the Building Code. Government should commit to raising the minimum standards for new buildings in achievable steps over time, thereby clearly signalling to industry what they need to work towards. As part of this, simplify the heating performance metric so that buildings can be easily compared. Further, give councils the legislative power to require or incentivise buildings above Code minimums (which are typically seen as a performance target rather than the reality that they set the standard for the worst house you can legally build). Second, Government should commit to demonstrating what is possible by substantially raising the bar with new public buildings. This should especially apply to social housing, which, thanks to a small line in the Healthy Homes Standards, may be cheaper to build to a certified Passive House standard compared to the Code minimum. This is because fixed heating units, for example heat pumps, would not be required as houses would stay warm enough without them. In a multi-story apartment block, hundreds of heat pumps are a considerable expense. It is often cheaper to achieve higher performance levels in larger buildings, whether apartment or office blocks or other commercial or public buildings, compared to single-family homes. Thats possible because critical mass was reached in two areas. First, designers and developers can choose from readily available, high-performance building components at a range of price points. Second, those industry professionals have upskilled and know how to design, specify and construct high-quality, high-performance buildings that are a pleasure to learn, work, shop or live in. The Government can hasten those tipping points by investing in industry-led training programmes that improve the skills of architects and designers, quantity surveyors, engineers and builders; and encouraging local manufacturers to retool and expand, so they can produce world-class building components right here in New Zealand. Currently, many of the high-performance doors, windows, building wraps and heat recovery ventilation systems are imported. That adds delay, risk and cost to building projects and it unnecessary. We can do it ourselves. This roadmap has been proven. Brussels, capital of Belgium and the EU, until recently had the dubious distinction of some of the worst buildings in Europe. Its now world leading. Its done that by providing seed funding, involving industry and demonstrating the value and feasibility of high-performance buildings. Passive House got backed early on because of its commitment to modelling energy use design stage, using a software package called PHPP. Thats crucial, because it gives designers, contractors and owners certainty about what will be delivered. And if theres a performance gap, its cheap to fix at design stage, compared to on a building site or after its been built. The city of Brussels kicked this programme off but, over a period of years, the market made it their own and a lot of innovations came out of the private sector. Its worth noting too that the Brussels programme also required high design values, environmentally friendly materials, water efficiency and close to zero emissions. We have an opportunity to do this in New Zealand, particularly as the Government considers its infrastructure investment decisions accelerated by Covid-19. We can build back better. *Jason Quinn is a building scientist and designer of passive houses.