Climate Change Minister: cheaper-than-expected snug, dry homes should become the norm
Climate Change Minister James Shaw wants to see a dramatic lift in the quality of new builds, so they require minimal energy to stay warm and dry in winter and cool in summer. Based on Kainga Oras experience building higher-quality social housing, the construction costs can be very little extra while there are numerous benefits from smaller energy bills to improved health and productivity, Shaw said. The average household produces 1.2 tonnes of carbon emissions every year through its electricity consumption more if it uses gas. Homes with smaller energy bills will lower the countrys greenhouse gas footprint. The ministers comments came during a green building event hosted by architects Warren & Mahoney. READ MORE: * Would you buy or rent a home with a G-grade energy rating? * Election 2020: Greens look to cut construction industry emissions with new plan * Our 'world-leading' proposal to count and cut building emissions In 2019, Kainga Ora pledged to build houses above the minimums set by the Building Code, choosing the NZ Green Building Councils rating tool and aiming for Homestar 6 (or good on the 10-point scale). Shaw said the extra costs to meet this standard for new social housing had been less than first expected. This comes as no surprise to me, but its been a lot cheaper to introduce that standard universally across all new builds than people were saying at first... Its not going to take much to then leap-frog to one of the highest possible standards, he added. We [the Government] are thinking about lifting that standard... perhaps something even as close as the Living Building standard or the Passive House standard, he told the event. Asked if these higher quality standards might extend beyond Kainga Ora projects, Shaw said: Theres no reason to suspect you couldnt do the same with all housing. Homebuilders wanting an energy-efficient and lower-carbon house today can choose to meet a number of voluntary standards, such as Homestar , Passive House and Zero Energy House . (For larger facilities, theres Green Star and Living Buildings .) Each puts different requirements on designers and builders and theres some debate about which produces the highest-quality construction. It is more expensive to build to any of these standards. A three-bedroom home that meets Homestar 6 costs around $7000 more compared to a home built to the current Building Code, according to 2018 estimates by the Green Building Council. Attaining Homestar 8 could add an extra $24,000 to $55,000 to the bill. The Zero Energy House design, which includes solar panels to ensure the home generates as much energy as it consumes, adds about $23,000 to construction costs. Proponents note the additional buildings costs are recouped through lower energy bills. However, Shaw said costs would come down if these high standards became the new minimum. High-quality buildings are all done on a voluntary basis, which means the materials and the designers are quite concentrated, and therefore the costs are high. But if you have a universal standard, then what happens is you get scale and so price comes down. Shaw said a plan to lift the construction standards for social housing and wider Government facilities further was in its early days. People living in cold, damp houses fall ill more often, requiring time off from work and school, he added. In some cases, because some of our houses are so bad, it just makes you crooker. Raising the standard of our houses will reduce health costs, improve productivity and boost childrens education, Shaw said. On top of the energy consumed, there are other, smaller contributors to a homes carbon footprint, including the materials, the construction process and any waste. Warren & Mahoneys Fiona Short said a low-carbon home has lower-energy needs, but is also smaller, uses space efficiently and is made of natural materials. People asking for low-carbon will massively shift what is provided. Green building proponents and the Government, through its Building for Climate Change work programme , are attempting to reduce all contributors to this whole-of-life carbon footprint. At the Warren and Mahoney event, Victoria University PhD student Emily Newmarch recommended architects ask about the carbon emissions associated with products and materials. She said the building industry needed to go on low-carbon diet, yet didnt know how to cut back. Effectively, for buildings and for products, theyre missing a nutrition label. Newmarch noted the recyclability of construction materials, such as steel, is important to their overall footprint, though the benefits would come in the distant future. Yet to limit global warming to 1.5 degrees Celsius, the world needed to cut carbon now. That might give a material such as timber an edge. Timing is really important. Stay on top of the latest climate news. The Forever Project's Olivia Wannan will keep you in the know each week. Sign up here .