A major debate is looming over the quality and amount of insulation required in the roof, walls, floors and windows of new builds and small buildings. The country’s building regulator, the Ministry of Business, Innovation and Employment (MBIE), has released a discussion paper that proposes to raise insulation standards and the energy efficiency of new homes and buildings. The new rules would bump up the cost of building new dwellings by thousands of dollars depending on which of the three options is chosen, with the extra cost greatest in the coldest parts of the country.