Consumer interest in sustainable building has been a growing trend in New Zealand during the past few years, and builders have responded to the demand by changing their building practices and the products they use.
In recognition of this, the Registered Master Builders House of the Year competition, in association with PlaceMakers, added the Sustainable Building Awards to the competition in 2008 to reward new approaches to building and renovating homes.
One year on, competition judge Bill Irvine says builders are becoming more and more aware of just what sustainable building really is, and are working hard to prove it.
“The standard of sustainable building in this competition has lifted dramatically over last year. There has been an increase in quality across all four covenants of sustainability — air, water, energy and waste,” Mr Irvine says.
“This ranges from builders using low Volatile Organic Compound (VOC) paint, to a wide variety of areas in energy efficiency.”
Some of the most notable properties in this year’s competition have been developed from what Mr Irvine describes as a cross-functional team effort.
“The hard part is ensuring the design team, the builder, owner and architect are all on the same page. It’s important that they all understand what makes a truly sustainable home, and that the owner continually maintains the sustainable elements after the job is done,” Mr Irvine says.
Standards are not only increasing within the competition, but also across the New Zealand construction industry, according to BRANZ sustainable built environment manager Lynda Amitrano.
She believes there are a number of elements that assist with the development of sustainable and energy-efficient building.
“Factors that will continue to support industry developments include greater social expectations around our environment, more use of passive design, a better understanding of how to achieve the best out of sustainable technologies and the use of ratings tools to increase awareness and promote sustainability,” Ms Amitrano says.
“There is also a much greater awareness among builders of the importance of how the details of construction impact the overall sustainability of the building, and the key area at the moment is energy efficiency.”
In judging the House of the Year sustainable entries, Mr Irvine also cites advances in the types of materials and products builders are using.
“There is a huge range of different products which will improve a home’s sustainability.
“Some of the most innovative developments have been in hot water systems, from the type of piping all the way to the cylinder and the features that supply water to it,” Mr Irvine says.
The future for sustainable building looks bright, thanks to an increasing awareness among builders and consumers of the benefits of sustainable building and recent changes to the Building Code, such as most new homes being required to have double glazing.
Ms Amitrano believes there are still a number of things builders can be doing to take these developments to the next level.
“An area where the builder has a large impact on sustainability is in managing construction and on-site waste to minimise the amount going to landfill.
“It’s up to the builders and subcontractors to ensure the benefits of sustainable design options are maximised during the build.
“The designer may choose a high level of insulation in the design to improve the energy efficiency of the home, but in order to make the most of this decision the builder or insulation installer must ensure the right product is used and installed correctly.
“There must be complete coverage within the cavities — no gaps or missing sections — and the insulation product must not be crushed or squashed, Ms Amitrano says.
“Similarly, the installation of a solar hot water cylinder must be done accurately to ensure it performs to its maximum potential.
“This includes the angle and orientation of the solar panel, the pipe work and insulation of pipes and controllers.”
Ms Amitrano and Mr Irvine have an optimistic attitude about the future of sustainable building, and believe the industry has made some promising advancements.
“In five years’ time it would great if all buildings were developed with long-term performance and costs in mind, not with a here and now philosophy,” Ms Amitrano says.