The Dunlop Hub in Wanaka is the country's first officially certified Passive House office building, a tantalising preview of the future of passive home design, where the temperature is just right all year round with clean airflow, near zero heating costs, and no weeping windows.
The building has a Passive House Plus certification, the highest possible rating, which means it's not only highly energy efficient but also generates energy onsite from renewable sources. The Dunlop Hub showcases the benefits of careful attention to detail using the internationally recognised PHPP certification system.The 500m2 building includes open-plan office space for up to 10 people, plus a large, fully-equipped workshop. The total building energy usage is around 9100kWh a year, and with solar panels generating approximately 10,850kWh annually, the building has power to spare.
"Everything from the design to the materials was meticulously selected for its environmental credentials," says Dunlop Builders managing director Bryce Dunlop.
"The end result is a fantastic warm, dry, and homely space that is a pleasure to work in."
Southern Lakes ITM worked closely with Dunlop Builders on the project. While it wasn't their first passive house build, it was their first one with a "focus on everything to do with sustainability," says Southern Lakes ITM's Paul Piebenga.
"The entire team at Dunlop Builders are incredibly passionate about this, which has enabled us to copy and implement some of these disciplines within our business."
"Their business has some great people with awesome skills with a clear passion for working with timber. The finishing that's been done is extraordinary. I think it's stunning what they've achieved, and quite rightly, they should be extremely proud of the finished result."
"The end result is a fantastic warm, dry, and homely space that is a pleasure to work in."
What is a certified passive home?
A well-designed certified passive home will use around 90% less energy to heat (or cool) than a standard home, while maintaining a consistent comfortable temperature and clean, filtered air-flow all year round. The certification process is based on an internationally recognised building energy modelling system that determines the overall energy performance of a building and the performance of its individual elements.
The optimum design is unique for each home; the modelling can accurately predict the energy needs of a building anywhere in the country as it is based on specific site conditions rather than the standard climate zones in the building code.
From a hands-on building point of view, the key elements of a certified passive house are:
> Air tight construction
> Thermal bridge-free design
> Heat recovery ventilation
> High performance insulation
> Superior insulated glazing systems
There are strict performance criteria for achieving a Certified Passive Home. For more information, check out passivehouse.nz/about/about-passive-house