Queenstown company Rilean Construction has achieved the Queenstown Lakes’ first six-star Homestar rating for an eco-friendly evolution series home.
The six star rating is at the “high performing” end of the Homestar rating scale and has been awarded to Graham and Cristina Robinson’s Speargrass Flat Rd home.
The four-bedroom 290sqm Speargrass Flats house was constructed by Rilean under its evolution series sustainable homes.
The home was completed in April and certification was recently carried out by an independent Homestar Assessor, Josie Cederman of GreenBeing, who checked all areas of the home for efficiencies in the areas of water, waste, materials, energy health and comfort, management and the site, with 10 being the highest rating achievable.
The home underwent a number of tests as part of the certification. In addition, Rilean carried out blower door testing and thermography tests to verify the air tightness and thermal performance of the house.
“Most homes in New Zealand would sit at around two to four stars at best, so a rating of six stars is a significant achievement, especially as the evolution principles were incorporated into this home after initial concepts had been drawn up. It’s a testament to the design and ethos already developed under our evolution series homes.”
Rilean Construction launched its evolution series of homes last year, reflecting its own commitment to this field and in response to increasing levels of interest and knowledge from home owners looking to construct green homes.
“We’re delighted to now have the independent Homestar rating on one of our evolution homes,” said Mr Moffatt. “New Zealanders are becoming more aware of the importance of living in homes that are safe, warm and dry as well as being efficient in their use of water and energy resources.
“This is the future, and this is how we hope to see things done in a natural and pristine environment like Queenstown.”
Homeowners Graham and Cristina Robinson have been living in the home since Easter and are glad to see the “hard work” put in by everyone recognised with a high rating.
“Our home has performed very well through some of the coldest snaps of winter, and we’re delighted with how warm and comfortable it is. We love living in it.”
The Robinsons’ home performed well in the category of materials as part of its assessment. Materials were responsibly sourced when possible and selected with consideration to their low toxic content.
“The house also performed well in categories like space heating, hot water and thermal efficiency,” said Mr Moffatt. “We built in a ‘vapour check membrane’ that reduces air leakage and therefore heat loss and also provides structural protection. “
The home’s high level of insulation is achieved through the use of 140mm thick blown cellulose insulation in the wall cavities and high-rating fibreglass batts in the ceiling. A well-insulated polystyrene concrete slab system then ensures the home achieves excellent levels of free passive solar heat gain.
Key to the home’s efficient running costs is its ventilation system that uses a passive heat exchanger to warm up incoming filtered air. The evolution series also uses a solar hot water system in all of the homes.
“It’s a complex job to combine all of these eco elements into the design and construction of a home, all with the ultimate objective of creating an enjoyable, healthier and comfortable home to live in,” said Mr Moffatt.
Homestar is an independent body that is a joint venture between BRANZ (owned and directed by New Zealand’s building and construction industry) and the New Zealand Green Building Council, developed to give a single accreditation rating to New Zealand residential homes.