Golden Bay house gets highest energy efficiency rating

A Golden Bay holiday home may be New Zealand's most energy efficient house, achieving nine out of ten stars under the Home Energy Rating Scheme - the highest rating awarded yet under the scheme.

The Golden Bay Hideaway's ‘Little Greenie' house in Wainui Bay is so efficient that its room heating and hot water bills are expected to cost less than $50 per year. Its energy efficient features include:

• Large double-glazed windows orientated towards the sun.
• Smart use of building material - concrete floor and adobe walls collect the sun's warmth on sunny days and release it overnight.
• Super insulated roof, walls and floor (more than double that required by the Building Code).
• Solar water heating.

The annual heating demand of the ‘Little Greenie' is about 85% lower than for an average new build house, and about 97% lower than for an uninsulated house.

The ‘Little Greenie' is the first home to receive a 9-star home energy rating under the government's Home Energy Rating Scheme (HERS). The scheme, which is voluntary, rates a home's energy performance and recommends improvements. Homes are awarded a rating from 0 to 10 stars and are given tailored, expert recommendations on how to improve energy efficiency.

Home energy ratings are an invaluable tool to assist New Zealanders in making informed decisions on energy efficient building design. A rating includes:

• How well the building's design, materials, construction and orientation enable it to maintain a comfortable indoor temperature.
• The efficiency of a home's two biggest energy users: the space heating system and the water heating system.

"The ‘Little Greenie' house is not a low-cost design, but it's not luxurious either. This shows that highly energy efficient home design is achievable and affordable, using products and techniques readily available in New Zealand. And it shows the value of home energy ratings in giving sound information and helping to maximise a home's energy efficiency," said Mike Underhill, EECA Chief Executive.

Most of New Zealand's housing stock is very inefficient when it comes to energy performance. New Zealand has a problem with cold and damp houses, and minimum indoor temperatures are often below the minimum of 18 to 20 degrees recommended by the World Health Organisation.

More information on the ‘Little Greenie' house