Keeping it green

As the first subdivision in New Zealand to require homes to achieve a Very Good rating under the Green Home Scheme and a six-star Home Energy Rating, Ferndale ticks many of the boxes for energy-efficient design.

The measures introduced to the Ferndale show home are a good example of the principles supported by the Energy Efficiency and Conservation Authority (EECA).

In keeping with EECA recommendations, the L-shaped house is oriented to the north to maximise the heat from the sun in winter, while providing shade in summer. Smaller windows on the south side of the house help reduce heat loss. This side of the property has been utilised for services areas, including storage and recycling bins.

A gallery space on the northwest-facing side of the house connects the living area with the bedrooms. This circulation spine features concrete floors and slab walls, which use solar energy for passive heating. The concrete has a thermal mass that traps the sun's heat by day and gradually releases it at night. As the gallery is stepped, the heat rises to warm the bedrooms at the top.

A solid fuel fire in the main living area is supplemented by electric radiant panels in the ceiling of the bedrooms to provide an energy-efficient heating solution.

Thermal insulation in the Ferndale show home is higher than the minimum specified by the Building Code. As well as floor and ceiling insulation, all exterior walls have insulated 140mm-deep timber framing, rather than the standard 90mm, to minimise the impact of external temperature variations.

Similarly, the use of double-glazed low-e glass on windows helps maintain a comfortable living environment all year round.

Water heating, one of the biggest energy users in a home, has also been addressed. The house features a Chromagen solar water heating system designed to save approximately 70% of the hot water energy. Other environmentally responsible initiatives include rainwater harvesting, greywater recycling, well-designed natural ventilation, energy-efficient lighting, and the use of energy-efficient kitchen and laundry appliances.

For further details, visit the EECA website: www.energywise.govt.nz.

Story by: Trendsideas