Eco-Friendly Home
An example of a sustainable, healthy and environmentally friendly home.
Health and Safety Considerations
 Special attention has been given to creating a home and garden that are low on allergens which can cause asthma and allergy sufferers trouble.
A key element of the eco-friendly home is the incorporation of important health and safety features. Smoke and fire alarms
have been 'hardwired' into the home, avoiding the need for alarms run by batteries which can either run flat or be removed.
Fire blankets and extinguishers have been provided, electric cables made from 'low burn' materials were fitted and solvent-free,
flame retardant building materials were used. Low burn materials don't give off toxic fumes if they do ignite. (Fire-fighters have found
that in the case of a house fire, occupants are often harmed by toxic fumes rather than fire itself).
As detailed later in this magazine, the wiring has been 'laid out' to reduce electro-magnetic fields. This means it
has been styled in a radial formation (like a star) to avoid 'surrounding' the home's
occupants with electrical wires. Catches and locks on the eco-friendly home's windows and doors were also
chosen for their safety features. The window catches, provided by Interlock Group, are child safe meaning they don't
open too wide, preventing children from falling out and stopping anyone banging their head on an open window.
An additional safety feature is the fitting of safety glass to avoid the chance
of injuries if a window breaks. As the eco-friendly home is a single-storey, it's easily accessible for people in
wheelchairs and pushchairs.
Special attention has been given to creating a home and garden that are low on allergens which can cause asthma
and allergy sufferers trouble. An important consideration in creating an 'asthma-free home' is the building
materials used. Seventy per cent of people with asthma are affected by the allergen
produced by dust mites -particularly in humid climates such as Auckland. Consequently, the home was
designed with angled-skirting and without pelmets where dust can gather. Fitted carpets were also excluded to further
reduce the risk of dust gathering.
Eco-Gardening
 In the garden, gravel, paving and
mulching around plants have been used rather than bark which can also cause allergies.
Native plants from Henderson-based Eco Works Limited were chosen for the garden because they don't create a
pollen problem for allergy sufferers. These plants are pollinated by bees rather than the wind. (Wind-blown pollen
can be a major irritant to allergy sufferers).
Native plants were also planted to create a 'flow-on' affect between existing
bush at the rear of the property and new landscaping. Leafy rather than flowery plants were selected for the garden in a
bid to keep pollen levels down and avoid adverse side effects for allergy sufferers.
A mix of medium to tall trees such as titoki, kohekohe and mapou have been planted in the garden areas. It's hoped
that these berry-producing trees will eventually attract native birdlife back to
the area.
A small vegetable garden and fruit tree quarter also feature on the property.
A composting area has been set aside to encourage waste to be composted and used around the garden. Recycled
tree mulch can also be used around the garden to help reduce weeds, improve soil quality and preserve moisture over
summer months, reducing the need for watering.
Construction Materials
All the materials used to build the eco-friendly home were carefully analysed
to ensure they were durable and, where possible, from sustainable sources. Equally important was using building
materials devoid of chemicals such as polyvinyl chloride (PVG) which has been identified by some researchers as being
harmful to both human health and the environment.
Efficiently-produced materials
 Buildings use significant resources
and their construction has a considerable impact on the environment. A large amount of energy is consumed both
during the construction and maintenance periods. Energy is also used in
extracting, producing, maintaining and disposing of building materials.
Waste generated by the building and construction industries in Auckland alone
accounts for between 20 and 25 per cent of the city's waste. Yet much of this waste can be recycled or reused.
Consequently, the building specifications for the eco-friendly home included a section on how waste could be
minimised during construction. Wherever possible, timber offcuts were kept to a minimum and windows and doors were
situated in such a way to ensure efficient use of timber framing and gib plasterboard.
Contractors were also involved in a waste sorting programme called Project C&D (construction and demolition) which
is run by the Auckland Regional Council. Contractors were responsible for the disposal of waste materials from the
building site. These were sorted into bins and where possible, put into recycling schemes.
Apart from the research available from the BBE, the Auckland Asthma Society and Greenpeace were also both
consulted during the project to help identify building materials that are both healthy and take a minimal toll on the
environment.
The concept of 'embodied energy' was also a major consideration in the construction of the eco-friendly home.
This means those involved not only assessed the amount of energy used in the manufacture of the materials for the
home, but also the energy used to transport them.
As a result, locally-made materials from the Auckland region were given priority, followed by the North Island,
New Zealand as a whole, Australasia and then further afield.
Timber
 The timber selected for the eco-friendly home was checked to ensure
that wherever possible, it came from sustainable sources (New Zealand plantations or forest certified sources).
No endangered rainforest species or toxic timber were used in the construction of the home.
Chemical-Free Framing Timber
Radiata Pinex Laserframe was used for the eco-friendly home's framing and roof trusses. The Pinex Laserframe
timber is sold by Carters Henderson and produced by Carter Holt Harvey. The timber is kiln-dried, machine graded and
chemical-free. It undergoes a special drying process which sterilises and stabilises the timber, killing fungi and
insects. Borer are also not attracted to kiln-dried pine.
Pinex Laserframe timber meets New Zealand building code requirements and unlike offcuts of treated timbers, which
must be disposed of in toxic waste dumps, Pinex Laserframe offcuts can be used for firewood or disposed of
as ordinary waste.
Joinery, doors and outdoor framing
 Cedar was the initial preferred timber
for the eco-friendly home's joinery because of its performance qualities and aesthetic appeal. Herman Pacific was
given the job of supplying this material for the eco-friendly home.
Herman Pacific sources cedar from sustainably managed forests where trees naturally self-seed. The forests bio-diversity also is maintained by the
planting of two seedlings for every tree felled. Cedar was used for the eco-friendly
home's solid timber front door and matching double garage door.
One hundred per cent recyclable aluminium was used for all exterior window and door framing. The aluminium
proved to be very cost-effective which meant there was money left over for other areas of the home.
Kitchen cabinets were made from untreated pine framing, trimmed with eucalyptus fastfgata timber. The framing
for the outdoor pergola was made from eucalyptus saligna. All these woods are from New Zealand plantations.
Sustainably-grown and harvested eucalyptus (such as eucalyptus fastigata, which is also known as 'New
Zealand Ash') was also used for finishing work. This was used for skirting, door frames
and in the bathrooms and kitchen.
Outside the house, a pergola above the terrace and fascia for holding
spouting, was constructed from a red hardwood -eucalyptus saligna. Fencing was made from Australian Brushwood which
is also sustainably-harvested and regrown. The brushwood fencing is an excellent landscaping medium and
provides an ideal windbreak, filtering wind rather than blocking it. The filtering
effect also avoids any mould or rot forming, resulting in a maintenance free home. Brushwood fencing is estimated
to have a life in excess of 20 years.
Sustainably-grown New Zealand Pine was also used for flooring in the home.
Concrete and plaster
Building a home on a solid foundation
is critical. But perhaps what isn't always realised is how using the right foundation
can better heat and insulate homes.
The eco-friendly home was built on a 'double slab'. Firstly a polythene damp proof membrane was laid to insulate
pumice and concrete from the earth and keep it dry.
Next came an insulating slab of pumice. Pumice has air cavities and helps
insulate the top slab. It also stops any heat escaping into the ground. A concrete slab was poured on top of this.
The concrete floor slab provides a thermal mass store for the sun's energy. It has
minimum reinforcing steel mesh, reducing the amount of metal around the home which can contribute to detrimental effects
on health, with the metal acting as an antenna system for electro-magnetic fields.
Coloured concrete, grouted into a pattern, was used for the patio and back deck area. The concrete was laid by
Conlon Contractors Limited of Waitakere City and the colouring was supplied by Peter Fell Limited of Avondale. The patio
concrete itself was supplied by Firth.
The driveway and area behind the garage is made from coloured, exposed aggregate chips by McCallums Concrete
of Waitakere City.
Window glass and frames
 The glass used in the windows and
the type of window frames chosen help ensure the house is well insulated and ventilated (as prescribed by the Gib
Healthy Home 'Better' Solution). Vantage aluminium joinery was used for the window frames. It
incorporates small air vents which improves air circulation.
Glass is often a major source of heat loss, noise and safety problems.
Consequently, Hush Glass was used in the home's study to assist in soundproofing.
Hush Glass is made from two sheets of glass bonded together with a specially-formulated resin which dampens the
vibrations emitted from sound waves.
The Hush Glass used in the eco- friendly home is seven millimetres thick which reduces the sound you hear
through the window by 40 per cent. The glass also blocks 86 per cent of Ultra Violet light and transmits 66 per cent of
the visible light. It has very low solar heat gain, assisting the house to keep cool in
summer and indirectly warm in winter. It also helps improve insulation by adding
to energy savings for air-conditioning as well as lighting.
On the northern and sunniest side of the house, EverGreen tinted and toughened glass has been used. The tinted
glass absorbs more solar radiation than clear glass.
The bedroom windows are fitted with double-glazing and all windows throughout the home are made from
toughened glass.
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