The Sunbird House - Cairns

The house is a showcase site for sustainable tropical living. It is a Queensland Builder's
Association Energy Aware Home Award winner. The Sunbird is a privately funded demonstration house, recently completed in Cairns, Far North Queensland. The house, of semi-traditional construction,
presents options in technique and technology for sustainable housing for North Queensland.
Some key features include climatically appropriate passive design, extensive use of
sustainably harvested timbers, selection of further materials on the basis of low
embodied energy, a solar energy installation generating of power needs,
a solar hot water unit, on-site collection and storage of 70% of
domestic water needs, a composting toilet to reduce
wastewater and nutrient outputs and appropriate
native site revegetation.

A low energy house in the tropics looks very different from one in the southern States:
Oriented to catch the prevailing breezes. Down south it is most important to orient the house
to the north to get winter sun, however in the tropics it is more important to orient the house
so that all rooms can be ventilated, (although a sunny room in July is still very pleasant in Cairns).
A large expanse of (well-insulated) roof is needed to protects the house below from sun and rain.
In the tropics it is recommended to put an insulation blanket over the rafters rather than on the
ceiling. If you are upgrading then use batts on the ceiling. Roof ventilation should be improved
with a whirly bird or ridge vent. This sucks hot air out of the roof space reducing heat transfer
through the ceiling - they can also be used to assist breezes through the house with
ceiling vents. East and west walls should be insulated if exposed to the sun.
Roofs and walls exposed to the sun should be a light colour to reflect heat.

A light timber or steel framed structure will store less heat than a masonry one, and so
cool down quicker at night. If using heavy building materials ensure they are completely
shaded throughout the day. All windows shaded with generous overhangs, awnings or trees.
A verandah provides cool outdoor living areas and shades the rest of the house,
but be careful it doesn't make your home too dark in the stormy season.

Ventilation is the key to a cool house in the tropics - air movement is crucial for evaporation
from our bodies which provides the cooling effect. Sliding windows should be avoided and louvred
windows should be adopted. Casements angled to catch the breeze or awning windows. Windows
should be sheltered from heavy rain. If you have to close your windows to keep out the rain then
you will lose the breeze also. Awning windows and louvres tend to keep out rain better
than sliders and so are good for southern aspects.

Other energy efficient improvements you can make include gradually replacuing old light bulbs
with efficient compact fluorescent globes. 12 volt halogen lights are less efficient than fluorescent,
but still more efficient than incandescents. Install electric timers and movement sensors
for when you forget to switch things off. Check energy ratings before buying appliances.
Go to www.energyrating.gov.au

Make sure there is good natural light. It can get quite dark during the wet season. Add skylights
with Sun control to save on lighting bills - any skylight will add to heat load, the small round ones
are best to limit heat. Install a solar hot water service. Get a manual booster with a cut out switch
installed so you have better control over the electric booster switch. There are government
rebates for installing a solar hot water system. Install ceiling fans - these do slowly use
energy so don't leave them on all the time, but they are the most efficient artificial cooling
available. Don't buy evaporative coolers, these cannot work in the tropics due to the humidity.

Su Groome and James Maude of Studio Mango are the architects responsible for the Sunbird.
Check out the Studio Mango at: www.grehnbuilt.com/studio_mango.htm

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“Common sense design and a choice of construction techniques involving energy efficient materials
and systems,” is the credo of the designers behind homes such as these at Carindale Pines

The house represents a comfortable living environment that offers home-owners efficiently designed
'smart' buildings. The modular-designed split system Solahart panels blend neatly into the roofline
and can be colour coordinated with BHP Colorbond in 18 natural-looking shades. Solar hot water
can provide up to 80% of your home's hot water needs, supplemented by a power booster to
maintain temperature on those rare days when the sun isn't shining. An energy efficient home can
look like any other house, but will be more efficient, use less energy and be more comfortable
in all seasons. Power-saving, energy-rated appliances are used throughout and Grid Interactive
Photovoltaic Power Supply Systems are incorporated into home’s electricity system.

Houses with grid interactive solar power effectively use the mains grid as a battery, with electricity
retailers like Energex contracting to pay up to 28c for every kilowatt hour (kWh) that your home
generates in excess of what it uses. Bordered by a strip of blue gums and acacias, Carindale Pines
Estate is dotted with towering hoop pines, eucalypts, wattles, teatrees, laurels and silky
oaks - which give the mostly flat terrain the relaxed atmosphere of a country golf course. The
building "footprint" has been designed to produce minimal impact on existing
environment prior to commencement of development, so that wherever
possible homes are sited in naturally occurring clearings.

A combination of enlightened design and the use of insulation and ventilation to reduce the
need for air-conditioning, large rainwater tanks, solar powered water heating and
energy-saving appliances to reduce household energy consumption by up to 40%,
results in significant savings on electricity and water bills. Carefully north orientated in
order to maximize capacity for solar gain in winter, the house is designed to keep the hot
Sun out in summer. Constructed from steel frames attached by a patented bracket and batten
system to an innovative external wall cladding - called Rendaline- that doubles as insulation,
the house is cooled in summer and warmed in winter by natural processes of the Sun
and weather conditions, not from artificial energy sources. "Maximizing a home's capacity for
energy efficiency, the integration of large rainwater tanks and solar power into the design, doesn't
detract from a house's appeal, while greatly enhancing its functionality and saving on bills for
power and water consumption,” designer and owner Patrick Brodie.

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For more information on energy efficiency in Queensland:
Check the Environmental Protection Agency website: www.epa.qld.gov.au