Architect and writer Steve Mouzon calls the recent era of homebuilding the “thermostat age” because buildings depend on machines for heating and cooling, rather than good design.
“Originally, before the Thermostat Age, the places we built and buildings we built had no choice but to be green, otherwise people would freeze to death in the winter, die of heat strokes by summer, starve to death, or other really bad things would happen to them,” he said.
That’s the magic of vernacular architecture, creating buildings optimized for a specific place.
As part of its Sustainable Building Design Policy, adopted in 2011, the Cairns Regional Council has recently published a guide titled Cool Homes—Smart Design for the Tropics. The 31-page guide aims to help homeowners create a comfortable, efficient, and sustainable home that uses the vernacular design features appropriate for a tropical climate.
"A cool home is one that keeps out the heat and maximises the opportunities for cooling breezes, in so doing, reducing the demand for expensive air-conditioning,” Planning and Environment Committee chair Terry James said. "Designing and building a 'cool home' doesn't cost much more than a standard home,” James added, “but you'll save money on running costs in the long-term."
According to an Australian Bureau of Statistics report, the average home’s running costs have increased substantially in recent years.
“The cost of electricity, gas and other household fuels has risen in recent years. In the five years to the June quarter in 2012, the ABS Consumer Price Index (CPI) rose by 15% (from 157.5 to 180.4). During the same period, Australia’s retail electricity prices rose by 72%, while the price of gas and other household fuels rose by 45%,” the report states.
Key elements presented for passive design will be familiar to architects and many builders, but are invaluable to homeowners, as well. The guide is organized with a detailed checklist for design elements, and then elaborates on the ideas.
Some key design elements include:
● Roof insulation and ventilation.
● Generous eaves for shading; 800 millimetre minimum.
● Solar power and water.
● Louvre windows for 100 per cent opening to breezes.
● North-facing roof for solar panels.
● Vegetation on east and west walls.
● Minimum of two openings in each room for cross-ventilation.
● North-facing living area.
● Elevate buildings for cooling.
● Create livable outdoor rooms.
● Orientation for sun and breezes.
There’s more to it than comfort and energy savings, however. Extreme weather such as cyclones can take a heavy toll on homes, but appropriate design choices can be efficient and durable enough to endure a cyclone.
“Consider lightweight insulated walls that cool quickly,” the guide notes. “With current cyclone regulations, these homes are just as sturdy as concrete block, look great, and are available at the same cost. If using block construction shading is essential.”
In addition to publishing the Cool Homes Guide, the Cairns council has staged workshops to present the ideas in the Guide to residents. People from 50 businesses within the housing industry attended Cairns Regional Council's Cool Homes workshop in early August, addressing the challenges of designing for a tropical environment.
According to James, both the community and industry workshops were well received.
"There is an appetite for new ideas and new ways of thinking to challenge how things have traditionally been done," he said. "Some of the perceived barriers like affordability of sustainability features and lack of locally relevant information in the community and industry have been addressed in the Cool Homes Guide and workshops.
Council will hold the workshop again in September.
"Anyone thinking about building, buying or renovating a home should come along and find out how easy it is to design a home that suits our tropical climate," James said. "This workshop will help consumers better work with their architect, designer or builder to incorporate tropical design features in their home.”
The Cool Homes Guide is available at: www.cairns.qld.gov.au/buildings.