Passive housing in warm climates
Investigating the potential for passive house designs specifically aimed at warm climates.
Traditional buildings in Indonesia make use of ‘passive’ cooling techniques. Being well ventilated, raised off the ground, and with shady verandas, their design allows them to stay cool in a tropical climate without air conditioning. The classic timber ‘Queenslander’ house also follows a similar design.
Now architects and engineers from both countries are getting together to compare notes on such designs and materials in a collaborative project funded by the Australia Indonesia Centre. One of the biggest problems is incorporating these design features into high density urban areas. About a third of the energy of modern buildings is consumed in heating and cooling, says engineer Dr Glenn Platt, Director of CSIRO’s energy efficiency research and a co-leader of the project. Much of that energy could be saved, leading not only to lower energy bills, but also to climate benefits by reducing the use of carbon-intensive fuels.
People have been working for many years on house designs that don’t need much energy input to keep people comfortable, he says. “But almost all the work has been focused on the cold climates of Europe and North America. We and our Indonesian counterparts are now looking at the opportunities in this area for warm climates.”
It’s all about using lightweight materials in designs that allow buildings to be opened up to the cool tropical breezes in the mornings and late in the day, Glenn says.
The Indonesian end of the project is led by Mr Jatmika Suryabrata of the Department of Architecture and Planning Engineering at Gadjah Mada University in Yogyakarta. In Indonesia, housing construction in very high density urban areas is needed, he says. Much of this housing is high-rise and a huge amount of this sort of construction is planned in coming years.
“Cross-ventilation in these buildings is a challenge. So creating more porous building masses for low income vertical housing will be critical. And ceiling fans could significantly improve thermal comfort,” Jatmika says.
Shading and building orientation are also significant factors. But another really important aspect of passive cooling is how people live and work in buildings, Glenn says.
“Passive designs rely on people, for instance, to open windows and allow buildings to cool down in the evening. People would need to change their behaviour to take an active participation in the operation of their houses and workplaces.”
“We knew a lot about these things 100 years ago,” he says, “but seem to have lost the skills as energy became so cheap and accessible.”
The outcome of this initial project will be a report on the opportunities for a larger collaborative research program into building such energy efficiency into dwellings and offices in both countries. “One area where Australia could assist Indonesia,” Glenn says, “stems from our experience in framing regulations to encourage certain building design practices.”