It isn’t until you’ve lived somewhere for at least 12 months that you begin to understand the strengths and weaknesses of your house.

In an area such as this, where Winters are cold and Summers are hot, it would be reasonable to expect that houses would be built of stone, mud, strawbale or brick.

Stone, especially, because there’s so much stone lying around the countryside and just down the road, in Castlemaine, there are deep quarries where various types of stone have been gouged from the earth for decades.

But no. Houses here are mostly built of weatherboard.

We were once told that termites are not a problem in this area because it’s too cold for them in Winter. Whether this is true or not I don’t know, but if there are termites anywhere around here, they’d have a field day on so many wooden structures.

Charming though they are, weatherboard houses might as well be constructed of cardboard when bushfires incinerate everything in their path.

I read an article in The Age, just after the bushfires in Kinglake, about a house that survived the fire while its owner-builder sheltered inside it. Of all the houses nearby, it alone was still standing in a landscape of charred trees and ruined buildings.

The house was of an aerated concrete block construction, with steel frames. The owner-builder had used aerated concrete blocks because they’re fire-resistant. They’re also easy for just one person to handle because they’re so light.

Weight for weight, aerated concrete has similar environmental impacts to regular concrete. Based on volume, however, these impacts can be up to a quarter or a fifth that of concrete. Aerated concrete also seems to have lower embodied energy per square metre than a concrete alternative.

The embodied energy content (or emergy) of a building material doesn’t depend on the occupants of the finished building. It’s the energy that’s incurred when the material, from which the building is constructed, is manufactured and transported.

Because aerated concrete blocks provide more effective insulation than conventional construction materials, they reduce the energy consumed by heating and cooling. Combined with the fact that aerated concrete lasts longer than most building materials the energy used in its production and transport can be reasonably justified.

Of course, there is another unconventional building material that can withstand intense fire, has even lower embedded energy levels than aerated concrete and which provides excellent insulation: strawbale.

But a trip to the tip beckons and I’ll have to leave that topic for another day.

Acknowledgement: Your Home Design Guide