David Laing is waxing lyrical about thermal masses and cool cross-breezes, but he is not talking weather.
The Illawarra Property Council chief is proudly showing us around his Mangerton home which has an environmental footprint as light as a ballet shoe.
"It's my first build but the idea goes back 10 years ago when the seed was planted about living more sustainably," he recalls.
"I did a whole lot of research and realised houses were built out of the wrong materials and wrong design for the site.
"Brick veneer, for instance, is the worst material because the thermal mass is on the outside and robs the occupants of any temperature buffering."
Laing and wife Anita agreed on what they wanted and then enlisted the help of architect Thor Vaarsen to make it a reality.
"It's very different and in fact looks as if it's wearing a big hat, but everything about it from the positioning on the land, the materials used and the design gives us maximum thermal comfort, good ventilation and light with minimum use of fossil-fuelled energy," Laing says.
"During winter, for example, we used the heater for no more than 12 hours and that's only when the energy nazi - me - allowed it when the temperature fell below 15 degrees," he says with a grin.
Laing, a town planning consultant with Cardno, says his favourite room in the mocha-coloured cladded house is his office.
"Sometimes I just sit there and take in the view that looks out to 12.5-metre lap pool which is solar-heated in winter.
"The theatre room is also pretty good … that's where I chill out with a glass of scotch to watch my war movies.
"It's fully insulated with lightweight concrete floors and heaps of of DVDs."
Any unfinished projects?
"Yes, I've still to put a roof on my cabana but I've got the rattan and BlueScope Colorbond so I'm halfway there," says Laing.