The exterior cladding is a combination of fibrous cement panels and western red cedar. Other passive houses have pergolas, louvres or shutters for shading in summer. Here, the large glass sliding doors are set back a little and protected by an overhang... : Passive progressive

The sunlit hall leads from the front door past a block wall to the open-plan kitchen and dining area. : Passive progressive

The airtightness of the home was verified with ''blower door'' tests, which involved fitting a large fan to a door and pressurising, then depressurising the building. The first test was carried out during the construction so any leaks could be located... : Passive progressive

John Crump plays on a bunk with son Micah (2). He and wife Jen wanted a healthy environment for their four boys to grow up in. ''We didn't go 'low spec' . . . '' Mr Crump says, ''But I wouldn't want people to think they can't build a passive house... : Passive progressive

A mechanical ventilation system, crucial when the house is so airtight, recovers heat from the stale air that is ventilated out of the building and transfers it to the fresh air coming in. An ''away'' mode reduces the air exchanges and power... : Passive progressive

The mechanical ventilation system draws stale, humid air from the bathrooms and kitchen. : Passive progressive

Built with structural insulated panels, Michael Sly and Jodie Lynes' Speargrass Flat home draws on the heat generated by its occupants and appliances. Mr Sly says his family has a better standard of living than before, for less money. Photos:... : Passive progressive

Built with structural insulated panels, Michael Sly and Jodie Lynes' Speargrass Flat home draws on the heat generated by its occupants and appliances. Mr Sly says his family has a better standard of living than before, for less money. Photos:... : Passive progressive