TOM MCNEILLY Consultant Architect

The Victorian government has regulated that new houses have an energy efficiency rating determined by computer simulation. Alternatively, ceiling, wall and floor elements must achieve R Values that require the inclusion of insulating materials. The regulations exempt full masonry cavity walls, but many advocate abandonment of that exemption. The rest of Australia is considering similar regulations.
The paper uses reputable thermal performance programs to examine comparative performance of hypothetical, houses in insulated and uninsulated, light and heavyweight versions. It concludes that, although insulation is well justified in lightweight walls, inclusion in brick houses brings little improvement and the present exemption is justified.
Australian and northern hemisphere climates are compared. Distinctive features of Australian climates indicate that Australian regulation of thermal performance should not be modelled on northern hemisphere practices.