THE AGE: Concrete the energy-efficient floor of the future

Ben Schneiders
April 24, 2007

MORE new homes will be built with concrete slab floors rather than timber ones, the building industry predicts.

Timber floors have been exempt from meeting five-star energy efficiency standards since the introduction of the regulations in Victoria in 2005.

Houses with a concrete slab need less energy to heat and cool than those with a timber floor, which makes it harder for wood floor houses to reach the five-star standard. But the exemption will be phased out next week.

Building Commissioner Tony Arnel said the industry, which has lobbied against the changes, had had enough time to prepare.

A spokesman for Planning Minister Justin Madden said the timber concession would end on April 30. Energy savings would cut the costs to home owners in the long term, he said.

Environmentalists have welcomed the end of the timber exemption but the building industry says it will add to costs, hurt the industry and reduce consumer choice.

Caroline Lawrey, the HIA's executive director for Victoria, said about 20 per cent of new homes used timber floors, a reduction from the 25 per cent when five-star was introduced. The HIA wants the concession extended for at least 12 months until new software that calculates energy use is introduced.

Some builders estimated that 15 to 20 per cent of their designs would be affected, Ms Lawrey said.

Mr Arnel rejected the claims and expected no reduction in the use of timber floors. He said timber could be used on top of concrete slabs and five-star regulations allowed builders to reach the standard with measures such as double glazing and solar hot water systems.

Gippsland builder Bruce Langford-Jones said 100 of the 120 houses a year his company built used timber floors, the most suitable choice for a hilly area. He expected to be forced to use concrete slabs, which he said could add $10,000 to costs.

The five-star regulations do not measure the energy used to create building materials. Research suggests concrete may be less energy-efficient over the life of a home than timber because of the amount of energy used to create it, an argument endorsed by the HIA."

Original article