Cracks appear in brick’s reputation

THE double-brick dwelling has long been a favourite of homebuilders in Western Australia.

And with two of Australia’s largest brick manufacturers on Perth’s doorstep, brick has been a relatively cheap and readily available construction material.

However, the increasing labour and material costs attached to heavyweight construction has some builders looking beyond double brick to materials and construction methods that will yield greater economies of scale and ecological benefits.

Winner of the 2003 HIA WA GreenSmart Building of the Year award, Andrew Westbury, is one such builder. Mr Westbury believes the perception that double-brick construction is more energy efficient and cost efficient is misguided.

According to Mr Westbury, WA residents can save thousands of dollars when building their homes by adopting energy efficient and sustainable materials and practices.

He said a $100,000 saving was made on a two-storey house in Bayswater through the use of a structural design incorporating lightweight construction, good site orientation and window placement, minimal site impact, low material wastage and low water usage.

The final cost of the home was $104,000, but if it had been built with concrete and double brick it would have cost the owners approximately $192,000, Mr Westbury said.

“Heavyweight construction has a lot of associated costs, such as scaffolding, heavy lifting, access,” he said.

Mr Westbury said WA had a high proportion of homes made of double brick cavity walls and concrete slab flooring, which gave the illusion that these materials provided the best solutions for energy efficiency in the home.

“Every building material has its advantages, but when it is placed in the wrong spot there are no advantages,” he said.

Well-designed lightweight construction, which is the predominant construction method in other States, can save on labour, material and time loss costs, as well as reducing costs in heating and cooling, Mr Westbury said;

“To stay warm in winter and cool in summer, use well-insulated timber-framed walls. The only heat penetration will be directly through the windows,” he said.

“When windows are opened heat can be dispelled due to good cross ventilation. And in winter, lots of glass on the north side of a building will provide good solar penetration and keep you warm.”

Mr Westbury said thermal mass design was susceptible to common design faults, such as the dwelling facing 15 degrees east of north, or the omission of cavity brick wall insulation.

He said while his company would build in double brick if a client desired, lightweight construction allowed prefabrication of materials, greater flexibility of design, and reduced the construction time.

“There is a growing awareness that there are ecological and economic benefits in building with other methods and materials.”

Mr Westbury said the Efficiency Measures of the Building Code of Australia (BCA), adopted by WA in July 2003, and greater consumer interest in eco-friendly building and living solutions were behind the slowly increasing numbers of builders, designers and architects offering GreenSmart technologies and principles.