Australia’s boost in defence spending to 2.4 per cent of GDP by 2034 will push out other projects competing for builders, workers and materials and pile further pressure on a construction sector already struggling to meet the country’s infrastructure demands, the country’s peak construction body says.

The projected lift in defence spending from the current 2.1 per cent of GDP to $100.4 billion by 2034 is already showing in government procurement, with up to $10 billion in new projects entering tender databases over the past six months, new industry figures show.