The Real Cost of Renovating in Australia (2026)

The number everyone gets wrong is the contingency

Renovations do not blow out on the parts you can see. They blow out on what the walls were hiding: waterproofing that has failed, wiring that no longer meets code, a drain that has to move. Industry reporting puts the hidden add-on at 10% to 25% of the budget, and a bathroom renovation ($22,500) is where it bites hardest because it is wet, old and small.

Price the job, then add a quarter again before you commit. The owners who do not are the ones whose $40,000 bathroom becomes $55,000 halfway through.

Room by room, what it costs

The HIA puts the average bathroom at $26,747, up sharply from $21,484 in 2021. A bathroom renovation ($22,500) and a kitchen renovation ($32,500) are the two most-renovated rooms and the two most prone to overrun. An ensuite renovation ($26,000) or ensuite ($20,500) and a laundry renovation ($8,000) round out the wet-area jobs where the plumbing drives the price.

When a renovation becomes a rebuild

There is a point where extending beats renovating. A home extension ($165,000) buys floor area; a second storey addition ($390,000) or house raising ($92,500) buys a whole level; and a full house renovation ($380,000) can approach the cost of knocking down and starting again. Knowing where that line sits stops you spending rebuild money on a renovation outcome.

Where the savings are

Do not move the plumbing or the walls: keeping the kitchen sink and the bathroom drains where they are saves more than any finish choice. Spend on the finishes people touch and see, not on the footprint. And get the soil and structural checks done before you sign, so the big unknowns become line items instead of surprises.