The honest answer is “it depends”, but not as much as you might think. Most single-storey extensions we build cost between $1,900 and $2,600 per square metre, finished.
What moves the price
- The ground: poor soil means deeper foundations
- Glass: big sliding doors and roof lights add up fast
- The kitchen: it can be a third of the total
- Access: a narrow side passage slows everything down
- Finishes: tiles, floors and fittings vary ten-fold
Decide the finishes before the quote, not during the build. Dana, chief estimator
Use our project cost estimator for a first figure, then book a free site visit for a fixed-price quote.


