Free tool

Build budget calculator

Most build budgets go wrong the same way: someone multiplies a floor area by a per-square-metre rate and calls it the cost. That rate covers the building and nothing else. This adds the lines it leaves out.

RegionFloor area (m²)

Building work$654,000

200m² × $3,270/m² — the Q1 2026 average for Auckland, from consent data. This is the only line we fill in for you, because it is the only one we have a sourced figure for.

Everything else

These start at zero on purpose. They vary too much by council and by section for a national average to mean anything, so we would rather you put in a real quote than trust a number we made up.

LandThe section price, or 0 if you already own it.Site worksEarthworks, retaining, drainage, driveway. A sloping site costs far more than a flat one — ask your builder for a site-specific figure.Council development contributionsCharged per new dwelling. Your territorial authority publishes its schedule; the figure varies a lot between councils.Consent and inspection feesBuilding consent, resource consent if you need one, and inspections during the build. Your council publishes its fee schedule.Service connectionsPower, water, wastewater, fibre. Rural sites can be many times an urban connection.Landscaping, fencing, driveway finishUsually outside the build contract, and usually needed before you move in.Contingency (10%)Applied to everything above. Most people who have built will tell you to keep at least 10%.

Where the building rate comes from

It is the average value owners put on the building work when they applied for consent, divided by the floor area, for Q1 2026. It excludes land. It is an average across everything from a modest townhouse to an architectural one-off, so treat it as a starting point rather than a quote for your house.

Source: Stats NZ building consent data, analysed by interest.co.nz · the tables · checked 2026-09-16. Cost by region →