House Insurance Rebuild Cost Calculator NZ — Sum Insured Checker

Most NZ house insurance is now sum-insured, so the number you choose is the most your insurer will pay to rebuild. This checker gives an indicative rebuild cost from floor area and build quality, including demolition, fees and cost inflation, so you can sanity-check your policy.

From your council property file, LIM or sale listing.

Indicative NZ 2026 rebuild rates incl. GST. Regional and site factors vary — Cordell's Sum Sure calculator is the insurer-recognised source.

Often $20,000–$50,000; more for hillside or asbestos.

Architect, engineer, council consents, project management.

Covers price rises between the policy start and a rebuild taking 12–24 months.

House build cost—
Garage & site works—
Demolition, fees & inflation—
Estimated sum insured—

General information only — not financial, tax or legal advice. Figures are estimates from the inputs you enter. Confirm with your adviser, accountant, lender or insurer.

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Prices exclude GST. Illustrative tools only — not legal, tax or financial advice.

Sum insured vs market value

Your sum insured has nothing to do with what the house would sell for. It's what it would cost to demolish the damaged house and build the same one again, including consents, professional fees and the price rises that happen during a long rebuild. Land isn't included — it doesn't burn down. After the Canterbury and Auckland floods, many owners found their sums insured were 20–40% short.

Where to get the official figure

Insurers generally accept the Cordell Sum Sure calculator (free, online) as the reference estimate, and some policies default to it. Use this page to understand the components and catch a policy that's drifted; use Cordell or a registered valuer for the number you put on the policy. Review it every renewal and after any renovation.

Assumptions and sources

Per-m² rates Indicative NZ 2026 residential rebuild rates incl. GST, derived from published QV/CoreLogic and building industry ranges; your region may differ by ±20%.
Fees & inflation Applied to the build + extras subtotal; demolition added as a lump sum.
Rounding Sum insured rounded up to the nearest $5,000.
Official source Cordell Sum Sure (sumsure.co.nz) — insurer-recognised; registered valuer for complex homes.

Last reviewed 6 September 2026. Rates and thresholds change — check the linked sources before relying on a figure.

Frequently asked questions

How much does it cost to rebuild a house in NZ per square metre?

Indicative 2026 rebuild costs run from roughly $2,500 per m² for a standard home to $4,000+ per m² for architecturally designed or high-spec houses, including GST but before demolition, site works, professional fees and inflation allowance. Regional labour and site access change these figures.

What is Cordell Sum Sure?

Cordell Sum Sure is a free online rebuild-cost calculator from CoreLogic that most NZ insurers recognise. It uses property data (size, materials, quality, location) to estimate a sum insured. Many insurers pre-fill your policy from it.

What happens if my sum insured is too low?

In a total loss you receive at most the sum insured, and you fund the shortfall yourself. Some policies include a small automatic uplift for inflation, but it rarely covers a large gap. Check the figure at every renewal.

Should the sum insured include GST?

Yes — rebuild costs for a private home are quoted including GST because you will pay GST on the rebuild. Make sure any per-m² rate you use is GST-inclusive.