How much does house extension cost in Dunedin?

In Dunedin, house extension typically costs between $2,250/m² and $4,950/m² in 2026, depending on spec and site. Dunedin runs a little below the national average, but hill suburbs add retaining and the colder H1 climate zone lifts the insulation spec.

How much does a house extension cost per square metre in NZ?

Most ground-floor extensions run $2,500–$4,500/m² in 2026. A typical 30m² room addition therefore costs roughly $90,000–$135,000 including connection and finishes, plus consent and design.

Why do small extensions cost more per square metre?

Fixed costs — consent, design, getting trades on site — don't shrink with the project. Spread over fewer square metres, the per-m² rate rises.

Cost guide · Dunedin

House Extension cost in Dunedin (2026)

Typical Dunedin range

$2,250/m² – $4,950/m²

Most Dunedin projects land around $2,700/m² – $3,600/m². Prices run near the national average.

Why Dunedin differs

Dunedin runs a little below the national average, but hill suburbs add retaining and the colder H1 climate zone lifts the insulation spec.

Usually included

Foundation & framing for the new space
Cladding & roof to match
Interior lining & finishes
Connection to the existing structure

Usually excluded

Reworking unaffected existing rooms
Major structural changes to the original house
Landscaping around the addition
Council consent fees

Usually needs a building consent

Most extensions need a building consent; check whether your site or zone also triggers resource consent. Read the consent rules →

What Dunedin City Council charges for a consent

≈$4,700 to $6,600 indicative payable up front

Alter Dwelling $100,000 to $500,000: 8 to 15 processing hours at $239/hr, checking and admin, 10 inspections at $244 each, plus CCC $244.

Indicative time-based estimate. Published hour ranges; further charges may apply. Officer time is charged at $239/hr residential processing, $244 per inspection.

Source: dunedin.govt.nz building fees and charges. Compare consent fees across 63 NZ councils →

See 152 Builders on the register in Dunedin

Questions to ask before you sign

How will the new section connect structurally to the existing house?
Is the consent included, and who lodges it?
What happens to the price if hidden issues are found in the existing wall?

Dunedin house extension: common questions

How much does a house extension cost per square metre in NZ?: Most ground-floor extensions run $2,500–$4,500/m² in 2026. A typical 30m² room addition therefore costs roughly $90,000–$135,000 including connection and finishes, plus consent and design.
Why do small extensions cost more per square metre?: Fixed costs — consent, design, getting trades on site — don't shrink with the project. Spread over fewer square metres, the per-m² rate rises.

Before you pay anyone, check who they are.

Check the company that quoted you: company status, registration and what's on the public record, from the official NZ sources.

Check a builder

Actually starting this build? Keep watch on your builder for the whole build →

Figures are 2026 estimates for guidance only, not a quote. Actual cost depends on your site, spec and the company you choose. Always get written quotes and check the company on the public record before you pay a deposit.