Double Garage Size NZ: Dimensions, Costs & Consent Rules

If you’re planning a double garage in New Zealand, the first question isn’t just about size—it’s about consent. The country’s building regulations allow certain detached garages up to 30 square metres to be built without a building consent, which changes the options considerably.

Standard double garage size in NZ (external): 7.2m x 6m (43.2 m²) ·
Minimum internal dimensions for two cars: 5.5m wide x 5.5m deep (30.25 m²) ·
Building consent exemption limit (floor area): 30 m² (single-storey detached) ·
Average cost to build a double garage in NZ (2026): $40,000 – $70,000

Below is a quick reference of key facts about double garages in New Zealand.

What Size Garage Can I Build Without Consent in NZ?

The Building Act 2004 Schedule 1 allows certain small detached buildings to skip building consent. For a double garage, the key threshold is floor area.

The 30m² Rule Explained

• A single-storey detached building up to 30 m² floor area does not need building consent, per guidance from Building Performance (MBIE regulator).
• The building must be at least 1.5 m from any boundary unless the council says otherwise Building Performance (MBIE regulator).
• If the double garage exceeds 30 m², you must obtain building consent Building Performance (MBIE regulator).

Single-Storey Detached Buildings Exception

Garages that are attached to the house do not qualify for the 30 m² exemption. Only buildings that are structurally independent and detached can use this pathway. According to Refresh Renovations (NZ renovation guide), consent costs vary regionally and can reach NZ$10,000 in some councils.

The implication: staying within 30 m² not only saves consent fees but also cuts compliance time. If your planned double garage is 6 m x 6 m (36 m²), you’re over the threshold—so you’ll need to either reduce size or budget for consent.

What Is a Normal Size for a 2 Car Garage?

New Zealand’s typical double garage dimensions vary by provider, but a few common themes emerge.

Standard Internal Dimensions for a Double Garage in NZ

• A typical double garage from Versatile (garage supplier NZ) measures 6 m x 6 m externally, providing 36 m² of floor area.
• Refresh Renovations (NZ renovation guide) suggests 7 m x 6 m for a two-bay layout.
• Ideal Buildings (NZ building supplier) offers double garages up to 24 m long x 9 m wide for multi-use purposes.

Minimum Size for Two Cars

• Minimum internal dimensions for comfortable parking are 5.5 m wide and 5.5 m deep Refresh Renovations (NZ renovation guide).
• For larger vehicles like SUVs or utes, consider dimensions of 6 m x 6 m or bigger Plan7 Architect (garage sizing guide).
• A 20×20 ft (approx 6.1 m x 6.1 m) garage is generally sufficient for two cars, but check storage needs Eagle Carports (carport/garage guide).

The implication: careful dimensioning can save both space and cost, especially if you aim for the consent-exempt 30 m² limit.

How Much Would It Cost to Build a Double Garage in NZ?

Costs depend on size, materials, location, and whether you choose a prefabricated kit or a custom build.

Average Double Garage Cost in NZ (2026)

• Basic double garage: NZ$35,000 – NZ$45,000 Refresh Renovations (NZ renovation guide).
• Mid-range double garage: NZ$45,000 – NZ$65,000 Refresh Renovations (NZ renovation guide).
• High-end double garage: NZ$65,000+ Refresh Renovations (NZ renovation guide).
• Prefabricated garages from suppliers like Versatile (garage supplier NZ) may come in under $40,000 for a basic 6 m x 6 m model.

Cost Per Square Metre

Using the Refresh Renovations basic cost range ($35k–$45k) for a 36 m² double garage, the per‑square‑metre cost works out to roughly NZ$970–$1,250. This aligns with the industry rule of thumb of $800–$1,200 per m² for a basic build.

Adding insulation, power, floor coating, or a workshop can add 20–50% to the total. The catch: you might spend $70k+ but that could still be less than moving to a house with an existing garage.

Does a Garage Add Value to a House?

A well-built double garage can make a property more attractive to buyers, but the return on investment varies.

Value Addition Factors

• According to Sheds.co.nz (NZ garage retailer), a double garage is a great investment for your property and can add value to your home.
• In high-demand suburbs, the added curb appeal and covered parking can shorten the sale timeline.

Comparing Garage Types

• Attached garages often add more value than detached ones because of convenience Ideal Buildings (NZ building supplier).
• Double garages are generally more desirable than single and can command a premium in family-oriented neighbourhoods.

What this means: the value gain depends on your local market. In areas where off-street parking is scarce, a double garage can be a deal‑maker. In oversupplied markets, the cost may not be fully recouped.

Is It Cheaper to Build Up or Out in NZ?

When adding a garage, you have two choices: build outward at ground level, or build upward (e.g., a garage under a new storey).

Cost Comparison: New Storey vs Ground-Level Extension

• Building out (ground-level extension) is generally cheaper than adding an upper storey Refresh Renovations (NZ renovation guide).
• Building up requires stronger foundations, structural reinforcement, and often full building consent—costs that can double the budget.
• For a double garage, a ground-level detached structure is simplest and most cost-effective.

Structural Considerations for Garages

• Combining garage with living space above is more expensive but may add more value per square metre in high‑value suburbs.
• Detached garages avoid the complexity of tying into existing house foundations.

The trade-off: a ground-level garage saves money now but uses yard space. Building up preserves the yard but can escalate costs. For most NZ homeowners, a detached ground‑level double garage hitting the 30 m² consent exemption is the sweet spot.

Three common double garage sizes, one pattern: the larger you go, the further you move from the consent exemption, but the more usable space you gain.

Key specifications every double garage plan in NZ should meet.

How to Plan and Build a Double Garage in NZ

Follow these steps to avoid costly mistakes and stay compliant.

1. Determine Your Size and Setback – Measure your available space and check boundary distances. A 30 m² garage (e.g., 6m x 5m) keeps you consent‑exempt if it’s detached and single‑storey Building Performance (MBIE regulator).
2. Check Building Consent Exemption Eligibility – Confirm the garage will be detached, single‑storey, and ≤30 m². If yes, you may proceed without consent, but still need to comply with the NZ Building Code and council bylaws Building Performance (MBIE regulator).
3. Choose Between Custom Build and Prefab Kit – Custom builds offer flexibility but cost more per m². Prefabricated garages from Versatile (garage supplier NZ) or Ideal Buildings (NZ building supplier) provide fixed pricing and faster installation.
4. Get Quotes and Compare – Ask for itemised quotes from at least three builders or kit suppliers. The basic cost range from Refresh Renovations (NZ renovation guide) is a good reality check.
5. Apply for Consent if Needed – If your garage exceeds 30 m² or is attached, file a building consent application with your local council. Budget for council fees, engineering reports, and potential wait times of 6–12 weeks.

The pattern: careful planning on size and location can save thousands in consent fees and construction costs.

“The 2.31 m garage doorway did not meet the 2.4 m minimum specified in the relevant standard.”

— Building Performance Determination 2019‑044, MBIE (PDF)

“New garages can cost as little as NZ$30,000 and can exceed NZ$100,000 at the high end.”

— Refresh Renovations (NZ renovation guide)

“A double garage is a great investment for your property and can add value to your home.”

— Sheds.co.nz (NZ garage retailer)

For homeowners in New Zealand, the smartest double garage move is often clear: stay within 30 m², keep it detached and single‑storey, and you can skip consent while adding genuine property appeal. For those needing more space, budget for consent time and cost, but remember that every extra square metre needs to deliver real utility—because the bank won’t pay for unusable space. So homeowners should ensure every extra square metre delivers real utility, because banks won’t pay for unusable space.