Site Analysis

Understanding all the features of a site, using and protecting the best, and minimising the impact of the worst.

New Zealand climate and environmental zones

Climate should influence building form and location on site, material choices, window/door size and placement, and loading and bracing requirements.

Find out about:

  • climate zones for energy efficiency
  • wind, earthquake, corrosion and snow zones
  • specific design standards.

Climate zones for energy efficiency

New Zealand is divided into three zones, based on average temperature data, for NZ Building Code compliance document H1/AS1 Energy efficiency.

Zone boundaries are aligned with those of territorial authorities.

  • Zone 1: Northland, Auckland Franklin District and the Coromandel Peninsula
  • Zone 2: The North Island except the Central Plateau
  • Zone 3: The Central Plateau of the North Island and all of the South Island

Climate zones are used to determine the required thermal performance  (if using specific design) or minimum R-value requirements (if using the schedule or calculation method of NZS 4219) for new construction and renovation work.

Wind, earthquake, corrosion and snow zones

Under NZS 3604 Timber framed buildings, New Zealand is also divided into zones based on other environmental features including wind, earthquake, snow load and corrosion.

Wind regions and lee zone 
Wind regions and lee zone


Earthquake zones 
Earthquake zones


Snow zones 
Snow zones


Corrosion zones – North Island 
Corrosion zones – North Island


Corrosion zones – South Island 
Corrosion zones – South Island


Design standards

Design factor Map NZ standard Design for…
Bracing Wind zone NZS 3604:
Fig. 5.1		 Bracing requirements
  Earthquake zone NZS 3604:
Fig. 5.4		 Bracing requirements
Durability Corrosion zone NZS 3604:
Fig. 4.1		 Timber treatment levels
Claddings selection
Fastenings selection
Flashings selection
Weathertightness risk Wind zone NZS 3604:
Fig. 5.1		 Building envelope risk matrix

The zones given in NZS 3604 are general classifications only. Specific design can result in more economically designed structures.

  • AS/NZS 1170 Structural designs includes methods to determine wind, earthquake and snow effects for specific building sites using engineering first principles. A registered engineer is required to undertake design according to this standard.
  • NZS 3101 Concrete structures includes exposure classification maps to determine the steel reinforcing requirements of concrete construction. This standard identifies corrosion zones and also gives typical wind speeds and directions for New Zealand’s major cities.

More information