Non Cyclonic Wind Speed Standards

The New Zealand Wind Classification system, commonly referred to as NZS 3604:2011, provides wind classifications for buildings in non-cyclonic (i.e., non-hurricane) areas in New Zealand. These classifications are based on the wind speeds and are categorized into N2, N3, and N4. The classifications represent different wind regions within the country. Here is a brief overview of each classification:

1. N2: This classification represents the lowest wind speed region in New Zealand. Buildings in this region are designed to withstand relatively mild wind speeds. N2 is typically associated with areas sheltered by hills or other natural features.
2. N3: N3 represents a higher wind speed region compared to N2. Buildings in this classification are designed to withstand moderate wind speeds. This classification covers a broader range of locations, including areas with moderate exposure to wind.
3. N4: N4 is the highest wind speed classification under the NZS 3604:2011 standard for non-cyclonic areas in New Zealand. It represents areas with the highest wind speeds and the greatest exposure to wind. Buildings in N4 regions are designed to withstand strong winds.

These classifications are used for building design and construction purposes, ensuring that structures are appropriately designed to withstand the wind loads in their specific regions. It’s essential to consult the most up-to-date local building codes and standards, as standards may be revised or updated over time, and local variations could apply. Additionally, consulting with a structural engineer or architect experienced in New Zealand’s specific requirements is crucial for ensuring the structural integrity of your building.