Site Classification

The Australian Standard AS4055 sets out the requirements for wind classification for low rise buildings, which is the process of determining the wind loads that a building or structure is likely to experience. This standard provides guidance on how to classify wind regions based on the wind speeds and gust factors that are likely to occur in a specific location.

The wind classification process involves determining the basic wind speed for a specific Region and factoring in topography, terrain category and shielding factors. This wind speed is then used to determine the wind classification for the site, which for NSW ranges from classification N1 (the lowest wind classification for NSW) to wind classification N6 (the highest wind classification for NSW). Each wind zone corresponds to a specific design wind speed, which is the wind speed that the building or structure must be able to withstand.

The standard also provides guidance on the design of buildings and structures to resist wind loads, including the use of wind-resistant materials and construction methods. It’s important to follow the wind classification requirements of the standard, as wind loads can have a significant impact on the safety and stability of buildings and structures. Buildings and structures in wind N6 classification need to be designed to withstand the highest wind speed, which can be more costly than buildings in wind classification N1, but it is important for the safety of the people and the infrastructure.