AS4055 resource
N and C wind classifications: what the rating means
Wind classifications such as N1, N2, N3, N4, C1 and C2 are used in residential construction to describe the wind classification for a nominated site. The rating helps the project team coordinate suitable building products and structural details.
Direct answer
If a supplier or certifier asks for an N or C wind rating, they are usually asking for the site wind classification that applies to the project. QuickWind provides an AS4055 certificate for suitable projects.
What N and C indicate
In broad terms, N classifications are commonly associated with non-cyclonic wind classifications and C classifications with cyclonic wind classifications. The exact classification depends on the nominated site and applicable assessment pathway.
Why the number matters
The number attached to the classification affects what wind-rated products or design details may be needed. Suppliers and project designers use the classification to coordinate items such as windows, doors, garage doors, roof trusses, cladding and tie-down requirements.
What a certificate does not do
A site wind classification certificate identifies the wind classification for the nominated site. It does not, by itself, design or certify each building element. Product selection and design checks remain separate project tasks.
How to get the rating
For suitable Class 1 and Class 10a projects in NSW, QLD, SA and WA, you can order QuickWind online. Submit the site address, centre the map pin on the project location and complete payment.