Wind zone map of Australia: what your wind rating means

Australia’s wind zone map splits the country into wind regions, named A to D, and the region a lot sits in is where its wind rating starts. The rating builders call a wind class, from N1 to N6 or C1 to C4, then comes from that region and the ground around the lot, and every shed, patio and carport is built to one.

To check a particular block, type its address into RapidSiteplan: it reads the lot and the rules that apply there and checks the structure you place against them, in minutes.

Is there a wind zone map of Australia?

Yes, though the wind loading standard behind it calls it the wind region map. Region A covers most of the country, from the inland to the southern coasts, and region B covers bands between that broad area and the cyclonic coast. The cyclonic regions, C and the most severe, D, run along the northern coast from Queensland across the Northern Territory to Western Australia, with region D on the north west coast. The post on finding your wind region covers reading it for one address.

Where can I see the wind region map for Australia?

In the standard itself, and in the building code that points to it. The lines are drawn at a national scale, so near the edge of a region a few streets can fall either side of a line, and the wind region check reads the region for an address instead.

How do wind ratings work in Australia?

Wind load is the governing force on light structures in Australia. Rather than run a full engineering calculation for every backyard, AS 4055 sorts houses and similar low-rise structures into classes, sitting on the design basis in AS/NZS 1170.2. The class comes from:

Wind region: where in the country you are. This is the big one, and it is what splits the non-cyclonic N classes from the cyclonic C classes
Terrain: suburban with houses all around, outer or acreage with scattered houses, or open country
Shielding: whether there are rows of buildings upwind, some, or nothing
Topography: flat ground through to a gentle rise, a hill, or near a crest

The last three are assessed at your property, which is why two lots in the same suburb, or your lot and the neighbour’s, can land on different classes.

Is there a wind classification table?

N1 to N6 covers non-cyclonic regions and C1 to C4 covers cyclonic ones, with the number rising as the wind load rises. The table that sets each class against its design wind speed is in AS 4055, and sites that fall outside what AS 4055 covers are designed to AS/NZS 1170.2 directly by an engineer. A higher class means heavier members, more fixings and larger footings, and it shows up directly in the price of the kit.

What wind rating does a shed need?

The rating of the site where it stands. A shed kit is engineered for a wind class or a region, and the supplier asks for the site’s rating before pricing the kit: too low and the certifier cannot sign it off, too high and you pay for a structure heavier than the site needs. The class belongs on the order, on the engineering and on the drawings the certifier assesses. On mapped bushfire land the same shed also picks up a bushfire attack level, which is a separate rating from wind.

What only your address can answer

the wind region the property sits in
the terrain around it, and how much shielding the neighbouring buildings give
the slope of the land, and whether the lot sits on a hill or near a crest
the class that follows, which the Wind Checker returns for a property from its address

RapidSiteplan reads your block from its address: the boundaries, the buildings already on it, the rules that apply there and any overlay or easement, and checks what you plan to build against them on a scaled site plan.

Search your address to start. Site plans and assessments in minutes.

Common questions

Is there a wind zone map of Australia? Yes. The wind loading standard maps Australia into wind regions named A to D, with the cyclonic regions along the northern coast, and the building code points to it. The region is only the start: the wind rating for one lot also depends on the terrain, the shielding and the slope around it, which a map of the country cannot show.

Where can I see the wind region map for Australia? In the wind loading standard and the building code that points to it. The lines are drawn at a national scale, so near the edge of a region it is easier to read the region for the address than to read it off the map.

How do wind ratings work in Australia? A house, shed or patio is built to a wind class: N1 to N6 in the non-cyclonic regions and C1 to C4 in the cyclonic ones, rising as the wind load rises. The class comes from the region and three things read at the property: the terrain, the shielding from nearby buildings and the slope.

Is there a wind classification table? Yes. The housing wind standard, AS 4055, sets the classes and the design wind speed behind each, on the basis of AS/NZS 1170.2. The class for one lot is read from its region, terrain, shielding and slope rather than from the table alone.

What wind rating does a shed need? The rating of the site where it stands. Shed kits are engineered for a wind class or a region, and the supplier needs the site’s rating before it prices the kit, because a higher rating means heavier frames, more fixings and bigger footings.