The tables below provide maximum wind speeds for non-cyclonic and cyclonic regions. For cyclonic areas, the only suitable cladding is Superdek, Smartspan and Wavelok. Fences with no free ends, or with internal sections that are further than two panels from a free end, can be designed using the maximum wind speed for tapered ends. Corners or openings with solid gates are not classed as a free end. If you are unsure of your wind speed refer to the “Determining Wind Speed” section.

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Maximum wind speeds for a 900mm high fence or 1200mm with a Screen Top extension

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Profile	Style	3 Sheet Panel		3 Sheet Panel & 50 SHS Posts		2 Sheet Panels		2 Sheet Panel & 50 SHS Posts
		Tapered End	Square End	Tapered End	Square End	Tapered End	Square End	Tapered End	Square End
Superdek, CGI, Wavelock, Smartspan	Standard	W50	W50	W60	W55	W60	W60	W60	W60
	Screen top	W50	W41	W60	W41	W60	W55	W60	W60
CGI Mini	Standard	W41	W33	W41	W33	W60	W50	W60	W55
	Screen top	W41	W33	W41	W33	W60	W50	W60	W55

Internal panels, (panels that are not part of a free end) can be designed using the maximum wind speeds for tapered ends. For three sheet panels with SHS posts the post needs to be 1.6mm thick. For two sheet panels with SHS posts the post needs to be 3mm thick.

Footings

The sizes of post footings are dependant on the wind speed, soil type and the height of the fence. The following tables can be used to select the correct footing. Footings shall be founded in natural soil only. Concrete shall have a minimum 28 day characteristic strength of 20MPa (Grade 20). The top of the concrete should be shaped to direct water away from the posts. For the three footings adjacent to a free end and posts supporting a gate, the footing size will need to be increased in depth by 100mm. All posts are to be embedded at least 500mm into the footing.