Wind Pressures

The Basic Wind Speed, V_w is used for wind loading without ice build up.  In the ice loading case, the lower Gust Speed, V_i is used.  Both cases need to be checked to determine the effects on post and footing sizing.

The wind pressure tables below are based on ASCE 7 formulas, but rearranged to simplify the calculations and allow the use of tabular data.  To get the required pressures, round the wind speed values from the ASCE 7 Hazard Tool up to the nearest values on the tables.  Alternately, the values can be calculated directly using the formulas at the bottom of the page.

q_w is the wind pressure used for Wind forces

q_i is the wind pressure used for Wind on Ice forces

These wind pressures are raw values and must be adjusted by several factors on the following pages to determine the actual wind forces to the fence posts.

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