Questions about Windloading.

So, I want to put up a new fence. And, I want it to be the best fence in the whole world. I want it to last for 5000 years, kinda like the Great Wall of China. I intend to build a wooden fence with galvanized fence posts 2 3/8" in diameter, with wooden 2x4 cross members, and wooden slats. And right now, I want to figure out the wind loading. The fence has a length of about 14’-0" on one side, and another 14’-0" on the other, and is shaped like the letter “L” and is about 5’-6" high

A 14’-0" x 5’-6" fence equates to about 7.1572 square meters

Remembering my physics class tells me that air has a density of 1.2252 kilograms per cubic meter

A wind traveling at 200 miles per hour is traveling at 89.4309 meters per second

7.1572 sq meters x 1.2252kg x 89.4309 = 784.2208 N of horizontal force
So, a 200mph wind would apply a 784.2208 N horizontal force to a 14’-0" section of fencing.

Is this how people do windloading?

You can figure the windloading but how will that help you? Do you know the strenths of various materials and fence design to apply that knowledge?

I say just overbuild that thing.

Sink the fence posts deep. The deeper the better. As for what goes between the fence posts not sure what you can do except to space the fence posts closer together for overall strength.

There is a method here:

http://wiki.contesting.com/index.php/Wind_load_calculations

which purports to be for the layman.

Well, this is not how structural engineers in the U.S. do windloading. We use the formulas in ASCE 7: Minimum Design Loads for Buildings and Other Structures. I believe a fence would fall under section 6.5.14, Design Wind Loads on Solid Freestanding Walls and Solid Signs.

Generally, design wind load is based on a number of factors such as geographical location, local topography, height, openings, slope (for roofs) and proximity to a corner.

Wooden fences don’t last 5,000 years. In your case, maybe five to ten years.

I am not listening to any nay-sayers.

Thanks for the wikipedia link, and the ASCE standard. I am going to apply these to the problem tomorrow.

It is 2:00am here…