Contrary to myth, solid fencing does not provide the best wind protection. The force of the wind on the solid flat surface creates both pressure on the windward side and pressure differences on the leeward side, somewhat similar to the way an airfoil works.

To illustrate this, consider that snow fences are designed with porosity, which allows some of the wind to break through, but slows and diverts airflow. As a consequence of design, snow will tend to accumulate within a few feet in front of the fence as wind vortices are redirected.

When designing a wood fence for wind protection, stagger the boards 2 inches apart for every six inches of width. The ideal porosity for windbreak fences is 25-33%, and that gap will give a porosity of 25%. This provides protection that will extend eight to ten times the height of the fence. Another option is to slope the fence material, if you intend to use the fence as shelter for livestock.

For home and farm applications, consider building the fence in staggered sections, with each panel offset from adjacent ones by approximately one foot. This gap increases airflow redirection while reducing wind load on the panels. Varying the height of the panels will also help in this redirection. The intention, of course, is not to stop the wind, but to reduce and redirect it.

When installing a windbreak intended to act as a snow fence, do not install the fence right at the point where the snow will stop. Rather, move the fence back several yards, at least, so that the snow that is blocked off falls and accumulates before the path or cleared area you need. Remember that since wind protection (if properly installed) will create a buffer area eight to ten times the height of the fence, a four foot fence will provide a dead zone of up to 40 feet in front of the fence. .

Some permanent windbreaks are nothing more than a good line of trees or shrubs. However, solid rows of trees provide less protection than porous rows, so do not plant to create an impenetrable barrier. Instead, use staggered plantings, offset from each other.

Although it may seem counterintuitive, chain link fencing can also provide good wind breaks. Materials such as the mesh seen along the perimeter of golf driving ranges, plastic and resin mesh, and even chain link fencing provide a nominal measure of protection. To illustrate the effectiveness of a simple screen, open the window of your house on a cold and relatively still winter’s day and feel the coolness of the air blowing against the screen. Then reach your hand out and feel the difference. That screen has partially blocked convective heat transfer. It works similarly for the wind.

Windbreaks, then, are not so much windbreaks as they are wind speed bumps. Holding back the wind, to paraphrase the Jim Croce song about spitting in the wind or ripping the old Lone Ranger’s mask off, shouldn’t be a foolish attempt!