Promoting Building Techniques that Withstand Tornadoes and Hurricanes, 1927

“Building to Resist Cyclones and Hurricanes” by L. Kraemer, Construction Engineer, Southern Pine Association, in the October, 1927, issue of The Bureau Farmer.

Each year hurricanes, tornadoes and cyclones collect their toll, destroying buildings and sometimes whipping out whole villages. And after each one has passed we hear about the “freaks of the storm.” Here is a single building standing intact with only a few broken windows, while all those that were around it were destroyed. Here is one that was lifted off its foundation and set down 20 feet away but otherwise unharmed. Here is a small frame building without a scratch, while the brick school building across the street that everyone thought was so safe, is lying in ruins with great loss of life.

But are these really freaks of the storm? If they are, it is a strange coincidence that in each building that stood without damage we have found the same principles of construction, while in every building that was damaged we can trace the damage to the omission of one or more of the simple details of safe construction. The building that was moved from its foundation but was otherwise undamaged was built right except that it was not anchored to its foundation. The building that was unroofed had all the safety details built into it except that the builder forgot to anchor the roof. The beautiful brick school building that everyone thought was so safe would have been if the designer had put in cross walls to brace the sidewalls, or had built more piers that were tied together across the building. In no case was it a fault of the material that was used nor a “freak of the storm” that permitted the building to stand, but instead was entirely the way the chosen material was used.

Before we can fully appreciate why it is necessary to do certain things to make a building safe, we must first appreciate the limitations that apply to the chosen material. Lumber, like any other building material, has its limitations, but fortunately they are easily understood, so with a little thought given to construction methods almost anyone can build a frame building that will weather any storm it will ever be likely to be called upon to weather.

Safety in frame construction is based entirely upon the principle of a triangle. Perhaps we can understand this better by imagining four pieces of lumber nailed together so as to form a square. If we turn this square up on one corner and press on the opposite corner, we have no difficulty at all in making the square collapse. Now, if we put in a fifth piece, nailing it at two opposite corners, we find that no matter which way we put our weight on the square, we cannot cause it to collapse. This is because we have divided the square into two triangles by putting in the fifth piece form corner to corner. It is this simple principle carefully applied to building construction that prevents a building form losing its shape and gives it the structural strength to withstand high winds.

Examine the buildings on your farm at the first opportunity and, if you can see a number of triangles formed in the framing, you have little cause for alarm. If you see nothing but squares or oblongs, take warning now and put in enough braces to form triangles at every corner and in the roof, but first be sure the building stands straight and p0lumb so that you won’t tie it into a leaning position.

When you build that new building you are thinking of there are a number of details you will want to know so you can be sure of the safety of your building. Think of these often now, and then when you are actually building you will see the reason for every one.

After you have selected the site for the new building, consider the nature of the soil. Is it usually wet and soft or hard and dry? You may want to use a post foundation. If so, make an effort to get some creosoted posts and be sure not to cut into them below the ground line.