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.
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