Federal
Emergency Management Agency
In response to the
Labor Day tornado that hit the Town of Ladysmith Wisconsin the government
provided aid in form of money and labor to help clean up after the disaster. One
of the agencies involved was the Federal Emergency Management Agency (FEMA).
Besides helping with the cleanup and allocating funds to help the town rebuild
another part of FEMA’s role at Ladysmith was to help the residence plan for
the future. They did this by surveying the damage and figuring out what didn’t
work with the buildings that where destroyed and what can be done to help
improve new buildings in the future.
One of the most common failures associated with
the destruction in Ladysmith was the inadequate building designs from previous
years. This is not to say that the buildings were constructed poorly. It means
that the building designs and materials at the time were not as good as they are
today. One of the most common failures to houses that were destroyed or
sustained heavy damage was the fact that they were not fastened securely enough
to the foundation and the joints which are the weakest points in a typical
building were not reinforced. This makes the building susceptible to uplifts and
strong wind forces. One of the ways that current builders have overcome this is
to build buildings with a continuous load path. This is a building that from the
base up is reinforced at the joints and the lower structures more adequately
support the upper structures making the building more solid. Some of the ways
that this can be done is through the use of metal fasteners, which can be used
to secure rafters to the main structure of the building better than with just
nails. In some buildings the structure was not secured very well to the
foundation and in the instance of the church, it was completely destroyed.
Buildings such as these should have had anchor bolts holding the frame of the
structure to the base. Many garages and small buildings were destroyed for much
same reasons that buildings were destroyed in that the structure was not secured
together and that the structure was not secured to the base.
Another area that FEMA found typical
destruction in was the roof coverings and over hangs. The weakest part of the
roof coverings tended to be in the outer edge and corners of the roof where wind
strength was the greatest and able to separate the shingles from the roof. The
shingles and sheathing needed to be adequately secured in order to prevent the
loss of either. The overhangs that were found destroyed where not well secured
to the building and many times the columns that supported it were nailed in
instead of being fastened. Even with adequate construction overhangs experience
tremendous pressure both upward and down ward in a tornado making them very
likely to sustain damage.
Some of the suggestions that FEMA offered when the
residents rebuilt were that they replace the roofs and not just over lay new
shingles on what maybe a damaged roof. Each of the shingles should be fastened
by at least six nails or screws and never staples. Many of the problems these
residents experienced in FEMA’s report should be fixed when rebuilding under
the current building codes Wisconsin has in place. Because of the lack of
substantial income for the majority of the residence and the number of older
buildings located in the city the amount of damage done is not surprising.
Although these recommendations by FEMA will greatly improve the strength of the
dwellings it will not guarantee against further destruction should another
tornado hit the city.
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