This is Why Pole Barns Should be Engineered
A line of strong thunderstorms moved through North Central Florida Saturday March 23, prompting severe thunderstorm warnings and a tornado warning.
The photograph is of the remains of a pole barn, which is suspected to have been hit by a tornado. No other structures in the area were destroyed, however there were reports of severe hail damage to the siding and windows of one manufactured home.
Luckily the eight horses who were housed in this barn survived.
Of course I am not able to personally visit the site to examine the damage forensically, however I can make some observations, which leads me to suspect this particular destruction was as much due to poor design, as it was to having been hit by high winds. If it had been an engineered pole barn, my educated guess is the damage might have been been minimal, if not “fixable”.
Look first at the building columns – leaning every which way. They did not break off from the wind, but are in pretty much every direction other than being plumb. This tells me they did not have any concrete around the bases of the columns, which would have kept them upright.
The columns are notched on the outside – which is a sign there was once a truss carrier (a beam from column to column to support the trusses) in the notch. As no truss carriers are yet in place, the connection between the columns and the truss carriers was obviously inadequate to withstand the uplift forces.
Connections are always the weak link in any structure. Every once in a while, the History channel will show a segment on building failures – and it is nearly always the fault of under designed, or under sized connections.
While a properly engineered pole barn may not have survived the full onslaught of a direct hit from a tornado, the chances of damage being minimal would have been far greater had a registered design professional been involved, and his or her plans followed.
Don’t take unnecessary risks with valuable property and animals. Seat-of-the-pants design is rarely adequate.
