Storm Damage to Roof of Religious Facility

portrait photo of Charles

Charles E. Whitley, P.E.

The Assignment:

EDT was asked to determine the scope of storm-related damage to a religious facility.

EDT Analysis and Findings:

After a series of tornadoes passed through a southeastern state, a religious facility claimed in excess of five million dollars of storm damage to their property.  A contractor representing the interest of the facility provided engineering reports documenting storm-related damage to the roofing on all buildings at the facility, and structural damage to multiple buildings. 

The facility consisted of nine separate structures, varying from one story, steel framed storage buildings to multi-story, steel and masonry structures.  A portion of the roofs were flat and were roofed with flexible membranes, while others were steep sloped and were roofed with dimensional shingles.  The engineering reports provided by the contractor representing the facility documented wind damage to the roofing and water intrusion resulting from the wind damage. 

EDT began the assessment by obtaining and reviewing the construction drawings for the facility, along with numerous other documents related to the original construction.  For the inspection of the steeply sloped roofs, EDT employed a local roofing contractor to access the roofs and install anchors along the ridges.  Ropes were then attached to the anchors such that the EDT engineers could be safely tied off for inspections of the slopes.  Each slope of the buildings roofed with dimensional shingles was then inspected for storm-related damage and any other conditions that would allow water intrusion into the facility.  The inspections showed that there was a minor amount of wind and hail damage to the roofing.  The inspections also showed that numerous shingles were improperly installed.  Multiple shingles were attached to the roof decking with only two fasteners, and with the fasteners located within a ½ inch of the top edge of the shingles.  As a result of the improper fastening, the shingles had torn around the fasteners and were sliding down the roof slopes.  Diagrams of the roofs on each building were prepared, with the size and location of any wind or storm-related damage documented.  The flat roofs were also inspected for any storm-related damage and for other conditions that would allow water intrusion, with the observed conditions documented on diagrams of the roofs. 

The contractor representing the facility also provided engineering reports that documented wind-related structural damage to multiple buildings.   In multiple locations, the reports stated that exterior walls were leaning as a result of the application of wind loads during the passage of a tornado.  In order to determine if the walls of the buildings were leaning, EDT employed a local surveying contractor.  Based on the locations indicated to be leaning in the engineering reports provided to EDT, the surveying contractor surveyed the exterior surface of the walls.  The surveying contractor then analyzed the survey data to determine if the surface of the walls were plumb.  EDT then further analyzed the surveying data to determine if the walls were leaning and if so, if the amount of lean was within normal construction tolerances.  In locations not accessible to the surveying contractor, EDT used a plumb bob to determine if the walls were plumb.  In all locations reported to be leaning, the surveying data and the measurements taken using the plumb bob showed that the walls were plumb to within normal construction tolerances. 

The engineering reports provided to EDT also documented cracking of the brick veneer in multiple locations, with the cracking reported to be a result of wind-induced deflections of the walls to which the veneer was mounted.  The areas around the cracks were surveyed, with an analysis of the survey data showing that there was no deflection or distortion of the walls beyond normal construction tolerances.  A review of the construction documents showed that there were numerous discussions of inadequate compaction of the soil at the site, and that “significant settlement” of a portion of the structures occurred before construction of the facility was complete.  The review of the documentation and the surveying work showed that the cracking of the veneer was long-term in nature and was not a result of wind forces. 

The investigation by EDT showed that there was no storm-related structural damage to the facility.  In all locations where structural damage was claimed, a complete inspection showed that the structure was intact, with no damage.  The roofing inspections by EDT showed that a large percentage of the roofing had been improperly installed, with the improper installation allowing water intrusion.  The roofing inspections also showed that there was a minor amount of wind and hail damage to the dimensional shingles.