47.5 MB - The Whole Building Design Guide

Figure 3-63:Both vertical faces of thecoping were attached withexposed fasteners insteadof concealed cleats.Typhoon Paka (Guam,1997)GuttersStorm-damage research has shown that gutters are seldom constructedto resist wind loads (see Figure 3-64). When a gutter lifts,it typically causes the edge flashing that laps into the gutter to liftas well. Frequently, this results in a progressive lifting and peelingof the roof membrane. The membrane blow-off shown in Figure3-65 was initiated by gutter uplift. The gutter was similar to thatshown in Figure 3-64. The building, housing the county Sheriff’soffice, suffered water leakage that shut down the county 911 callcenter, destroyed the crime lab equipment, and caused significantinterior water damage.Figure 3-64:This gutter, supportedby a type of bracket thatprovides no significantuplift resistance, failedwhen wind lifted ittogether with the metaledge flashing that lappedinto the gutter. HurricaneFrancis (Florida, 2004)3-78 MAKING CRITICAL FACILITIES SAFE FROM High Wind