47.5 MB - The Whole Building Design Guide

Figure 3-66:If mechanically attachedbase flashings havean insufficient numberof fasteners, the baseflashing can be blownaway. Hurricane Andrew(Florida, 1992)Steep-Slope Roof CoveringsFor a discussion of wind performance of asphalt shingle and tileroof coverings, see FEMA 488 (2005), 489 (2005), and 549 (2006).For recommendations pertaining to asphalt shingles and tiles, seeFact Sheets 19, 20, and 21 in FEMA 499 (2005).3.3.4 Nonstructural Systems andEquipmentNonstructural systems and equipment include all componentsthat are not part of the structural system or building envelope. Exterior-mountedmechanical equipment (e.g., exhaust fans, HVACunits, relief air hoods, rooftop ductwork, and boiler stacks), electricalequipment (e.g., light fixtures and lightning protectionsystems), and communications equipment (e.g., antennae andsatellite dishes) are often damaged during high winds. Damagedequipment can impair the operation of the facility, the equipmentcan detach and become wind-borne missiles, and water can enterthe facility where equipment was displaced (see Figures 3-20, 3-67,3-68, 3-72, 3-76, and 3-78). The most common problems typicallyrelate to inadequate equipment anchorage, inadequate strengthof the equipment itself, and corrosion.MAKING CRITICAL FACILITIES SAFE FROM High Wind3-81