FEMA P55 Coastal Construction Manual, Fourth Edition - Mad Cad

Volume II Designing the builDing envelope 11
Figure 11-53.
Damaged slate roof with nails that typically pulled out of the deck. Some of the slate broke and small portions
remained nailed to the deck. Estimated wind speed: 130 mph. Hurricane Katrina (Mississippi, 2005)
Stainless steel straps, fasteners, and clips are recommended for roofs within 3,000 feet of an ocean shoreline
(including sounds and back bays). For underlayment recommendations, refer to the recommendation at the
end of Section 11.5.4.1.
11.5.6.2 Seismic
Slate is relatively heavy and unless adequately attached, it can be dislodged during strong seismic events and
fall away from the roof. Manufacturers have not conducted research or developed design guidance for use of
slate in areas prone to large ground-motion accelerations. Te guidance provided for tiles in Section 11.5.4.2
is recommended until guidance has been developed for slate.
11.5.6.3 Hail
See Section 11.5.4.3.
11.5.7 Wood Shingles and Shakes
11.5.7.1 High Winds
Research conducted after high-wind events has shown that wood shingles and shakes can perform very
well during high winds if they are not deteriorated and have been attached in accordance with standard
attachment recommendations.
Methods to calculate uplift loads and evaluate load resistance for wood shingles and shakes have not been
incorporated into the IBC or IRC. Manufacturers have not conducted research to determine suitable pressure
coefcients. Demonstrating compliance with ASCE 7 will be problematic with wood shingles and shakes
COASTAL CONSTRUCTION MANUAL
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