Design and Construction Guidance for Breakaway Walls: Below Elevated Buildings Located in Coastal High Hazard Areas in Accordance with the National Flood Insurance Program [open pdf - 7MB]
"This Technical Bulletin presents three design methods that are consistent with the NFIP [National Flood Insurance Program] regulations: a prescriptive design approach, a simplified design approach, and a performance-based design approach. Regardless of the approach used, breakaway walls must be designed and constructed to meet applicable building or residential codes, such as the International Building Code® (IBC®) or the International Residential Code® (IRC®), respectively. In many cases, design wind speeds will exceed the prescriptive limits specified in the governing residential code, which means designs must be in accordance with the governing building code or other approved standard. For example, the prescriptive design provisions of the 2006 IRC are not applicable to designs where 3-second gust design wind speeds exceed 100 mph; thus, residen¬tial structures in these areas must be designed in accordance with the IBC or other standard referenced in the IRC (see IRC Section R301.2.1.1). The primary reference for wind and seis¬mic loading in building and residential codes is Minimum Design Loads for Buildings and Other Structures (ASCE 7-05)."
Technical Bulletin 9
Federal Emergency Management Agency: http://www.fema.gov/