Technical Bulletin 9, Design and Construction Guidance for Breakaway Walls Below Elevated Coastal Buildings

This bulletin provides technical guidance for the design and construction of breakaway walls below elevated buildings located in Coastal High Hazard Areas, in accordance with National Flood Insurance Program (NFIP) requirements. It details regulatory requirements, building code references, and design methodologies—including prescriptive, simplified, and performance-based approaches—for breakaway walls intended to fail under flood and wave loads without compromising the structural integrity of the elevated building. The document addresses material selection, construction details, and considerations for utilities and equipment attached to breakaway walls, as well as best practices for repairs, retrofits, and compliance with NFIP and building codes. It is intended for building professionals, code officials, and others involved in the design, construction, and regulation of coastal structures.