Technical Bulletin 1, Openings in Foundation Walls and Walls of Enclosures (2020)

This bulletin provides technical guidance on the requirements for flood openings in foundation walls and enclosure walls below elevated buildings located in Special Flood Hazard Areas, as mandated by the National Flood Insurance Program (NFIP). It details compliance with NFIP regulations, relevant building codes, and standards such as the International Residential Code, International Building Code, and ASCE 24. The document covers the design, installation, and documentation of both engineered and non-engineered flood openings for various building types, including single-family homes, townhouses, manufactured homes, and accessory structures. It also addresses the use of the NFIP Elevation Certificate for documenting compliance and insurance purposes.