Updated Edition of Engineering Principles and Practices for Retrofitting Flood-Prone Residential Structures (FEMA P-259) Available
FEMA has released an updated edition of Engineering Principles and Practices for Retrofitting Flood-Prone Residential Structures (FEMA P-259). This publication was created to provide engineering design, economic guidance, and best practices to engineers, architects, and local code officials best practices and guidance on residential retrofitting techniques for structures that are flood-prone.
Retrofitting flood-prone residential structures helps achieve an important objective of the National Flood Insurance Program (NFIP), to break the cycle of repetitive flood damage. Many buildings have been flooded, repaired, and flooded repeatedly. In some floodplains, this cycle occurs every few years. FEMA estimates that buildings that meet or exceed the NFIP minimum floodplain management requirements incur, on average, 65 percent less flood damage than buildings that predate adoption of local floodplain management requirements. In general, buildings that were constructed before the adoption of local floodplain management requirements may not have been constructed with features that reduce flood damage. Owners of these buildings may be interested in the retrofitting measures and best practices described in this publication.
The focus is the retrofitting of one- to four-family residences subject to flooding situations without wave action. The publication presents various retrofitting techniques that provide both active and passive efforts and employ both dry and wet floodproofing measures. These include elevation of the structure in place, relocation of the structure, construction of barriers, dry floodproofing (sealants, closures, sump pumps, and backflow valves), and wet floodproofing (flood damage-resistant materials and protection of utilities and contents).
Existing data and current standards have been used to inform this publication. Detailed sections on evaluation, planning, and retrofitting design measures, along with updated case studies of completed retrofitting projects, are included. The publication was used to update content for the FQS training course related to Retrofitting Flood-Prone Residential Structures.
