Crawlspace foundations are commonly used to elevate the lowest floors of residential buildings located in Special Flood Hazard Areas (SFHA’s) above the Base Flood Elevation (BFE). This course provides guidance on crawlspace construction and supports a recent policy decision to allow construction of crawlspaces with interior grades up to 2 feet below the lowest adjacent exterior grade (LAG). In many parts of the country, a common practice is to construct crawlspaces with the interior floor 1 or 2 feet below-grade by either (1) backfilling against the exterior of the foundation wall or (2) excavating the crawlspace area to construct footings that result in a below-grade crawlspace floor. Because FEMA wishes to recognize common construction practices that do not increase flood damage. The construction practices for below-grade crawlspaces were examined to determine whether a crawlspace that was 1 or 2 feet below grade would increase the flood damage potential to the foundation walls.
This course introduces the requirements for crawlspace construction for buildings located in special flood hazard areas. Engineers and architects will gain an understanding of the design requirements for crawlspace construction. The content of this course is based on the FEMA publication “Crawlspace Construction for Buildings Located in Special Flood Hazard Areas: National Flood Insurance Program Interim Guidance”.
This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials and provide 1 hour of professional development.
Course Author: Federal Emergency Management Agency (FEMA)
At the completion of this course, the student will be introduced to the following topics:
- Common crawlspace construction practices
- Requirements for conventional crawlspace construction
- Common requirements for below-grade crawlspace construction
- General NFIP requirements that apply to all crawlspaces with enclosed areas or floors below the BFE
- Flood forces on buildings
- Flood insurance implications for below-grade crawlspaces
- Best practices for crawlspace foundations in SFHA’s
- Flood-resistant materials
- Review cases of damage caused by crawlspaces lacking proper drainage systems
- Possible drainage system options
- Utility systems protections
- Requirements for access and ventilation openings