2009 I-Codes: Summary of Changes to Flood Provisions 

International Building Code 

1. IBC 1602, 1605.2.2, 1605.3.1.2, and 1612.4. Clarify notations for flood load and 
references to ASCE 7. 

2. IBC 1612.3.2. Add requirement for applicant to provide floodway analysis to 
evaluate cumulative effect in FHAs with BFEs without floodways 

3. IBC 1807.1.2.1. Adds “on at least one side” to requirement for finished ground 
level in crawlspace/under-floor space. 

4. IBC Chapter 34. Additional statements that work on existing buildings that does 
not constitute substantial improvement (3403.2 Additions; 3404.2 Alterations) or 
substantial damage (3405.5 Repairs) is not required to comply. 

International Residential Code 

5. Table R301.2(1). Modify citation to FIRM to include all panels/dates, and date of 
FIS. 

6. Renumbered Sections in Chapter 3; flood provisions will be in Section R322. 

7. R322.1.3. Clarify the DFE to more closely align with definitions in IBC. 

8. Multiple IRC sections: Add freeboard to V Zones and Coastal A Zone (if 
delineated); matches freeboard requirement in ASCE 24. 

9. R322.1.9: 
a. Add to text for MFH to reference to V zone requirements. 
b. For MFH in floodways, change cite from IBC to ASCE 24. 

10. R322.2.2. For engineered openings, requires statement of design to be by RDP, 
clarifies the statement pertains to the openings (not installation), references ASCE 
24 as basis for design statement. 

11. R322.3.2. Modify prohibition on placement of fill beneath buildings in V Zones 
to minor grading, and the placement of minor quantities of fill, shall be permitted 
for landscaping and for drainage purposes under and around buildings, and for 
support of parking slabs, pool decks, patios, and walkways.
 
12. R408.7. Add “on at least one side” to requirement for finished ground level in 
crawlspace/under-floor space. 

13. IRC Appendix E Pools: 
a. Add text about above-ground and on-ground pools in FHAs (floodways 
and where floodways not delineated). 
b. Add text, install pools in V zones per ASCE 24.