Coastal Construction in Rhode Island


Within flood hazard areas of Rhode Island, all new construction or substantial
improvement (cost > 50% market value) shall be designed and constructed to
resist flood hazards and flood loads per the following codes:
  •  IBC 2012 Section 1612:  Flood Loads
  •  IRC 2012 Section R322:  Flood Resistant Construction
  •  ASCE 7-10 Chapter 5:  Flood Loads
  •  ASCE 24-05 Flood Resistant Design&Construction
  •  Rhode Island Building Code SBC-1 (2013) Appendix G

The base flood elevation (BFE) will need to be determined for the project.   The
BFE is the height above sea level using NGVD 29 or NGVD 88 reference datum for
the 1% flood event.   Flood Insurance Rate Maps (FIRMs) show special flood
hazard areas (SFHA).  Digital Flood Insurance Rate Maps (DFIRMS) have been
updated for all RI communities.   For Maps, see the following links...

DIRMS have the following zones:
  • ZONE VE (commonly referred to as "V Zones" or CHHZ "Coastal High
    Hazard Zones")
  • ZONE AE (contains both "A Zones" and CAZ "Coastal A Zones"*)
  • ZONE X
*Coastal A Zones (CAZ) are defined as zones where breaking waves are between
1.5 feet and 3 feet.   It is necessary to determine whether a structure located within
Zone AE falls within CAZ.  There are new lines on the DFirms as of 2014 that show
white lines with two black dots - these are the boundary areas of what is called
"limits of moderate wave action".   Coastal A Zones (CAZ)and V Zones (CHHZ) are
areas that are subjected to high-velocity wave action and must meet the provisions
of Section 4 of ASCE-24.    

Buildings located in a SFHA require an Elevation Certificate (EC).   This certificate
is usually completed by a surveyor or civil engineer but can be an architect or other
engineer.  Follow this link for EC information:

The ASCE 24 is a referenced standard in the International Building Code. Any
building or structure that falls within the scope of the IBC or IRC that is proposed in
a flood hazard area is to be designed in accordance with ASCE 24. Highlights
include: Building Performance; Flood-Damage Resistant Materials; Utilities and
Service Equipment; Coastal A definition and Siting Considerations.

Additional References and Recourses:
Structural Engineers Association of Rhode Island