A FEMA Elevation Certificate (FEMA form 81-31) is a document used to report the measured elevation of the lowest floor of a property relative to the Base Flood Elevation (BFE) published on the FEMA Flood Insurance Rate Map (FIRM) for a Flood Insurance Policy to be issued under the National Flood Insurance Program (NFIP).
The Flood insurance Rate Map or FIRM defines the boundary of those areas subject to a one-percent annual probability of flooding, or the "100-year flood" and is the basis for all local flood plain management ordinances and the National Flood Insurance Program.
The NFIP requires an Elevation certificate to obtain insurance on all Post-FIRM construction; i.e. all construction started after publication of the FIRM. The Certificate is optional for Pre-Firm construction, but may be used to determine premium rates for a Subsidized Flood Insurance Policy; or as the basis for a Letter of Map Amendment (LOMA) or Letter of Map Revision Based on Fill (LOMR-F).