Date Published: November 2015
The FEMA Elevation Certificate web page and the NFIP Elevation Certificate and Instructions web page contain a Federal Emergency Management Agency (FEMA) form that can be used to have a professional engineer certify elevation which in turn can support a Letter of Map Revision (LOMR) application, as well as a FEMA form that can be used to certify flood proofing for non-residential buildings.
For residential buildings, the National Flood Insurance Program that those certificates are designed for only recognizes certain exceptions to allow flood proofing for residential basements, on a community-by-community basis, and in those cases the local National Flood Insurance Program (NFIP) administrator would have the form that they use for that purpose.
Since the 811 PRA program requires flood insurance through NFIP for structures in the 100-year floodplain (section III.c.u), (unless the 811 PRA project involves a National Register listed historic property, which has an exemption from NFIP rules), residential flood proofing above the basement may or may not be feasible as an alternative to elevation in 100-year floodplain locations.
On the other hand, for residential buildings located in the 500-year floodplain, flood proofing to the 500 year flood level in lieu of elevation would be permissible, but rather than the FEMA non-residential form you would likely just use a certification from the architect and engineer that the flood proofing is acceptable.
If you do happen to be looking at a National Register historic property in the 100-year floodplain regarding this issue, there is some initial guidance in the National Institute of Building Sciences Whole Building Design Guide; our historic preservation staff in DC have been working on additional guidance in this regard.