The FEMA SDE Tool, available at https://www.fema.gov/media-library/assets/documents/18692, was developed to assist state and local officials in providing property owners with timely substantial damage determinations so that they can begin reconstruction quickly following a disaster.

The SDE Tool can be used when assessing substantial damage from flood, wind, fire, seismic, and other damaging events. The SDE Tool is based on the concept of using substantial damage estimates for individual structure elements to determine whether the structure as a whole is substantially damaged. The SDE Tool may be used in conjunction with an industry-accepted, residential construction cost-estimating guide.

The SDE Tool can be used to assess substantial damage to residential and non-residential structures in accordance with NFIP requirements, as adopted by the communities. The SDE Tool should not be used for structures designated by state or federal entities as historic structures because of their complex valuation unless indicated by local flood damage prevention ordinance.