If your home or business is located in a special flood hazard area (SFHA), you are subject to substantial damage or improvement requirements. Any repair, reconstruction, alteration, or improvement to a building in which the cost equals or exceeds 50% of the market value of the building, the existing building is then required to meet the same standards as a new building. For residential structures, these requirements typically mean raising the living area of the building to the design flood elevations under current codes.