Substantial improvement

Modification to or remodeling of an existing building that exceeds 50 percent of the building’s appraised value. This term includes existing buildings that are ‘substantially damaged,’ regardless of the actual repair work performed. However, the term does not include: 1) any improvement of a building to correct existing violations of state or local health, sanitary, or safety code specifications that are the minimum necessary to ensure safe living conditions, or 2) any alteration of a ‘historic building’ provided that the alteration will not preclude the building’s continued designation as a ‘historic building.’

All substantial improvements require adherence to current building codes to ensure the safety of occupants and that the building is more resilient to flooding.