There are multiple documents available to help guide historic preservation in adapting buildings to be more resilient to natural hazards.
FEMA Floodproofing Non-Residential Buildings
National Flood Insurance Program Bulletin: Historic Structures
Federal Flood Risk Management Standards
FEMA Wet Floodproofing Requirements and Limitations
Flood Damage-Resistant Materials Requirements
Requirements for Flood Openings in Walls in Special Flood Zones
User’s Guide to FEMA Technical Bulletins
Funding
FEMA Hazard Mitigation Grant Program
FEMA Assistance for Governments and Private Non-Profits After a Disaster
FEMA Public Assistance Hazard Mitigation
FEMA Building Resilient Infrastructure and Communities
FEMA Safeguarding Tomorrow Revolving Loan Fund Program