Check local building codes and permit requirements
Choose a safe location away from flood zones and unstable soil
Decide between above-ground and below-ground shelter types
Determine shelter size based on number of occupants
Select materials rated for wind, impact, and debris resistance
Hire a qualified structural engineer or shelter contractor
Design the shelter to meet FEMA and ICC 500 standards
Plan ventilation, drainage, lighting, and emergency communication
Include a reinforced door with secure locking hardware
Provide enough seating, storage, and emergency supplies space
Excavate and prepare the site if building underground
Pour a reinforced concrete foundation and walls
Install steel reinforcement and anchor connections properly
Build the roof or ceiling slab to resist extreme loads
Seal all joints and penetrations against water intrusion
Install a sump pump or drainage system if needed
Add an emergency exit or secondary escape route
Install ventilation openings with protective covers
Finish interior surfaces and mount emergency supplies
Test the door, ventilation, and drainage systems
Inspect the shelter for compliance before use
Maintain the shelter regularly and replace damaged components