Are tornadoes expected in your area?
If severe weather is possible, start the day by closing all interior doors―in addition to exterior doors, garage doors, and windows―to reduce damage risks. This should be done ahead of time before severe weather threatens and not part of an emergency response to a tornado watch or warning.
Closing interior doors can give your roof a fighting chance in a severe windstorm. If a window or door is broken by flying debris or has blown open, your house will rapidly fill with air (imagine a balloon inflating inside your house) and cause a dangerous increase in peak forces pushing on the roof. Rigorous scientific wind testing on a full-scale 1,400-square-foot single-story home at the IBHS Research Center reveals that closing interior doors helps compartmentalize the pressure inside a home into smaller areas, reducing the force on the roof by as much as 30%, which gives the roof a better chance of staying intact.