A leftover fear from my days in Omaha...I was in the twister of 1975 and it was nasty one. As kids we used to go sit on the porch when the sirens went off and watch the funnel clouds bounce around!! My house in Virginia has a room as large as my 2 1/2 car garage that is solid concrete. It has the concrete garage floor as a ceiling, concrete block (below grade) on all 4 sides as walls, 1 window, 1 door to the outside, and 1 door into the house that is fire rated steel. Best storm shelter I have ever had. I am positive that the entire house could get wiped out and that room would stay 100% intact. My only concern was the concrete ceiling coming down but it is strong enough to hold 2 vehicles and the only structure above it that could fall is the garage.
TOXIC