In 2011, a monster tornado razed large parts of Joplin, killing 160 people in a state that had no storm-shelter requirements. The city considered requiring shelters in rebuilt or new homes but decided that doing so would be cost prohibitive because the soil conditions make building basements expensive, said the assistant city manager, Sam Anselm. Even so, he estimated that half the homes that had been rebuilt included underground shelters. Schools were being rebuilt with safe rooms, he said.
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Construction standards in Moore have been studied extensively. In a 2002 study published in the journal of the American Meteorological Society, Timothy P. Marshal, an engineer in Dallas, suggested that the quality of new home construction generally was no better than homes built prior to the tornado in 1999.
Few homes built in the town after the storm were secured to their foundations with bolted plates, which greatly increase resistance to storms; instead, most were secured with the same kinds of nails and pins that failed in 1999. Just 6 of 40 new homes had closet-size safe rooms.
