Hurricane Wind Shelter Retrofit Room Guidelines for Existing Houses

The objective of this study was to develop design and construction techniques for an in-home hurricane room shelter, which is an alternative to the Federal Emergency Management Agency (FEMA) tornado safe room. Such a room will be able to withstand hurricane or tornado wind speeds up to $225\mathrm{km}∕\mathrm{h}\left(140\mathrm{mph}\right)$ and associated windborne debris. Structural calculations for known material strengths, expected wind pressures, and missile impact capacity from previous research were used as the basis for the hurricane room technology. The retrofitting is achieved through reinforcing existing walls and roofs of typical small interior rooms with plywood sheets, steel plates, anchor bolts, hurricane straps and impact resistant doors. The in-house shelter, which can also be constructed as a stand-alone unit, will offer significant occupant protection and reduce the demand on public shelters in the event of mid-Category-4 hurricane. The total cost of a hurricane room is about $3,000 including readily available materials and complete labor, a significant saving over the published cost of a FEMA tornado safe room.