In tornado-prone areas, safe rooms-located either inside or outside a home-can save lives. The Federal Emergency Management Agency (FEMA) recommends building these windowless shelters using high-strength materials, such as reinforced concrete or masonry, so they can resist winds of up to 250 mph.

Lite-Form International, Sioux City, Iowa, recently introduced a kit that allows builders to quickly erect an all-concrete safe room that meets or exceeds FEMA wind-resistance guidelines. The tornado haven's walls and roof are formed with rigid polystyrene stay-in-place forms. With the addition of reinforcement, the system produces a structure Lite-Form claims is up to eight times stronger than a wood-frame building. The standard safe room, with 6-inch-thick walls and rebar at 2-foot spacings vertically and horizontally, can resist winds up to 250 mph.