CONCRETE SAFE ROOMS FAQ

Source:www.stonediamondtool.com Date:2019/3/15 Read:484

Learn about structures built to provide “near-absolute protection” during windstroms

What Is a Safe Room?

A safe room is a small, windowless chamber specifically designed and constructed to meet Federal Emergency Management Association guidelines, which are outlined in the publication Taking Shelter from the Storm: Building a Safe Room for Your Home or Small Business.

These structures are built to provide “near-absolute protection” for the occupants during extreme windstorms by meeting the following criteria:

· They are adequately anchored to the home’s foundation to resist overturning and uplift.

· The connections between all parts of the safe room are strong enough to resist failure during high winds.

· The walls, roof, and door are designed to resist perforation by windborne missiles.

· The walls of the safe room are completely separate from the structure of the home, so they will remain standing even if portions of the home around it are destroyed.

Safe room walls and roofs can be built using a variety of materials including reinforced concrete, reinforced concrete masonry or combinations of wood frame and steel sheathing or concrete masonry infill. The doors are typically made of high-gauge steel tested to resist high wind forces and perforation by windborne debris.

Why Build a Safe Room Using Concrete?

By far, the biggest danger to people and property during tornadoes and hurricanes is the flying debris carried by the high winds. Any heavy windborne object can become a missile that can easily penetrate building walls.

To duplicate the effects of windborne debris, researchers at Texas Tech University’s Wind Engineering Research Center shot wall sections with 15-pound 2x4 lumber to simulate debris carried in a 250 mph wind. These conditions cover all but the most severe tornadoes. They tested 4x4-foot sections of concrete block, several types of insulating concrete forms, steel studs, and wood studs to rate their performance. The wall sections were finished as they would be in a completed home, with drywall, fiberglass batt insulation, plywood sheathing, and exterior finishes of vinyl siding, clay brick, or stucco. All the concrete wall systems survived the tests with no structural damage. Lightweight steel and wood-stud walls, however, offered little or no resistance to the test missiles.You can build concrete safe rooms that withstand such impacts using a variety of methods: cast-in-place concrete, concrete blocks, 4- and 6-inch flat ICF walls, and 6-inch waffle grid ICF walls. In addition to extreme wind events, concrete safe rooms can provide protection from other disasters, including earthquakes, fires, and blast forces.