Survivable buildings: Are you prepared?
Constructing survivable buildings has been a necessity for cities and counties in coastal areas because of the constant threat of hurricanes and other natural disasters that can result in billions of dollars in damage. However, with acts of terrorism being a reality in the United States, survivable buildings have become a concern to every region. As a result, critical local governmental facilities must be capable of withstanding and fully functioning prior to, during and after emergencies.
The primary factor in a building’s survivability is protecting the exterior surfaces from disastrous forces piercing the building’s envelope. Doors, service access panels; windows; and fresh air, roof and exhaust air vents must be designed specially to resist all forces of intrusion, because the building’s envelope is only as strong as its weakest link.
Those elements can be architecturally and structurally designed to protect the building from winds and to resist the impact of airborne projectiles. High-strength and reinforced concrete, as well as strengthened concrete block and masonry units, provide a strong and dense protective exterior wall surface.
The roofing system is the most difficult building envelope feature to design for survivability. Certain specialized roofing systems are appropriate, including those that are applied to the roof decking in a series of adhered layers with mechanical fasteners. As the roofing elements get closer to the roof-wall connection, the fasteners’ size and strength should increase for additional protection.
Glass windows and doors are commonly perceived as vulnerable areas in a building. New glass formulations, however, often are composed of multiple layers of tempered glass, a poly-carbon inner core and other products that resist impact. Those types of glass can resist a 45-caliber bullet fired at point-blank range without piercing the protective layers.
Because it is critical that a community’s Emergency Operations Center continue to function during a local emergency, those buildings should be designed with the basic elements of survivable buildings. Also, each critical system in the centers should have back-up capabilities.
The research in designing survivable facilities is ongoing and changing. Local government leaders should remain informed about the potential threats and specific needs of critical facilities. A risk assessment can evaluate a building’s preparedness and analyze its likelihood of surviving a disaster.
I.S.K. Reeves is president of the Winter Park, Fla.-based Architects Design Group.