In December 2004, a fire destroyed three townhouses and damaged a fourth in Lorton, Va.

, just south of the nation’s capital. Investigators later determined that faulty wiring had sparked the blaze. Raul Castillo, a spokesman for the Fairfax County Fire and Rescue Department, said that fire marshals digging through the rubble uncovered an anomaly in the internal wiring at the back of one of the townhouses. This launched the fire, which spread to the adjacent townhouses. Two firefighters were hurt, one burned, while navigating the smoky townhouses in the pre-dawn darkness. Seven adults were left homeless by the fire, which marshals estimate caused at least $800,000 in damage. To avoid such a disaster, the National Concrete Masonry Association advises that you evaluate a building’s fire safety when you rent or buy a home in a multi-family dwelling, or if you are planning to lodge somewhere overnight or house your loved ones in college dormitories or nursing facilities. Buildings should contain these three components of a balanced fire-safety design: smoke detectors, sprinkler systems and concrete masonry walls between housing units. These elements, working in concert, provide the highest levels of safety and property protection. Find out if the building’s walls and floors also are constructed of concrete and concrete masonry. Concrete masonry helps keep fire from spreading and does not produce smoke or generate toxic fumes. The NCMA recommends that you urge local building-code officials to ensure that multi-family homes adhere to the principles of a balanced fire-safety design, including non-combustible concrete masonry construction.