The modern American home has changed considerably from the home of our parent’s and grandparent’s generation. Homes today tend to be larger with open floor plans. Often these residences are built using lightweight, engineered building materials and decorated using home furnishings with synthetic fibers that were not seen in a home 40 to 50 years ago. Recent testing by Underwriters Laboratory (UL) show that these changes, among others, leave a new home at increased risk to fire damage than the homes of a prior generation.
In 2012, UL conducted fire tests of 3 modern, open-concept homes with modern furnishings and compared the results with 3 legacy homes (1950’s- 1970’s era) with legacy era furnishings. The results revealed that the legacy homes allowed an average of 17 minutes after fire inception for occupants to escape the home safely. Modern homes allowed only 3-4 minutes for safe evacuation. Flashover time (the time it takes an object to reach auto ignition temperature) for the modern home is 5 minutes versus 29 minutes for a legacy home. Additionally, firefighters must act quicker in order to extinguish the fire before the structural collapse of a modern home. While legacy homes averages a structural collapse rate of 40 minutes, modern homes, on average, collapsed after only 10 minutes. Given an average response time of 5 minutes for municipal paid fire departments there is little time to engage and control the fire before structural collapse ensues.
So, what is behind the rapid fire spread in modern homes? The first tenet of fire control is compartmentalization, which slows the fire’s growth and ability to spread. The open floor plan of a modern home allows smoke and fire to spread quickly from room-to-room and allows the fire to grow too large, too quickly to be controlled. Also, thinner, lightweight building materials such as engineered lumber, hollow core interior doors, thermal windows, plywood and oriented-strand board (OSB) have quicker flashover times. These materials burn and collapse quicker than the real wood boards, brick and other natural materials of legacy homes. Interior furnishings like drapes, carpeting, vinyl flooring and modern furniture made with synthetic fibers all have quicker flashover and burn times than the materials and furniture found in legacy homes. Polyurethane foam, found in most furniture today, is another reason for the rapid fire spread.
With the trend toward homes with open floor plans and less interior walls, built and furnished with materials that demonstrate a quicker flashover rate and burn rate, what can today’s homeowners do to help protect their homes and families? There are several strategies that can compensate for more hazardous designs and furnishings of today’s homes. The first thing homeowners can do is install a residential fire sprinkler system which will hinder the ability of the fire to rapidly spread throughout the home. Also, consider installing a wired smoke detector network throughout the house to detect smoke and release an audible alert anywhere in the house. Establishing and regularly reviewing a fire evacuation plan for all home occupants can help homeowners plan for the unthinkable. A final recommendation is to keep your bedroom doors closed. Remember, the first tenet of fire control is compartmentalization.