Forward & Fire Facts
The popularity of log buildings is illustrated by growing numbers of log residences, resorts, and other buildings constructed in rural and suburban environments. This growth is attracting log construction to greater scrutiny as to the performance of log structures.
One frequently asked question is “How do log walls perform in a fire?” Building codes and the insurance industry look at this issue to understand the potential hazard that may result in loss of life and property. With life safety and protection of property being the goal, hazard assessment focuses on the type of construction, the availability of firefighting resources, and the proximity of the structure to neighboring structures. The key issue is time… How long will log construction be able to withstand a fire until the manpower, equipment, and water can be deployed to extinguish it? Will the occupants be able to safely leave the burning structure in that time?
Most log structures continue to be built in rural settings and rely on volunteer fire departments that often must bring water to the site. As illustrated in the Fire Facts sidebar, life safety has been dramatically improved by the requirement for residences to have smoke detectors installed and operating properly. Yet, despite the short response time of our many volunteer fire departments across the nation, the time it takes firefighters to extinguish a residential fire may be enough to make the structure and contents non-reusable. The good news is that fires per million people have been steadily decreasing. In the 10-year period between 1995 and 2005, fires and fire deaths have decreased 28%. This is primarily from efforts at prevention of accidental fires through education and regulation.
Over the years, the acceptance of solid wood walls as fire-resistive construction by code officials has been elusive. The Log Homes Council (LHC) and its Members have used various resources that relate the performances of solid wood walls to long fire endurance (see Summary of Fire Tests & Supporting Opinions) at the end of this paper). Some performed in-house tests while others tested their products in certified labs following specific standard procedures. And as the years pass, the number of fire survival stories continues to increase.
The intent of this paper is to explain the nature of fire, the burn characteristics of wood, and the code requirements that apply in the design and construction of log structures.
Fire Facts
Source: U.S. Fire Administration/National Fire Data Center, Fire in the United States 1992–2001, Thirteenth Edition, October 2004
Causes of Fires and Fire Deaths
One- and two-family dwellings, where 73 percent of the population lives, dominate the residential fire picture in 2001: 73 percent of fires, 78 percent of deaths, 67 percent of injuries, and 76 percent of dollar loss.
Cooking is the leading cause of fires and injuries in these structures.. Cooking fires often result from unattended cooking and human error, rather than mechanical failure of stoves or ovens.
Smoking is the leading cause of fire deaths. Smoke alarms and smolder-resistant bedding and upholstered furniture are significant fire deterrents.
Heating is the second leading cause of residential fires and the second leading cause of fire deaths. However, heating fires are a larger problem in single-family homes than in apartments. Unlike apartments, the heating systems in single-family homes are often not professionally maintained.
Arson is the third leading cause of residential fires but is second in residential fire deaths. In commercial properties, arson is the major cause of deaths, injuries and dollar loss.
What Saves Lives
A working smoke alarm dramatically increases a person's chance of safely evacuating a house fire before the means of escape becomes lethal.
Over 90 percent of U.S. homes have at least one smoke alarm. However, these alarms are not always properly maintained and as a result might not work in an emergency.
Residential sprinklers were found in fewer than 3 percent of homes that had reported fires in 2001. Even residential sprinklers are not a guarantee of safety from all fires. Twenty eight percent of the fire deaths are the result of intentionally set fires. Perpetrators of such heinous acts are likely to disable automatic sprinklers prior to setting fires.
