How long will rough cut timber typically last in a fire?

The correct answer indicates that rough cut timber typically lasts approximately 5 minutes per inch when exposed to fire. This duration is a guideline based on the burning characteristics of wood, taking into account that rough cut timber has a higher surface area due to its texture compared to smooth-sawn lumber. The increased surface area allows for more rapid absorption of heat and oxygen, leading to a faster combustion.

Understanding the timeframe is crucial for fire safety inspections, as it helps inspectors assess the fire-resistive qualities of structures. Knowing that rough cut timber has a defined burning time also aids in determining safe egress times and in evaluating the overall risk associated with the materials used in construction. This knowledge is essential for proper fire safety planning and the implementation of effective preventive measures in buildings constructed with timber.