Which of the following materials is acceptable for fire blocking walls in wood frame construction?

In wood frame construction, fire blocking serves a critical purpose by preventing the spread of fire within concealed spaces. The correct choice highlights the use of 23/32 inch wood structural panels as a suitable material for fire blocking walls. This thickness is deemed robust enough to resist the passage of fire and smoke, effectively contributing to the building's overall fire safety features.

Moreover, the requirement that joints be backed by the same or equivalent material enhances the structural integrity of the fire blocking. This approach ensures that there are no gaps or weak points that could allow fire to breach the barriers created by the fire blocking walls.

Other materials mentioned in the options do not consistently meet the necessary standards for fire blocking. For example, though 1/2 inch gypsum board is commonly used in fire-rated assemblies, it may not always fulfill the structural requirements when specifically considering wood frame fire blocking applications. Wood planks of any thickness are not adequate since they fail to provide a uniformly fire-resistant barrier unless specified for a particular application. Fiberglass insulation, while it may offer thermal properties, does not serve as a structural material and lacks the necessary rigidity to act as effective fire blocking on its own.

Thus, using 23/32 inch wood structural panels, particularly with proper joint backing,