What is a vulnerability associated with Type 3 construction?

Type 3 construction, often referred to as "ordinary construction," incorporates exterior walls made of non-combustible materials while interior elements may be made of wood. One notable vulnerability associated with this type is hidden fire spread.

In Type 3 structures, ceilings, walls, and floors may have concealed spaces where fire can travel unnoticed. This hidden fire spread can occur through attic spaces, wall cavities, or floors, allowing a fire to extend beyond its initial point of ignition without detection. The materials used in the interior—typically wood—can ignite and may provide fuel for fire that spreads rapidly through these concealed spaces.

Recognizing this vulnerability is crucial for fire investigators and firefighters as it emphasizes the need for thorough inspections and assessments when responding to fires in such construction types. Identifying hidden areas where fire can propagate unnoticed can significantly impact fire suppression strategies and enhance overall safety during and after a fire incident.