What is the quickest way to check for vertical fire spread in a balloon-frame building?

The quickest way to check for vertical fire spread in a balloon-frame building is by opening the siding panels from the outside of the fire area. Balloon-frame construction features long, uninterrupted wall cavities that can allow fire to travel vertically through hidden spaces. By accessing the siding, firefighters can directly inspect these cavities for any signs of fire extension, providing a visual indication of the fire's movement.

This method is effective because it allows for rapid assessment without the need for extensive interior demolition or reconfiguration, which can be time-consuming and potentially more dangerous as it may disrupt the building’s structural integrity or allow more smoke and fire gases to enter. By focusing on the exterior panels, firefighters can quickly gauge the situation and determine whether additional actions are necessary to mitigate the risk of vertical spread, thus maintaining better situational awareness and operational control during firefighting efforts.