Fire Roof Ventilation Cuts

A common time frame established for failure of a lightweight truss is between 5 and 15 minutes under fire conditions not much time for fire departments to operate within to cut a hole for vertical.

Fire roof ventilation cuts.

Cut approximately 2 to 3 inches inside the rafter. If necessary cut the roof to provide vertical ventilation. The cut is the easy part tools of the ventilation trade. The 7 9 8 ventilation cut provides a preset plan for conducting a cut.

Move back to the first outside rafter and cut a parallel. If it is decided that a vent hole is to be cut coordinate a location of the cut with the interior fire attack. In this article we ll talk about a ground ladder based roof operation on a peaked roof. A trench is cut after the main ventilation hole is cut and extended and inspection holes are made to monitor extension in the cockloft.

Vertical ventilation is the removal of super heated air gases smoke and pressure inside a closed or vent. Ventilate openings in the roof such as bulkheads skylights or scuttles. And depending on what the fire conditions are it may literally be the only option. We ve assembled the gear and now need to get it to the building in one trip.

Far too often when members cut a roof they make. Roll the second center rafter and stop at the third inside rafter. The technique of horizontal or lateral ventilation involves the. Glendale fire department ventilation training manual.

A trench is cut at least 20 feet from the main vent hole and. This will allow ventilation without having to cut the roof. This venting might suffice for the interior forces to find the fire and extinguish it.