What technique did roof companies use when vertically ventilating was unsuccessful?

When vertically ventilating a structure proves to be unsuccessful, roof companies might use trench cuts along a north-south line as an alternative method. This technique involves making a cut in the roof to create a trench that allows heat and smoke to escape, ultimately improving visibility and conditions for firefighters working inside. Trench cuts are particularly effective in large, open spaces because they help to control the fire's spread by limiting the amount of hot gases and smoke that can rise.

This approach is strategically utilized in situations where vertical ventilation doesn't achieve the desired outcome or when rapid fire spread is noted. The north-south line often aligns with the structure's layout, optimizing airflow and increasing safety for firefighters.

In contrast, cutting holes in the walls may not effectively address the vertical issues caused by smoke and heat in the upper parts of a structure. Installing fans can assist in improving air quality, but without adequately addressing the source of the smoke and heat, it may not suffice as a primary strategy. Utilizing a hose line to spray water is crucial for extinguishing fires, but it does not specifically address venting the hot gases and smoke from above in the same targeted manner as a trench cut. Thus, trench cuts represent a tactical shift aimed at improving conditions when initial vertical ventilation methods