The back of a commercial occupancy typically provides the best roof access for aerial ladders. Less customer parking (obstruction), fewer windows and doors to work around and parapet walls are not as common. Most commercial signage and aesthetic architecture is in the front of the structure allowing for simple access to the roof in the back.
The back side of a commercial structure can also have limited access for apparatus due to an alley, loading docks, or even just trash receptacles. Newer commercial construction in neighborhoods is being held to higher standards and parapet walls may wrap the entire structure to hide the sight and sound of roof top units from neighboring residential communities
In short I am setting you up; there are just as many reasons the back of an occupancy will provide good access as there are reasons it will hinder operations. With that said, if we don’t prepare for the unexpected, the unexpected is what we will find when the time comes so try hitting your commercial occupancies with ground ladders in training.
When aerial access is limited at a commercial structure ground ladders are consumed quickly. Larger occupancies with built up roofs will demand more resources pure and simple. Even if a commercial occupancy has good aerial access, an aerial ladder is still only one ladder. With more resources operating on a roof with a larger footprint, the more means of access and egress must be provided. It is here is where we are seeing some of the greatest short comings in ground laddering.
Truck 1 arrives and is assigned to go to the roof on a commercial occupancy. The crew is trained to use the aerial for this operation and as the driver is setting up the stick or the bucket, the rest of the crew is assembling tools and planning for a potential flat roof vent.
With the stick up, the crew is headed up as not to delay the ventilation but when they reach the top of the wall they find a 6′ parapet and need to drop a roof ladder into place to access the deck. The already busy truck officer now makes a request to the IC to have the next in company throw a secondary means of egress for them but the parapet information is not relayed. E4 arrives, throws a 35′ from the truck to the roof and walks away. Did they improve the situation for Truck 1 with the 1 ladder?
The answer is NO! In the presence of a substantial parapet wall on a flat roof, every single access/egress point will need 2 ladders to serve any purpose. One from the ground to the wall and one to transition to the roof. If you are in a department with just a couple, or no truck companies this message needs to be communicated out to all crews who may find themselves with an assignment to support roof operations by providing secondary means of egress ladders. As a whole the fire service has really latched on to roof ladders being a peaked roof tool because of the hooks. It is frustrating to see how often they can be utilized as a straight ladder on the fire ground but aren’t. It is even more frustrating when “roof” ladders are not going to flat roofs. To avoid some frustration here is a simple drill and way to proactively address it.
Find a commercial structure in your area with a parapet wall that is at least the height of a firefighter so a ladder is required to transition in full gear with tools. Park the rig and leave it so you are only accessing with ground ladders. Part one of the drill is gathering equipment; just working through how the 2, 3 or 4 of you are going to carry the 2 ladders, let alone tools needed for a ventilation operation will spark some good discussion.
Given the opportunity you should get out in your districts and pre-practice not just pre-plan at these locations. Look for scuppers or other visual clues that might key you in on parapet wall height or identify locations or sides of the structure where the the parapet wall is non existent or low enough that a ladder is not required