DANGEROUS ROOF STYLES: THE EXTENDED CORNICE

DANGEROUS ROOF STYLES: THE EXTENDED CORNICE

ANTHONY AVILLO

Sometimes learning a lesson comes with a high price. Other times, luck is on your side. So it was at this particular incident at which I was truck captain. I was fortunate enough not to have to pay the ultimate price. It could`ve easily been different.

My company responded first due on the second alarm to a fire in a neighboring city. The fire, which started on the second floor of an old four-story building of ordinary construction, had quickly spread upward through a shaft to the third and top floors. Our job was to access the roof and assist the first-alarm truck crews in vertical ventilation of the roof and horizontal ventilation of the top-floor windows. Since the building was not attached to any structure of equal height and was on the corner of the block, we positioned the truck to raise the aerial to the roof on the side street (Side D).

Since one of the other captains was supervising the roof ventilation, I took my crew and began horizontal ventilation of the top floor. We accomplished this by taking the halligan tool and a short length of rope from our roof pack.1 After attaching the E-Z clip of the utility rope onto the welded D-ring of the halligan, we swung the tool into the top-floor windows, which were thermal pane and, therefore, constructed of two panes. We had to spend twice as much time taking out each window; each swing of the halligan took out only one pane and did not complete the job of effectively horizontally venting the floor.

There was no parapet, so I had to lean over the roof`s edge. From my chest up, I was over the edge so I could get the most power from the swing of the rope. A lot of smoke was coming from below, and my visibility was somewhat obscured. I never realized I was in danger.

Suddenly, one of my crew grabbed me by the legs and screamed over the roof noise, “Are you nuts? There`s nothing beneath you!” Since I couldn`t see below me too well, I heeded his advice and backed away from the edge. He told me later that the entire roof edge was shaking as I tossed the tool over and pulled it back up to set up the next tool toss.

When we got back to the ground, I looked up at the roof from the street level. Extending out from where the wall met the roof for about two feet or so was an extended decorative metal cornice. I had been lying across this unsupported, cantilevered edge without realizing it. I came very close to taking a four-story ride because I was unaware of my surroundings and had failed to size up the roof before I accessed it.

From a roof operation standpoint, this is a very dangerous area of the roof to work on if you don`t know the cornice is there and you are unfamiliar with its characteristics. Similar in characteristics to the Yankee Gutter2 as an unsupported roof structure, the extended cornice is usually much less stable and more dangerous because it is likely to be as old as the building itself and may be in a seriously weakened condition. This type of roof feature, which can be found all over the Northeast and in the Midwest, is usually on old three- to five-story buildings of ordinary construction (see photo 1). However, I have also seen it on old high-rise buildings (see photo 2) and two-story heights (photos 3 and 4). I have even seen extended cornices on wood frame, old-law tenements. They may be found at the front of any attached building; they add aesthetic value to the building (see photos 5 and 6). Buildings of ordinary construction five stories and higher usually have a parapet instead of an extended cornice, but a cornice may still be at the front of the building, and it will usually be raised above the rest of the roof level to the height of the parapet, which could be a distance of two to four feet. This will tip off the roof firefighter that it is present (see photo 7). The cornice is usually constructed of decorative sheet metal and is supported by the wooden roof members. A serious fire that originates in or extends to the cockloft may quickly weaken this structure to the point of failure. In addition, the age of the building and the subsequent years of neglect may have caused this cornice to deteriorate so that any load placed on it will precipitate its collapse. If previous fires have exposed these structures, which then may have been renovated, the cornice may have been weakened (see photo 8).

INDICATORS OF AN EXTENDED CORNICE

A few indicators may alert you to the presence of the extended cornice from the roof level, but they are not always present or reliable.

•The chimney will be offset from the roof edge for a distance equal to the width of the extended cornice (see photo 9). The chimney, if built into an exterior wall and not run through a shaft somewhere else in the structure, is usually flush with the exterior wall on most buildings of ordinary construction. This will not be the case if an extended cornice is present. If you notice that the chimney is several feet from the roof edge, beware. The area between the chimney and the roof edge may be unsupported.

•There may be a raised or depressed lip on the roof from where the extended cornice is attached to the rest of the building (see photos 10 and 11). This is a good indicator, but it is usually present only at the front of the structure in attached buildings and at the front and sides of buildings that are unattached or located on a corner. This lip may diminish or rise as the roof edge runs from front to rear (see photo 12). During night operations or where smoke obscures vision, getting too close to the roof`s edge could place a truck company member in more danger than he realizes. If these buildings are located on a corner, the sides may not be raised up and the roof will look like any roof without a parapet.

The most reliable way to recognize and point out this type of roof is through preplan inspections. Truck company members should be familiar with the types of buildings in their response area. But, even in an unfamiliar response area, doing a proper size-up from the ground level before ascending to the roof can alert the firefighter to the presence of the extended cornice. It is plainly visible from the street level if the smoke does not obscure it. The cornice will extend from the walls of the building at the roof level for a distance of about two or more feet (see photo 1). Having this information before you attempt to make the roof is vital for your safety.

SAFETY TIPS FOR ROOF OPERATIONS

Doing the following will help to make roof operations safer:

•Preplan the roof types and hazards in your response district.

•Be a student of building and roof construction. It is more important to know the building on fire than it is to know the fire in the building.

•Size up the roof before you go there.

•Work in pairs, and look out for each other.

•Be sure that the area in which you are about to step will hold your weight.

•Use extreme caution when working near the roof`s edge, especially on a flat roof without a parapet.

•Never operate between your cut and a roof edge. The fire may suddenly erupt out of your vent hole and knock you off balance (and off the roof).

•Be wary of the “Circle of Danger.” If a member operating a tool can spin around in a 3607 rotation and touch you with his hands (or worse, with the tool he is operating), then you are in the Circle of Danger and should take steps to protect yourself by letting him know you are there or (better yet) moving out of this theoretical circle.

The roof above a fire is one of the most dangerous places on the fireground. We must do our best to familiarize ourselves with the field of play before the game to maximize our chances of success. A quick glance on the way up to the roof to size up some of its characteristics will go a long way in ensuring the safety of the roof firefighters. To be aware is to be alive.


(1) Five-story corner unattached building of ordinary construction. Buildings located on corners will have an extended cornice on the front and side. Once you are on this roof, smoke emanating from windows may obscure the presence of the extended cornice, which extends out about two feet. Sizing up this building before you access the roof will enable you to operate safely once at the roof level. (Photos by Nicole Avillo.)


(2) Unattached old-style high-rise. This 15-story building has an extended cornice on all sides. Operating near the roof edge on any side of the building is dangerous and should be avoided. Note the extended cornice on the building in the foreground. Take a look around your city; these buildings are all over the place.


(3) Two-story corner building of ordinary construction. Operating on the edge of this roof, either to vent the top-floor windows or to hoist or lower equipment at the front or side, will endanger firefighters operating over an unsupported roof edge. A tip-off on the roof is the presence of the offset chimney, located over the bearing wall and away from the roof edge for a distance equal to the length of the unsupported roof edge.


(4) The same building as seen in photo 3 from the ground level. The extended cornice is plainly visible.


(5) Five-story attached multiple dwelling of ordinary construction. This extended cornice is added to the front only because the building is attached. The front is the only indication you will have of a cornice for this building.


(6) This is the same building as in photo 5. From the roof, there is no indication of the unsupported roof edge at the front. The chimneys are located over the side bearing wall and are unrelated to the front of the building. A firefighter who has not sized up this building from the ground risks death or serious injury if he steps too close to this roof edge.


(7) Five-story attached corner building of ordinary construction. The raised lip at the front and side of this roof indicates to the firefighter that the area is not level with the rest of the roof, that it is unsupported, and that no operations should be conducted from this area. Do not lean over this edge to perform top-floor horizontal window ventilation.


(8) Three-story frame unattached corner building. Fire blowing out of top-floor windows or from ignited siding may weaken the cornice. A fire in the cockloft may have the same effect. Once this building is renovated, a fresh coat of paint over the cornice may hide the fact that it was weakened by a previous fire.


(9) Five-story attached corner building of ordinary construction. This chimney is a good indicator of an unsupported roof edge. Operations between the chimney and the roof edge will endanger the roof firefighter. Once on the roof, proper size-up, along with knowledge of roof systems, will enable firefighters to operate safely.


(10) Three-story corner building of ordinary construction. The decorative cornice at the front of this building is unsupported. This feature of unsupported roof edges is present not only on large apartment buildings.


(11) Same building as in photo 10. Here the roof lip drops off slightly at the front of the building. Any difference in the roof level anywhere on the roof is a signal that firefighters should use caution in this area. The area may be unsupported.


(12) Same building as in photo 10. Running from front to rear, the diminished level of the roof edge rises gradually until it is not noticeable at all at the rear of the building. Edges that are of different levels should cause firefighters to keep clear.

References

1. See “The Roof Pack,” Anthony Avillo and Ed Flood, Training Notebook, Fire Engineering, October 1998, 14.

2. See “Yankee Gutters: The Hidden Danger,” Michael A. Terpak, Training Notebook, Fire Engineering, December 1998, 14.

ANTHONY AVILLO, a 14-year veteran of the fire service, is a battalion chief with the North Hudson (NJ) Regional Fire & Rescue (NHRF&R) and a platoon commander. He is a consultant to the Division of Training and is a member of the NHRF&R Arson/Origin & Cause Division. He is New Jersey-certified as a Level II Fire Instructor and is an instructor at the Bergen County Fire Academy in Mahwah, New Jersey.

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