BY DOUG LEIHBACHER
“Getting the roof” is an intrinsic part of firefighting operations at most common commercial and residential fires. The primary reason for operating on a peaked roof is to perform vertical ventilation or to extinguish a chimney fire. When directed to carry out these duties, ladder companies who are accustomed to venting flat roofs should be cognizant that the difficulties of working above the fire are increased when the roof is pitched. Getting into position and completing the job require extra time and care. Movement should be measured and methodical. The degree of hazard depends primarily on the pitch of the roof, the type of roof construction, the roof covering, the amount of fire, and the weather conditions. Using a roof ladder can make vertical ventilation feasible on steeply pitched roofs when it would otherwise be unsafe or impossible.
With the exception of top-floor fires, cutting the roof is not necessary at many, if not most, newer single-family residential fires, and members should not be sent to the roof unnecessarily. A single-room fire on a lower floor, for example, can usually be handled with proper horizontal ventilation on the fire floor and floors above coupled with an aggressive interior attack, especially in houses built with platform framing. If the response is not delayed and the gypsum board in the ceiling and walls is properly installed, fire penetration into the structural voids is usually minimal. Positive-pressure or exhaust fans ordinarily are all that are necessary to remove the smoke once the fire is out, and any holes in the roof amount to needless, ancillary damage.
Notwithstanding this factor, fires do enter voids and travel vertically to attic spaces. A check of the attic or cockloft is always warranted before taking up whenever a fire is on a lower floor, including the basement. This is especially true in older homes, which may have balloon framing, limited or no fire stopping, and plaster-over-wood lath construction. The attic can be checked by way of an interior stairway using a thermal imaging camera or by making an inspection hole.
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Vertical venting becomes necessary when fire originates in an attic or spreads there from below through the eaves, balloon-framed exterior walls, interior shafts, or pipe chases. When the inspection of the attic reveals the presence of flame or pressurized smoke, the roof should be opened above the hot spot without hesitation. Similarly, any fire traveling vigorously in a balloon-framed wall is headed to the attic, and a properly located ventilation opening above it is needed to impede horizontal spread in the attic. Therefore, it is a good practice to ladder the roof with the aerial as a matter of routine. In this way, if fire should spread to the attic, roof access can be accomplished immediately.
SIZING UP THE ATTIC
Attic fires can result from lightening strikes, defective chimney linings, incorrectly installed flue pipes, damaged and arcing wires, human errors, or fire traveling vertically from below. Owing to limited human activity, fires originate in attics infrequently. When they do occur, they often develop quickly. Since smoke rises, fires that originate in attics often go unnoticed by building occupants on the floors below and thus go unreported until smoke becomes visible from the outside. Occupants frequently do not smell smoke initially; and if smoke detectors are not mounted in the attic, occupants are often unaware of the fire burning above them. As a result, attic fires can become well involved before firefighters’ arrival and often necessitate aggressive hoseline operations that, in turn, can result in excessive water damage to the floors below. Moreover, this advanced fire development can result in tenuous roof stability for arriving ventilation teams.
Attics are of two types: finished and unfinished. Finished attics provide additional living space and have enclosed walls and ceilings. They commonly contain ordinary furnishings and include numerous built-in void spaces. A finished attic is distinguishable from an unfinished attic by the presence of dressed windows or skylights. These windows provide effective ventilation points, which can be enlarged if necessary. Access to finished attics is usually by way of an interior stairwell. A tactical consideration in finished attics is the knee wall that runs below the pitched roof spans. It usually serves as an additional storage area and, hence, may add an additional fuel load. An intense fire behind the knee wall will initially weaken the lower part of the roof before spreading to the ridge.
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Unfinished attics are likely to be windowless, have heavy fire loading, and contain unprotected structural members. At the gable ends, there often are louvered vents near the peak of the roof that provide potential ventilation points for when advanced conditions make stepping on the roof unsafe. Smoke is often issuing from them on arrival, and removing/enlarging these natural vent openings, although not ideal, can be a way to relieve superheated gases from the attic. Flooring in unfinished attics often covers only part of the floor area, usually in the center, and interior crews must be careful not to fall between beams when working laterally. There is a positive side to this partial floor area in an unfinished attic: Once vertical ventilation has been effected, a hole can be poked in the ceiling from below to provide an opening through which a hoseline could be directed to initially darken down the fire. Using this tactic, the attic fire is treated similarly to a cockloft fire with the ceiling pulled from below, except in the center, where the flooring prohibits penetration. When coordinated with vertical ventilation, this can slow the fire’s progress until entry into the attic can be gained.
Entry to unfinished attics can present a difficulty. Access is either by a scuttle in a closet or a folding wooden drop ladder that recesses into the hallway ceiling. At a well-involved fire, this drop ladder may be weakened, destroyed, or simply hard to find in the smoke, requiring the use of a collapsible ladder from the apparatus to gain access. Moreover, weakened springs may cause the ladder to drop without warning.
Once the fire is darkened down, extensive additional cutting is often necessary at attic fires as part of overhaul. Fire entering an attic penetrates the roof boards quickly, where it smolders in the tar paper beneath the roof shingles. Comprehensive overhaul is often needed, requiring crews in the attic to work closely with members on the roof. Frequently, large sections of the roof must be removed to prohibit rekindle.
THE BENEFITS OF VERTICAL VENTILATION
Attics trap tremendous amounts of heat and smoke that can sometimes result in smoke or backdraft explosions. Vertical ventilation is especially important at attic fires not only to localize the fire and prevent lateral spread but also to preclude smoke explosions. It should be performed once hoselines are stretched but before crews make entry to the attic from below. Once the heat is released vertically, the danger of an explosion is reduced.
Water damage is a fundamental concern whenever an attic is involved. Unfortunately, fire banks down quickly and spreads horizontally at a rapid pace in attics, often requiring extra water. However, additional water is of little use if there is no exit strategy for the heat. This swift fire spread is especially evident in unfinished attics, where open framing and roof boards along with combustible storage provide plenty of fuel.
The safety of the interior hose crew is also a primary ventilation concern. The pitch of the roof and the low, angled ceilings leave little space for heat to collect overhead. With no place to escape, the heated gases radiate down to floor level, punishing the crews operating therein. Smooth bore or automatic nozzles set to straight stream are the only option in attic fires. The use of a wide-angle or fog pattern will create steam that will push down on the nozzle crew and result in scalding and steam burns even with the roof open. Use of a fog pattern should be limited to smoke removal after the fire has been knocked down. Regardless of the type of nozzle employed, it is essential to create an opening large enough for the superheated gases to escape.
ROOF SIZE-UP
Roof size-up should begin with a scan of the building and the roof’s surface. How old is the structure? Is there a skylight? Is there ice or snow on the roof that adds weight and could make for slippery conditions? Does the roof surface face north, or is it in a shady area where slippery moss forms? Are the roof shingles falling? Of what is the roof surface constructed? Is it made of cedar shakes, Spanish (ceramic) tiles, slate, asphalt shingles, or corrugated metal? Of these, the asphalt shingles provide the best traction. They are not subject to breaking or cracking beneath your weight like tile or slate. They are less slippery when wet but will become slick when heat causes the tar to melt. Once impinged on by fire, however, asphalt shingles create smoky conditions. Cedar and asphalt shingled roofs also reveal cues about the fire below more readily. Hot spots and signs of weakness, while not obvious, are easier to see if you look closely.
Slate and ceramic tile roofs provide little traction and their fragility can cause them to break beneath your weight, causing you to go down. Moreover, they can disguise a weakened roof structure below. For these reasons, the use of an aerial is strongly recommended on slate and Spanish tile roof surfaces. At a minimum, a roof ladder should be employed.
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Another hazard associated with slate roofs is the sharp fragments that fall from the roof while it is being opened. Slate and ceramic tiles must be broken away before a cut can be made. Although they are brittle and break away easily, when they slide off the roof, they become a hazard to members walking below. Corrugated metal, slate, and tile roof surfaces can be problematic even with the aid of a roof ladder. Because the hooks cannot dig into the ridge, it is possible for them to become dislodged, causing firefighters to fall. This happened to two Ohio firefighters, who were seriously injured during a recent training exercise on a corrugated metal roof.
Roof ventilation on peaked roofs is most safely accomplished from a tower ladder bucket or the tip of an aerial. Such apparatus provide a stable, flat surface from which to work and support your weight independently. The use of a life belt tether can increase safety. However, to use this approach, it must be possible to maneuver the aerial or elevated platform into position, and that is not always feasible. Of course, whenever a lightweight or timber truss roof is encountered, aerial apparatus should be considered the only option for vertical ventilation. No firefighter should set foot on a truss roof that has been exposed to heat or flame with or without a roof ladder. A roof ladder should never be used on trusses because of the lack of a ridgepole to support it.
Although it is important for the chief officer and each truck firefighter to take a close look at the roof before climbing onto it, with truss roofs, it is often not possible to tell if trusses are present on arrival. They look the same as rafter roofs from the outside and are used even in complex roof designs. The time to size up a truss roof is during building inspection. Trusses are now the most popular method of constructing residential roofs. When a new home or development goes up, stop by, take a look at it, and make a note of the location if lightweight truss construction is used.
Similarly, if a fire is well advanced in a traditional roof space and you note evidence of sagging or weakness between rafters during roof size-up, the cut should be made from an aerial device only. If no aerial is available and the roof appears ready to vent itself, firefighters should not tread on it. As with a flat roof, a peaked roof should always be tested for sponginess before committing to it. Heavy fire in an attic space burning unchecked for 20 minutes or more can herald an impending collapse. When such advanced fire conditions make it unsafe to place a firefighter on a roof, and an aerial cannot be positioned, effective ventilation cannot be safely accomplished from a roof ladder.
WORKING FROM ROOF LADDERS
When aerial access is not possible at a steeply inclined, rafter-constructed roof, and roof conditions are tenable, ventilation can be safely accomplished from a roof ladder. The steeper the pitch of the roof, the more difficult it is to walk and the more necessary it is to use a roof ladder during ventilation. Firefighters are less inclined to cart a roof ladder onto a roof on which they can walk. However, though not always necessary, using a roof ladder can be beneficial even on more moderately sloped roofs because it provides a point of orientation. If heavy smoke reduces visibility, firefighters venting the roof can become disoriented. When this occurs, the roof ladder can provide a way to safely retreat much as a hoseline leads firefighters to the means of egress within the structure.
In addition, the roof ladder provides a margin of safety on a moderately pitched icy roof. Finally, the roof ladder distributes the firefighter’s weight, thus decreasing the likelihood of stepping through a weakened roof deck. Often, roof sheathing is not designed to hold the weight of a firefighter, especially if it is weakened by rotting or fire below. In newer homes (1950s-1990s), the roof sheathing is usually plywood and reasonably strong. However, in many older homes, only 1 2 2 furring strips spaced 6 inches on center are used to span the rafters. This construction is used in roofs made of cedar shakes and should never be walked on. Also, note that rafters supporting pitched roofs are usually of smaller dimensions than floor joists. Many roofs are supported only by 2-inch 2 6-inch or 2-inch 2 8-inch structural members. Most recently, truss roofs with flake board sheathing have been replacing plywood and rafters. Standard roof ladders come in several sizes, ranging from 12 feet to 18 feet. National Fire Protection Association (NFPA) 1901, Standard for Automotive Fire Apparatus, 2003 Edition, requires ladder companies to carry two roof ladders with folding hooks and that engine companies carry one roof ladder. In selecting the roof ladder, remember that it should extend from the roof ridge to the eaves without overhanging rungs. If the ladder is too short to reach down to the eaves, it can be difficult to shift from the ground ladder to the roof ladder and back.
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On the other hand, take care when climbing onto a roof ladder that is too long for the job and extends past the eaves. If a firefighter climbing onto the roof ladder places his weight on the overhanging part, he may dislodge it and ride it to the ground. The hooks of the roof ladder should be pushed over and set into the ridge before climbing onto it. To make the transfer from ground ladder to roof ladder as safe as possible, it is essential to extend the ground ladder four to five rungs above the eaves with the butt footed. The placement of the ground ladder is important. Whenever possible (sometimes factors such as shrubbery, fences, or grade interfere with accomplishing this), the ground ladder should be positioned along the roof edge to the point where the roof ladder is going to be used. This alleviates the need to crawl along the roof ridge with the roof ladder in tow until the point of operation is reached.
Roof ladders weigh approximately 30 to 60 pounds, depending on length; one firefighter can easily carry it by placing an arm through the midpoint of the ladder and resting it on his shoulder. Engage the hooks on the ground prior to ascending to the roof. The firefighter carrying the roof ladder should be the first one to climb to the roof, followed by a second firefighter, who carries the saw. Raising the roof ladder is always a two-person job. If three firefighters are available, the third should carry the ax and hook. Once the roof ladder is placed with the hooks set into the ridge, the first firefighter transfers his weight onto it. The saw is then passed to the first member, who ascends the roof ladder to the ridge. The second member then steps onto the roof ladder.
SAFE OPERATIONS
Before going to the roof, be sure that you have working radios so that you can monitor the progress of the engine companies below and receive transmissions from the incident commander. During peaked roof operations, do not try to carry too much equipment. One of the pitfalls of operating on steep roofs is that there is no place to put down the tools. The old sailor’s adage “One hand for the ship and one hand for yourself” applies here. You’ll need one hand free to prevent losing your balance. If you can grip a hook and an ax in one hand, fine, but don’t try to brandish the roof ladder too. Likewise, this is no time to rush. Equipment should be passed back and forth methodically so that each member can climb safely with one hand on the ladder. When necessary, tools can be hung from the rungs of the roof ladder to free a hand. A shoulder strap for the saw frees a hand for gripping.
When moving on a peaked roof, away from the roof ladder, climb up to the ridge and crawl along there, straddling it as you go. In this way, your weight is balanced and if you do slip, you can grab hold of the ridge. Whenever operating on a peaked roof, maintain as much of your body in contact with the roof surface as possible. Keeping a knee, boot, and gloved hand in contact creates three points of friction and a low center of gravity. Unless the roof is almost flat, do not stand straight up; keep the knees bent.
The officer or the firefighter who is second to climb the ladder typically acts as a safetyman for the member using the saw. Once cutting begins, the safetyman should keep a firm grip on the first member’s belt or safety harness to provide support and balance. Whenever possible, the lighter member of the two should make the cut, and the heavier member should act as the safetyman. Communications are best carried out nonverbally. (See “Saw Operations: The ‘Tap’ Method” by Michael Ciampo, The Truck Company, Fire Engineering, April 2002.)
A power saw can bind or kick back, causing the user to lose his balance, especially if the roof is too steep to walk on. For this reason, the use of a chain saw or an ax is favored over a circular power saw by some departments when operating on steeply peaked roofs. Unfortunately, it takes a long time to make an adequate-size hole in plywood with an ax, though it can be quite effective on older, preplywood construction where furring strips were used to span the rafters.
Should you lose your balance and fall, try to lay out spread eagle. The friction created may slow your slide and give you a chance to grab a hold of something. A pickhead ax can stop a slide. If time allows, drive the point of the ax into the roof and hold on with both hands. If you should fall on your back, lie flat and press the soles of your boots onto the roof surface with your knees bent. This, again, should create friction and slow or stop your descent. As a last resort, the gutter can be used as a stopping point.
As with any roof operation, a second way off at the opposite end of the roof should be provided. A ladder positioned on each side of the roof and one placed at the far end from the fire would provide even better options for exiting the roof if conditions become untenable. However, placing two aerials is oftentimes not possible at fires in single-family homes spaced away from the street. In these cases, a 35-foot ground ladder should be placed at the opposing end from the aerial. On reaching the roof, members should take a look around to locate alternative exit routes. Perhaps there is a flat area, a setback, a dormer, or a porch roof that can provide another way off in a pinch.
In some cases, the hole must be made at the far end of the roof from the primary access point. In these instances, correctly positioning the roof ladder can take some forethought and is always a two-person job. One firefighter moves the ladder, and the other moves the saw and tools. The best method for reaching the point of operation is to straddle the ridge and slide along it, pushing the roof ladder in front as you go. Avoid leaning on chimneys or vent pipes, which can give way. Once you reach the point of operation, orient the roof ladder so that your cut will be on the far side of the ladder from your access point. This may require that the ladder be placed on the opposite side of the ridge than originally intended. Once placed, set the hooks into the ridge, test it, and step onto it.
MAKING THE CUT
One thing that can ruin your day is to reach the peak of the roof and find that the saw won’t start. With most saws, the best approach is to start the saw at the beginning of the duty tour and let it run until it’s warmed up. Some members rev the saw up immediately before shutting it down. This is not a good practice. Instead, let it idle for a minute, then shut it off. Revving the saw before shutting it off only fills the combustion chamber, making it harder to start. If the saw has been fueled, started, and run properly at the beginning of the tour, there should be no problem starting it on the roof.
Whenever operating on a peaked roof, members should bend their knees, keep a low center of gravity, and lean into the roof, using all fours whenever feasible. Cutting a hole alongside of a roof ladder obliges the firefighter using the saw to lean outboard and reach laterally. However, the member using the saw must keep his weight balanced over the ladder and avoid overextention. Lean your weight into the ladder and the roof.
Because of the lateral extension, cutting a large hole in a peaked roof is often a two-step process. For the greatest ventilation effect, place the hole at the ridge on the leeward (downwind) side of the roof. The higher, the better, and once the initial hole is opened, the roof ladder can be moved back a few feet in the path of travel so that a second cut can be made to enlarge it if conditions permit. Generally, the size of the first opening is limited to a hole 2 feet by 3 feet and enlarged from there.
An effective cut from a roof ladder is a narrow rectangular cut commonly referred to as a coffin cut. The coffin cut is made alongside the roof ladder and limits the amount of lateral extension for the firefighter operating the saw. The vertical cuts are made parallel to the rafters approximately 30 inches apart so that the cut spans only one joist in the center. This allows the cut section to be hinged on the center rafter for easier removal. Once the cut is complete, the side closest to the edge of the roof ladder can be pushed down while the far side can be pulled up. The location of the joists is often visible if you look closely, because of settling of the shingles between joists.
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If the cut is made from a tower ladder, the saw operator should use a safety harness held firmly by the safetyman. When the saw has been started and it is time to make the cut, one foot can be placed on the roof while the other is kept in the bucket. A triangular opening is made with the initial cut parallel to the ridge. The member using the saw should not try to overextend. Once the cut has been opened and the ceiling pushed down, it can be enlarged by moving the bucket.
If no smoke or fire pushes out, probe the hole with the 10-foot hook, and push down any obstructions. Remember that when a hole is made at the ridge, an eight-foot hook may not be long enough for the job. If the hole was put in the right place, a good volume of smoke and flame is likely to discharge. This signals that it is time to retrace your steps and get off the roof. Water and steam coming through the hole indicate the engine company is making progress below. If all you see is a flame plume, then you have a free-burning fire below you and it’s time to take the tools and depart. Conditions can deteriorate rapidly, and it takes time for each member to climb down with the equipment. Once the hole is opened, departure from the roof should begin immediately and with a second exit option in mind should conditions change rapidly.
When working from a roof ladder, do not place the hole in your path of egress. This mistake is easier to make than you might think. Most members are right handed and have a natural tendency to work off the right side of the roof ladder. However, if they came from the right side of the roof, their means of egress could be cut off once the hole is opened. Given that the roof ladder is often chosen because an aerial ladder could not be placed to the roof, this can leave the crew in a precarious position. There are a couple of options that can preclude this. One option is to place the roof ladder on the other side of the ridge and cut there, provided that wind is not a factor. This places the cut on the far end of the ladder and out of your path of egress. Another option is to make the saw cuts from the roof ladder but to not open the hole until you move your ladder and equipment to the retreat side of the opening.
A final remedy is to be able to “switch hit” and cut from both the left- and right-hand sides of the ladder. This skill is best mastered during training drills, where proficiency can be gained with the saw. Many fire training centers have peaked roof simulators for practicing roof-cutting techniques under safe conditions. When conducting training sessions, it is important to treat the simulator as if it were an actual roof and not take any shortcuts.
The experience gained during hands-on training sessions can make peaked roof operations safer and allow members to develop confidence and facility on sloped surfaces. The first time a firefighter operates a saw on a peaked roof should be at the training center’s roof simulator, not at an actual fire.
Venting peaked roofs is an essential part of aggressive firefighting operations that is not without risks. Going above the fire on an inclined surface requires mental alertness to conditions, good balance, and physical agility. The tactical uses of aerials, elevating platforms, or roof ladders are time-tested methods that can make the job safer. It is, therefore, important to train with them so that firefighters become familiar with their use.
DOUG LEIHBACHER is a 26-year veteran of the fire service and a captain in the Yonkers (NY) Fire Department. He has an associate’s degree in fire protection technology and a bachelor’s degree in education. He has served as senior instructor at the Yonkers Fire Department Probationary Firefighter Training School. He is a New York State certified fire instructor and municipal training officer and has been a classroom and a hands-on instructor at FDIC as well as a contributing author to Fire Engineering for more than 10 years.
