Photos by author.
IT’S IN THE ATTIC…!
STRATEGY & TACTICS
Train and drill on the strategies and tactics necessary to attack this unique fire compartment.
THE INCIDENT commander confronted by a residential attic fire faces a difficult and demanding fire attack situation that tests his fire scene management skills. The attic fire is unique. The fire problem it presents is different than in any other residential area. What makes it unique are its characteristics as a fire compartment.
THE ATTIC AS A FIRE COMPARTMENT
The concept of the “Tetrahedron of Fire” states that the physical-chemical phenomenon we call the diffusion flamecombustion process—fire —is in fact the re-action of a fuel, an oxider, and temperature in an environment that allows unlimited and uninhibited chemical reactions.
In this concept, all fires represent a dynamic physical-chemical interaction not only between the four components of the tetrahedron but, most important, with the structural components of the fire compartment. The characteristics of the fire compartment—its fuel load and arrangement, compartment volume, and ventilation opportunities—all have an effect on the nature of the fire and how personnel will fight it. As the attic fire differs from other residential firesituations, so must the incident commander develop a fire attack that fulfills the demands of the attic fire situation.
Let’s consider several features of the attic fire compartment that affect the diffusion flame combustion process.
ATTIC FUEL LOAD
Dead load. In most fire situations the incident commander must regard the roof and its rafter assembly, portions of bearing walls, and top-floor ceiling rafters of the structure as exposed fuel sources. As fire consumes the structural members, it rapidly affects the structure’s ability to bear its own load as well as retard fire growth. In essence, the fire is consuming the materials that keep the building in its present shape and form. Roof failure then becomes an immediate consideration, as the fire has access to the roof support system and roof sheathing material.
Furthermore, the fire may attack the support members of the top-floor ceiling, cause its failure, and extend into the top floor itself. The ceiling is designed to keep a fire in the top floor and out of the attic but not the reverse.
Live load. Storage space is at a premium in most homes. It stands to reason that the attic would be utilized as a storage area by the occupants. You may find almost anything stored there. If the occupant can carry it, it may wind up in the attic.
Synthetic materials such as bedding, upholstery, and plastics will affect the amount of heat that is released and therefore, the time to flashover within the attic. These materials not only contribute significantly to the fire load and its spread but can severely hamper operations by limiting mobility of the firefighters and stream attack. In addition, small but heavy objects may cause local collapse as they rain down on unsuspecting firefighters operating on the top floor.
THE ATTIC AND THE ROOF
The attic is defined as the space between the top-floor ceiling and the underside of the roof. The roof forms the top or the upper limits of the attic. The roof structure, in addition to representing a significant source of fuel, will exert a tremendous influence on the development of the attic fire and hence the effectiveness of the fire control efforts. Since the products of combustion tend to rise, the roof structure will prevent vertical ventilation of the attic fire. Furthermore, if the roof structure involves a sloping roof of the hip. gable, or gambrel design, the roof may also severely inhibit horizontal ventilation as well. In some cases, as in the hip roof design with the roof sloping upward from all four walls, the roof may occupy the top, the front, the left, and the right of the fire and may therefore, through its restriction of ventilation opportunities, become the dominant factor in the fire control effort.
The restricted volume over which the fire can diffuse combustion products makes vertical ventilation imperative.
RESTRICTED VOLUME OF THE ATTIC
Attics, under most circumstances, do not constitute living space and are therefore designed to be small structural compartments. The volume of space over which the fire can diffuse the products of combustion is restricted. As the fire grows, it continues to consume oxygen and produce heat and other products of combustion and will significantly increase the pressure within the attic. Therefore, any opening made by the attack team in their effort to enter the attic may produce a tremendous outrush of smoke, heat, flame and other fire gases, a backdraft, or a smoke explosion, all of which will increase the risk of injury to the attack team and the possibilities of fire extension. There is a dire need of vertical ventilation. Fire in this area has the ability to generate enormous quantities of confined heat, form unlimited chemical reactions, and continue to grow on abundant exposed fuel. It can rapidly cause deterioration of roof and ceiling support members.
THE ATTIC FIRE ATTACK
The characteristics of the attic make the attic fire suppression effort radically different from other residential fire attack situations.
It is almost impossible to implement an attack on the attic fire immediately upon arrival. The area for attack team maneuverability is severely limited, and most important, there may not be any alternate means of egress for the attack team should an unexpected fire event — flashover, smoke explosion, or backdraft—occur.
Initiating the attack
Consider what the attack team members must do in order to initiate an attack: First, they must stretch the attack line from the apparatus to the fire building, then advance the line upward through the structure to the top floor. They must then locate the pathway to the attic, which may involve searching for the attic stairway, the attic scuttle hole, or, as a last resort, the opening of the top-floor ceiling. These activities take time, and all the while the fire is growing in size and intensity, expanding its hold over the attic and perhaps the structure itself and further complicating the fire attack effort.
Maneuverability
Remember that the attic is by definition a rather small structural compartment. The room for maneuvering is limited because of height. The sloping roof common to residential construction aggravates the problem, with space diminishing as one travels away from the centerline of the attic. Furthermore, many attics lack floors or have only partial floors, exposing the attack team to the hazards of falling between the top-floor ceiling joists. Members of the attack team may literally fall out of the attic to the floor below and sustain serious injury.
Alternate egress
Unfortunately, the attic fire situation is much like that of the cellar: The way that you enter is the only way out. In most cases the attic does not have any windows or doors, which firefighters have historically regarded as alternative means of egress in other fire attack situations. Attics were not designed as living spaces and therefore do not need doors and windows. This is a serious situation for the attack team. Both the attack team and the incident commander must take extreme pains to preserve the integrity of the interior path to the attic.
TACTICAL ALTERNATIVES
Unless the incident commander is willing to concede the involved structure, he must pursue an offensive fire strategy to combat the fire in the attic. Most attics do not allow attack streams to reach the fire from the outside, eliminating the defensive tactic of knocking down the fire before entering. In the barest terms, the incident commander must structure a fire attack effort that goes after the fire. He cannot employ, if any degree of success is to be expected, an attack effort that only confronts the fire where it appears—the windows, vents, or eaves.
To effect the offensive strategy, the incident commander has three tactical alternatives: (1) attack from the top floor into the attic by removing the topfloor ceiling, (2) attack from the roof down into the attic by removing portions of the roof, and (3) attack by the advancement of one or more attack lines directly into the attic from outside.
Since each tactical alternative will produce relative advantages and disadvantages and each attic fire situation will be different, the incident commander will have to determine which of the three is the most appropriate for the fire situation at hand. To that end, he must consider, in addition to other more generalized size-up factors, the roof type of the involved structure, since it will directly influence ventilation possibilities. Additional considerations include the volume of the attic and, hence, the amount of fuel that can be stored within the attic, the potential impact of the fire on the structural integrity of the roof, and the room for attack team maneuverability within the attic.
Attacking from the top floor
Attacking from the top floor through the ceiling is one option in most residential attic fire situations. It can be accomplished by removing the ceiling and operating the attack lines into the attic through the openings. This tactic is advantageous in that the attack team does not have to enter the attic, thereby rendering the considerations of attack team maneuvering room and alternate means of egress from the atttic irrelevant. This tactic is most applicable to the flat, shed, mansard, and hip roof designs, which, because of their limited attic height, will place the majority of the attic within reach of the attack line once the top-floor ceiling has been removed.
The attack through the top-floor ceiling is not without its disadvantages. First, the tactic is time-consuming, is physically exhausting for the attack team, and exposes the attic as well as the top floor to considerable fire control damage. Additionally, the fire attack must still be coordinated with ventilation efforts; without ventilation the products of combustion, as a result of the energy generated by the attic fire, will band downward into the top-floor area. The occurrence of flashover and fire extension within the top floor must be regarded as a real possibility. Also, falling pieces of ceiling material will increase the risk of firefighter injury. The contents stored within the attic, ranging from bowling balls to baby carriages, could fall on the operating personnel.
The incident commander should keep in mind that the attic flooring and contents may obstruct the penetration of the stream into the attic, and the effectiveness of the attack stream may be negatively influenced by the increased height of gable and gambrel roof designs.
Attacking from the roof
Fire attack down from the roof into the attic is particularly useful in structures with the shed or flat roof designs or those with high top-floor ceilings. This tactic, requiring extensive roof opening, eliminates the need for the attack team to operate in the attic as well as all of the concomitant risks. Since the opening-up work will be done on the exterior of the stucture, the attack team can use power tools, reducing the time and physical exertion required. Firefighters will be working on the roof with their work directly in front of them—not over their heads as in the first tactical alternative. Hopefully, they will be operating under visibility conditions better than those that might be expected on the top floor. Most important, this alternative affords the incident commander the opportunity to redirect the attack effort: If insertion of the attack line into the large roof openings is not immediately successful, the vertical ventilation that is attained may induce an upward draft, retarding horizontal fire extension and enhancing the advance of a line from the top floor into the attic.
On the negative side, this tactic may not be applicable to the mansard, hip, gable, and gambrel roof designs as the roof team will not be able to work near the edges or on the lower slopes to make the necessary openings. Furthermore, extensive and time-consuming roof operations will be required, exposing firefighters to risk of injury from roof failure. The prolonged set-up time that this tactic entails concern is another concern: As the attack effort is organized and the needed resources transported to the roof, the worsening fire conditions will further weaken the roof structure that must support the weight of the attack. The incident commander who employs this tactic must be cognizant of the fact that tactical positions above a fire are very dangerous and subject to rapid deterioration, necessitating not only an alternative attack plan but also a structural evacuation plan. Finally, since the operation of an attack line down into the fire from above will complicate the ventilation problem, the incident commander must evaluate the potential for fire extension within the fire building and to adjacent structures.
Attacking from within the attic
Because it supports the extension of the primary search, this tactic is particularly well-suited for use within the gable and gambrel roof designs. Ever-cognizant that the gable and gambrel roof designs offer sufficient height for the attic to be used as a living area, the incident commander must, unless advised otherwise by the property owner and/or occupants, routinely extend the primary search into such attics. Since the attack line can be advanced into the fire area, a more direct attack on the fire will result, and the attack team will be able to complete the extinguishment process after fire knockdown has been achieved. When coordinated with effective vertical and then horizontal ventilation, this tactic is most effective. It affords the attack team the opportunity of advancing on the fire behind the ventilation efforts and sweeping the products of combustion up and out of the attic.
Although advancing the attack line directly into the attic is the only tactic that supports the primary search, it is not without its disadvantages. On the down side, the incident commander must consider that the pathway to the attic may not be obvious to the attack team. Second, attack within the attic exposes the attack team not only to risks encountered in the more “conventional” residential fire attack situation but also those risks associated with lack of maneuverability in the attic and the absence of alternative means of egress. The advancement must be coordinated with horizontal and vertical ventilation efforts.
Furthermore, if the attic stairway enters through the middle of the attic—as most do to maximize headroom —the attack effort may require a second backup line, each attacking outward from the top of the stairway. Moreover, with the limited headroom that is characteristic of attics with the hip, mansard, flat, and shed roof types, the value of this tactic is questionable.
A major disadvantage is the temptation to advance the attack line into the attic through a window. Whether the line is advanced off of a ladder or off of an attached roof such as a front or rear porch, such a tactic does not support the primary search; nullifies ventilation, which may contribute to horizontal fire extension and increase the risks to which the interior sector must be exposed; and sets up the situation for opposing streams.
The attic fire represents a dynamic and ever-changing situation. If the fire is not getting smaller, it is getting bigger, and if it is getting bigger, then the situation is deteriorating rapidly.
The incident commander must realize that the attic fire and, hence, the attic fire attack, is a radical departure from other residential fire attack situations. The time it takes to make a size-up and choose and implement a tactical alternative, and then for the tactics to have a positive effect on the fire control situation, is extensive. This extended time interval will give the fire the opportunity for continued growth in terms of size, intensity, and deterioration of structural stability of the roof assembly and increase collapse probability.
The incident commander must be aware of the indicators of an ineffective fire attack—such as reports from the interior officer, the continued observation of large volumes of fire and smoke, and/or changes to the structure—and he must select another tactical alternative to mount a fire attack that is in tune with the demands of the fire situation at hand.
