“BREAD AND BUTTER” OPERATIONS: STORE FIRES, PART 4—ROOF OPERATIONS
With staffing problems affecting almost all fire departments across the country, obtaining maximum use of personnel on the fireground becomes extremely important. For fires in stores, members assigned to perform truck company functions will be in demand. The incident commander must be able to foresee the need to call for help early to bring the fire under control rapidly.
Truck company firefighters usually are split to cover two separate areas of responsibility. The inside team normally is responsible for forcing entry into the store, conducting searches for both life and fire location, performing horizontal ventilation, and assisting the engine company. The outside or above team’s duties vary with the ty pe of building in which the fire is located.
For fires in “mom-and-pop”-type stores, the above team is responsible first for making sure that the inside team does not need assistance and then for the floor above the fire. As part of their duties, aboveteam members should raise portable ladders to the second floor for access and egress. Once they are operating on the floor above, their duties include searching for trapped occupants as well as looking for extending fire. They should remove baseboards and open up walls to help expose hidden fire. If they find fire extending into the second floor, above-team members immediately must notify the IC and request a handline stretched to their position. If the fire gains a foothold on the floor above, the IC must consider the possibility that the fire also will extend to the attic or cockloft-additional personnel wiil be needed. If no assistance is available, the IC may have to reassign members of the inside team.
When fires in taxpayers extend into the cockloft, preventing complete involvement of the entire structure is an extremely difficult task. Proper, early ventilation is the greatest tool at our disposal in the fight to save the building. Properly performed ventilation removes smoke and heat from the building while improving interior conditions for the advancing engine companies. It also limits fire spread by preventing mushrooming and by giving the superheated gases a controlled means of escape out of the building.
CONSTRUCTION FEATURES
To properly perform ventilation, an understanding of the construction techniques used and the building features you will encounter is essential. You will encounter many different types of roofs, and each will have a different operational plan.
Most of the older roofs have wood joists covered with tongue-andgroove boards, plywood, or both (plywood frequently is used to replace boards damaged by the elements or fire). On top of this deck, you will find tar paper, a combustible waterproofing material. Occasionally, sheets of tin also are used on the roof as additional protection from the elements. The tar paper may be several layers thick, as the roof may have been resurfaced to prevent leaks.
Newer strip stores may have roofs constructed of steel bar joist trusses supporting roof decks made of gypsum planks, metal Q-decking, precast concrete planks, or even wooden deck members. Roof surfacing materials will vary depending on the roof deck.
HOOF OPERATIONS
Another type of roof you may encounter is an inverted roof. Used to control water drainage in buildings with a large roof area, its joists are located at ceiling level, and 2 x 4s of varying lengths are attached to the beams and extended upward to support a gridwork to which the roof decking is nailed. By varying the length of the 2 x 4s, the roof can be sloped in whatever direction is advantageous for drainage.
Recognizing these roofs during operations with a smoke condition is extremely difficult. Inverted roofs have a springy feeling even without a tire condition underneath them. In most cases, roof slopes, if present, run from front to rear. This means that the cockloft has the greatest depth at the front of the store. If fire enters the cockloft at the front of the store rather than the rear, the fire extension problem will not be as severe —fire does not spread from a high point to a low point as rapidly. Older taxpayer roofs may have no pitch at all.
(Photos by author.)
ROOF ACCESS AND OPENING
Access to the roof is the first problem to overcome on arrival. The easiest and quickest way to the roof is by portable ladder. By using a 20-foot straight or short extension ladder, one member can transport and raise the first ladder to the roof level. Raise portable ladders to all available sides of a taxpayer; place a minimum of two at the front of the building, preferably at opposite ends. Position aerial apparatus, especially platforms, for use both for roof access and for possible master stream operations.
Tool assignments for roof operations vary’ from department to department, but always take the following: axe, halligans, power saw(s), and pike poles. Use the halligans to help pry open scuttle covers and pull ventilation holes. Use the pike poles to help pull cut holes and push down ceilings after opening the hole. Use power saws to make the cuts and the axe for striking and in case the saw’ breaks down.
The roof may have any of the following features:
- Skylights may be present or may have been covered for security rea-
- sons. Materials used to cover them include plywood, steel, and sometimes only tar paper. Do not stand on these covered openings in an effort to “open” them up.
- • Scuttle covers, if present, also are
- frequently sealed shut for security reasons. They might be nailed or chained shut from the inside.
- • Ventilators of all shapes and sizes may be present. Removing them provides some ventilation for the store or
- cockloft, depending on their original function.
- • Roof-mounted air conditioners or large billboards or signs should be noted; advise the IC of their presence immediately. The added weight of these units may cause early collapse of the roof or supporting walls. Other information to relay from the roof to the IC includes overall size of the taxpayer, building shape, location of fire, description of visible fire or smoke conditions, and any exposures to which the fire may extend.
Initial roof operations at a working fire in a taxpayer should include removing covers on all natural openings in the fire area. Open scuttles and skylights over the main fire area immediately. Then open the returns (the covered area that separates the cockloft from the scuttle or skylight opening) to check for fire in the cockloft. An exception to this would be if the skylights are to be used as a boundary for a trenching operation. In this case, leave the returns in place.
Remove roof ventilators if smoke is issuing from them. Check for fire extension into the cockloft early and often.
ROOF OPERATIONS
If you discover fire in the cockloft or conditions indicate the need for additional ventilation, cut holes in the roof. The locations of the cuts would be based on fire location, wind conditions, and available personnel and tools. Make cuts with the wind at your back so that the fire does not drive you off the roof as it vents out of the opening. When cutting holes for additional ventilation, make them large enough so the superheated gases and smoke rapidly exit the building. A hole eight by eight feet is ideal but hard to cut and harder to pull. It is easier to cut the hole in fourby fourfoot or smaller, more manageable, sections and extend it as needed.
Do not pull the hole until you have made all the cuts, l ire venting out of a partially cut hole might prevent you from finishing the rest of the needed cuts. Use two saws immediately, when available, to provide the needed cuts as rapidly as possible. This requires at least four members and (because of the two saws) an officer to supervise the operation. Since this is more personnel than some departments have to spare on the fireground, a one-saw operation is possible. Once you cut and pull the hole, you must push down the ceilings beneath if conditions permit personnel to get close to the hole.
If the roof requires cutting, cut early while it is at its strongest. Monitor conditions constantly, as roof supports and decking will burn away or become weakened as the fire continues to burn. Expect early collapse of the roof assembly under heavy fire conditions. In most cases, roofs fail section by section —not in one piece.
In addition to ventilation holes, cut additional examination holes as soon as practical. Use these holes to check for fire extension into other areas and to determine the need for additional ventilation openings.
Another type of roof operation is the trench cut. Although it is not practical to use when fire already has control over a large portion of the taxpayer or when the building is deep (thereby requiring a very large, timeconsuming cut), it is practical in some instances. A trench cut is a strip cut at least three feet wide made between two distinct points (exterior walls, bulkheads, fire walls) that act as a fire break. It is not a ventilation opening. It cannot be used unless a main ventilation hole already has been cut over the main body of fire. If you cut and pull a trench without a main vent hole, the trench will become the main vent hole as fire is drawn to this opening. It is a defensive opening used to limit the fire extension to a particular area. If only one saw or limited personnel are available, do not consider using a trench cut.
Newer roofs—those constructed with steel bar joists or even lightweight truss assemblies—prohibit any roof operations if the fire has entered or is impinging on the truss loft. Even with favorable fire conditions, operations may be limited by the materials used in the construction of the roof assembly. Gypsum planks and precast concrete panels render power saws useless. Q-decking under a tar and gravel roof surface will knock off most of the teeth on a circular saw blade, rendering it useless or making cutting painstakingly slow. Many times operations on newer roofs are reduced to opening all of the natural openings (skylights and scuttles) and then leaving the roof.
Operating on the roof of a burning store is extremely dangerous. The heavy smoke from a cockloft fire makes visibility on the roof near zero. Fire burning unchecked beneath the operating forces weakens the roof deck from which they are operating. The IC must weigh the risk vs. the expected gain and make decisions based on the safety of the firefighting forces.
Fires in taxpayers require a considerable number of personnel to mount a proper attack. Consider the tactics described here the basic requirements for beginning an operation. As more personnel become available, you also must address other fireground functions. These include covering all exposures (adjacent stores within the taxpayer as well as any adjacent buildings) with sufficient staffing for hoselines and truck company operations, performing horizontal ventilation and forcible entry of the rear of the stores, gaining entry to all basement areas to check for extension and control of all utilities, and relieving first-arriving companies.*
