Fireground Size-Up: Row Frames

By Michael A. Terpak

The row frame, as the name implies, is a row of attached wooden buildings that can vary in height from two to four stories. Each individual building can range in width from 20 to 30 feet and in depth from 40 to 60 feet. The number of attached buildings in the row can range from three or four to as many as a dozen or more, all with a common cockloft, a common cornice, and—in some cases—a common basement.

Let’s look at the 15-point size-up represented by the acronym “COAL TWAS WEALTHS” for row frames.

CONSTRUCTION

Row frames’ construction and inherent building features present some of the greatest challenges for the fire department. They are Type 5/wood-frame construction, encompassing balloon and braced frame designs. With balloon-frame design, fire officers must anticipate how fire can extend through the buildings’ interior and exterior wall channels with no restrictions.

With the braced frame design, the concern is the connection points of the framing system: There is a framework of vertical timbers called “posts.” The posts are positioned at each of the four corners of the structure as well as at intervals in between and vary in size from 4 2 4 to 4 2 6 to 6 2 6. There also are horizontal cross-members called “girts”—wooden structural members of varying sizes fastened to the posts through a mortise and tenon connection at each floor level. The girts, which can act as vertical fire stops at each floor level, are cut down at their ends to form a tenon, designed to fit snugly into a mortise slot cut into the vertical post. The combination of posts, girts, and studs make up the wooden framing system.

Although the design contains significant-size lumber, the mortise and tenon connection becomes a critical concern: With a large structural member shaved down at the connection point into a tenon often no bigger than half of its original dimension, the integrity of the connection point after a hundred-plus years of use comes into question.


1 Photos by author unless otherwise noted.

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Another unique and important construction feature of the row frame that you also must identify is the use of brick nogging in the load bearing walls (also known as division or party walls), which separate the individual buildings within the row (see photo 1). Brick nogging is individual bricks and mortar placed in the division wall’s vertical stud channels for their entire height to give strength to the wall, prevent fire from traveling through the wall into the adjoining building, and give the wall some insulating value. However, brick nogging also results in an increased dead load in the load bearing walls. There also is a possibility that the bricks were placed in the stud channels with no mortar bond.

One of my first experiences with brick nogging as a young firefighter was when I was overhauling a burned-out room in a row frame. We opened the plaster and lath of one of the party walls, and a stud channel full of bricks emptied into the room where we were working. The bricks were being held up by gravity and their enclosure within the space. There should be no doubt in anyone’s mind that this type of wall design can greatly affect the integrity of the building.

OCCUPANCY

Since the row frame is classified as a residential occupancy, the number of apartments and people in the building is a concern. The majority of row frames feature railroad flat-type apartments with two apartments per floor off an unenclosed interior stairway. The number of people who can occupy an individual apartment varies. Although these apartments are normally considered to be small, never underestimate the number of people you may encounter. Also look for the possibility of an illegal apartment in the basement.

APPARATUS AND STAFFING

Undoubtedly, any fire in a row of attached structures requires an early commitment of resources and equipment. If a fire is reported in a row frame, you must give significant consideration to apparatus response, placement, and operation.

Engine company considerations. The first-due engine company should leave a sufficient scrub area for the first-arriving ladder company to operate and should select and stretch a hoseline based on speed and mobility. Because of the life hazard, possible apartment layout, square footage, and high probability of fire extension, a well-placed hoseline with a sufficient water flow is a must. The hoseline of choice for most departments for a row frame fire is the 13/4- or two-inch hoseline. Anything less will often be insufficient. Anything more than a two-inch hoseline will lack the speed and mobility to quickly be placed in operation.

Ladder company considerations. Because of the significant fire spread problem at a row-frame fire, the front of the building belongs to the ladder company for a number of reasons: accessing the building’s roof; having close accessibility for additional ladders, tools, and equipment; and enhancing the use of the apparatus at a well-involved fire. In cities that use tower ladders, the latter is especially true. Having a well-placed tower ladder in front of the fire building allows that apparatus’s scrub area to reach as many as three or more buildings in the row. With a well-involved top-floor/cockloft fire, the tower ladder’s effectiveness quickly becomes evident (see photo 2).


2. Photo by Alison Ashley.

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In addition to the ladder company duties of entry and search, ventilation and channeling of the fire become critical considerations. Fires in row frames are notorious for their rapid spread through the common cockloft. When a fire involves the top floor and/or cockloft of a building of this type, chief officers must be prepared to assign resources for the necessary ventilation tasks. Members assigned to this task must be well disciplined and experienced in roof operations.

The following are roof operations for row frames:

  • Cutting, pulling, pushing, and enlarging the primary vent hole over the main body of fire. With the rapid movement of the fire expected throughout the cockloft, the objective of the primary ventilation hole is to create a thermal updraft and slow the fire’s horizontal spread. The larger the hole, the better.
  • When fire is threatening to spread throughout the cockloft to attached structures, cut and pull a “trench.”

The following are trench-cutting operations for row frames:

  • Ensure that the primary ventilation hole over the main body of fire has been established before cutting the trench. This is critical. Trenching is a defensive operation. The primary vent hole is the offensive cut.
  • Cut inspection holes ahead of the primary vent hole to help you determine the need for the trench. Consider wind speed and direction.
  • Open up the return walls within the scuttle openings of attached structures to determine fire spread within the cockloft (see photo 3).
  • Place the trench at least 25 feet from the primary ventilation hole. This will allow time to cut and pull the trench.


3.

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  • Make the trench three to four feet wide from the front to rear walls of the building.
  • Precut the trench every four feet along its length to assist with the speed when pulling.
  • Cut, pull, and push the primary ventilation hole before pulling the trench, or you will draw the main body of fire toward your trench. Remember, trenching is a defensive operation (see Figure 1).

LIFE HAZARD


Figure 1

When operating in the interior of the building, a number of concerns will quickly present themselves because of the building’s ability to quickly become consumed by fire. With the building ranging in height from two to four stories, the presence of an unenclosed interior stair is a key concern. If a fire were to originate on a lower level, gaining control of this vertical artery would be a major objective early in the fight. I say this not only for the building’s occupants but also for the protection of those firefighters attempting searches on the floors above.

A less obvious but serious threat to firefighters is fire involvement of the concealed spaces and voids. As fire burrows its way into the walls, ceilings, and cockloft, gases can build to the point where they can starve themselves of the necessary air to support combustion. This becomes a key factor in how and when firefighters open up concealed spaces and voids in an attempt to extinguish fire.

When operating in the exterior of the building, the concern is structural collapse. The building’s party walls, brick nogging, age, settling, and fire involvement will affect structural stability. If each building relies on its neighbor for support, any missing building or buildings in the row from a previous fire or demolition could cause the “new” end buildings to become structurally unstable. Although a vacant lot next to an involved building may seem an inviting place for exterior forces to set up, chances are that if the building falls it will fall to the unsupported side.

TERRAIN

Any concerns regarding building setbacks or grade level changes will be address-specific. Buildings set back from the street may require the engine company officer to reconsider the type of stretch. For long stretches, factor in the water supply needed, the friction loss of the hoseline, and the number of people required to get the line to its intended location. Grade level changes with any building—for example, a building that is two stories in the front and four stories in the rear—will greatly affect fireground management if not planned for.

WATER SUPPLY


Figure 2

The water supply requirements will quickly become evident after fire begins to spread down the row. Quick, large, and sustained water flows are necessary to mount an effective and efficient attack on the fire building and its attached exposures. With the combustibility of the structures and the inherent building features that will allow fire spread to adjoining exposures, employ a number of attack or operating pumpers, each supplied by a supply pumper, to ensure quick, sustained, and efficient flows (see Figure 2).

AUXILIARY APPLIANCES AND AIDS

If any equipment is found in the building, it will be in the form of smoke detection. Although code requirements vary from state to state, during the early 1980s, many urban areas saw a dramatic reduction in the number of fire deaths each year after codes mandated smoke detectors in residential buildings. From personal experience during routine responses to these buildings, however, I know that previously installed detectors generally are not maintained—often the battery and even the detector are removed. When you see such a situation, it is important to correct the danger.

STREET CONDITIONS

Look at possible difficulties concerning street width and traffic flow where these buildings exist in your jurisdiction. Narrow, one-way streets will affect apparatus movement, key apparatus placement, and your ability to quickly control the fire. Do not ignore areas in which these difficulties exist.

WEATHER

Wind speed and direction are important considerations when fire has taken possession of the cockloft area. Cocklofts can be as small as 18 inches or as large as six feet in height extending over all the buildings in the row. Fires that involve the top floor and cockloft area of a row frame will require a significant commitment of firefighters to the top floor of the fire building, a primary ventilation hole over the main fire area, and early assignments to both exposure buildings to pull ceilings and deploy additional hoselines. As firefighters open the ventilation hole and continue to enlarge it, significant winds that are moving across the roof deck can affect the thermal updraft of the opening and drive fire throughout the cockloft. Even 10-mph winds can affect fire spread.

EXPOSURES

With numerous buildings attached in a row, anticipate early fire spread into the exposures. Shared light and air shafts are also common in row frames. They are built within the division/party wall that separates the attached buildings, so there is a possibility that a light and air shaft will serve both buildings.

Light and air shafts can be open or enclosed. Open shafts are surrounded by three sides of the attached buildings, with the fourth side open to the rear yard. Enclosed shafts are totally enclosed by both buildings and are not open to the rear yard. You must understand these shafts’ ability to allow fire to spread to the floors of the fire building and exposure building; thus, you must quickly identify their presence and assign the resources to halt the spread.

Usually, light and air shafts are not visible or open to the street side of the building. Thus, early identification becomes key. As you enter the street or approach the front of the building, you may see as an indication of their involvement what appears to be a fixed column of smoke or fire coming from the roof area where the two buildings meet. If you do, don’t wait for confirmation of their existence; assign resources to the exposure building. Additionally, if you can see or your preincident information indicates that the depth of the fire building exceeds 40 feet, expect their presence.

Again, anticipate the early fire spread, and assign the resources. When you need to obtain specific information about the presence and possible involvement of light and air shafts, ask the firefighters assigned to the roof position or rear of the building.

As a firefighter assigned to the roof, once you access the roof, if you don’t see an air shaft, don’t assume there isn’t one. Often, the shafts are covered over with a thin piece of plywood and roofing material. This is primarily because the enclosed shaft design results in the collection of debris over the years. If present, an unsuspecting firefighter may step on this cover and fall three floors to death. If you see a fresh or more visible roof patch in this area, chances are there is a shaft below.

AREA

Area size-up considerations include the unusual or unexpected layout, accessibility, and living quarters. You can expect for the most part that most will have undergone little renovation, but always watch out for buildings beyond the 40-foot depth and illegal apartments in the basement areas.

LOCATION AND EXTENT OF FIRE

Remember that the row frame is an entirely combustible building capable of producing and concealing a large amount of fire. If the fire originates in the basement area, a number of concerns should quickly come to mind. First, the basement stair to the first floor will be old, flimsy, and unenclosed, allowing fire to attack the first floor hall and living area with little resistance. Second, the balloon framing will allow unrestricted fire travel. Third, there is the probability of a party wall between buildings where basement floor joists could share the same joist pocket, further allowing fire travel to an adjoining building.

For a fire on a lower level, expect unrestricted movement up the building’s interior staircase. Fires that exit to the exterior from any level will run the exterior siding with ease. If the siding is made of asphalt, fire development will be rapid. If fire on a lower level extends to a shared light and air shaft, expect fire spread to floors above in the fire building as well as to floors of the adjoining exposure. Fires that extend to or originate on the top floor and cockloft will be a little more challenging, with both exposure buildings requiring immediate attention.

TIME

As with any residential building, the life hazard will be high 24 hours a day, especially during the late night or early morning hours. In a fast-spreading fire in a row frame, usually occupants in the exposure buildings are unaware of the fire next door until it is on them. Evacuate adjoining exposures early.

HEIGHT

Building heights are well within reach of fire department ladders, so use them to gain access to the roof when accessibility is not a problem. You do not need them to remove building occupants. If such ladders are not immediately able to access the roof, use the scuttle ladders of nearby buildings. In larger attached frames, the building’s scuttle ladders are located at the top of the interior stairs. These small ladders will access the roof through a narrow opening. (Note that this is the area in the building that is often a collection point for the top-floor tenant’s junk. You can find anything from bicycles and mattresses to old furniture cluttering this area. Use caution when working in this area to avoid entanglement with these obstructions.)

Which scuttle ladder do you use? The fire’s location and extent will be the determining factors. If there is a significant fire on the top floor and cockloft, or if fire has spread to the air shaft of the adjoining exposure, then gaining access to the roof using the scuttle ladder of the adjoining exposure is not an option. With the inherent building characteristics of the row frame’s allowing for rapid fire spread in this area, an unsuspecting firefighter could be caught in the scuttle/top-floor area by an advancing fire while he attempts to force open the hatch. The hatches associated with any scuttle opening are often nailed shut or tarred over, causing a delay in opening the cover. Thus do not use the scuttle approach of the attached building when the fire is on the top floor. Put some distance between you and the fire. Move down two or three buildings to gain access to the roof area of the row frame if you choose the scuttle approach.

SPECIAL CONSIDERATIONS FOR CHIEF OFFICERS

The key to success at a fire in a row frame is anticipation. This, coupled with your education and experience, will become the basis of your decision making. Consider the following to reinforce your ability to think ahead.

  • On your arrival, obtain specific information about the fire’s location and extent. They should be automatic pieces of information voiced or radioed to you by the first-due engine or ladder company at every building fire.
  • Are there any light and air shafts between the buildings? If so, determine shaft involvement. Radio reports indicating that “it is heavy in the shaft” are not good enough. Reports have to be specific: “Is it heavy smoke or heavy fire?”
  • Determine if fire has entered the cockloft. If so, to what extent? Anytime fire is threatening the cockloft by any means, assign resources to the top floor of both exposures immediately.
  • With fire involvement of the top floor or cockloft, assign a significant workforce to handle the ventilation tasks associated with the primary ventilation hole and cutting and pulling a defensive trench.
  • Break the incident down into geographical areas as soon as possible. Establish Interior, Roof, B (Bravo), and D (Delta) divisions.

What are the conditions, accessibility, and life hazard in the rear of the buildings? Combustible siding will enhance the exterior fire spread not only to the building’s upper floors but also to attached exposures and exposures across rear yards. Additionally, building occupants may be forced to the windows in the rear. It is critical to get an early look at the rear of these buildings. If companies are assigned and going to work in the rear, establish Division C (Charlie).

If you are anticipating during your decision making, you will call for help early. If you don’t need the resources, you can always send them home; but if you wait until you actually need them to call them, it’s going to be too late.

MICHAEL A. TERPAK, a 27-year veteran of the fire service, is chief of the 2nd Battalion of the Jersey City (NJ) Fire Department, where he has been for 22 years. He has a bachelor’s degree in fire safety administration from the New Jersey City University, lectures frequently on fire/rescue service topics, and tutors firefighters and fire officers in preparing for promotional exams. He is the author of Fireground Size-Up (Fire Engineering, 2002).

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