Building Construction and Fire Dynamics – Are You Prepared for a Fire on Your Town’s Main Street?

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BY JOSEPH D. PRONESTI

Like many others in the service, my father was a firefighter for the same department for which I now proudly work. The one thing I still enjoy to this day is hearing the stories not only of fires past but how the city we both love used to have a huge downtown shopping district where you could buy anything you needed. Saghi’s Nut and Candy Shop, W.T. Grant, and The Men’s Shop are names that bring smiles and great shopping memories to the faces of countless older residents in my town. They were among the many businesses that graced the main street, called Broad Street.

These stores were housed in continuously attached ordinary construction Type III buildings designed for a mixed use: business on the ground floor and residential apartments on the upper floors. Many were built before the 20th century. The one thing that has changed is that the stores are now long gone. However, the buildings are still standing, and the occupied apartments are still above them.

The challenge today is how your department will handle the working fire in these structures, especially if you have not had much experience or training in these buildings. Failure to familiarize yourself and your fellow department members with the construction, renovations, and basic tactics needed to fight a fire in these structures will lead to a long drawn-out firefight that could possibly result in an embarrassing large vacant hole in your downtown or, worse, a firefighter line-of-duty death. Getting out of your station to familiarize your crews with these occupancies prior to the fire is a must.

Ordinary Construction

A general definition of ordinary construction is a building that features exterior masonry walls and combustible interior beams or trusses. Although it’s not the most often used building type today, Type III construction has been used a great deal for commercial buildings built in the past 100-plus years. Most of these buildings are two to four stories in height. Most of us on the job have heard the mantra, “Know your enemy; the building is your enemy.” To take it one step further, Deputy Chief Anthony Avillo of North Hudson (NJ) Regional Fire and Rescue states in his book Fireground Strategies that firefighters do not have any business in a building if they do not have a grasp of building construction and fire spread. Fires in continuous ordinary construction buildings will indeed affirm this wise statement. This article focuses on size-up and some common hazards you will find if you “shop your downtown” not for goods but for familiarization in case of fire.

Size-Up

One issue with these structures is that you cannot gain a 360˚ view immediately on arrival. When urbanized years ago, these structures, since they were on the main thoroughfare, may have been constructed with a narrow rear service alley for the delivery of goods. The fact that the alleys are continuous may make it difficult to get a full 360˚ view. It might be a good idea to think of these buildings as you would a “big box” store. It is paramount that command gets eyes in the rear as soon as possible. Most of the upper-floor apartment fire escapes will be there, and you may have easy access to upper floors for firefighters; or, you may find occupants needing assistance stranded on them. Many fire escapes are in need of repair and will definitely show effects of time and weather. The time to know the condition of these rear fire escapes is before the fire.

Just as we have been trained when learning how to attack a fire in a modern strip mall that getting ahead of the fire is the name of the game, the same is true with these structures, with one exception: The connected exposure building probably won’t be a one-story, lightweight constructed 25 × 100 hobby shop but a three-story Type III ordinary with tons of openings that allow for fire and smoke spread. Companies will be needed to open up, and multiple hoselines must be used for confinement of the fire. If you are in a small department, you must augment your resources as soon as you can. This means automatic aid or mutual aid—whatever your department uses—to get more help. Pulling up and thinking “I will give it 10 minutes before I call mutual aid; we can hit this” may turn into a report of smoke coming from the cockloft of a structure two buildings down very quickly.

Smell of Smoke

Many times, major fires in these structures begin as a smell of smoke. You can attribute this to the many openings common in Type III construction. A basement fire may be raging in a vacant building four or five buildings down from the address given by the original caller. Always handle these calls cautiously if you cannot trace the smell to the caller’s address; consider that the fire may be in another building on the same continuous block.

Renovations

Be nosy! When you see a large construction dumpster near an old building, be suspicious. Many times, the large timbers used in the original construction have been replaced with lightweight materials. Now the building is what could be called a “hybrid,” adding to the already large list of firefighter safety issues in these buildings.

Basements

These older structures more than likely will have a basement or a cellar. Access may be through a heavily fortified exterior door or a flimsy wooden trap door that is flush with the floorboards. Again, the time to know this is before a fire. Don’t be surprised to find that many of these structures have adjoined basements. They can be filled with just about anything, and a fire originating in the basement will be a tough fight. Command must anticipate extension to upper floors and to the exposures on either side.

Expect heavy security on exterior basement doors just as you would at the rear of a modern strip mall. Anticipate the added time you will spend forcing entry. Most stairs will be narrow and will be made of concrete or wood. Age may have also taken its toll on the stairs. They may be rotten or missing. Look out for conveyor belts and ramps; heavy smoke can obscure their presence. Since the structures were originally built as stores, many will have built-out showroom windows. Often, the floors of these windows are easy to breach and will supply quick access to the basement for ventilation or the rarely used Bresnan distributor nozzle.

If the terrain in the rear of the buildings is sloped, you will probably encounter doors that will lead directly to the basement level. This feature will make a basement fire attack much easier, but consider two important points: (1) As in a new strip mall, the rear most likely will be fortified, making forcible entry a key point; and (2) if you do mount your attack from the rear exterior basement entrance, make sure you coordinate with crews at the top of the interior basement stairs. Also, if the rear is a story higher because of the slope, ladder selection will become a factor. You may grab a 24-foot ladder from a truck parked in the front and take it to the rear alley only to find out that a 35-foot ladder is needed because of the slope. Don’t be surprised! This has happened more often than you think. Be ready ahead of time. Know the ladder placement and sizes needed.

Command as well as company officers must realize that when they are entering the first floor from the A side and are unsure of basement conditions, they may very well be advancing over a well-involved basement fire. One of the best lessons from the past on ordinary construction basement fires was learned in the fire on 23rd Street in Lower Manhattan on October 17, 1966, when a raging basement fire, coupled with unknown remodeling conditions, led to the deaths of 12 New York City firefighters. The victims of this tragedy ranked from firefighter to deputy chief. This incident is a “must study” if you consider yourself a proficient firefighter.

Subcellars

Many of these buildings may have a subcellar below the basement. It can be filled with countless items. Since many of these buildings were once in the “hub of the city,” they also served as fallout shelters in case of nuclear attack or bombing. If you see an old sign on the building indicating that it houses a fallout shelter, the presence of a subcellar is a real possibility. Get your members in the building and find its location and access points.

Parapets

Parapets are free standing walls above the roof line. Over the lives of ordinary Type III buildings, they are subjected to freezing/thawing, environmental conditions, and Father Time.

Upper Floors

As stated earlier, just because you have a vacant storefront doesn’t mean the entire building will be vacant. Responding firefighters could find anything from large remodeled studio apartments to single-room occupancies. The time to know the life hazard is before the fire, but many times this may be difficult even during company inspections or familiarizations. These buildings can change in an instant, which is another good reason to make sure you have help coming sooner rather than later when a fire breaks out.

A Word About Ceilings

A very common original feature in these buildings was tin ceilings. As the name implies, these ceilings were made of tin and were a very popular attractive design in the era in which most of these buildings were constructed. They also provided some fire stopping characteristics. Over time and to conserve energy, drop ceilings made their way into these structures. Their presence enhances the already present fire spread problem. When walking through these buildings prior to the fire, if you encounter drop ceilings and grids, try to see what’s above.

Remember also that these buildings usually will not have any type of central heating-ventilation-air-conditioning system. Ductwork and wiring most likely will be run between the original tin ceiling and the drop ceiling. During a fire, this situation can become an entanglement hazard for unsuspecting firefighters.

If you find drop ceilings on upper floors, try to see if apartment doors have transoms (a window that can be opened above a door to provide ventilation for the apartment). Usually, a drop ceiling will cover these transoms, and an apartment fire may breach them and run the concealed space in the hallway.

Upper-Floor Access

The main entrances to the residential occupancies often will be on the front of the structure, usually to the left or right of the first-floor store entrance. If this is the case, look for the basement stairs on the back side just as you would in a residential dwelling. Look for fire escapes in the rear. Although this information may not always be accurate because of renovations, a good rule of thumb is that one fire escape will serve two apartments per floor. Command must think about line placement to protect the stairs. Fire escapes could also provide line access to upper floors. Fire departments that do not train or have fires in these structures frequently will sometimes forget about this tactic. If these escapes are in decent shape (another reason to get out and check your buildings), the lengths needed to stretch will be shorter than having to go through the interior stairs. Interior stairs may also be much steeper than those in a residential dwelling. Before the fire, measure out with marked rope or a hoseline the amount of hose needed to reach the upper-floor apartments. Many departments get fixated on the crosslay or preconnect line, which is usually 150 or 200 feet long. Then, if the fire is in a mixed-use occupancy, they end up stretching short trying to access the apartments above. Don’t let this happen in your engine company.

Roof Operations

Many departments that do not regularly operate or train on roofs performing vertical ventilation will find that their crews are uncomfortable when fire is traveling quickly through a large, open cockloft of an ordinary constructed building. This lone tactic may determine whether the fire jumps to the adjoining exposures or is confined to the original fire building. A good prefire training idea would be to get your crews out on a weekend morning and raise your aerial or access your roofs on your “main street.” Take pictures of the roofs; go back and size them up at the fire station coffee table. Are there skylights that can be accessed? What about ventilation shafts? At these structures it is easy to overlook that the roofs will probably have several thick layers of tar on them. The excess tar will bind the cutting blade of the ventilation saw; plan to have a second rotary saw or extra blades available for quick access in such a situation.

These buildings will require multiple truck company operations. Smaller departments, like mine, that have only a single truck company should not get lulled into thinking that their two- or three-member crew will accomplish the same tasks they can handle at the routine room-and-contents fire. Mutual-aid truck companies will be needed, and you must request them immediately if you want to confine the fire to one building.

The large cockloft spaces may require long hooks from above to knock through ceilings below if the fire is on the top floor. Another good trick is to attach a halligan tool to a rope and toss it over the side of the building to vent the top-floor windows if needed.

Pulling Ceilings

Pulling ceilings and getting through multiple ceilings will be a challenge for your crews. Moreover, if the race against the fire is on by the time an exhausted firefighter gets enough of a ceiling open in the hopes of applying water to stop the fire, the fire might be past him already and on to the next building.

Could an Old Tool Help?

If faced with a fire in the cockloft of Type III buildings and staffing is limited, consider using an older tool that is probably collecting dust in an engine company compartment—the distributor nozzle. When placed in a hole made for this specific purpose—and not ventilation—the distributor may give a commander a shot of at least slowing down the fire’s travel from building to building. These nozzles can deliver more than 250 gallons per minute. Lieutenant Tom Sitz of the Painesville Township (OH) Fire Department has written an excellent article, “The Cellar Nozzle Drill,” on the use of distributor nozzles. You can find it at http://bit.ly/1tAS4Up.

Many of these buildings will have advertising billboards affixed to the roof. Remember that there was a time when your main street was in fact “the main street,” so advertisers used the taller buildings as ad space. Over time, just like fire escapes, these signs will weaken. They also represent an additional roof load that you must consider. Skylights and shafts may assist with venting the cockloft. Billboards will add to the roof load.

Fighting a fire in an ordinary mixed-use occupancy is going to be a battle. Think of it as a battle where some property may have to be sacrificed to save adjacent structures. You will need good command, hoseline selection and placement, and truck operations to win. These buildings will call for big-city tactics on a small-town street. Develop your strategy before the battle occurs.

Additional Links

A SidebySide Comparison of New and Old Construction

Preplanning New Construction

Drill of the Week: Area Familiarization

JOSEPH D. PRONESTI, OFE, is a 26-year member of the Elyria (OH) Fire Department, where he serves as a captain. He is a graduate of the State of Ohio Fire Chiefs’ Executive Officer Program and a certified fire instructor. He is a member of Underwriters Laboratories advisory board, reviewing the effective use of positive-pressure ventilation in structure fires.

Joseph Pronesti will present “What’s Not So Ordinary About a Fire on Your Main Street?” on April 23, 1:30 p.m.-3:15 p.m., at FDIC International in Indianapolis.

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