Over the years, builders and public authorities have recognized that fire can spread easily from one combustible building to another and have tried to control the cause of a potential conflagration.

1) This wall has a brick nogging (bricks placed between studs in a wood stud wall) “fire barrier.” Note the open floor voids and the common cockloft. The bricks do not make an impervious fire barrier. (Photo courtesy of author.)

My grandparents bought a new three-story row-frame house in the Bronx in 1889. I was told that a brick wall would keep us safe from a fire next door. This was not true. Such row houses in New York City and elsewhere had brick nogging inserted in the wall in a naive attempt to stop a fire from extending (photo 1).

A wood stud party wall is common to both buildings.

The floor voids are open to one another, and there is a common cockloft. In a recent row-building fire in New York City, a radio report said, “We have fire in the wall of exposure 2.” There are many gaps in the brick nogging. We may call the individual units “exposures,” but to the fire, row buildings are in effect one building and should be regarded accordingly.

Similar deficiencies have been noted in modern “townhouses,” where the firewall is used as a bearing wall and girders (a beam that supports other beams, wood, or steel) from both buildings are in a common socket.

A Scenario

The incident commander (IC) gives full attention to the fire in this basement. Suddenly, it is apparent that fire has a good hold on the first-floor truss floors of either or both exposures, making interior attack too dangerous.

In construction-field problems, the devil is in the details. This one detail can result in the destruction of three homes, if not more.

Know your buildings. Study and record buildings under construction. Document problems, and have them arranged so the dispatcher can pass information to the IC. Do not depend on memory; the fire may not occur for many years.

At a fire in such a building, plan to deploy units immediately into the first floor of the exposures. Check immediately with your thermal imaging camera (TIC, the firefighter’s radar) for fire in the floor. If there is fire, get out; collapse is unpredictable.

If there is no fire, get into the basement and check the overhead area for fire with the TIC. Pull the ceiling near the girder; have a charged line on hand because the added oxygen will accelerate a tiny flicker in the void into a full-blown fire. You may cut the extension off before it gains control of the exposure.

The proper firewall has no penetrations and, in the case of flammable exterior construction, is extended out or is T- or L- shaped to prevent exterior extension.


We are indebted to Battalion Chief W. Neal Fisher of the West Hartford (CT) Fire Department for the following information about a unique fire barrier.

(2) This neighboring structure shows what the fire building looked like before the fire. (Photos by Chief W. Neal Fisher.)

“In early January of this year, we had a serious fire in a residential, wood-frame duplex (photo 2). One resident was trapped on the second floor and died. We were taking some extra risk because of the life hazard. The crew made it to the base of the stairs. At about the same time, the concrete blocks (photo 3) started falling out of the dividing wall (between units) and landed at the top of the stairs. Had the crew made it up the stairs, they could have been struck by these concrete blocks.

(3) Concrete blocks extended to the underside of the roof, but there could have been a gap. In any case, the fire was in the porch of both units on arrival.

“The blocks were held between two-inch by six-inch studs and were mortared together. The blocks were approximately 15 inches wide, two feet high, and as thick as the studs; they weighed about 90 pounds each. I don’t know if the original purpose of the blocks was soundproofing or fire protection. The blocks went from the basement to the underside of the roof and probably fell in because the roof was failing and created a lateral load on them.

“I feel fortunate that the engine crew did not make the second floor; it is very likely that they would have been hit by the blocks.”

My Comments

It would appear that the blocks were made locally to fit the stud spaces better and more quickly than brick. Chief Fisher will try to determine if these are unique or, as I suspect, widely used in the area. If any reader has ever seen this construction elsewhere, please drop me a note at Fbrannigan@comcast.net.


In The Ol’ Professor of February 2004, I discussed the potential hazards of this new material. Become informed about this material before a tragedy occurs. Keep in touch with local suppliers; learn where it is installed. Like an egg, you can’t tell good from bad simply by looking. Assistant Chief E. Murphy of the Roberts Park (IL) Fire Protection District has conducted some realistic tests involving this material and will e-mail a copy of the report on request. He can be reached at emurphy@robertsparkfpd.org/. I have not yet been able to get a prominent fire service member to take an interest in this new hazard. Send for Chief Murphy’s report and distribute it to your state training authorities. Use it in any other way to get out the word. Perhaps we will be able to avert a tragedy.


October 13, my 86th birthday, marks the 62nd anniversary of my abandoning forensic accounting and converting from an enthusiastic buff and student of fire protection to a full-time professional. I was commissioned in Panama as an Ensign USNR from my former status as a 2nd class petty officer.

The first week I was commissioned, I recommended a major change in the layout of hydrants for a tank farm, which saved the Navy a substantial sum. But, it made no impression. The next week, I inspected a naval facility. I did not make recommendations. I told the commander that I would get equipment out to his facility and would come to train his personnel. This so impressed the crusty senior commander, who was the admiral’s buddy, that he was prompted to say, “If we get a few more like the guy you sent out here, we can win this @##$ war.” As a result, I had the complete backing of the 15th Naval District commandant for my various ideas, which led to my commanding a Navy Shipboard Firefighting School and the start of my career.

Lesson: Do what you can to impress persons who have the ear of the “Big Kahuna.”

FRANCIS L. BRANNIGAN, SFPE (Fellow), the recipient of Fire Engineering’s first Lifetime Achievement Award, has devoted more than half of his 62-year career to the safety of firefighters in building fires. He is well known as the author of Building Construction for the Fire Service, Third Edition (National Fire Protection Association, 1992), and for his lectures and videotapes. Brannigan is an editorial advisory board member of Fire Engineering.

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