The Building Is Your Enemy - Part 5

Francis L. Brannigan, SPFE, discusses why it’s important to know the inside and outside of building construction in his conclusion of a two-part summary of wood construction.


This article concludes the two-part summary of the 54-page Chapter 3, "Wood Construction," of the 667-page third edition of my book, Building Construction For The Fire Service . Part 1 of "The Building Is Your Enemy" was published in Firehouse® February 1996, part 2 in August 1996, part 3 in...


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Siding is the exterior weather covering of the building. It may be solid wood, plywood, shingles, asphalt- based imitation stone or brick, aluminum, vinyl, stucco, brick or stone, asbestos-concrete shingles. Whatever the siding, the building is a wooden building.

Except for metal and masonry, all siding is easily ignited by an exterior fire or by auto-extension of fire from floor to floor.

All wooden buildings are liable to ignition from exposure fires because of the windows.

Fire departments with significant exposure potentials must have standard operating procedures (SOPs) that bypass the usual initial attack with small lines to mount a heavy-caliber defensive attack. These plans may even include sacrificing the original heavily involved building to devote all resources to cutting off a possible conflagration.

7_98_building2.jpg
Illustration by Christopher Brannigan
Heavy timber structures have a "good press," but beware. Fire-vulnerable connections like this steel connector are one of the principal weaknesses. (See Building Construction For The Fire Service, third edition, page 129.) Know your buildings!

In one case of a fast-spreading fire in wooden apartment houses, it was reported that shorthanded units had difficulty getting heavy-stream appliances into place on the ground because of their location high up on the apparatus. Units, especially those undermanned, should drill on getting heavy-stream appliances into operation as rapidly as possible. Time standards should be set and slower units should drill regularly on this evolution.

Firefighters operating handlines should not get into narrow spaces between the fire building and the exposure, firefighters have died when the fire building collapsed. Plan to use heavy-caliber stream appliances for such exposures.

Brick veneer siding is very common and can be dangerous. The word brick seems to connote strength and durability, e.g. "built like a brick outhouse." Brick masonry, usually a composite with concrete block, structurally supports the building. Brick veneer is not structural. It is just another siding, but a potentially dangerous one. A one-brick-thick wall is very unstable. The brick is tied to the basic structural wall, usually wood but occasionally concrete block, cast concrete or even steel, with steel ties. When finished, it looks like any structural wall.

In older buildings about every seventh course (layer of brick) was turned so the only the headers (the ends of the brick) showed. This tied the wall together. Brick veneer was laid all stretchers (the long side of the brick showing), thus you could tell one from the other.

Many times, the header bricks would crack. Wire trusses were developed. They are laid in some of the mortar joints between courses and eliminate the headers. You can no longer tell brick veneer from brick masonry.

Some buildings have bearing walls of solid masonry and non-bearing walls of cheaper brick veneer. Others may have a first story of load-bearing masonry and upper floors of brick veneer.

Don't get people injured or killed in the collapse of a brick (or stone) veneer wall. If the basic wall is steel, movement of the steel, may throw down the brick. If the wall is wood, the burning of the wooden wall deprives the brick veneer of support and it may likely collapse. This is not a structural collapse, but the veneer bricks are as heavy and hard as structural brick. Your new standard helmet may not help you. If you get hit with a mass of bricks, your helmet frontpiece may become your belt buckle!

An old wooden house in New York City had been "rehabilitated" by the addition of a masonry veneer wall. It was heavily damaged by fire. During overhaul, an interior collapse knocked down the brick wall. A lieutenant was killed while pushing an injured probationary firefighter out of harm's way.

Wood-Shingle Roofing

Wood shingles or shakes are split pieces of wood used for roofing or siding. Shakes are larger than shingles. Some of the greatest fire disasters in history have been due to the spread of fire by wood-shingle roofs.