Bungalow Fires: Construction Dictates Tactics

BY BRUCE TENNISWOOD

The bungalow was the home design of choice for middle class America during the suburban housing boom, post-World War II. They’re everywhere. They provided a low-cost alternative to multifamily residences found in the inner city, provided plenty of room for the large families of the 1940s and 1950s, and were symbols of American prosperity during the Baby Boom.

Today, they have a new legacy: They are often the structures burning when we get called to residential fires. The reasons for their burning at such a high frequency are numerous, but two stand out as primary. These homes are commonplace in rundown neighborhoods where pride of ownership has been replaced with renters who have little regard for property values, maintenance, housekeeping, or fire safety. Additionally, since so many of these houses are in existence, we see them in fire situations often based solely on their number.

This article addresses fires in bungalow-type, single-family residences, the unique characteristics of this construction style, and problems I have so often observed.

 

BASIC CONSTRUCTION

 

The basic construction of a bungalow, or “story and a half,” is a rectangular house, often on a basement that is approximately five to six feet in the ground, with a partial second-floor covering the middle section of the structure. A bungalow has a few common characteristics that stand out as obvious signs of the construction type. During construction, most builders included a window on each end of the house, centered under the peak. The roof pitch is typically 12:12 or steeper. There will normally be a gable vent above the window on each end of the house. Frequently, roof vents can be found approximately one-third of the way up the roof on both the front and rear of the home. Bungalows typically do not have significant overhangs, although some have been added later as the homes were remodeled.

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(1) Typical bungalow identifiers include a centered second-floor window, a gable vent, an exposed foundation, and a side door. (Photos by Richard L. Story.)

Inside the home, the layout typically consists of an interior stairway, with the basement stairway in front of a side entrance. The first floor consists of a kitchen/dining area, a living room, a bathroom, and two bedrooms. The stairway to the second floor leads up from the living room to an area approximately 12 feet wide by the length of the house. Knee walls, approximately three to four feet high, are down both sides of the space. A sloped section of ceiling and a small section of flat ceiling are in the center of the space. These homes are often finished inside with wet plaster, creating a significant fire barrier between the living space and the structural voids. The second floor was normally constructed to be a “bonus room” for future finishing by the homeowner and, therefore, may be present in any number of layouts and finish materials. I have seen them completely unfinished, finished in drywall or wet plaster, knotty pine 1 × 6, and even plywood. Each finish creates challenges to firefighting operations.

The original kitchen cabinetry used a common construction technique from the period these homes were built. Modular cabinets were not the standard as they are today. Cabinets were built as a part of the structure, anchored securely to structural members such as wall studs and soffits. Left in their original condition, these cabinets provided a degree of safety from fire spread. However, most of these old cabinets have long since been replaced with modern modular cabinets. The old cabinets were often torn out and their structural members pried loose from the house structure, leaving openings that were conveniently covered by the new cabinets. Observers would never see the holes in the plaster walls and soffit, but a kitchen fire tells the tale almost immediately.

 

TACTICS

 

Kitchen fires in bungalows will normally turn into a second-floor attic fire unless you understand these characteristics and aggressively pursue the fire through these paths of travel. You need to enter the void space behind the knee walls in bungalow-style houses as soon as possible to find and stop fire spread. This is one time that making an assumption is the correct course of action. Assume that if there is fire behind a cabinet, there is fire behind the knee wall.

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(2) Fire in one concealed space can quickly develop into total upper-level involvement.

A common error with house fires in this type of structure is failing to understand how the construction affects fire travel. These homes normally have 2 × 8 ceiling joists over the first floor that span from one outer wall to the other. The joists are supported in the middle over a “bearing wall,” which provides a sturdy platform for the floor of the second floor. However, the joists provide a space for fire to travel from one side of the house to the other. Additionally, the builders of these homes normally fastened a 1 × 6 subfloor in a diagonal fashion to create the floor of the second floor. This floor covers the area between the knee walls only, leaving the area behind the knee walls open to the roof and floor structures. Any fire that enters the void created by the joists has free run across very dry wood to both sides of the structure. Fire can easily enter through any breaches, such as plugs, switches, light fixtures, return air vents, kitchen or bath vents, and cabinet remodel breaches.

Once inside these voids, the fire is fanned by the draft inherent in the construction of a bungalow. The fire is drawn to the void behind the knee walls and travels up the roof rafters behind the angled ceiling of the second floor to the top of the roof structure, where it can vent through a ridge or gable vent. This natural ventilation/draft characteristic results in rapid movement of fire from a simple room-and-contents to a fully involved structure fire within a remarkably short time.

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(3) The bungalow’s features can be modified but still have telltale indicators of the construction type.

You must make proper tactical decisions promptly on identifying a fire in a bungalow. Assume any fire in a bungalow has resulted in flame spread to the attic areas. Positive pressure is helpful in firefighting operations, but it will result in faster fire spread in the voids. Do not institute positive pressure on a bungalow until adequate personnel are ready to gain access to both knee wall spaces. Watch for signs of backdraft from all three void spaces, and use preventive ventilation techniques if indicated. For any plaster or drywall breaches with direct flame impingement, overhaul must include opening the area around the breach far enough to confirm the outer boundary of fire involvement. Remove from the wall modular cabinets with flame impingement to the rear or sides to check for entry points into the structure. Remember that cabinet removal does not have to mean cabinet destruction. Four long screws are likely all that are holding the cabinets to the wall; you can easily remove them with a power screwdriver.

Bungalow fires are dangerous and fast-moving. Fortunately, they are relatively predictable if you learn to read the signs:

  • If the fire is in the kitchen, it’s probably in the attic.
  • If the fire is in one knee wall attic area, it’s either in the other area or it’s heading there.
  • If the fire is behind the knee wall area, it’s probably in the area above the second-floor ceiling.

 

Make sure that personnel coordinate their ventilation and attack operations to provide a safer firefighting environment.

 

•••

 

Recently I responded as mutual aid on a kitchen fire—a bungalow with light smoke showing from the attic and a significant stove fire. After numerous attempts to convince the soon-to-retire incident commander to overhaul the kitchen and attic more aggressively, including bluntly stating that the fire was not out, I was told my company was no longer needed. Heading back to our vehicles, I told my driver to clear the scene but not to get comfortable because we would be back shortly. Experience can sometimes tell more than a thermal imaging camera or a yard full of impatient firefighters. Sure enough, less than an hour later, we had a full-blown structure fire on our hands.

BRUCE TENNISWOOD is deputy chief for the Westland (MI) Fire Department. He has a B.S. in fire science from Madonna University, where he is an MBA student, and is enrolled in Staff and Command at Eastern Michigan University. He is a fire office III and an AEMT.

 

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