Fire Feeds on Design Weakness

Fire Feeds on Design Weakness

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Heavy involvement of Building 7 is shown within 35 minutes of first alarm. First-due engine is at left. Deluge set putting out stream at right was put in operation by third and fourth-alarm companies

Miluaukee Sentinel photo.

How fast fire can spread because of a single weakness in building design was dramatically shown by a $750,000, five-alarm blaze this summer in a Milwaukee condominium complex. More than a score of families safely fled the involved area. Many others carted out their possessions from units threatened by the racing flames.

Three factors prevented a conflagration:

  1. Quick, resourceful, well-coordinated attack by fire fighters.
  2. Lack of wind.
  3. Buildings in close proximity only at their interconnected corners, with large open areas interspersed.

All units occupied

The Mill Valley Condominiums were built between 1971 and 1973 on 29 acres in Milwaukee’s far northwestern corner at 119th Street and Appleton Avenue. Unlike a number of apartment complexes involved in large-loss fires in such cities as San Jose and Houston in recent years, Mill Valley was not still under construction. It did not include large areas of wood siding or wood shingle roofs, and its units were occupied.

All 12 of its building modules were basically of the same floor plan: twostory, 18-unit brick rectangles, 125 X 137 feet, containing two “apartments” (units with rooms straddling a dividing wall) at each corner, plus 10 narrower “row houses” along the four sides. All doors opened into a central courtyard (47 X 60 feet) or into passageways near each corner connecting that courtyard with the outside. An underground parking and storage area beneath each module was reached by a sunken driveway into one side of the structure and via stairs from the first-floor level at two of the corner passageways.

Modules were connected together in several groups, one such being Buildings 6 through 9 (see map). As required by local codes and decisions of state authorities—consulted because of questions about whether the modules should be classified throughout as “apartments”—there were three four-hour “fire wall” separations provided within each module, mostly of concrete block extending upward to the roof.

Unfortunately, that’s where the walls ended—beneath the wooden roof deck. There were no parapets. Also, firestopping did not break up the 4 to 6-foot overhang beyond the brick walls of the wooden roof structure (see diagram). In that area, an open space of about 3 1/2 square feet in cross section extended entirely around each module. There were no cutoffs between modules at their interconnection. Furthermore, the soffit forming the lower surface of the overhang was perforated sheet aluminum with thousands of tiny holes admitting plenty of air to fan a fire within.

Map shows initial attack by first and second-alarm companies. Cross and arrows indicate fire origin and spread. Later, an aerial was positioned on lawn at A and an elevating platform at B. Dotted lines show hose pulled through basement garages to reach inner courts. Engine 38 acted as booster, making quick attack closest to fire with tank water supplemented by supply lines from next-due Engine 39 at hydrant.

Shortly before noon on Sunday, August 1, a bright warm day with most tenants at home, the occupant of Apartment 5 in Building 7 near its juncture with Building 8 decided to solvent-clean some bicycle parts in his first-floor rooms. He then left the building—and the solvent container— for a short time. At 11:59, a number of phone calls reported fire in Apartment 5 to the Fire Alarm Office.

Milwaukee Fire Chief William Stamm has been appealing for years to the Common Council for more fire protection in this fringe area. Only two months before the fire, a new station with a new company (Engine 4) was put in service 2 miles from Mill Valley. A new ladder company (21) went in service at another northwest side location during 1972. These two companies were first-due at Mill Valley that Sunday. The initial assignment included four engines, two aerials, a rescue squad, and two chief officers, with an average response distance of nearly 4 miles.

Fire spreading rapidly

“We found a large body of fire in the northwest corner (of Building 7) and spreading rapidly,” reported Chief Leroy Bach of the 7th Battalion. “We had quite a job getting to all the units to make sure the occupants were safely out.”

By that time, fire had mushroomed upstairs, fully involving the apartment of origin. It then pushed into the roof, along both sides of Building 7, and bot h west and north in Building 8.

Direct access to the inner sides of the burning units near the fire’s origin was impossible because of the sunken basement driveway entrances without grade-level access to the courtyards nearby. The rear or west side of the modules themselves faced onto broad grassy slopes down to wooded park land, with no access roads at all.

Several hose lines were dragged into the basement garages, then up inner stairwells to get water into the courtyards. Other lines were laid around the ends of the building group to the west side, and Ladder 3 was driven over the lawns to a point behind Building 7, sinking to the wheel rims in the soft ground. Most operations had to be from the east side only.

Construction problems

There were no continuous balcony or hallway connections between units. While these can spread fire, they also provide places to make a stand—which the common roof spaces did not because of their inaccessibility. Fire in each unit had to be attacked separately, which from the courtyard side could be done only from the ground.

Additional alarms were sounded between 12:06 and 12:24 p.m., to bring a total of 15 engines, five aerials, an elevating platform, and special units. First-alarm companies were positioned to cut off extension of the blaze in four directions.

Reinforcements supplied more water, setting up three master streams to attack the main body of fire. Using 25 2 1/2-inch and 3-inch hose lines, 125 fire fighters brought the blaze under control at 1:27 p.m., but only after 20 dwelling units in Buildings 6, 7 and 8 were destroyed or damaged. Typical prices at Mill Valley ranged from $30,000 to $50,000 per unit.

Hydrants fully utilized

Water supply was fairly good. Almost all hydrants within reach were fully utilized. The main on 119th Street supplying these hydrants was fed by a 16-inch line along the south edge of the property, although near the city’s extreme boundary there are a few crossconnections.

First companies were on the scene quickly, considering the response distance (three got there within seven minutes). Later arrivals were not all so fortunate. The last-in fifth alarm unit—Engine 5-—was preceded by a police escort, but still required more than five minutes to force its way through the last mile to the fire. Sightseers, drawn by black smoke visible for 30 miles, thronged the only two roads into the sparsely settled neighborhood. Chief Stamm himself could not get his car closer than two blocks away. Police from both Milwaukee and suburban Menomonee Falls, aided by sheriff’s deputies, were unable to clear the area entirely.

Start of fire was inside first-floor window just left of tree in right background. Parapet of firewall projects slightly above eave line at upper center of photo. First-in Ladder 21 is battling extension of fire into Building 8. Entrance to Building 7 garage is at center of photo

Milwaukee Sentinel photo.

Cross-section of roof overhang. Both soffit and fascia were supported on wood framing at 2-foot intervals. Similar fascia was attached to ridges, adding considerable fire load at peaks.

Mill Valley was built according to plans that were filed with no local code violations. It is worth noting, however, that the Milwaukee Fire Department had never officially approved the plans having lost that power when the lire prevention bureau was abolished by the Common Council in 1969, two years before the Mill Valley complex was begun.

Destructive overhang

Milwaukee building codes do not permit wooden shake or shingle roofs, which have contributed so much to conflagrations in residential areas elsewhere, but the horizontal flue provided by Mill Valley’s roof overhang proved almost as destructive. Bach and Stamm were highly critical of this as well as of the roof boards bridging the fire walls.

Said Stamm, “The design let melted aluminum and tar splash down on our men as they tried to work under the overhang to open it up and get water in there.”

Bach and one fire fighter were hospitalized with burns, 10 other men received minor injuries.

After launching a review of the building design the day after the fire “to see what went wrong” and saying “our ordinances may have to be strengthened,” Building Department Deputy Inspector Leonard Sloane has since recommended a code change requiring 3-foot parapets on future fire walls in similar developments. A final recommendation to the council by the Advisory Building Code Committee is pending.

Meanwhile, some 50 former Mill Valley tenants are starting over again, thankful that they escaped with their lives.

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