Natural ventilation, a wood balloon-frame home and a load of highly flammable material on the porch created ideal conditions for the rapid escalation of a fire that destroyed one home and severely damaged two others on the 800 block of Clinton Avenue May 4, according to Oak Park Fire Chief Tom Ebsen.
Ebsen told the board and residents at a Village Hall meeting on Monday that suppression of the fire, which broke out on the south half of the front porch at 814 Clinton Ave. at around 4 a.m., also was delayed due to the failure of a fire engine water hose valve on one of the engines. He said that the faulty valve is regularly tested and has since been replaced.
Ebsen said the fire was so intense that firefighters were, "unable to do any interior operations at all."
"In my 34 years of being in the department, [these are] the worst residential fire conditions that I have ever seen, and talking to chiefs who were at the scene, they had expressed similar thoughts to me," Ebsen said.
Despite the delay in use of the water valve, Ebsen dispelled rumors that fire hydrants in the area were unable to supply enough water pressure to adequately fight the fire.
In a report released Monday, Ebsen noted that the malfunctioning water intake valve on the fire engine required firefighters to "relocate the supply hoses to an alternative intake port on the side of the engine," but added that once accomplished, "the engine had an adequate supply to deliver approximately 500 gallons per minute via multiple hose lines."
Resident John Powers, who lives near the site of the fire, said that the night of the fire he was told by one of the firefighters that the hydrant was only able to provide 28 gallons per minute.
Ebsen said that if that is what he was told, then he was misinformed.
"I don't know where the 28-gallons-per minute comment came from unless (the incident commander) just misspoke," he said.
Ebsen said an upholstered sofa and two stacked planters of dead vegetative material on the porch caused the fire to spread more quickly. He also noted in the report that the style of the home built in 1908 – with a wood porch, wood exterior siding and a structural wood frame built in the balloon-frame style typical for the era – also led to the rapid spread of the fire.
A wind from the west-northwest, combined with open windows in the front of the home and open doors in the rear, created natural ventilation, Ebsen said.
Since the fire broke out early in the morning, there was no one awake to detect it, allowing it to spread further, the report noted. Had the fire taken place during the day, it might have been reported at an earlier stage, he said.
The fire department still has not determined the cause of the fire because evidence was destroyed in the blaze, Ebsen said. The department's three hypotheses include an electrical outlet on the exterior wall of the front porch, discarded smoking material or vandalism.
Ebsen said the electrical outlet was located behind the sofa, and although residents say nothing was plugged in, old wiring can create high resistance and cause nearby material to catch fire.
The report notes that vandalism and smoking material are being considered as potential causes "because it was an open, unsecured front porch."