BOULDER, Colo. — After a nearly four-month investigation, Boulder Fire-Rescue (BFR) released the cause of the Whittier Apartment fire that happened Oct. 19 affecting 81 units across six buildings.
BFR said the cause of the fire has been declared to be "undetermined."
In a news release BFR said, "From the origin area, the fire spread rapidly on the exterior of the structure. The exterior was typical wood frame with wood exterior siding and other combustible construction components. While there were no fire sprinklers on the exteriors or within the attics of the buildings, the occupied space of all six buildings, as well as the garage, were fully fire sprinklered. From the investigation it was determined that the fire sprinkler system for the interior apartment buildings and garage did operate and function correctly. In addition, there was no known fire or building code violations that would have led to the fire."
BFR with assistance from the Boulder Police Department and the Denver Field Division of the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), worked to determine what caused the fire. They used K-9 accelerant detection dogs, comparative analysis of possible ignition sources and extensive lab testing to find a cause. After reviewing all reports and findings the BFR said that no ignitable liquids were found nor any other found sources of ignition.
From these findings, BFR determined that the cause of the fire was declared undetermined with no evidence of intentional fire setting.
>> WATCH: Dennis Arnold records as his apartment complex burns
One couple who lost everything in the fire, Katie Burckel and Dennis Arnold said the how and the why doesn't change how they move forward.
“The one good part about this total loss of ours is we get to, everything we’re replacing are things that we need now, there’s no excess there’s no extra," said Arnold.
Burckel didn't have renters insurance but Arnold did. Unfortunately, though, his policy didn't include many of the more expensive things he had accumulated over the years.
“We’re like 35-40% through the list and we’ve already exceeded what I had coverage for," he said. So we lost a lot of things that will just have to come out of pocket to replace."
The pair moved to Louisville and found themselves threatened by fire once again just a couple of months later.
"It's emotionally rough, dealing with the thought, the possibility of going through the same thing again," said Arnold.
But after they evacuated, they still had an apartment to go back to, and advice for Marshall Fire survivors going through losing everything.
“I think just enjoy things while you have them, and then find a way to make peace with it," said Burckel.
A friend started a GoFundMe for Burckel and Arnold, and even several months later, they are still working to replace things.
The apartment at 2301 Pearl St. left people in 81 units displaced. Two people sought treatment for minor injuries, BFR said no one else was injured.
The fire department said the apartment complex is a mix of owner-occupied units, long and short-term rentals, and vacant units. Ten CU Boulder students were impacted by the fire.
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