Update: The Iowa City Police Department announced on Wednesday afternoon that the 100 block of E Burlington Street will remain closed into Saturday, as crews continue to remove debris from the site of the fire.
On Wednesday afternoon, Iowa City Fire Marshall Brian Greer release a statement on the results of the investigation into the cause Tuesday’s fire at the Hieronymus Square building project.
The investigation, which included interviews and a physical investigation, found that the fire started in a third-floor room on the north side of the building.
The room had a temporary 10′ by 10′ tent structure used as a warming area for combustible subfloor adhesives. The tent housed several cases of the adhesives and a liquid propane-fueled radiant heater. The heater was fueled by a liquid propane tank outside the tent.
The heater came in contact with the combustibles in the tent and started a fire. Flames grew and the liquid propane tank started to vent, providing more fuel until it exploded. Strong winds then carried flames through the structure rapidly.
It took almost three and a half hours for fire crews from Iowa City, Coralville and North Liberty to completely extinguish the fire, which started at approximately 2:45 p.m. on Tuesday. The first unit from the Iowa City Fire Department arrived on the scene within three minutes of the fire being reported.
According to Greer, it is “estimated that the initial loss [caused by the fire] is $1,000,000.”