On Wednesday afternoon, fire crews were called back to a condominium complex in Idaho Falls at various times after they first tackled the flames Tuesday night.
To put it into perspective, fire crews responded to reports of smoke and flames at these condominiums nearly five times in the last 12 hours.
"On a large fire like this, it's not uncommon to come back for a hotspot," said Landon Johnson, Idaho Falls fire captain.
Fire crews said the initial fire was relatively easy to put out, but the problem they're having lies within the building construction itself.
"The nature of the design of the building and the concrete exterior that they use, makes for a pretty tough extinguishment because the fire gets a chance to hide," said Johnson.
Crews say in this case, fire hid behind the multiple layers of the 40-year old attic--fiber board, chicken wire, and concrete and that has trapped the heat inside. Firefighters sprayed foam throughout the attic, in the hopes of preventing future flames.
"That foam will cling to the charred wood and release water into the wood through the foam," said Johnson. "Hopefully that'll stem the tide of the rekindles."
The homeowners association and building developers say the reason the structure didn't burn clear to the ground was because it was built with proper fire prevention measures.
The two units next to the ones that were badly damaged only sustained minor smoke damage.
Fire investigators say the estimated damage for the building is around $250,000. The cause of the blaze is under investigation.