DeKalb Fire Department officials confirmed Monday that an electrical failure caused Friday’s fire which gutted a house at 355 Augusta Ave.

But officials said the actual wiring problem “will probably never be known” because of the extent of the damage.

“We can’t nail it down to a specific wire,” Assistant Chief Reuben Nelson said. There was about $300,000 damage, he said.

Firefighting units arrived at the scene less than two minutes after they were called, Nelson said. Water hoses were advanced to the second floor within another five minutes, he said.

However, firefighters did not begin immediately fighting the blaze because the “first priority of any initial fire attack” is checking the house for tenants, Nelson said. “It’s always the primary concern.”

The fire department had to tear out the house’s walls and ceilings to combat the fire, which was burning and spreading inside “void areas,” Nelson said.

By the time firefighters tore down the walls, the fire had spread through the top floor and prevented an inside attack, Nelson said.

Firefighting efforts “were the best that could have been done under the circumstances,” Nelson said. “The last thing you want to do is have a firefighter killed.”

One firefighter was overcome by heat and smoke during the blaze.

The building, a licensed rooming house, passed inspection in late October after two or three checks, said Bill Nicklas, DeKalb Building and Community Services director.

The building is “probably not worth rebuilding” because more than half of it was destroyed, Nelson said.