Old wires are danger that's out of sight and out of mind, until they fail.

That happened twice on Sunday, causing two separate house fires. The fire on E. 9th Street just raised a scare with some smoke. But fire on W. 3rd blazed for hours, and left the home a total loss.

New Erie homeowner Axy Ruiz had no idea what dangers were in his walls until his pipes froze, burst, and left a hole in his kitchen wall.

"You don't know until the problem happens. We wouldn't have known the wiring was that old due to the fact that it was hidden behind walls," Ruiz said.

The inspection by J.E. Hilbrich Electric found wires held together by electrical tape, old-form insulated with fabric, already starting to fray, and extension cords built into the walls - a high risk for power overloads.

"This is called an illegal splice, meaning the power source is split," said John Hanke, an electrician for J.E. Hilbrich and former Fire Chief of the Keasarge Fire Department. The cord ran from the basement wall upstairs, likely to a kitchen outlet.

"Especially running a refrigerator or a microwave, that extension cord is going to break down and it's going to cause a fire," Hanke said.

Old wiring is not an isolated problem.

"Probably 35% of the homes in Erie still have this old wiring system in them," said John Hilbrich of Hilbrich Electric, holding an outdated wire. The wire was insulated with paper and fabric, and not designed to handle the electrical loads commonly used by households today. It becomes a safety hazard when the cords are overloaded, then start to fray and spark. 

Adding to the problem: old houses have fewer outlets, which further raises the risk of overloading a circuit.

"A lot of the houses we go in to when we do a residential re-wire are operating off of four to six circuits for the entire house. Under today's standard code, we're putting four to six circuits in the kitchen alone," Hilbrich said.

Rewiring a home isn't cheap, typically costing between $5,000-$9,000 depending on the size of the house.

Ruiz wasn't expecting the extra cost of rewiring when he bought the house, but he does see the sliver lining.

"Knowing a little bit about electrical stuff, that old wiring if it gets wet, could've sparked a real bad fire," he said. "And rewiring the house, now I can remodel and get a whole new kitchen."

Houses built before 1980 are installed with old wiring. Residents unsure of whether their home has been updated can contact a licensed electrician for an inspection.