Firefighters warn homeowners of a hidden danger

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ST. LOUIS COUNTY, MO (KTVI) - Fire wiped out a Ballwin home and sparked a warning from firefighters about a very prevalent, but hidden danger in St. Louis area houses: aluminum wiring.

A West County EMS & Fire “Helmet Cam” showed the extensive damage to a home in the 900 Block of Glen Mill Drive late Saturday afternoon.

Homeowners often overlook aluminum wiring.  It's popular in homes across the area, built from the mid-60's to mid-70's.

You need to know if it's in your house, firefighters said Monday.

The residents on Glen Mill Drive thought they had already had the fire put out when they called the fire department.

“They found this outlet downstairs in the first floor, that was actually on fire, had flames coming out of the outlet,” said Dan Bruno, Fire Marshal for West County EMS & Fire.

The residents doused the outlet with an extinguisher and saw no more flames, he said.

A few minutes later it was obvious the problem went beyond a bad electrical outlet.

The fire actually started in a bank of light switches on the sun porch attached to the back of the house where newer copper wiring was tied into the home’s original aluminum wiring, Bruno said.

“What happens is, that aluminum and copper wiring expand and contrast at different rates; it starts to separate, arcs across, a lot of carbon buildup.  It’s just going to start a fire,” he said.  “It burned completely through the 2x4’s in the wall and it started running laterally in the wall.  It came out a different outlet.  That’s when the occupants saw fire coming out the outlet.”

By that point fire had spread from the exterior porch throughout the walls of the house, he said.

Firefighters urge homeowners to see if they have aluminum wiring.

“It doesn’t make the house unsafe.  It just means that the wiring in the house needs to be checked out by an electrician and maybe have some things done,” Bruno said.

One common mistake:  using standard light switches and outlets with aluminum wiring.

The standard switches and outlets that are so popular today are not rated for aluminum wiring.

There are also special connectors made for joining copper and aluminum wiring.  An electrician can check for you.

Here’s a link for more information about aluminum wiring in your home.