What’s the difference between a heavy duty (12 gauge) extension cord and the 12ga wiring inside the walls of a typical north American home? Why can’t you just chop the ends off and use it to wire up an outlet?

Question

What’s the difference between a heavy duty (12 gauge) extension cord and the 12ga wiring inside the walls of a typical north American home? Why can’t you just chop the ends off and use it to wire up an outlet?

In: 250

Answer 1

Electrician here. It’s a code violation. An extension cord isn’t designed or listed for permanent use or for being concealed inside walls. Also cutting the ends off would violate the listing for its normal use as an extension cord.

In the US the standard for installation of electrical conductors and equipment is the National Electrical Code. Flexible cords and cables are covered by Article 400 and 400.12 specifically says they shall not be used as a substitute for the fixed wiring of a structure or ran through walls or holes.