How Much You Can Keep?

Basically, you can retain any and all safe wiring and devices. An electrical system will do what it’s designed to do and will do so reliably until you extend a circuit or the system beyond its design. You should remove or replace the following:

• Any corroded or damaged wiring
• Wiring that has not been installed properly (such as wire running along the bottom edge of an exposed joist rather than through holes drilled in the joist)
• Devices or fixtures that render a circuit unsafe
• Conductors that are the wrong gauge for their circuits
• Any cable rated for interior use but installed outdoors You might be getting more than you bargained for if your system has been repeatedly altered over the years.

If additions have been made based on convenience (“Hey, look! I found a couple of wires.”) rather than logic, you could end up with an odd variety of lights, receptacles, and other fixtures all over your house. It might be best to run a new circuit or two to cover all these miscellaneous runs if you’re not already rewiring the whole house.