I recently purchased a home built in the 1920s. While touring the property initially, I could see that the electrical system was very outdated. The wiring was a tangled mess hidden behind walls and the fuse box looked ancient. I knew I would need to rewire the home for safety and efficiency, but had no idea where to start. After doing some research into historical wiring methods, I uncovered secrets that made rewiring my vintage home much easier.

Knob and Tube Wiring

One of the earliest forms of electrical wiring found in homes is knob and tube wiring. This method was commonly used from 1880 to the 1940s. It features:

The pros of knob and tube wiring is that it can last a very long time when undisturbed. However, the lack of a ground wire and old insulation materials make it a fire hazard. I had to carefully remove all knob and tube wiring when rewiring my home.

Armored Cable (BX)

Armored cable, or BX wiring, came into use in the early 1900s. It features:

BX wiring is very durable and safe. When rewiring, I was able to simply bypass old BX runs by making new connections in accessible boxes. This saved a lot of time and avoided the need to rip open walls.

Running New Wiring

While I kept some BX wiring, I did need to run all new wiring in certain areas. Here are some tips I learned:

I also updated the electrical service panel to a 200 amp breaker system. This involved running new service wires from the utility connection to the house.

Key Safety Steps

Rewiring an old home comes with risks if safety steps aren't taken:

By understanding the unique wiring methods used in old homes, I was able to rewire my 100 year old home much faster and safer than expected. While challenging at first, uncovering the past secrets of knob and tube and armored cable wiring gave me the knowledge I needed to update my home's electrical system efficiently.