1920-1940

House wiring over the years

Knob-and-tube wiring, minimal outlets, and basic lighting, marking an era of electrical simplicity.

In the 1920s, residential electrical systems were primarily characterized by knob-and-tube wiring, a method that utilized ceramic knobs to secure wires along the house’s framing and ceramic tubes to safeguard wires that passed through joists or studs. Unlike the concealed wiring methods of today, wiring during this period was often exposed and visibly installed. Despite its widespread use, knob-and-tube wiring presented several limitations and safety concerns, which eventually led to significant advancements in electrical wiring techniques in the subsequent decades.

Typically, homes were equipped with a mere 60-amp service, and the electrical panels primarily featured screw-in fuse panels without any specific protection for individuals. Kitchen areas were minimally outfitted, usually with just one or two receptacles and a single central light operated by a switch. Bedrooms in many cases lacked electrical outlets altogether. Hallways might have been illuminated by a single sconce light with an accompanying switch. Living rooms were similarly sparse, with perhaps one or two receptacles and frequently no overhead lighting.

In the bathroom, one might find one or two wall-mounted sconce lights controlled by switches, but receptacles were notably absent. The exterior of the house was typically limited to a single coach light adjacent to a door, controlled by a switch, with very few, if any, outdoor receptacles. This stark simplicity and the limitations of early 20th-century electrical infrastructure highlight the dramatic evolution of residential wiring practices to accommodate the growing demand for electricity and enhance safety standards.

Bring your homes electrical up to code and into the 21st century

  • Update the service to a minimum of 200 amps.
  • Install a new panel with people protection features.
  • Incorporate arc fault and GFI (Ground Fault Interrupter) protections.
  • Conduct whole home rewires.
  • Remove or deactivate all knob-and-tube wiring.
  • Install overhead lighting in living rooms.
  • Add ceiling fans in bedrooms.
  • Implement recessed lights and undercabinet lighting in kitchens.
  • Enhance exterior lighting.
  • Increase the number of receptacles in all rooms and exterior areas.
  • Wire for interconnected smoke detectors.

Don't hesitate to contact us for more information.

~ Chris Coffin, 4th Generation Master Electrician &
Owner of Coffin Electric

Frequently Asked Questions

Knob-and-tube (K&T) wiring was a common electrical wiring method used in homes during the 1920s. It involved the use of ceramic knobs to hold wires in place along the structure of a house and ceramic tubes that served as protective casings for wires passing through wood joists or wall studs.

K&T wiring was typically installed in an exposed manner, with wires visible along the framing of the house, unlike today's concealed wiring methods.

Despite its widespread use, knob-and-tube wiring had several limitations, including safety concerns and a lack of capacity for modern electrical loads. This led to the development of more advanced wiring methods in later decades.

Homes with knob-and-tube wiring often had an electrical service capacity of only 60 amps, which is significantly lower than modern standards.

Kitchens in the 1920s usually had minimal electrical outlets, often only one or two receptacles, and a single light fixture controlled by one switch.

It was common for bedrooms to have no electrical outlets at all during the era of knob-and-tube wiring.

Hallways might have featured a single sconce light with a switch, while living rooms could have one or two receptacles and often lacked overhead lighting.

Bathrooms typically had one or two sconce lights with switches but no electrical receptacles.

The exterior of houses from this period rarely had electrical receptacles. It was common to have a single coach light by a door, controlled by a switch, with very few outdoor receptacles available.

Knob-and-tube wiring fell out of favor due to its limitations in capacity, safety concerns, and inability to meet the growing demand for electrical appliances and modern household electrical loads.