In the late 1800s, Thomas Edison ushered in a new era of electric lighting and power in American homes. His DC power transmission system enabled electricity to be distributed efficiently over long distances for the first time. However, Edison's initial wiring system was crude, dangerous, and sparks flew when it was adopted for indoor use. This sparked major controversy, but also paved the way for safer, more advanced wiring methods that transformed home design and living standards.

Edison Lights Up New York City

In September 1882, Thomas Edison flipped a switch and illuminated 85 streetlights in lower Manhattan from his Pearl Street Station power plant. For the first time, a neighborhood was lit by electricity. This marked the beginning of Edison's plan to build power stations and run electric lines into homes, dramatically changing how people lived.

Early Wiring Methods - Crude and Dangerous

Edison’s initial wiring system used copper rods installed in home walls with little insulation. This exposed wires throughout living spaces. Any break in insulation could release deadly current. Fires frequently started from sparks and overloaded circuits. The system was extremely dangerous by modern standards.

Homeowners also disliked the aesthetics of exposed wires snaking across walls and ceilings. Many referred to it as “knob and tube” wiring. But with no better alternative, dangerous exposed wiring prevailed in the 1880s and 1890s.

Public Outcry Against Dangers

After several deadly accidents, public outcry rose against the hazards of Edison’s wiring method. Newspapers published horror stories of fires and electrocutions linked to faulty wiring. Many cities began requiring insulation for all indoor wiring.

"Edison’s bare copper wires are like deadly serpents running through every home! We desperately need insulation for safety's sake," one New York Times article proclaimed in 1889.

Edison downplayed the dangers at first. But the public backlash sparked a major shift toward safer, insulated wiring.

Development of Insulated Wiring

In response to public safety concerns, work began on inventing insulated electrical wiring suitable and affordable for homes. Insulation would prevent contacts between wires and surfaces that could release current.

Thomas Edison himself played a role in these developments. In 1880, he patented a short-lived method using compressed cardboard tubes as makeshift insulation.

Harvey Hubbell's invention of a threaded wooden insulation bushing in 1890 was another milestone. It enabled wires to pass securely through holes drilled in walls and beams. This was the forerunner of modern electrical fittings and connectors.

However, rubber insulation proved most pivotal. Flexible, durable, and inexpensive, it revolutionized interior wiring, preventing dangerous sparks and currents from escaping wires.

Safety Standards Emerge

Insulated wiring came into widespread use in the 1890s and 1900s. As electricity grew more common in homes, local governments enacted electrical codes mandating certain safety standards.

Requirements included:

These simple standards made electrical fires and accidents far less common. They ushered in a new era of safer, functional home wiring.


Once insulated wiring was required, electricity could be used anywhere inside homes without fear of stray electrical current escaping.

Creative new lighting options emerged, like wall sconces, chandeliers, and desk lamps. Electrical appliances and fixtures could now be permanently installed and wired safely in kitchens, workshops, and bathrooms.

This interior wiring revolution even enabled new home design layouts. With lighting and equipment no longer dependent on gas lines or water pipes, kitchens, bedrooms, and work rooms could be designed and located flexibly.

Edison’s wiring system truly transformed home life at the turn of the century. The added comfort and functionality seemed wondrous, if not magical, to many. As one 1909 journalist described:

“The drudgery of household tasks fades in homes graced with electrical light and appliances. Simply flip a switch, and your home is bright and alive with modern convenience. Truly we are living in a golden age.”


While the hazards of Edison's primitive wiring appalled early adopters, this sparked major safety advances. Insulated wiring and regulations ultimately created new standards for safe electrical integration. Home wiring became functional and liberating instead of deadly. Yet it all started with Edison's forward-thinking vision of lighting homes with electricity, despite some major early missteps. Ultimately, his revolutionary wiring system lit the way for profound home design and lifestyle improvements that still benefit us today in the electrical age.