Electrical fires have been a major problem plaguing homes for over a century. Many of these fires could have been easily prevented with a simple change to home electrical wiring that was proposed in the 1930s. This proposed change involved switching from using cloth-insulated wiring to more fire-resistant rubber-insulated wiring. Had this change been widely adopted at the time, it would have saved thousands of lives and prevented immeasurable property damage over the following decades.

The Dangers of Cloth-Insulated Wiring

In the early 20th century, most homes were wired using cloth-insulated copper wiring. This type of wiring had a braided cotton or cloth insulation covering the inner copper conductor. While common, this cloth wiring posed serious fire risks.

The natural fibers used in the insulation were flammable and prone to deterioration over time. Fraying and cracked insulation often exposed the inner electrical wires. This allowed arcs, sparks, and extreme heat to ignite surrounding materials.

Cloth wiring lacked the fire resistance of modern wiring. Once ignited, the flames and heat could spread quickly through the walls via the wiring. Older homes wired with cloth contained a virtual highway for fire spread behind the walls.

The dangers of cloth-insulated wiring were well known in the electrical industry by the 1930s. Insiders and experts called for upgrades to more reliable rubber or plastic-insulated wiring. However, cost concerns and lack of regulation allowed cloth wiring to remain dominant in homes.

The Safer Alternative: Rubber-Insulated Wiring

Rubber-insulated wiring was a readily available alternative to cloth-insulated wiring by the 1930s. This type used rubber insulation over the inner copper conductor rather than cotton or cloth.

Rubber insulation was inherently more fire-resistant and durable than the natural fiber cloth coverings. It did not deteriorate or fray over time. This helped prevent exposed wires that could arc and spark.

Furthermore, rubber insulation was self-extinguishing and did not allow flames to spread rapidly. When ignited, the flames self-extinguished rather than engulfing the wiring. This contained electrical fires and slowed fire spread.

Switching to rubber-insulated wiring as the de facto home wiring standard in the 1930s would have prevented untold numbers of electrical fires. The superior fire resistance and durability of rubber could have saved thousands of lives and millions in property damages.

Efforts to Transition Away from Cloth Wiring

By the 1930s, electrical and insurance experts were actively campaigning for the replacement of old cloth wiring with newer rubber-insulated wiring. They recognized the inherent fire dangers of the outdated technology.

Starting in the late 1920s, underwriters and insurance groups lobbied for national electrical codes to prohibit cloth wiring. Local ordinances banning its use in new construction cropped up. However, cost concerns slowed efforts to regulatecloth wiring out of existence.

Manufacturers resisted costly transitions away from cloth wiring production. Builders lobbied against wiring regulations that would increase home construction costs. With no national electrical code in place, cloth wiring persisted.

Lack of coordinated action on wiring regulations was a missed opportunity for preventing countless avoidable electrical fires. More robust regulation and fire-safety oriented building codes could have saved lives.

Lasting Impact of Legacy Cloth Wiring

By avoiding a switch to safer rubber-insulated wiring in the 1930s, a ticking time bomb of fire risk remained in homes for decades to come. Outdated and deteriorating cloth wiring continues to pose fire risks today.

It is estimated over 10 million homes in the U.S. still contain obsolete cloth-insulated wiring. This old wiring accounts for around 25,000 house fires per year.

Replacing legacy cloth wiring with modern wiring remains a significant expense for many homeowners. Without large-scale wiring upgrades in the 1930s, fire and electrocution risks persist today.

Loss of life and property to electrical fires could have been greatly reduced with the simple solution of new wiring standards. The home wiring decisions made decades ago have ongoing consequences by allowing preventable electrical fires to remain common.


The switch to rubber-insulated electrical wiring proposed in the 1930s could have profoundly improved fire safety in American homes. Cloth-insulated wiring posed a known danger that persists today. Wiring upgrades may have seemed costly and inconvenient at the time, but would have saved thousands of lives and prevented immeasurable damage over generations. This serves as a powerful lesson on adopting safety advances proactively rather than reactively. Home wiring may seem like an invisible infrastructure issue, but reforming standards could have benefited countless families across the country.