What type of wire insulation is most commonly used for indoor residential wiring?

Polyvinyl chloride (PVC) is widely used for indoor residential wiring primarily because of its excellent balance of performance properties, including durability, chemical resistance, and cost-effectiveness. This type of insulation is not only resistant to moisture and corrosion but also provides good electrical insulation, making it ideal for protecting conductors in a residential setting. PVC insulation is flexible, which allows for easy installation and manipulation of wiring within walls and ceilings.

Unlike other materials, PVC is particularly favored for electrical applications because it can withstand a range of temperatures and is less prone to cracking compared to materials like rubber. It also adheres to safety standards set for electrical wiring, ensuring that installations meet necessary regulations. The familiarity of electricians and contractors with PVC further supports its widespread adoption in homes.

Other insulation types, while used in specific contexts, do not offer the same combination of properties that make PVC the preferred choice for residential wiring. Rubber insulation, for instance, may be used for specific applications due to its flexibility but is less common in standard home wiring due to its cost and the availability of superior alternatives.