Which type of insulation is most commonly used for electrical wiring in residential structures?

PVC (Polyvinyl Chloride) is the most commonly used type of insulation for electrical wiring in residential structures due to its excellent balance of properties that suit electrical applications. PVC is durable, resistant to moisture, corrosion, and many chemicals, making it an ideal choice for the diverse environments found in residential settings. It also provides good mechanical strength, which helps to protect the wires from physical damage during installation and use.

Additionally, PVC insulation has good electrical properties, including low electrical conductivity and the ability to withstand high temperatures, which helps maintain safety standards in residential wiring. Its flexibility allows for easier installation around corners and obstructions, further enhancing its usability in home wiring systems.

While other materials like rubber, fiberglass, and polyethylene are used in various applications, they do not offer the same level of versatility and suitability for the wide-ranging requirements of residential electrical installations as PVC does.