The answer to 'how long does electrical wiring last' is that properly installed and maintained electrical wiring can last for decades, often 30-50 years or more. The lifespan of electrical wiring depends on several factors, including the quality of the initial installation, the type of wiring used, the environmental conditions, and the amount of use and wear over time.
Copper and aluminum wiring, when installed correctly and protected from damage, can last a very long time. However, older wiring materials like knob-and-tube or cloth-covered wiring may need to be replaced sooner, as they can become brittle and pose fire hazards over time. Regular inspections and maintenance by a licensed electrician can help ensure the safety and longevity of your home's electrical system.