The answer to 'lifespan of switch' is that the average lifespan of a light switch in a residential home is 10-20 years. Switches are relatively simple devices, but they can wear out over time due to repeated use and exposure to environmental factors like dust and moisture. With proper installation and regular maintenance, a high-quality switch can last for 15-20 years or more. However, cheaper or lower-quality switches may only last 8-10 years before they start to fail or become unreliable.
It's important to replace any switches that are no longer functioning properly, as faulty switches can pose a fire hazard or lead to other electrical problems in the home. Homeowners should also consider upgrading to more modern, energy-efficient switch models when replacing older switches.