The answer to 'how long does dimmer switch last' is that a typical dimmer switch can last for 15-20 years with normal use. Dimmer switches are designed to withstand frequent on/off cycles and the heat generated from controlling the flow of electricity. However, the lifespan can vary depending on factors like usage, wiring, and environmental conditions.
Proper installation and avoiding overloading the dimmer switch are key to maximizing its longevity. It's also important to check for any signs of wear or damage, such as flickering lights or a warm switch, and replace the dimmer if needed to ensure safe and reliable operation.