The answer to 'how long does water heater installation last' is that a properly installed water heater can last 8-12 years on average, with proper maintenance. The lifespan of a water heater depends on factors like the type of water heater, the quality of the installation, and how well it is maintained over time.
Water heaters that are installed correctly by a professional plumber and receive regular maintenance like flushing the tank and inspecting the anode rod can often reach the upper end of that lifespan range. Proper installation and maintenance help prevent issues like sediment buildup, corrosion, and leaks that can shorten a water heater's lifespan.