Hey, that's a great question! The average lifespan of a typical metal outdoor trash can really depends on a few key factors. Generally, you can expect a well-made metal bin, like one made from galvanized steel, to last anywhere from 10 to 15 years. Some heavy-duty models might even push past that with proper care.
The biggest enemy of a metal trash can is rust. If you live in an area with lots of rain, snow, or high humidity, the lifespan might be on the lower end of that range. Constant exposure to moisture will speed up corrosion. The quality of the metal and the protective coating are also huge factors. A cheap, thinly coated can might only last 5 years before it starts showing significant rust, while a premium, powder-coated one will hold up much longer.
To get the most out of your can, place it in a somewhat sheltered spot if possible, like under a porch eave. Also, make sure to clean it out periodically with mild soap and water to prevent grime and acidic residues from eating away at the finish. So, while 10-15 years is a good benchmark, your specific climate and maintenance habits will ultimately determine how long it serves you.