That's an excellent question! A rusted-out bottom is the most common reason metal trash cans fail, but it's totally preventable with some simple maintenance. Here’s what I’ve found works best from experience.
First, start with a clean, dry surface. Empty the bin and give it a good scrub with warm, soapy water to remove grime and acidic residues. A stiff brush works wonders. Rinse thoroughly and let it dry completely in the sun—this is crucial. Any moisture trapped will start the rusting process.
The single most effective step is to create a waterproof barrier. Once the bin is bone-dry, apply a generous coat of a rust-inhibiting spray paint or a clear waterproof sealant specifically designed for metal. Pay special attention to the bottom, the lower sides, and any seams. Reapply this coating once a year, ideally in dry weather.
Using a plastic liner bag is non-negotiable. It acts as the primary shield between wet waste and the metal. For extra insurance, consider a heavy-duty, waterproof liner or even a dedicated plastic bin insert. This catches leaks and makes cleaning spills much easier.
Where you place the bin matters immensely. Never let it sit directly on damp soil or concrete, which traps moisture. Elevate it on a stand, bricks, or a pallet to allow air circulation underneath. Try to keep it under an eave or in a shaded area to protect it from constant rain and sun, which can break down coatings.
Finally, make a habit of checking for minor chips or scratches in the paint and touching them up immediately before rust can take hold. A little preventative care saves you from having to replace the entire bin down the line. Stick to this routine, and your metal can will last for years!