That's an excellent question! As someone who specifies and maintains urban furniture, I can tell you that a well-applied powder coating on benches typically lasts between 10 to 20 years before significant wear requires re-coating. However, this isn't a simple number. The actual lifespan hinges on several key factors.
First, the quality of preparation and application is paramount. Benches that are properly cleaned, pre-treated, and coated in a controlled environment will far outlast those with a rushed job. The metal must be free of rust and contaminants before the powder is electrostatically applied and heat-cured into a solid, seamless skin.
Environment is the second major player. Benches in a mild, coastal city will perform differently than those in an industrial area with acid rain or a region with extreme freeze-thaw cycles. Constant UV exposure, salt spray, abrasive dirt, and impact from use all gradually degrade the finish. High-quality powders include UV inhibitors and corrosion-resistant formulas specifically for these challenges.
You'll know the finish is nearing the end of its life when you see fine cracks (crazing), fading or chalking of the color, and eventually, small chips that can lead to underlying rust. The good news? Powder coating is famously durable. It resists chipping better than liquid paint and doesn't peel. With basic annual cleaning using mild soap and water to remove grime and pollutants, you can easily maximize its lifespan.
So, while 15 years is a solid benchmark for planning, investing in high-grade powder coating from the start and placing benches in considered locations can see them looking great for two decades or more, making it a supremely cost-effective finish for public urban spaces.