Short answer: yes, a street bench placed in the shade will usually last longer than one in full sun, but the full picture depends on material, moisture, and airflow.
Sunlight is hard on outdoor furniture. UV light breaks down wood fibers, plastics, and paint. You’ll see it first as fading or chalking, then as fine cracks. Heat is just as tough: materials expand and contract every day, which loosens bolts, warps boards, and opens tiny splits where rainwater can get in. Timber in direct sun also dries unevenly—top and sides shrink faster than the underside—so it cracks and splinters sooner. On metal benches, the heat can make the surface too hot to touch and speeds up corrosion around scratches.
A shaded bench avoids the worst of that. It stays cooler, fades more slowly, and doesn’t go through such extreme daily movement. Compare two identical wooden benches in the same park, and the shaded one generally keeps its color, finish, and tight joints longer. Plastic benches in shade are less likely to turn chalky or brittle, and painted metal benches hold their coating better.
The catch is that shade is not always friendly. Under dense trees, a bench can stay damp after rain or morning dew. That invites mold, mildew, moss, and wood rot. Leaf litter, sap, and bird droppings sit on the surface and stain or speed decay. A metal bench in damp, still shade can rust once its coating gets chipped. So a cheap pine bench in deep, soggy shade might fail faster than one in dry, sunny air.
The sweet spot is usually partial shade with good airflow. Morning sun dries off dew; afternoon shade blocks the harshest UV and heat. Good drainage underneath and occasional cleaning do more for longevity than simply hiding the bench from the sun.
If you’re choosing a spot, put the bench in the shade if you can, but don’t tuck it into a damp, overgrown corner. Keep it dry, clean off tree debris, and let air move around it. With reasonable maintenance and the right material—teak, cedar, powder-coated aluminum, or high-density recycled plastic—a shaded bench will usually give you several more years of good looks and solid structure.