It's a great question! You might think a metal bench in full sun would become unusable, or that a wooden one would quickly crack and fade. Thankfully, modern park benches are engineered to handle these exact challenges. The secret lies in material science and smart design.
First, let's talk metals. Today's metal benches, often made from aluminum or steel, are almost always protected by a powder coating. This isn't like old paint; it's a dry powder electrostatically applied and baked on, forming a thick, resilient shell. It resists UV rays that cause fading and provides a thermal barrier, so the surface stays cooler to the touch than you'd expect. The metal itself also expands and contracts without warping.
For wood, thermally modified timber or high-density hardwoods like Ipe are common. The thermal modification process bakes out the sugars that attract insects and makes the wood dimensionally stable and less prone to splitting in dry heat. These woods, along with options like recycled plastic lumber, are also treated with UV-inhibiting sealants that fight discoloration.
Perhaps the most heat-resilient are benches made from 100% recycled plastic lumber. This material won't rot, splinter, or require painting. It does get warm in direct sun, but its color is molded throughout, so it never peels or fades. Its flexibility allows it to handle temperature swings without becoming brittle.
Finally, design plays a role. Many benches feature slatted designs that allow air circulation, preventing heat buildup. Strategic placement under tree canopies or with integrated shade structures also dramatically reduces direct solar exposure, prolonging the bench's life and comfort.
So, while no bench is completely impervious, through advanced materials and thoughtful urban planning, today's public seating is built to offer a reliable spot to rest, season after season, even under the summer sun.