Feature Article - October 2005
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Shed Some Light

How to avoid making costly mistakes when it comes to sports field lighting

By Kyle Ryan


Poles

Why do poles need to be so high, anyway? Well, the taller they are, the better, for several reasons. The light beams can be more targeted on a certain area. There's less light spill into places that don't need or don't want illumination (that is, homes around these fields). Local ordinances that mandate a maximum height for poles actually increase the odds of light trespass (light falling beyond field boundaries).

"The higher you go, oftentimes the easier it is because you can bring the fixture down a little more and target your field better," Good says. "For example, we do high-school football fields. Those will have anywhere 60- to 70-foot poles often, and those you can keep the light from spilling really from out beyond the track. You can do those very, very cleanly. But they're much more expensive systems. It really is a matter of what do you want to do. You can do just about anything, but the cost goes up."

Poles come in a variety of materials: treated wood, aluminum, steel, cast iron and concrete. They are either buried into the ground or mounted to a concrete foundation; the former is cheaper but susceptible to decay, while the latter is sturdier but more expensive. Many designers strongly discourage wood, mostly because it warps over time, requiring the lights to be continually adjusted.

"Typically we go to an aluminum," Good says. "You're not going to have the rusting problem. They're pretty rigid. They actually work very, very well. That'd be my first place. Concrete poles are great, but they're expensive. It's a great option if you can afford it. Steel also works O.K.; it's just I probably lean toward aluminum in those cases because it'd be more maintenance-friendly over its life span. Both the steel and aluminum pole have what's called a 30-year design plan, so within 30 years, it's expected you might have to replace it."

What makes them maintenance-friendly? According to Good, aluminum poles generally come with a powder coating, which protects the material. Steel's biggest problem is its longtime nemesis, rust.

"If you're going to do a steel, there are a lot of places that will recommend powder coating," Good says. "I would say no to powder coating; get a wet paint. It's going to adhere better for a longer time, and it can be touched up easier. Steel is going to rust; that's your biggest problem, and so if it gets scraped up, you have to touch it up, and you can't touch up powder-coat paint. With aluminum, if you scratch that powder coat, it's not a big deal—it's not going to rust anyway."

Both concrete and cast iron face height limitations; they simply can't be manufactured and/or shipped because of their length. Regardless of the pole type, Good recommends paying close attention to the vibration-dampening ability of the pole's material.

"Go ahead and go for a slightly larger diameter pole, something that's pretty stable," he says. "Get vibration dampeners, things like that. Because the less vibration that's in the fixture, the longer it's going to last. As with anything, the more you shake it, the sooner it's going to fail."