Copings may be stone, wood or metal. Copings are like the edging of the icing on a cake. It makes the cake look pretty, but it also forms the junction of where two edges meet. Most people have only the foggiest idea of what aluminium copings are, and would not really care if you explain it to them. But, copings are more than simply a way to keep the edges looking neat. They play important functional roles you should think about whenever you look at your exterior walls, driveway, or pool.
The environment can have a big impact on anything outdoors. Take the structure of a garden wall, for instance. Water and dirt can weaken concrete or stone if they get into the crevices. Aluminium or other coping on an exterior wall serves as a cap that keeps water and debris from getting in, at least from the top and sides. Protecting the structure from the elements can make it last longer without any problems.
Most structures will have sharp edges that need rounding off. They could injure someone otherwise. A concrete skating ramp, for instance, will have many edges that may be quite sharp. Putting aluminium copings all around the edges of the structure keep them nicely rounded and safe.
One of the more obvious functions of coping is to separate one element from another. Copings keep an area organised. In the case of pool coping, for example, it separates the pool itself from the pool deck by serving as a frame. Some people may argue that this is only for visual appeal, but that is like saying an interior wall separating the kitchen and dining room is only for decoration.
Copings are an important part of many structures in both form and function. Many materials aside from aluminium are appropriate for copings. Aluminium copings just happen to popular because they are easy to work with and cost-effective.