It is a good idea to construct a pergola on your own if you are wanting to save money. But there are some intricate, significant points that are more familiar with a contractor. For instance, if a pergola is constructed with wood, it is very important that the wood is treated. Untreated wood has humidity in it, which tends to damage the wood in a short span of time. For wood pergolas nails are not as good as screws in holding the wood together, wince they can pop up from the surface. Screws are much better and some particular types of lumber materials are good. A contractor can help guide you in deciding upon materials.