The Complete Handbook of Lamp Post Bases

Chapter 1: Understanding Lamp Post Bases

The lamp post base is the transition piece between a buried, concrete foundation and the above-ground luminaire and pole assembly. Its job is simple in concept: to transfer wind, seismic, and weight loads from the pole and luminaire down into the ground, and to protect the electrical splice from water, insects, frost, and impact. In practice, executing this simple concept is surprisingly complex. A base that is under-specified for its application can corrode from the inside out, leak water into the junction, or fail to hold the pole level in a moderate wind. Understanding exactly what the base is and how it does its job is critical to choosing one that will perform safely for its full design life, which is usually expected to be twenty to thirty years or more.

Core Components of a Lamp Post Base

A lamp post base is not a single piece of metal; it is a precisely manufactured assembly of integrated features. Most residential and light-commercial bases are cast from aluminum or fabricated from stainless steel or galvanized steel plate. Regardless of material, virtually every base on the market performs its job through the same fundamental components: the mounting flange, the bolt circle, the access door or handhole, an internal splice chamber, and a top collar that accepts the pole or fixture.

The mounting flange is the flat, wide ring at the bottom of the base. It does the main work of transferring load from the top of