Abstract: A fence assembly including a post and interconnecting rails. The post includes an interior chamber structure defined by numerous compartments, an exterior wall structure and a plurality of inwardly projecting rail-receiving channels. The rail-receiving channels at least partially define the geometry of the interior chamber structure. The assembly may be made of extruded plastic material such that the post, rails and additional components, such as channel inserts, are generally hollow along their respective elongate dimensions. Each of the components within the assembly may be cut to user-defined lengths. The purpose of the abstract is to enable the United States Patent and Trademark Office and the public generally to determine from a cursory inspection the nature and gist of the technical disclosure, and is not to be used for interpreting the scope of the claims.