A rail joint bar for use in an insulated lap joint assembly includes a longitudinal extending body defining a plurality of holes therein for receiving fasteners. The body has a first end and a second end positioned at opposite ends of the body relative to a longitudinal direction of the body. The body is bent forming a first portion adjacent to the first end, a second portion adjacent to the second end and spaced from the first portion in the longitudinal direction, and an intermediate portion defined therebetween and positioned between the first and second ends. The first portion and the second portion are substantially parallel to each other and, and the intermediate portion of the body is configured to accommodate an increase in thickness of a web section at a point where two railroad rails are joined.