Picture rail traditionally features a relatively basic design. It's hung 1 to 2 feet (30.5 to 61 centimeters) below the ceiling and is approximately 1 inch (2.5 centimeters) wide, though larger versions are also available. Depending on the style of the room, picture rail can be used alone or combined with crown molding and other trim units. Square or rounded picture rail is the most common, though dentil trim is frequently used in federal or classical design. Dentil trim is composed of a series of equidistant squares or rectangles across the surface, which creates a distinctive look.
Traditional picture rails are equipped with small hooks that can be used to hang pictures or paintings. The picture rail helps to frame the paintings while concealing or eliminating ugly nails and fasteners. While modern picture rail can still be used for hanging pictures, it primarily serves a decorative function by complementing specific design styles. It can also be used as a simple tool for breaking up large wall areas or separating different types of wall finishes.