Also known as a picture frame or racetrack, a border is generally a decorative strip of one or more boards that run along the outside edge of the deck.
A border is usually done in an identical or accent color to the main decking area, either for aesthetic reasons, or to allow the decking to run over the top edge of the framing and fascia, while also hiding the unsightly cut ends of the deck boards.
Corners where border boards meet are often mitered to continue the smooth, finished edges of the deck boards without having a board end cut visible.
While it requires more work, borders can also be configured on stair treads, when not using fascia boards to cover the sides of the stair and cut ends of the deck boards. This configuration is especially useful on stairs where railing and side fascia is not necessary or practical, and creates a clean edge on the end of each step.
Considering the higher cost of some artificial deck boards, borders can be strategically used to minimize decking cutoffs while maximizing deck size. For example, on an 17 foot wide deck, instead of buying all 20 foot deck boards and throwing away 3 feet from each board, 16 foot boards could be used with a double-wide border run along the outer edge. The double border, at approximately 11 inches wide on each end of the deck, covers an extra 22 inches of the width of the deck, leaving only a few inches of cutoff material on each deck board.
