Though out here on the West Coast we're running out of nice, flat building sites, homeowners still need some level outdoor space. Where there's no hope for a backyard, the solution is often a deck. Even on flat sites, a deck provides a civilized separation between the building and the grass. When the outer edge of the deck is supported by a girder, the joists are ordinary beams (Sketch A). They follow the expected laws for simple beams with uniform loading, so you can select the proper joist sizes by looking them up in the tables. A simply supported beam has a single point of maximum bending stress, right at the center of the span. This is