Accuracy is crucial when laying out a new deck. You wouldn't want all of your hard work to be thrown off by a few wrong measurements. That's why it's important to lay out the deck before you start building. You'll have the chance to check—and double check—all of your measurements before you begin. To make the process even simpler, we've designed a deck with several fail-safe features. The beams, for instance, may be off by an inch or so without weakening the structure.
Before you begin, produce an accurate scale drawing and get it approved by your building department. Keep in mind that the decking will overhang the joists by 1-1/2 inches or so on all sides. You'll also need to plan out the footings and beams. Because they extend 3 feet beyond the footings, massive beams made of three 2x10s are required. Large beams call for larger-than-average supports—4x6 posts and 12-inch-diameter footings.
Expect to spend four to five hours building batterboards, figuring out the layout, stretching lines, and determining footing locations. To lay out the deck, you need to be able to measure and check for square, fasten screws, and pound stakes. It's also a good idea to double-check your drawings for accuracy once they've been approved, and to study the way the deck will be assembled.