What decking and joist spans should be used when designing my redwood deck?
  Construction Heart or Construction Common 2x6 decking should be nailed to joists which are spaced no more than 24 inches on center. Joist spans vary according to the dimension used and the joist spacing. For example, typical 2x8 Construction Heart joists spaced 24 inches on center can span 8 feet 9 inches between support beams.

Suggested Joist Spans

Joist size Joist spacing Joist span
2x6 16 inches on center
24 inches on center		 7 feet 3 inches
6 feet 0 inches
2x8 16 inches on center
24 inches on center		 10 feet 9 inches
8 feet 9 inches
2x10 16 inches on center
24 inches on center		 13 feet 6 inches
11 feet 0 inches

Extra weight on the deck surface, such as large planters, hot tubs or spas, will require additional support.