Last year, the American Wood Council updated its Prescriptive Residential Wood Deck Construction Guide - commonly referred to as DCA 6 - to conform with the 2012 IRC. Now the AWC has released an updated version that includes a new commentary section with example calculations for the various sections and tables in DCA 6. There's also a new tributary area appendix that describes an alternative method for calculating loads on posts and footings, which should allow most deck builders to use taller posts and smaller footings than when following the Guide's more conservative Table 4. The new guide is available for download here.