I'm building a freestanding 14'x14' deck and would like have approximately 2' of joist and beam cantilever to avoid digging posts around buried utilities. What's a little confusing is how interior posts play into the max calculation of overhang. When I review the deck construction guide: [url]http://www.awc.org/pdf/codes-standards/publications/dca/AWC-DCA62012-DeckGuide-1405.pdf[/url] It's pretty clear that the max overhang is 1/4 of the beam or joist span. [ATTACH]82071[/ATTACH] Am I reading this correctly that maximum overhang would be achieved with fewer posts spaced as far apart as possible? In other words, if I only had a total of 4 posts on each corner, I'd be maximizing my span. It seems like for every extra post you add between outside edge posts you're decreasing your beam and joist span, and thus decreasing your max overhang.

The T1-11 is rotten right next to the 2X6 FLOOR of the deck.I took up one of the top 2X6 and theT1-11 is rotten from the supporting 2X6 going down behind the supporting 2X6. I was thinking cleaning out all the rotten wood and then using the foam (red can) to spray down were the t1-11 is rotten. I can not get to the bottom.From what I can dig out, it is rotten about 2-4 in down. I would then use a 1X3 board to fill in were I cut the bad t1-11 siding out. The T1-11 siding goes to bottom of the supporting 2X6. At thee bottom the siding is still good. I have enclosed some pictures . The question is the red can of spray foam good enough to last 5-10 years to seal were the rotten wood was. At my age I will let my son think about what to do then.