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Very thorough explanation of the new codes relative to this subject. As a guy who left a structural engineering gig 28 yrs ago to become a GC, one thing about the whole ledger bd thing has confused me for the past 2 decades: who came up with that concept and how did such a poor structural approach get into the codes to begin with? This area has been addressed, amended, changed and otherwise beat to death for the past two decades. The real solution is simple: don't attach a ledger to the house!
The house I grew up in was built in 1911, and it's full length front white oak porch is still intact and sound. The key to that success is something that plumbers and roofers learned long ago - water runs downhill. But yet the deck (it came along about 60 yrs ago) has repeatedly ignored that concept and everybody who builds them pits a ledger against the house and builds the deck level. They drill and bolt until they turn the house ledger into a piece of Swiss cheese then lay their deckboards crossways so water can't run off. This approach also encourages water to splash more aggressively against the patio door. This not only shortens the life of the door but inevitably finds the weak spot in the flashing setup.
So, the simple answer: don't put a ledger against the house.
I've built dozens over the past 2 decades in a very inspection-happy state and none have a ledger board. I slope my framing 1/8" - 3/16" /lf away from the house for floor drainage and the difference in water splash on the patio door is amazing. Also, as water doesn't sit on the boards, even the wood floors stay a lot more stable.
I put a support post against the house and thru bolt it to the wall. The sides are now the load carrying members and they may be the same doubles that would normally be there,occasionally a triple if the span is long.. This also allows a much more rigid railing setup down the sides. The end away from the house might get an extra post, most for rigidity of the railing. Under the codes, it's considered a "free standing deck" and therefore not subject to the continual "lets try something else and see if that will work" issue of the infamous ledger board.
I'm just sayin.....
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