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I am planning a potential DIY job for a new deck that I want to put on my house. This is roughly what I think we want

enter image description here

The house is roughly 36' long and the garage roughly 22'. The door from the house is actually only about 15-16' from the outside corner and I want the deck to come about 11' down the back before the stairs come down from there.

The door is on the first level of the home above the rear exposed basement wall, so roughly 1 story high. The house sits on a hill that slightly grades upwards towards the garage at roughly a 12/3 pitch, so the stairs will only be a half flight.

I am variable on how far outwards roughly I am comfortable with the deck extending from the house.

My question is, what would be the optimum layout for posts and beams to properly support this deck? (Assuming that edges of the deck touching the building will be bolted to ledger boards) I have built a simple square deck before but never anything with outside and inside corners and variable length.

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Design-wise (both aesthetics and engineering) I'd maybe consider not having that inside corner and just extending the deck out so it's all even. – DA01 Feb 14 '13 at 20:20
@DA01 That is a good consideration actually, it might make everything more structurally sound... I wonder though how far of a joist span would be acceptable beam to ledger board? – maple_shaft Feb 14 '13 at 20:22
That depends on the dimensions and type of lumber of your joist. – RyanWinchester Feb 14 '13 at 20:24
@decker Definitely 6x6 posts and tripled 2x12's for the beam. Joists are probably going to be 2x10, all wolmerized dimensional lumber – maple_shaft Feb 14 '13 at 20:27
@decker I always like to overkill when it comes to supporting a structure... plus I have a lot of obese friends ;-) – maple_shaft Feb 14 '13 at 20:43
up vote 6 down vote accepted

Blue Dashed Line: Your 3-2x12 Beam

RED X: 6x6 Posts

Deck with beams and posts

  • D.Fir 2x10 @ 16" O.C. spanning 14' + 2' overhang past beam: 16' joists
  • Solid 2x10 Blocking mid-span
  • 6x6 posts @ 12' O.C.

*post edited to match additional info from comments.

share|improve this answer
How long do you think is too far for a single beam? What is an acceptable joist span length in your opinion? – maple_shaft Feb 14 '13 at 20:25
Depends on type/species of wood. Do you know what type of lumber is the most commonly used for pressure-treated in your area? – RyanWinchester Feb 14 '13 at 20:28
@decker good God man... wth were you building?! – maple_shaft Feb 14 '13 at 21:00

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