Iam building a deck twevle feet in the air and iam wondering how fari can go inbetween supports.?

Question

iam using 2/12 lumber

Answer 1

put the post, 6x6, on 8' centers....u didnt state the size of the deck....then band the outside with (2) 2x12.....then set ur griders, go with a drop grider system, and install ur joist....i really need to know the size of the deck to answer this better...email me....

lic. gen. contractor

Answer 2

You need to consult with a professional that knows the span tables for dimensional lumber.  The elevation of this deck will be of some concern relative to wind, sway, stability and safety.  You'll need to engineer post pads and sway bracing as well.

Mike Lonergan

TradesProfessional, Inc.

Answer 3

it wont matter how tall you build it... but what matters is  the wind factor .....     if you useing 2 /12 that alot of weight .. to hold up 12ft off the ground .......

  i would use a support every 6ft apart ......

  and use bolts instead   of nails  ...

  cross supports  really help here   to prevent  a buckling affect

Answer 4

Something this tall I would have it professionally built you have alot of factors with something like this and I doubt you want to fall off of it or is crumbling to the ground.  I would say however

6ft max between supports.  use 6x6posts and in atleast 4'of cement something this high I would mount in cement in ground rather then just a top mounting device.  Really though maybe get a few quotes from contractors or even some ideas from them most will come give free estimates and share some ideas on whyat would work.

Answer 5

It is the depth of your joists (the beams connecting the supports) that dictates the distance between supports.  Generally for a home deck you can put supports on 8' to 10' centers if you use double 2 x 12s for joists.  I use Redi-rod and put one joist on each side of the supports with two 1/2" redi-rod bolts all the way through and use big washers with double nuts on each side.

With a deck built this high, however, I would be more concerned about "sway".    I would use at least rough, full-dimensioned 6" x 6" supports anchored in concrete and at least 3' in the ground.    Furthermore, I would use 2"x6" angle supports from 4' out on each joist back to each support and 4' below the joist.    I would do this in both directions -- although not necessarily at every post.  Certainly use the angle braces at each corner and the center post on each side, depending on the total size of your deck.

Also note that with a deck this high, most building codes will have a requirement for a 48" high railing with vertical or chainlink fill in.  Don't use horizontal boards between the handrail and the deck because children climb on them and fall over the hand rail.

Good luck with your project.