Elevated Deck Design

[PatrickMcQuillen]

I am looking to build a deck on the back of my house. The house is on a hill and has a sliding glass door from the basement to the back yard. There is also a sliding glass door from the kitchen to where the deck will be. I am having conflicted ideas of how to go about designing the deck.

The basement wall is 96" from the ground of the back yard to to top of teh poured concrete, there is then two 2x4's with a double 2x10 on top. There as about 12" from the top of the basement sliding glass door to the top of the poured foundation. There is then about 15" from the top of the foundation to the bottom of the kitchen sliding glass door.

I am not sure if i should attach the ledger to the foundation wall or attach into the double 2x10s of the house.

I would prefer to attach to the foundation and build a stair at the kitchen door. However when I add the beams at the far end of the deck, i will only have about 76" of clearance to walk under.

I can raise the deck an extra 12" or so by attaching the ledger to the

2x10s. I have concernes with attaching the deck to this section of teh house because it does not appear to be a sturdy as the foundation would be.

Is there any way to attach a ledger to the foundation, but then have the joists run above the ledger somehow?

Thanks for any help & suggestions.

Patrick

[Joe]

Your project is more complicated than you think. You will probably have to pull a permit to build it, so prepare properly and have an architect/engineer whip up a set of plans. In the long run you'll save time and money and get it right. HTH

Joe

[Charles Pisano]

I have to ask. What is there now..? Do these doors open up to a drop off?

[aemeijers]

IMHO, I wouldn't load up the ledger board with any significant weight from a large deck, but rather use it just to tie the basically free-standing deck structure to the house to dampen vibration and twisting. (A large totally free-standing deck that tall can make people stepping onto it from the more-solid house feel like the deck is moving.) Rather than hang the deck joists from a massive ledger board, put another main beam and row of posts to match the one on the yard side, a foot or so back from the house wall, below the joist level. Use the rim joist on the house side as the ledger, held away from house an inch or more with standoffs, to keep siding from rotting, with suitable flashing on the standoffs. As to what level to put the deck- you want the deck 'floor' to be no more than a normal step (a few inches) below the sill level of the sliders. Anything more will require a huge top step for people to stand on to open and close door.

Like I said, IMHO. Unless house wall is framed for the load of a large deck, adding all that weight can do nasty things to wall if deck frost-heaves, or gets a lot of wind load and picks up and starts fluttering like a leaf. Even if wall can take the downward load, sometimes it can't take the sideways loads or vibration from a load-bearing ledger board.

aem sends....