Whenever the subject of flashing deck ledgers comes up a fair number of replies suggest making the deck free standing. I understand in the abstract how this might be a good idea, but has anyone here ever built, or for that matter seen, a free standing deck more than a couple of feet above grade that handled the required bracing without looking like hell?
I’m still on the fence as to whether this is a good idea or just a nice idea (if you get the distinction).
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I've seen some very tall hillside back decks in seismic areas that, while not freestanding, had so much diagonal bracing at the projecting side that they could have been built freestanding in most other conditions. A lot of them had lattice panels hiding the structure underneath.
It wouldn't work over a back patio, but over an unused hillside, the lattice looks fine if put up with half an ounce of care.
You can also use engineered hardware and solid members or careful bolting schedules to acheive the rotational strength.
k
Engineered moment connections might be the way to go. I hate lattice for a variety of reasons: It creates a not inside not outside nasty space under the deck, it usually looks quite obvious that you put it there to hide something, it gets damaged or rots close to the ground... it's not simply fluke it only gets used under decks.
My criteria for going to a free standing deck would be that it did not cause more problems, both visually and in its construction, than it solved by not having to properly attach a ledger - something I don't find that hard in new construction. I can imagine it might be the way to go in renovations, but for something everybody seems to think is a good idea, there sure aren't a lot of built examples out there.
Yes, up to 12' high on hillside.
I kept the support posts back 2-3 feet and cantilevered over them, then cut curved knees to function as decorative corbel style.
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That sounds like what I'm looking for. Some one who has actually done it. Any chance of pics? I really liked the threaded post supports you use on some shorter decks on rock.
Photos would take monumental effort. both of the ones I did here were before digital. Would almost take a threat of lawsuit to get me to dig into that file drawer for print pictures.One has since been closed in for lawn mower and firewood storage place, and I have not been to the other place in many years. They had another crew rebuild the foundation 2-3 years ago, so I'm not even sure if things are still there the same on that one, but I could probably sneak in with a camera and look.
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No problem with the pics. I have only managed to post links to ones I find on line. I seldom take pictures of anything I do and can't seem to post the few I have.
Think 'skirting'.
There are three variations on this theme:
1) A totally unattached deck, though perhaps inches from another structure.
2) A deck which is totally self-supporting, but which has a horizontal tie of some sort (perhaps a ledger that's slotted on the lags to "float" vertically) to the neighboring structure for lateral support.
3) A deck which is more or less conventionally attached via ledger, but which also is supported below by posts, etc, so that (in theory) no weight bears on the ledger and the deck would not fail were the ledger to come unattached.
#3 is probably the simplest -- you just add a row of support posts 2-3 feet from the neighboring structure, then build pretty much as you would for an attached deck.
Sorry, I've built/designed two, but neither was more than 18" above grade. Both were cases where I needed to "get someone started" on building their deck, and in both cases I knew I could get out of flashing it (or handholding through the whole process) if I showed them how to do it freestanding.
From where I stand, here in the wet part of a wet state, I'm starting to think that either extended eaves or a porch roof ought to be the first consideration in deck building... Flashing ought to be the second line of defense out here!
But, I'm interested in the discussion - Piffin, why did you build the freestanding deck structures you built? It's not like you need help in figuring out a tricky flashing detail. I'm assuming there was structural reason driving it?
-t
Never done it and it would be expensive for a deck, but having holes bored deep with sono tube above and steel reinforced concrete seems like it would work with no diagonal bracing.