How do I correct free-standing deck moving away from home?

Question

I have what is primarily a free-standing deck (18x22) in the back of my house. I say "primarily" because I did nail into the ledger board underneath my glass sliding door, but only there. The rest of the deck is floating and I did this only to ensure the deck was flush with the house.

The deck has been up for about 7 years, but recently it is begun to move away from the house a bit, by about an inch or two. The board underneath my glass sliding door (that was there before the deck was installed and that I nailed onto) is now pulling away with my deck. One of the main support beam for the deck that rests about a foot from the house has begun to tilt as well.

My question is, how should I best correct this before it becomes a major problem?

I would add that I think more recently (past year or two), the ground became soft due to some of the dirt around the footings settling, and allowing water to pool there and soak into the ground. I've since corrected that.

My thought was to use lag bolts through the siding and to the rim joist of the house over the full 22 foot length, to prevent any further movement away from the house, and possibly trying to "pull" it back to the house with some external leverage. Of course the deck isn't small, so I thought maybe a few turns of the lag bolts every week or so from inside the house might help bring it in.

There is siding between the rim joist and the deck (and probably about 3 inches space between the deck joist and house rim joist), so I would drill right through the siding and then caulk it to prevent moisture going behind the siding.

Is this ridiculous, or am I on the right track? Any assistance or suggestions are appreciated!

Answer 1

This is one of the reasons free standing decks are not a good alternative to a deck that has been engineered, permitted and structurally connected to the house.

Using the house to fix what is, essentially, a foundation problem with the deck will not necessarily go well. It is not likely that all parts of the deck moved away from the house equally (structures don't usually "slide" around.) It is more likely one side has dropped opening a gap on the house side. This is common, and can usually be fixed by jacking the outside edge back to its original position.

Worse case you will need dismantle and rebuild the deck, sitting it on proper foundations constructed below the front line, and anchoring it to the home's rim joint.