That 10-foot deck I framed last month is already sagging in one corner
I built a small ground-level deck off the back of my house about 5 weeks ago, right before the rains started here in Portland. Used pressure-treated 2x6s on 16-inch centers like every guide says, with joist hangers on the ledger board. The corner closest to the downspout is dipping a good half inch now, and I'm kicking myself because I think I skimped on the footings. I just dug down maybe 8 inches and poured some Quikrete, but the ground here is that nasty clay that swells up when it gets wet. Should I have gone deeper, or is there a way to jack it up and add a pier after the fact? What's the right way to fix a sag without tearing the whole thing apart?