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We had a new deck built by contractors, and have a few concerns on what I might need to fix, or have them come back to repair:

  1. Looks like a mistake/mismeasurement here, but is it alright to lean a second post on the footing to correct it?

  2. I don't see joist tape used anywhere across seams, how likely is this to cause problems?

double post footing

  1. I understand every footing doesn't need to be level, but this example seems extreme. Is there a recommended maximum grade for footings?

unlevel footing

  1. A portion of the deck has a massive rock protruding underneath, which is difficult to build on top of. These joists are 2x4 however, which seems to me will struggle to support the weight. The piece of 2x6 also is not sealed and is resting on the stone. Will this cause issues in the near future?

2x4 joists 2x6 support

  1. The joists sitting across the box frame are sitting on top without being attached. They are attached on another portion of the deck (see first image). Is this fine if they are attached elsewhere?

loose frame

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Your beam to post connection looks way under-designed. In your first image, I see two fasteners holding up what looks like a 2x12 (plus a couple of nails--I'm betting 10d from a nail gun used to hold everything in place for final fastening). Given the 40 psf live load for decks and a contractor friendly 50 square foot tributary area for the 2X12, I compute a 2000# total unfactored live load and therefore 1000# unfactored live load per connection.

Assuming Doug Fir (a relatively strong softwood), a 3.5" post, a 1.5" beam, and a 5/16"x4" lag screw, the NDS's connection calculator, https://awc.org/calculators/connection-calculator/, spits out the following strengths per fastener:

  1. Im 1427 lbs.
  2. Is 680 lbs.
  3. II 458 lbs.
  4. IIIm 471 lbs.
  5. IIIs 279 lbs.
  6. IV 248 lbs.

Each of these modes corresponds to the single shear connection modes from the following: Connection Yield Modes

This suggests a 500# connection strength for resisting 1000# unfactored live load, and that's without any dead load considered.

It would be inappropriate to include the strength contribution of those two 10d nails (best guess that they're 10d nails) if they're not hot dip galvanized, but assuming they are, that NDS calculator spits out a mode IV strength of 203# each, so that would bump up the connection strength to about 900#, which is still short of what I consider a load friendly to the contractor because of my low estimate of the 2X12's tributary area.

My analysis was based on LRFD strengths from the NDS calculator, but I didn't amplify the live load with the LRFD's customary load factors. The load combination with 1.6LL would probably govern, bumping the demand up from 1000# unfactored to 1600#. Technically a contractor could invoke ASD instead of LRFD to arrive at different numbers, but LRFD is more contractor friendly in my experience. Basically you've got at least 1600# of demand and 500# to 900# of capacity.

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