Do you think the building inspector will fail it? If so, there’s no problem - as the GC will have to fix it. If it passes inspection, then it’s me just arguing with the GC.
What would be the remedy now? Those plywood “supports” are glued to the joists, so they aren’t coming off. Maybe put another layer of plywood (this time continuous around the hole) and glue/screw that to the existing joist/plywood?
The building inspector may pass it as they often miss seeing items of importance. Passing the inspection is not an indication that something was done correctly.
The remedy is the same as before. For your peace of mind and the structural integrity of the floor framing, have it designed properly by a qualified professional…or don’t. It’s is up to you.
Or, if it’s difficult to have the plywood continuous around the hole, maybe notching another piece the other way, and sliding it under? Sort of like a U and an upside down U overlaid on top of each other.
The problem is that the weakened area over and below the pipe penetrations will be helped very little by the plywood on either side of the opening, even if the plywood extends many feet along the joist. I’m not attempting to offer a design here, but the best engineered solution will likely be metal plates on one or both sides of the joists that will likely require pipe removal (easy) for installation.
Sorry, no medal. A structural engineer will see only his part of the work, while an architect has a full overview of the entire project, including the structure.
Maybe those joists would have a prayer of holding if significant steel bracing were applied to them, and by that I mean hot-rolled steel angles as big as the pipe will allow, on all four corners of the joists, extending from support to support. Anything less than that is wishful thinking. The angles will have to be engineered before any installation is attempted.
Failing that, the only cure would be to remove the piping, sister the joists with new joists of the same size extending from support to support, and reroute the piping below the joists, or redesign the layout so that the piping runs parallel to the joists. Both the plumber and the general contractor should have known better than to try such a stunt. No matter how much plywood you stick on the sides, it ain’t gonna help.
What you see as the “ground” is actually the ceiling that the joists are supporting, or were, until they were compromised. This is an attic that’s being finished.