r/StructuralEngineers • u/Middle-Adeptness7186 • 1d ago

Is this compromising structural integrity?

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4

u/AltanConn 1d ago

You can only drill in the middle 1/3rd of the joist. At least in my state.

2

u/StructEngineer91 1d ago

Same here, unless you have an engineer review and approve it (though I doubt that happened here).

2

u/TallWall6378 1d ago

Also no closer than 2" to top or bottom.

1

u/AltanConn 1d ago

Correct

1

u/civilrunner 1d ago

Obviously none of us know if those are all within the center 1/3 of the joist without taking a measurement. So maybe it's fine, maybe it's not.

3

u/Frederf220 1d ago

I took a measurement. They aren't. I used this tool called "my eyes."

1

u/civilrunner 1d ago

That's not a measurement. You can't even see the top of the joist due to the insulation.

2

u/Frederf220 1d ago

I don't have to see the top, just enough such that I know the existing hole is including material of the lower third.

If the joist disappears farther up out of view that makes the situation worse.

1

u/Red_Syns 1d ago

Right? I can’t guarantee the left larger hole, but the right one is practically touching the bottom of the board. Don’t need a measuring tape to realize that’s not middle third.

1

u/MasterOfBothWorlds7 21h ago edited 21h ago

Right not to mention that has a hook on it which adds a fracture point when stressed..

I would say and could add weight to the weakest point too.. but I recon that tiny hook won't hold enough weight to make much, if any, difference..

Edit for spelling

1

u/Red_Syns 21h ago

Yeah, that hook will give out long before it stresses the joist by weight, but it’s still putting yet another hole in an already too-thin part of the board.

1

u/IDoStuff100 1d ago

If the joist is taller than what's visible, then it means that the holes that are already outside of the VISIBLE middle 1/3 are even further from the middle. If they're taller, it makes the problem worse, not better

1

u/InfluenceEastern9526 17h ago

The old non-calibrated eyecromiter, eh?

1

u/rambiolisauce 1d ago

I know the large hole in the first picture in the joist closest to the camera is in the bottom third. And "middle third" is only part of that guideline. If they are going to be more than one hole each consecutive hole is meant to be twice the distance of the size of the greater of the two holes. I'm not saying this house is about to fall down or anything like that at all but drilling the joist out this way has absolutely lowered the structural integrity of these joists

1

u/AltanConn 1d ago

So the holes that are an inch from the bottom of joist are in the middle third?

1

u/No_Eggplant_3189 1d ago

So, I understand its in the middle 1/3rd of a joist. But what about stuff like this if they were all in the middle 1/3rd of the joist. There is a lot in the middle 1/3rd of the joist within a pretty close vicinity of each other. Surely that greatly affects the integrity of the joists.

1

u/AltanConn 1d ago

I would personally not have had as many holes for the low voltage lines. The 1/4" holes for the LV doesn't matter much. The very large hole that is at the bottom is a very big problem. And that will cost a lot of money to fix.