Hi,
I have a question about floor joist. I had a contractor cut 2 inches out of the bottom of about 15 2x8 floor joist, to hide the electrical lines, instead of drilling holes through the middle of the joist. I would assume these would have to be sistered is that right or do have a major problem on my hands?

Thank You in advance.

You have 2 problems. You have a fool working in your house and you now have an illegal weakened joist. Did he pull a permit and will there be an inspection? I would demand that he fix the cut joist in an fashion that meets the expectations of the local building inspector and then do the job correctly. Notching a Joist | Framing | This Old House

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