Notches and holes in floor joist

Hey there folks

I thought I had a leak in my ceiling, the plaster was cracking a bit, so today I took a knife to it can cut out a section to take a peek.



Here is what I found - now there is nothing below this, it is my dining room. No support beam whatsoever and the nearest wall is probably 3', 4' and 6' away in either direction.

The beam has three holes drilled in it, and notch cut out of the top.

The beam is almost 6.75" long, and the notch is 2.75" deep.

Do I now have a structural problem and what can be done to correct this?

attached pics





Here is where it is

The notch in the top is a problem.

Is it a 2x8, or 4x8 beam?

Notches are never good. Holes in the middle, not so bad. A joist gets much of its strength from compressive strength on the top edge, and tensil strength on the bottom edge (sort of like an I-beam or truss that could be mostly hollow in the middle). Cutting it there significantly decreases it's overall strength. Cracks in the plaster show movement.

As far as repairing that notch, I would be tempted to pull the entire ceiling and making sure this isn't a typical practice of whoever may have worked on the home at one time.

I make a lot of holes in joists because I like to use metallic cable.

I try my best when placing holes.

Plumbers are the worst though when it comes to this.