We discovered, by comparing our basement with the blue prints, that the previous owners took out two teleposts and the 4X4 post that supports the stairs. We now know why the tiles on the floor above kept cracking! The beam of 4 2X10's has not been strengthened in any way, and there are two joins above where the telepost should be. We would welcome any input as I think this is a common problem.
Not much input we can reply with other than put them back.... Or were they not installed at all by the builder, which seems unlikely as there is a joist joint there. Hopefully, the concrete was thickened for the posts at correct locations.
Be safe, Gary
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