6 inch deflection?
I used to install fuel ust’s. 2 inches would be a major issue.... Same with the guys installing shoring for the tank holes.
Egg up a fiberglass or frp-coated tank, your ass was in a sling. Liability was 10 million. You did it right or you didn’t do it at all.
a core made by an electrical contractor revealed a 9.5 inch slab.
This was the on the 2nd pan of a 3 story government building.
.. Explained a lot of trouble that the hvac guys where having with space.
And yes it got some folks scrambling.
BUT ... after some “calculations" and .. finger pointing ..behind closed doors .. it's was determined that the structure as built would be fine.( to much $$ to fix and the wrong people would take the hit)
That was 25 years ago and it's still standing ... so ..
The contractor had begun placing concrete in the center of the span ... no temp support from below. ... as the span deflected they just kept adding more to bring it to top elevation (laser). And it's wasn't just a few floor joists deflecting ....
I could tell you stories that would make your hair curl all day long.