[quickthrowman]

You can drill dozens of 10” holes through a concrete floor in a commercial office tower. The structural part of the floor are the tensioned cables inside the concrete, as long as you dont’t sever those, you can drill a ton of holes without impacting the structural integrity.

https://en.m.wikipedia.org/wiki/Prestressed_concrete

[grp000]

I used to work in concrete construction, doing post tensioned and SOMD for elevated slab. Coring might be simpler for SOMD, but post tensioned has such a high density of cables that I don't think it would work.

[loonster]

Commercial buildings tend to have very high ceilings. Maybe build a raised floor and put the plumbing under there.