WARNING! WARNING! Horrible puns ahead!
After a couple of years of having my 40X60 shop with only a dirt floor - I finally did it. Smooth. level. compacted sand, vapour (vapor to our US cousins!) barrier, 5 inch Hi density styrofoam, mesh plus rebar, and then lay in the PEX tubing for hydronic floor heat.
Then last Saturday, 5 and a half inches of 34 MPA concrete, with fibreglass strands mixed in, laid in, and machine finished and polished.
I was just "floored" by the amount of "concrete progress" and "mortarfied" that I hadn't done it sooner!
(I warned you!)