Poured and screeded directly over the pressure-tested tubing.
Pour day
Poured around the tubing, not over a guess
Once every loop is tested and holding pressure, we pour and screed the slab around it, keeping the tubing at the right depth so heat transfers evenly through the finished floor.
Reinforcement mesh goes in where the design calls for it, and control joints are planned around the tubing layout so cutting later never risks hitting a line.