The base stage takes about four weeks on a flat block (sample diary). The first days are the site cut and the trenches for the footings.
Then the steel goes in: bars in the footings and mesh across the slab, sitting on plastic chairs so the concrete can get underneath. The engineer walks it before anything is poured; that check is a hold point.
Pour day starts at 6:30 with the pump. By lunchtime the slab is level and the finishers are trowelling it smooth. It cures for a week before the frame goes up.