setting out concrete

in this photo because our new floor was joined onto an existing  one i, used a level, levelled across
onto antoher wall and made a mark 300 mm above the stone as we wanted 9 inches of concrete
the rest would be brought up to finished floor level with screed. Also i was working to a time scale as all the prep work had to be done before 3 oclock as that is when the concrete was due.