Steps fail at the top riser before anywhere else. A flight is a heavy block standing on a small footprint, and where the ground under it gives, it settles as a piece and tips back from the door it serves. The gap opens first at the threshold, then the top tread pitches toward the house and holds water against the sill. Pin the flight to the stoop and stand it on compacted base, and it moves with the house rather than away from it, for as long as the house stands.
Rio Hondo El Monte Concrete was started in 2015 by Ismael Duarte, after 21 years on the San Gabriel Valley concrete crews, and he sets the riser heights himself on every flight. The houses on the tracts here were built with two or three risers up to a raised floor, poured by the tract crew with no steel and no tie to the stoop, and sixty years later most of those flights have parted from the house by an inch or two. That gap is the job we are called about most.
Flights are built to the California Residential Code under a CSLB C-8 concrete license, with liability insurance on every job. Risers are held to no more than 7 and 3/4 inches and treads to no less than 10, with no step differing from its neighbor by more than 3/8 of an inch, because a tread even half an inch off catches a foot in the dark. Four risers or more take a rail. Every flight leaves with a written workmanship guarantee against defects in how it was built.