emmarchement

CONT: Just about any type of step arrangement can be designed with Allan Block. Stairs built parallel to the wall face ""follow"" the natural 1&1/2 inch setback of the wall. Stairs built perpendicular to the wall face will widen by 3 inches per step (to account for the setback on each side wall) as you go. Design these stairs with intermediate landings to keep stair widths consistent.
CONT: Endless stairs... Notice that the four sides of the stair walls that you may have perceived as a ""rectangle"" is actually not a rectangle. Opposite walls do not have the same length and adjacent walls are not orthogonal. This dimension was masterfully created by Escher to manipulate the stairs arrangement while at the same time seducing your vision to accept the perception of endlessness.