Elliptical Staircase

Elliptical Staircase

This staircase is unusual because, in plan view, the inside stringer is curved in a half-ellipse shape. Meanwhile the outside stringer follows the rectangular lines of the stairwell walls. Note that no treads are square, but radiate outward to create a consistent tread width at any given distance from the handrail. This feature makes the stair comfortable to use.