Tread coverings include a non-skid diamond pattern aluminum tread and solid wood. Galvanized steel spiral stairs are the second and more economical option.

Alex Chinneck's latest work sees the architectural artist reveal what he calls his most complex and ambitious sculpture to date: a spiral staircase that has a surreal twist and appears to be ...

Just above: a triple-decker with as many gables and decks and a towering spiral staircase standing in for a ladder. Rendered in pine board-and-batten, cedar tongue-and-groove, and bark cladding, with ...