Spirals have often inspired architects. Spiral staircases take up less space than ordinary staircases. They are a helix shape, a curve in 3-dimensions that extends upwards or downwards but does not get wider. In the 1940s, Brynmawr Rubber Factory was designed with a helix staircase in the boiler house. It was a clever design that supported itself without a central column. It is similar to the double helix of DNA molecules.