Check out this new spiral stair that flows elegantly from one level to another …

DNA 

Concept… The Strand

The single defining feature of the DNA stair is that it should look like a DNA strand. This look is achieved by the central staircase support and balustrade, which I have dubbed the ‘strand’. The domestic DNA strand consists of 3 main elements:

• A large diameter helical tube which supports the treads and inner balustrade.
• A small diameter helical tube that forms the inner handrail.
• Balusters which support the handrail and links the two helical tube

http://www.dnastair.co.uk/index.html