Does unoriginal play a part in the creation of original?

Is creating something original simply as easy as combining two ideas together? Tom Sloan at Levitate Architects came up with a neat solution to a storage problem in this London Victorian apartment:

Story

The combination of a bookshelf and a staircase created this hybrid-sort of design, the library staircase. If you have a problem the design solution is usually found using inspiration from other existing ideas. As a designer I naturally take inspiration from things around me and apply my perspective to come up with a solution. Realising this may improve the way I approach problems and come up with answers. The challange to come up with a unique idea may be overcome in this way. By using unoriginal ideas to create something original.

(This also relates to what Roland Barthes was researching. The idea that original writing may never be achieved due to the material used being unoriginal.)