Installed on the third floor of a Grade II* listed building, the Stone Stair consists of 13 intricately cut blocks of Italian travertine limestone, totalling nine tonnes, delicately stacked 10mm above the floor using an innovative, precambered shallow steel grillage. The size and weight of each block had to be carefully controlled to allow transportation via a hoist through the third floor window. Combining age old masonry techniques with modern day analysis methods, what at first appears as an impressive sculptural staircase reveals itself to be an impressive accomplishment of structural design.
This project presents an intellectual interplay of solidity and flexibility, facilitated through the skill of the structural engineer. The consideration of the erection sequence in combination with the painstaking, calculated prediction of forces led the judges to draw parallels with a three-dimensionally creative game of chess, in which the progressive move and countermove of load and deflection are skilfully played out in order to checkmate gravity.