Occupying the site of an iron age fort on St George’s Hill in Surrey, Camp End Manor is a Regency-inspired residence arranged around a central stone staircase.
Designed in collaboration with The Stonemasonry Company, the impressive staircase at the heart of the residence is formed of two flights of solid stone treads, leading from the basement up to the first floor. The flights are identical in geometry, set directly above one another, and supported only at each end while sweeping around a total of 265 degrees.
Both the 2.9m cantilever and the 265-degree angle of the elliptical stair were relatively unprecedented, so extensive analysis and testing was carried out to ensure the design was sound. First, a full finite element analysis model was made using three-dimensional solid elements to accurately model the stone treads and the mortar links between them.
The form of the stair was then adjusted with a deeper section on the inside to contain the cables and a thinner section on the outside to reduce weight and give a ‘lightness’ to the look of the stair when viewed from the landings around it.
Stone tests were carried out to determine the exact properties of the chosen stone in all principal directions, and a 70% scale model was produced to finesse the design and test the design. From this the analysis could be calibrated to closely predict the final stair, increasing the accuracy of calculations and allowing further design efficiencies to be made.
The result is an elegant focal point at the heart of this award-winning home.
- Design and Architecture Awards 2017Best Residential Property £20m+, winner, Sep 2017