The Swiss Re building, better known as the Gherkin, has been the subject of recent alterations. The fit out of the 16th to 18th floors has involved D R Services constructing a bespoke staircase. The aim was to create a link between the floors which would not detract from views across the capital. This was achieved by making a series of treads and triangular landings in stainless steel with slots along the inside edge to receive glass balustrades . While 15mm toughened glass was used to take account of the potential loadings, the design solution made use of a dry clamping system enabling glass to be fitted as if into a concealed channel.