A glass staircase, set between the party wall and a glass wall, links the ground floor and first floor of the small three-storey terrace house and transmits light from a skylight in the roof.
Glass treads and risers are supported by pairs of 48 x 70mm stainless steel 'shoes' bolted at one side to a steel string concealed within the party wall and at the other side to the glass wall. With the outside edge dot-fritted for grip and visual safety, the treads are of 19mm clear toughened glass edge-bonded to a bottom layer of 15mm clear acrylic sheet.
The back edge of the glass and the front edge of the acrylic sheet are stopped short to provide a rebate into which the 12mm toughened glass riser fits. Silicone 'bubble tape' (3m vhb) was used to bond the treads to the shoes.
The glass wall - two sheets of 10mm toughened glass with an 8mm acrylic layer bonded between them - is made of three 3.5m-high panels siliconed together at the vertical joints. The wall rests on a channel set in the ground floor and at first-floor level is bolted to a 203 x 203mm uc-edge beam with stainless steel m20 pig-nosed bolts; it extends 900mm above first-floor level to form a glass balustrade.
Each glass panel was installed as a single 10mm glass sheet bonded to the acrylic layer. The staircase shoes were bolted to the glass with stainless- steel pig-nosed bolts; larger pre-drilled holes in the acrylic layer allow the bolt heads to fit flush with it. The third glass sheet was then adhesive- fixed on site and the panels were bolted to the edge beam. The acrylic sheet provides a fail-safe layer for vertical load and rigidity for lateral loading.