Elizabeth Tower

The world-famous Elizabeth Tower is the pinnacle of the Palace of Westminster: the symbolic heartbeat and timepiece of the nation. Its triumphant restoration is a testament to the meticulous preservation of historic landmarks, craftmanship, and the integration of modern engineering techniques. At the project’s inception in 2015, the Tower and The Great Clock were overdue for its next repair cycle: the subsequent conservation and refurbishment project has been the most extensive in the clock tower’s 160-year history. Our objective was to undertake comprehensive repairs, whilst undoing harmful previous interventions, and extending its life cycle before the next refurbishment to 50 years, safeguarding its future as an indispensable cultural monument and heritage site. Works included comprehensive restoration to the clock’s face, mechanisms, and decorative elements; redecoration and re-gilding of the cast iron roof tiles; and extensive stone repairs. In addition, aesthetically displeasing asphalt waterproofing and a 1950s brick stair enclosure were removed, re-instating the open, original appearance and materiality with new Hopton Wood limestone flooring to match the originally intended finish. The brick stair enclosure was replaced with a new glass enclosure, protecting against driving rain and water ingress whilst retaining the view of Big Ben at the top of the spiral stair. This glass enclosure was extruded, allowing the addition of a platform lift into the Belfry from the level below, connecting with a passenger lift to the clock Mechanism Room and all intermediate floors. All existing mechanical and electrical systems were replaced, the works included the installation of new LED lighting to the clock dials and Belfry and the addition of humidity-controlled conservation heating, improving the energy efficiency of the historic clock tower fire safety systems. Purcell’s approach, using Building Information Modelling, marked UK Parliament’s first full employment of BIM Level 2. This was instrumental in the effective management of the external stonework package – which numbered around 1000 repairs - as well as the 3800 cast iron elements. The completed BIM model provides a rich and thorough heritage data tool. Specialist craftspeople from all over the country were involved in the project: by using traditional trades including stone masonry, gilding, glass cutting and horology, the project has invested in and preserved these heritage skills, in addition to preserving a pivotal built heritage asset. The completed project has seen the celebrated tower rejuvenated, restored, and brought into the 21st century with modernised facilities, ensuring it will continue to bring joy to its many visitors.