CPD Specifier May 2015 issue January 2014 | Page 9

Roofs As the National Theatre prepares to raise the curtain on its 50th anniversary season, Kemper System has ensured that its Grade II listed building continues to perform by providing the waterproofing membrane for a major refurbishment project. Famously described by Prince Charles as a ‘clever way of building a nuclear power station in the middle of London without anyone objecting’, the National Theatre is almost as famous for its architecture as it is for the quality of the productions it stages. Located on the South Bank of the Thames, it’s a pretty hard building to overlook, whatever your opinion of its modern concrete structure, and has been Grade II listed since 1994. For the team that manages the building, therefore, there is a significant responsibility to maintain the structure as a piece of national heritage, a public building and a busy workplace. Kemperol takes central stage at the National Theatre OPERATIONAL REQUIREMENTS One of the architectural features that make the National Theatre such an unconventional design are the distinctive terraced balconies that form its rectangular concrete silhouette. These provide both public walkways and roofs for offices below so when their original asphalt surfaces started failing, resulting in leaks, a solution needed to be found quickly. The re-waterproofing was carried out as part of the National Theatre’s £80 million refurbishment programme but one of the main specification criteria was finding a way to complete the works without an 䁉