The British Museum is visited by millions of tourists, students and academic researchers every year. To create more space for continuing expansion, and to allow for the modernisation of visitor facilities, the museum is witnessing change on a scale never before experienced on this tightly populated Bloomsbury site.
The museum's Georgian buildings were designed by Sir Robert Smirke in 1823. Original plans set four wings of galleries and libraries around a large rectangular courtyard. As work progressed it became evident that additional book storage was needed. This led to the construction of the famous circular Reading Room (1854-57) in the courtyard, adjoining the existing book-stack buildings, to house the British Library. Since then, almost all the open courtyard space has been filled with extensions. Smirke's stone-clad museum buildings forming the quadrangle and the iron-framed dome of the Reading Room are all Grade I listed.
Now that the British Library has moved to its new premises, the museum is redeveloping the Great Court, demolishing the bookstack structures, to leave the historic Reading Room as the centrepiece to what will be the largest covered courtyard in Europe. A spectacular glass and steel roof will enclose the 92m 73m courtyard to provide a central hub to the museum complex, including new galleries, education and visitor facilities, shops and restaurant. Underpinning the Reading Room will allow new basements to be excavated for a kitchen, plant rooms, seminar rooms and auditoriums.
Maintaining environmental conditions within the space involves ensuring that the public areas are comfortable, from the basement auditoriums to the restaurant on level six, which is directly under the glass roof. Essential to the environmental conditioning was the design and specification of the roof glazing, insulating the space and controlling solar gains. To provide for the different condition requirements, four new plant rooms will be constructed in the basements of existing quadrangle buildings, the services fed into the respective areas of the Great Court through a network of floor trenches.
The Reading Room will be restored, preserving the integrity of the domed structure and its unique papier-mache ceiling. The design and construction of the development makes use of specialist techniques to minimise the impact to both the historic buildings, and the continuous operation of the surrounding museum. The roof will be supported on 20 new composite steel and concrete columns around the Reading Room's perimeter, which carry the roof loads down to the foundations. To create the basements, the existing foundations of the Reading Room have been underpinned using jet-grouting techniques, which require small lightweight plant. During the work, both the internal environment and structural movement of the Reading Room will be carefully monitored to ensure that, if required, remedial action can be taken immediately to prevent any permanent damage.
Demolition of the bookstack buildings is nearing completion and preparations for the jet-grout underpinning of the Reading Room are under way. Installation of the steel roof structure is due to commence in the summer of 1999, with the project due for completion in the year 2000.
Stephen Brown, Andrew Chan, Neil Billett, Mike Cook, Peter Moseley, Peter Scott
Architect: Sir Norman Foster and Partners
Structural, building services, geotechnical and fire engineering, planning supervisors: Buro Happold