Reinvesting inherited capital.

We must continue to use, rework and cherish the buildings we inherit, for collectively they represent humankind's greatest investment in energy and materials.

Richard Rogers' report on urban regeneration (AR August 1999) is packed with proposals for bringing people back to cities, chief among them 'a new vision ... founded on the principles of design excellence, social well-being and environmental responsibility'. It predicts that, with improvements, the present trend of depopulation of English cities could be reversed in the next 20 years.

Creation and restoration of the dynamism of the city, of which places like Barcelona and Amsterdam are successful examples, can be achieved by urban design. This is the philosophy adopted by the Urban Projects Group at Buro Happold. It is a multidisciplinary urban design consultancy, promoting an integrated approach in addressing complex urban problems where an overall understanding of strategic, design and technical issues is required. The test of good urban design, the group believes, is to create successful relationships which in turn will create successful places attractive to the user and the investor.

Regeneration is also concerned with restoration of the existing urban fabric and new insertions into original urban contexts which are sympathetic to their environment. The Roman Baths Museum and Pump Room in Bath, England, a unique tourist attraction, were refurbished with Feilden Clegg in 1988 with a new entrance reception, lavatories and kitchens, while Roman remains were restored and re-lit While work was in progress the structure was repaired and strengthened.

A more rigorous structural transformation has been made to a nineteenth-century former heavy engineering workshop on Cardiff dockside (with Ahrends Burton & Koralek). The original wrought iron frame was enclosed with glazed walls and a light arched roof to provide a science and technology centre, known as Techniquest. The Planar-glazed walls are supported on light steel trusses which in turn carry steel mesh sun shades. The vertical trusses resist wind pressure and the horizontal trusses resist wind suction, allowing very delicate steel members to be used and minimizing internal service requirements.

A new insertion into the city fabric, the Wilmersdorf pumping station in Berlin lies next to the early nineteenth-century original. The main structure, a deep concrete caisson, is topped with a delicate glass enclosure.

Now under construction, the refurbishment of the Great Court at the British Museum is a scheme won in competition by Norman Foster and Partners. Robert Smirke's original museum galleries were designed around the Great Court; the famous round Reading Room by Robert's brother Sydney was constructed at its centre in 1854 and the rest of the court was later filled with extensions.

These have been cleared away, leaving the Reading Room as the centrepiece of the original courtyard which is being covered with a triangulated glass and steel roof in toroidal form. The light roof delivers only vertical loads to buildings around the court, while 20 new composite steel and concrete columns support it at the perimeter of the original delicate cast iron structure of the Reading Room, The courtyard will contain new visitor facilities and new galleries at lower levels.

Shakespeare's theatre, The Globe, has been rebuilt on Bankside in London, close to its original location. It is a reconstruction of the original building, as far as it was known from sketches of the period. The oak frames were constructed using traditional jointing and setting out techniques. They support a simple double-pitch roof on purlins with a thatched covering-the first to be allowed in London since the Great Fire of 1666.

In the last three years Buro Happold has participated in the design of over 17 arts and theatre projects, many of them refurbishments of original buildings. In Scotland, Tramway, a successful venue for the performing arts on the south side of Glasgow, is a former tram maintenance depot built in the 1 880s, which is being extensively refurbished with Zoo Architects, The two auditoria, the gallery and the bars will be refurbished, with improvements in public access and circulation. A low-energy natural ventilation strategy will be adopted throughout the building.