In 1990, following a limited design competition, RRP was commissioned by Daiwa Europe Properties to design their new London headquarters on a site at the corner of Wood Street and London Wall. The twin economic recessions that hit Europe and the Far East, however, obliged Daiwa to rethink its strategy and the prestigious headquarters project was abandoned. The site stood vacant for three years, after which a new brief was given to RRP to design a speculative, high-quality, commercially lettable building, larger and more economical than its predecessor.
The site lies at the heart of the City of London, between St Paul's Cathedral and Moorgate. It previously housed two telephone exchange buildings, one of which had been spot-listed prior to the commencement of the works. The building was subsequently de-listed and demolished along with a 1960s office building. Within the existing basement, however, was a fully functioning British Telecom exchange chamber, which was required to remain in operation during demolition, construction and occupation of the new building.
Eighty-eight Wood Street is adjacent to the tower of the Grade I listed St Alban's Church, designed by Sir Christopher Wren (the remainder of the church was destroyed during World War II). In addition, the site is bounded by two historic churchyards; St Mary's to the south and St Olaves to the west (the latter destroyed in the Great Fire of London) . Surrounding the site are various contemporary buildings ranging in height from four to 23 storeys.
Planning permission was granted for the initial headquarters scheme in 1992. The development was the subject of protracted and complex planning negotiations with the Corporation of London planning department especially in relation to viewing corridors from the South Bank, St Paul's Cathedral and the Barbican terrace. In order to avoid resubmitting a new application, the development envelope established by the initial application was adhered to for the second design, despite the requirement for more floor space.
The conceptual design developed in response to the new commercial brief exploits the many planning constraints attached to the site to produce a building that addresses the demand of the office market. On Wood Street the scale is kept down to eight storeys to address the tower of St Alban's church. The true nature of the design, however, is revealed from London Wall, where it become apparent that the building is in fact comprised of three blocks, stepping up in height behind Wood Street first to 14 storeys, then to its full height of 18 storeys, with each block relating in height to its immediate context. The three blocks, each of 18 metre deep linked floor plates, and of varying length, are positioned parallel to Wood Street to acknowledge the historic street pattern, and the irregular shape of the site. The consequential number of setbacks has the additional benefit of allowing for a greater than usual number of corner offices, which are especially valuable in the London rental market, as well as unimpeded view out over the city. The stakced arrangement also allows the large 33,00 square metre building to be easily divided up into smaller, flexible tenancies as required.
In between the three blocks, then metre deep gaps are used for the 'servant' zones, such as stairs, lifts, and services. These are expressed as discrete architectural elements in order to maximise views and the space available for tenancies (the 'served' zones) within the main floor plates. The double-height entry and main reception area, accessed one metre above fround level to clear the telecom exchange below, cuts through the full length of the site from Wood Street to a secondary entrance from St Olave's churchyard gardens.
One element above all others characterises the design of Wood Street. Ultra-clear, low-iron glazing has been used for almost all of the building many facades. The glass has an extraordinary level of transparency compared to standard clear glass. Despite its surprising lack of presence, the glass acts as a robust protective covering for the whole building. Individual components such as lift shafts and staircases are able to be expressed to architectural advantage without compromising the ability of the facade to protect the interior and the inhabitants from the weather.
The stairs and the panoramic lifts are exposed to view, behind frameless glazing offering spectacular views as they travel up and down the exterior of the building. The lift lobbies on each floor end in full height, single panes of nearly invisible glass that has the effect of turning the lobbies into outdoor terraces with views overlooking the Barbican and the London skyline beyond.
Glass is also used to great effect on the office floors where three metre wide triple-glazed windows allow views across the capital on three sides stretching from St Paul's cathedral in the west to Canary Wharf in the east. In the eight metre high entrance space, again, the external walls appear to be virtually non-existent so that the space flows freely between the building and the surrounding streetscape.
The glazing system to the office floors also functions as a highly effective environmental control system. The building's main contribution to environmental efficiency lies in the use of internal blinds, integrated into the glazing system and controlled by photo-cells that automatically adjust the blind settings (fully closed, fully open or half open) and solar gain in hot weather, drawing it into the ceiling and expelling it.
The viability of the construction of a large office building on a severely constrained site depended on the resolution of a number of significant structural problems. The resulting structure is closely integrated into the architecture, which unusually for an office building, has columns set well inside the perimeter, and post-tensioned floors. The optimum structural grid of 15 by 6 metres is achieved by setting the columns 1.5 metres inside the perimeter, therefore minimising the number of low level transfer beams.
The superstructure diagonal bracing is a major architectural feature, appearing on the exterior of the short ends of the three blocks in bays of four storeys high. In contrast, the cores and stairs are stabilised by the building frame but due to the revealing nature of the glazing, again the structural detailing makes a significant contribution to the architecture. Details include pre-tensioned stair flights to stabilise the supporting columns and pre-tensioned rods acting as glazing mullions.
The first city building completed by RRP since Lloyd's of London in 1986, 88 Wood Street demonstrates the potential for speculative commercial development that does not compromise on quality and enhances the public domain.
The site, at the junction of Wood Street and London Wall, was formerly occupied by a 1920s telephone exchange. Delays in securing the demolition of this supposedly "historic" building, combined with the onset of the Nineties recession, led to the cancellation of a 1990 Rogers scheme for a prestige new headquarters for banking corporation Daiwa. A larger scheme was designed in 1993-94, with speculative letting in mind.
The 33,000 square meter building is arranged as three linked blocks of office accommodation that step up from eight storeys on Wood Street, where the context includes two listed buildings, to fourteen and finally eighteen storeys to the west, responding to the taller built topography towards London Wall. By using the extensive basement of the demolished telephone exchange for plant, roof levels were kept largely free. The office wings are constructed of in situ concrete which contrasts with the lightweight, steel-framed service towers containing toilets, lifts and dramatic, fully glazed stairs. The use of brilliant colour enhances their impact - air intakes and extracts at street level are also brightly coloured, contrasting with the neutrality of the occupied floors.
The generosity of the scheme is reflected in the spacious, 8 metre-high entrance lobby, floored in granite as an extension of the external landscaping. This reception area features a 54 metre-long wall running the length of the building. The facades of the main office floors are glazed from floor to ceiling to maximise daylight and views - in addition, levels 8, 12 and 16 lead directly onto roof terraces with spectacular views over the city skyline.
Though built to a strict commercial budget, 88 Wood Street contains many innovative elements. The massing of the building allows controlled daylight to penetrate the office floors. Its triple-glazed active facade is formed of single panels, each 3m x 4m, of highly transparent float glass. The inner faces of the external panes have a low emissivity coating which further reduces internal solar gain, while the cavity between the double glazed units and the third panel is fitted with motorised, integral horizontal blinds with perforated slats. Photocells on the roof monitor external light conditions and adjust the angle of the blinds, thus minimising sun-glare, heat gain and energy consumption.
City & Context
The site lies at the heart of the City of London, between St Paul's Cathedral and Moorgate and was subject to complex planning negotiations with the Corporation of London The building rises in three linked steps of 10, 14 and 18 storeys, responding to the geometries of the site: at its highest it complements the buildings lining London Wall, while the lowest block is sympathetic to the scale of the Wren tower in Wood Street.
The large floor plates allow for maximum flexibility, and can be subdivided into three separate tenancies, with each tenant still having direct access to lift lobbies, toilet facilities and all mechanical and electrical servicing.
The form of the building is in direct response to the need to protect the existing public realm, including the open spaces of the two churchyards (St Olaves and St Mary's) as well as a number of sensitive historic buildings adjacent to the site. The three block massing solution responds directly to the existing street pattern and the various heights of buildings in the immediate locality.
The sophisticated glazing system allows maximum daylight penetration to all floors, and incorporates integral internal blinds, remotely controlled to protect the building from unwanted solar gain and glare.
The double-height reception space cutting through the entire length of the site, the expressed vertical services and circulation towers are clearly comprised of 'servant' and 'served' space enabling clear access to all parts of the building.