THE RIGHT MIX
By Richard MacCormac
This essay first appeared in the Architects’ Journal 9 July 1980
It is increasingly obvious that, in the immediate future at least, most major urban development initiatives will have to.come from. the private sector. The problem will be, as it was during the last excesses of private enterprise in this field, to reconcile the rapaciousness of the developer with the needs of the community. Below, Richard MacCormac describes a study* his practice, MacCormac and Jamieson, has undertaken of the Spitalfields area of east London. Here, based on an analysis of part of Venice, undertaken with Ove Arup & Partners, he has produced a scheme which demonstrates how a modern development with a high plot ratio and large proportion of office space can conform with the scale and duplicate the rich mix of uses that characterises the area. It proposes that mixed use and glazed atria offer overall energy savings and speculates that atria and malls encourage a conviviality of public life.
(* The study was presented in April 1980 at the Centro Culturale (Tre Occi) in Venice Radiotelevisione Italiana)
Spitalfields is a decayed area of mainly eighteenth and nineteenth century development dominated by Nicholas Hawksmoor’s Christ Church (1725) currently being restored and used for the performance of Baroque music. The market site, which forms the subject of this study and which has an uncertain future, is a short walk from Liver pool Street Station and is connected to Bishopsgate by Artillery Lane, a shopping street of interest and quality.
The area is characterised by a lively multiplicity of uses; housing, offices, shops, workshops, restaurants, pubs and the streets are used for markets.
Buildings are generally four or fivestoreys high defining streets of various widths.
A conventional developer would wish to maximise the area of office space on the site up to the permitted plot ratio of about 3 5:1. A conventional approach would be to stand a tower on a podium. To achieve the plot ratio the tower would be 15 to 20 storeys high with a base of two to three storeys. Such a monolithic scheme would be out of scale with the surrounding area, would affect the local climate with downdraughts and turbulence, and would contribute nothing to the street system, either in form or content. It would deny the multiplicity of activities which are characteristic of areas like Spitalfields and deprive its own users of any sense of participation in their surroundings.
Venice as a comparison
Venice is an exemplary European city not only because of its canals and the quality of its facades, but because it offers a system of public, semi-public and private . spaces in which a multitude of public and private activities are inter related and reconciled.
Our study of a typical area of the city revealed a high plot ratio (3.5:1) but the buildings generally have a street scale. The public experience of the city was not of buildings as solid objects, but of the spaces enclosed by the surfaces of the buildings. These spaces were found to be arranged in sequences of public, semi-public and private enclosures, in which deliveries and refuse collection mingle unobtrusively with pedestrians.
An analysis of uses showed offices, shops, workshops, housing and services such as banks, co-existing in various combinations of plan and section. Large public buildings such as churches, and theatres, in which the activities do not relate to the street, were sometimes buried in the fabric of other uses and announced themselves in the street façade emblematically with pediment or portico.
The public spaces of Venice were seen to be each a forum of public life in which people meet.
There were also in Venice a number of semi-public spaces in the form of glazed atria which were the courts of former palaces. These included the post office building, the Coin Supermarket, the Grassi Art Gallery and the sumptuous interior of Danieli Hotel. Each is an extension of the environment of the building around it. Space may be ambiguously external and only partially heated, as in the post office, or ambiguously internal and completely heated as in the Danieli. Daylighting varies from the brightness of the post office court and the Grassi to the dim Gothic opulence of the Danieli.
In terms of building form, our proposal is an inversion of the conventional developer’s planning stereotype of the ‘50s and ‘60s. Instead of a tall building set back from the boundaries of the site or on a low podium our proposal goes up to the existing street lines and invites spaces and entrances to be carved out of it in response to the surrounding street pattern. Although the plot ratio is 3 5:1 the scale is only five storeys like adjoining streets. It offers a series of glazed courts and malls adaptable to many public and semi-public functions.
To test its urban qualities we have subjected our Spitalfields study to the same series of analyses used for Venice.
The block diagram of the ground floor illustrates how the overall form is fragmented. The routes between the blocks render the whole site accessible and link the scheme to existing roads.
The spaces in the buildings are of three kinds, public, semi-public and private. Private subdivisible space is within the blocks; the principal public space is the longitudinal mall developed as a covered route between the corner of Brushfield Street and the proposed arena beside Commercial Street. The glazed courts on each side of the mall are precincts, comparable with the spaces contained within the city blocks of Venice. They are interpretable either as tributaries of the public thoroughfare or as semi-public spaces for particular uses such as foyers, exhibitions and so forth. They are the ‘light wells’ of the scheme and as such are equivalent to the windy residual areas out side conventional developments which enable them to conform with light angles. Here they increase the ground floor of the building by about 20 per cent while the cost of the fabric enclosing them remains largely attributable to the surrounding office space. Servicing by vehicle is envisaged at a semi- basement level so that deliveries can be brought close to shops and workshops and double handling is limited.
The GLC survey of 1972 shows Spitalfields as a mosaic of different uses, residential, offices, shops, workshops. Our proposal continues this pattern of multi-use through-out the ground floor, fronting the malls with shops, workshops and studios. The semi- public courts offer such uses as a hotel foyer, supermarket, banking hall, post office, library, exhibition space, restaurant, wine bars, and theatre. Each court is a forum or arena around which are office spaces like galleries.
The inhabitants of the upper levels become spectators and participants in the activity which the building contains, as in traditional squares or piazzas.
Architects have tended to classify visually and spatially and to be more interested in buildings as containers than in the animation of the spaces they contain. Now there is a move away from the cool abstraction of the modern movement towards the idea of building as a framework for the experience of activity as exemplified by Hertzberger’s Centraal Beheer.
The scheme is like an artificial hill, its south side and top layered with housing to take advantage of passive solar gain. Where it faces onto Brushfield Street, the housing is a rough brick crust through which the smooth ceramic-faced construction of the commercial accommodation is glimpsed. The housing articulates the entrances to the courts and mall and to the theatre buried within the scheme.
To the west we have suggested how the development might relate to an adjoining site. To the east the offices are protected from the noise and fumes of Commercial Street by a series of glazed arboreta and to the north there is the suggestion that the elevation might break down in the centre and avoid over shadowing Lamb Street to offer a formal cue to future development to the north.
The scheme minimises energy consumption through the following design strategies which were devised in conjunction with Ove Arup and Partners.
– A compact form with minimum external periphery.
– The use of ‘free’ ambient energy sources. Predominantly south-facing housing acts as an external crust to the scheme and takes maximum advantage of winter passive solar gains. Energy consumption by the offices is minimised by admitting natural light through glazed courtyards and gallerias.
– The use of buffer environmental zones between the external climate and the internal controlled areas. Environmental conditions within the glazed courtyards vary with external conditions and are only controlled when sedentary activities take place.
– Energy transport between different uses. Certain users have energy spill particularly at inter-seasonal periods. We have hypothesised a mix of uses when the excess energy spill from offices, restaurants and shops can be utilised to heat the dwellings. The scheme offers planning gain for the public while satisfying development criteria. Its potential lies in the inter-relationship of different uses to offer energy economy and the high plot ratio of office development with a traditional urban form could provide for a low rent mixed uses on the ground floor.