“The disposition of the space between buildings and its detailed treatment are of vital importance. The way this open space is handled can either echo or deny the particular design intention which, in some places, may be to link groups of buildings and spaces enclosed by them or, elsewhere, to give expression to their separate and distinctive character. The raising of some of the terrace blocks on columns – allowing space to flow, as it were, beneath these buildings – is a device employed to express continuity between different parts of the layout and to avoid what might otherwise be, in a high density scheme of development, blunt and oppressive enclosure by buildings forbidding in scale.”

Chamberlin, Powell & Bon, Architects “Barbican Redevelopment” April 1959

The Barbican estate project aimed at high density of residents – 570 persons per hectare. But that had to be matched by a required amount of open space. As a condition of planning permission for an estate with a population density of 570 persons per hectare, the London County Council required that the Barbican scheme had to include “the provision of amenity open space to a standard of 1.5 acres [0.6 hectares] per 1,000 population” and “a system of elevated pedestian walkways integrated with that proposed for the non-residential part of the Barbican area (London Wall)”.

The planning rules required the City Corporation to provide 3.9 hectares [9.6 acres] of amenity open space to achieve the minimum level of 0.6 hectares [1.5 acres] per 1000 population. In fact, Chamberlin Powell & Bon and the City Corporation achieved 9.5 hectares [23.5 acres] of open space in the 15.2 hectares [37.5 acres] site of the Barbican estate, which is much more generous than the minimum requirement of 3.9 hectares actually required in the town planning approval.

Much of the saved space was achieved by clever design of towers and terraces, as explained by Chamberlin Powell and Bon.

“It is only possible to combine spaciousness with high-density development by concentration. If the large number of flats required are built in such a way that they cover only a small portion of the total site area, the rest of the ground is left free to be laid out as desired.”

An important idea in Chamberlin Powell and Bon’s plan was that almost every part of the estate could be ‘walked on’. One of the way this was achieved was to have many of the terraces of the South Barbican raised on columns so that people can walk beneath them and see beyond them. Chamberlin Powell and Bon explained their aim:

“Moreover, the use of land lost a building at ground level is, in a sense, regained in the form of terraces and roof gardens which crowned most of the buildings. The layout plan which shows all the roofs illustrates this approach to the creation of a garden city, which is, at the same time, truly open.”

The use of pillars to raise many of the buildings above ground level and to allow pedestrians to walk beneath, was a deliberate attempt to create a sense of flow and continuity between the spaces enclosed by the buildings.

These pillars are very satisfyingly thick and solid. They remind me of the pillars you find in Norman cathedrals, like Durham Cathedral, as opposed to the more elegant Greek-style columns of buildings in Kensington and Chelsea. There is something very pleasing about Norman columns.

The handling of open space was well executed. Chamberlin, Powell & Bon created the two gardens and the lake between them, all of which are sunk below ground level. As they described it:

“The principal open spaces enclosed by the long terraces of building south of Barbican are laid out on a large scale with grass, forest trees and water gardening, as is familiar in the London parks and squares.”

The tiled surface of the north podium (between Ben Jonson House and the back of Shakespeare Tower) flows round small gardens which break up the potential monotony.

“Formal gardening is restricted to the podium and the small, sunken, enclosed courts, where the pattern of planting can be appreciated by pedestrians moving about on a higher level.”

These effects were carefully thought out. As Chamberlin Powell & Bon proposed in their 1959 Report:

“The continuity of paved terraces extending under buildings and the areas of planting or water which link and define the open spaces make a significant contribution to the unity of the whole; the careful detailing of the hard and soft surfaces of the open spaces will add point to their form and contribute greatly to the delight of the scheme for those who are to live there.”