“The long terrace blocks are grouped in meandering ‘U’ and ‘Z’ shapes on plan each enclosing, or otherwise defining, certain parts of the layout. … The areas of the site partially enclosed by these long terraces are comparable in scale to some of the familiar London squares.”
Chamberlin, Powell & Bon, Architects “Barbican Redevelopment” April 1959
The positioning of terrace blocks at right-angles to each other, was a deliberate imitation of residential squares in Chelsea, Kensington and Bloomsbury (whose inhabitants might be rather surprised by the comparison).
The most obvious example of a “U” configuration is the group of John Trundle, Bunyan and Bryer Courts which together form three sides of a square and enclose a lovely secluded garden in the centre with its own little fountain, as well as the tiny lake in front of Bryer Court. Someone put an awful lot of design thought into the details of this miniature gem.
Defoe House, Lambert Jones Mews, Thomas More House and the west wing of the Girls’ School form a complete rectangle round Thomas More Garden, which conforms even more to the spirit of the Victorian square by having the central garden as a private preserve of the residents.
Beyond the Barbican Arts Centre, Speed House, Brandon Mews, Andrewes House and Gilbert House form a looser enclosure, but still with Speed Garden and the lakeside reserved for residents only.
The two examples of a “Z” formation are the combination of Seddon House, Thomas More House and Mountjoy House, which are physically joined, and the group of Wallside and Postern (also physically joined) positioned next to Andrewes House.
Ben Jonson House and Breton House are exceptions. But even they are joined together as a “T” to form enclosures on each side similar in effect to the rest of the terrace layout.
The same idea affected the layout round St GIles’ Church. The architects said: “The City of London School for Girls and the row of terraced houses south of the remains of the Roman wall [Wallside] are linked by the podia in such a way as to enclose a small square round St Giles’ Church”.
Of course, the danger was that, by enclosing space to prevent the Barbican resembling the Mongolian steppes, they would make the enclosures forbidding or claustrophobic. Chamberlin Powell & Bon were alive to that problem and their answer to it is dealt with in “Space”.