As a result of the success of the RIBA Award-winning urban regeneration Promenade of Light in 2006, Tonkin Liu were subsequently appointed to continue the public realm redevelopment of Old Street Roundabout. Tonkin Liu's proposal: to close off the least-used northwestern arm of Old Street roundabout, converting it into a peninsula. Our proposal also rationalised the numerous subway entry points to Old Street station into one central, street-level entrance with new public realm above and below ground; vents, skylights and lighting were integrated into the proposed green landscape.

The principal architectural feature of the proposed station entrance, is a glass pavilion structure acting as a landmark beacon of light. Its proximity to the historic site of St. Agnes Well and the line of mature trees along Old Street to the west inspired the artistic concept of a tree rising out of a hole in the ground. Its triangulated tree structure, founded on biomimicry principles, maximised visibility, lightness, and sculptural quality. Stability against torsion and unbalanced loading of an off-centre trunk is ensured by means of steel tie rods and rib-less glazing solution. Structural sections are made with single circular hollow sections.

The proposed road layout reduces the frequency of collisions, particularly for cyclists and pedestrians. Lane layout and impact were studied through Pedestrian Modelling, Swept Path and Collision Analysis. LEGION modelling was employed to assess the most efficient design for pedestrians. Existing traffic signals on the roundabout, though effective at moving vehicular traffic, do not fairly address pedestrians, cyclists and the public realm. Two signalised junctions, with at-grade pedestrian crossings and a new kerb layout, were proposed. TRANSYT modelling concluded that queuing one the approaches would not be excessive, despite increased journey time.

More than 10 years after our proposal was submitted, Tonkin Liu was longlisted in an open call to redesign the roundabout with Old Street New Tree. The competition, run by Islington Council, called for ‘exciting, bold and iconic’ proposals for a new gateway structure or public artwork reflecting the area’s identity as a hub for digital innovation. Transport for London announced construction work to transform Old Street Roundabout is due commence in late 2018.

client transport for london, london borough of islington & london borough of hackney
location london, uk
status unbuilt, pending funding
structural engineer akt
transport planning jmp
m&e mecserve
quantity surveyor gleeds