Opened in 1860, the Hampstead Junction Railway linked Camden with Willesden, relieving pressure from commuters and freight. Just east of Finchley & Frognal station, it sliced an open cutting across a sloping plot on Finchley Road. The line was capped over in the 1960s and a new building erected fronting the street. Over the following decade, the infamous Laker Airways operated a coach terminal here, ferrying passengers north to Luton Airport.

 

When Tindal Overseas acquired the site 25 years later, a dilapidated single storey office straddled the tunnel. They saw development potential but needed a scheme which safeguarded the trains and passengers speeding below and satisfied the planning policies of the neighbouring Conservation Area and Shopping and Service Centre.

 

Unlocking the site, an innovative structure with composite beam and slab in post tensioned concrete spans 17 metres over the railway. An elegant steel frame above creates a split roof, admitting diffuse northern daylight into the workspaces and suspending the intermediate slab from delicate hangers, avoiding columns over the tunnel. This yielded 1,400sqft of net floorspace designed to British Council for Offices standards and leased to blue chip tenant, Allied Irish Bank.

 

The extruded volume is wrapped in insulated render, recessive grey at the colonnaded lower level and crisp white above. Ribbon windows are shaded by metal brise-soleil and form projecting corner bays. Slotted in between 1960s slab and contemporary addition, a slanting steel and glass atrium with copper clad lift reconciles the levels and creates a dynamic entrance flooded with light.