The building, designed by Nimmo & Partners to replace the 1930s Associated British Pictures Corporations headquarters, which previously stood on the site, has been expanded by John Robertson Architects to offer 2,739m2 of office space over eight floors. The increase in floorspace was enabled by removing rooftop plant screen to create an additional office level and partially infilling the rear courtyard.The refurbishment respects the character of the surrounding heritage area. New mansard roofs on the upper floors echo the style of neighbouring buildings. The main entrance has been redesigned with changes to the faade at the corner of Golden Square and the ground floor now includes a larger reception area and a flexible retail unit. Source:Edmund SumnerTerraces have been added on several floors, including a communal rooftop terrace with seating and planters, creating a verdant space in a dense urban area. The buildings exterior uses neutral materials to blend in with the historic surroundings: Portland stone, dark-grey aluminium panels and zinc cladding. Public art from the original faade has been retained, depicting the sites history from becoming the home of distinguished 19th-century surgeon John Hunter to its more recent connections with the film industry.Advertisement Source:Peter CookArchitects view30 Golden Square highlights JRAs retro-first approach. The key design move has been the re-imagining of the building services strategy to create both an additional floor of accommodation and a communal roof terrace with fantastic views over Golden Square and Soho. The design and materiality tie the building back into the fabric and history of the site and has been well received by tenants looking for best-in-class facilities.Festus Moffat, director, John Robertson Architects Source:JRAStreet elevationProject dataGross floor area 4417m2Form of contract Design and BuildConstruction cost 14.2 millionConstruction cost per m2 3,215Architect John Robertson ArchitectsClient Aviva InvestorsProject manager AlbanPlanners Gerald EvePrincipal designer Lesley ClarkCommunity consultants ConcillioStructural engineer Taylor Whalley SpyraCost consultant MadlinsHeritage consultant Kevin Murphy HeritageSustainability consultant CundallBuilding control officer SocotecLighting consultant GIA EquationM&E consultant and sustainability consultant CundallFire engineering Consultant Trenton FireFaade consultant Thornton TomasettiAcoustic consultant CundallMain contractor StructuretoneEnvironmental performance dataAirtightness at 50Pa 9.49 m3/h.m2DHW heating demand 14,534 kWh/yrTotal regulated emissions (Part L 2013 Baseline (TER)) 98 tonnes CO2/yrTotal regulated emissions (Be Lean) 77.2 tonnes CO2/yrTotal energy demand 336.9 MWh/yr