Titled “Take My Lighting But Don’t Steal My Thunder,” Chinneck’s bespoke work is set in the Covent Garden’s Piazza, one of the busiest tourist districts in London. The fantastical installation was built to create the illusion that a 40-foot-long section of the 184-year-old Convent Garden Market Building had broken free from its stone foundation and is floating unaided over 10 feet in the air. This magical weightless effect was achieved using over 500 hours of digital carving and 4.4-ton counterweights. A green market stall on the side of the building conceals a steel beam that is attached to the steel platform and the floating half of the sculpture.

To make the shell as light as possible, Chinneck and his team of over 100 contributors carved the sculpture out of a type of expanded polystyrene called filcor using 3-axis and 5-axis machinery. Scenery painters then covered the steel-and-filcor structure with materials such as Jesmonite, a gypsum-based coating that create the illusion of stonework without the added weight. Over a ton of paint was used to make the temporary installation look like the historic Market Building.

Related: Artist Alex Chinneck’s Mind-bending Building Facade Slides to the Ground

Nearly 15.5 tons of steel was used to build the structure, however, the heavy counterweights are strong enough to support the sculpture’s levitating upper half. “My objective was to create an accessible artwork that makes a harmonious but breath-taking contribution to its historic surroundings, leaving a lasting and positive impression upon the cultural landscape of Covent Garden and in the minds of its many visitors,” said Alex Chinneck. “The hovering building introduces contemporary art to traditional architecture, performing a magic trick of spectacular scale to present the everyday world in an extraordinary way.” The installation will be on view until October 24, 2014.

+ Alex Chinneck

Images via Edelman