Hillingdon, the westernmost borough of Greater London, may be best known as the home of Heathrow Airport. But a stroke of design ingenuity on the part of London firm What_architecture has created a playful new landmark for the local community.
As part of its design for a structure connecting the Cowley Children’s Centre with the St. Laurence Primary School, this London-based, 12-person firm, which specializes in public design and community outreach, had the idea of using 1.2 million off-the-shelf Lego blocks to clad one side of the building, and involved school children in the design and the construction. The Lego wall runs across the entire façade fronting the inner courtyard of the newly christened Cowley St. Laurence Church of England Primary School and Children’s Centre and has earned the project a Guinness World Record for the largest on-site interlocking Lego build.
“The use of Lego was empowering in the sense that it allowed maximum public participation and facilitated the design process—as a building material implicit to child’s play that is both fun and educational,” says What_architecture director Anthony Hoete.
The 2,700-square-foot façade is affixed to 0.6-inch-thick fiber-cement board. Because the board expands and contracts at the same rate as the Lego bricks, this provides the wall with dimensional stability. As an added measure, the architects placed expansion joints along the Lego façade every 13 to 16 feet.
As it planned its design, What_architecture made a happy, useful discovery in the Lego catalog: bricks of various sizes with holes already in them. To ventilate the 2-inch cavity that separates the fiber-cement board from the plywood at the heart of the wall, eight-stud versions of these bricks compose 32 cruciform shapes, 4 inches square, spaced every 2 feet along the top of the façade. And two-stud versions were used to attach the Lego façade to the board: for every 11 square feet of bricks, approximately five screws, threaded through the blocks with holes and hidden behind solid blocks, hold the Lego wall fast.
Of course, Lego bricks are not a code-compliant building material, so to address the issues of safety and longevity, What_architecture brought 3M Netherlands on board to custom-manufacture a clear, spray-applied coating for fire, anti-fungal, and UV protection. The coating was applied to the exterior once the entire Lego façade was complete.
In all, the structure and its Lego façade took nearly two years to work their way through planning and building code regulations. Once the structure was complete, 38 volunteers and 420 students pieced the façade together in just under three months.
Ultimately, the concept of turning school children into designers and builders was a highly successful one. “It was a pretty bleak-looking school before we began,” recalls Hoete. “The idea that the learning environment can be fun definitely manifested itself with this project.”