Bois-le-Pêtre, Paris

The $15.4 million overhaul of Bois-le-Pêtre, completed in 2011, is a more explicit manifesto for renovation. Its roots are in a combined response by Lacaton & Vassal and Frédéric Druot to the French government's 2003 demolition plan: 'We were shocked by the idea that nothing could be done except tabula rasa redevelopment,' recalls Anne Lacaton. The two architecture firms embarked on a published research project which concluded that such buildings could be repaired and expanded for half the cost of replacement. Two years later, in 2006, the authors won a competition run by the government-funded social-housing provider Paris Habitat'OPH for the renovation of the tower and put their ideas into action.