An artist works on a painting on the unoccupied 48th floor of 7 World Trade Center tower overlooking the World Trade Center site in New York. Developer Larry Silverstein, who’s Silverstein Properties owns the tower which replaced the original 47-storey 7 World Trade Center that was destroyed in the September 11, 2001 attacks, has allowed a group of artists to work free of charge and paint the redevelopment of the site until the space is leased to a tenant.