Two ivy-clad rooftop penthouses in Hackney serve as prototypes for an off-site modular housing system transportable by standard lorry. Comprising two interlocked two-bedroom, two-storey homes atop an occupied apartment building, they feature floor-to-ceiling glazing and views toward the City and Canary Wharf. The modular units can be wrapped in adaptable skins with balconies and terraces, while the living ivy exterior evolves with the seasons, integrating the architecture into its surroundings.