This refurbishment and extension of a 1960s Modernist house in Primrose Hill was a unique opportunity: the house is one of only two detached properties in the Chalcot estate, and it is surrounded on three sides by communal landscaped gardens. The estate features a consistent material palette of white-painted brick courtyard houses and terraces. Our proposal removes unsympathetic alterations whilst creating open-plan living spaces internally. The key to this courtyard house is the relationship between the living spaces and the private rear garden. This is enhanced with a large picture window in the kitchen and full-height sliding timber doors in the living area. A rooftop extension creates a new space for yoga and meditation, with views over the Chalcots Estate’s landscaped gardens. This was the first upwards extension in the estate allowed under the new permitted development rules. Inspired by the trompe l’oeil in Azulejos tiles found in Portuguese manor houses, our design employs subtle shifts in material to create borders and frames in the new staircase, floor finishes and joinery details. High-performance insulation and an airtight layer have dramatically improved the house’s thermal performance. An MVHR system provides fresh filtered air with heat recovery, further reducing energy bills. An air-source heat pump meets all hot water and space heating requirements, creating a fossil fuel free home.