The extension was designed to complement the strong character of the existing building, so the external walls are constructed using reclaimed London Stock brick. The floor of the east-facing pavilion is also stock brick, which creates a continuous floor from the outside in. Glass, the other principle material, allows the brick detail to dominate and highlights the sweeping views across the river. The building’s relationship to the river and the existing chimneystacks dictated the roof extensions’ walls and windows. To maximize the views the walls are chamfered, with the bricks cut to the desired angle.The pavilion (pictured above) provided more freedom to experiment with materials as the client wants to retain the feeling of the roof being an external space to enjoy the river views. To achieve this, the external brick pavers are also used internally, creating a fluid and connected space. The walls are finished in a warm rustic polished plaster, which combine with the colour of the pavers to provide a soft contrast to the relatively hard exterior. The bricks were laid so that the stock number is visible, giving the room authentic character. The second, smaller sunroom adopts the minimal palette of materials used in the penthouse, to which it is attached. The deep, dark oak surfaces run through the stairs, rear wall and floor of the sunroom. This is again complemented by the warm tone of polished plaster walls.