The Sponge reimagines urban living in north London. Unagru delivered a free-flowing reinvention of this traditional north London terrace home. The Sponge project has reimagined a traditional Victorian terrace, delivering a bright and flexible family home. The name is inspired by the deliberate design intention of puncturing the house as much as possible with windows, skylights and glass, allowing natural daylight to penetrate deep within the building.

Project Name: The Sponge
Studio Name: Unagru
Project size: 240 m2
Site size: 880 m2
Completion date: 2020
Building levels: 4
Location: London, United Kingdom
Photography: Stale Eriksen

The Sponge by Unagru - Sheet1
View of living room ©Stale Eriksen

The scheme has extended the original dwelling into the basement, side, rear and roof of the property. This additional space has made it possible to rethink the historic circulation, preferring a more fluid layout to achieve an exciting experience of movement through the building.

The side and rear extensions are clad in dark stained marine plywood, with dark stained hardwood window and door frames. Below ground level, walls, paving, and stairs are all clad in stacked black bricks.

The basement and ground floor are interconnected open-plan spaces, designed to be directly related to the garden. Sliding doors, changes in levels and slatted screens have replaced partitions, doors and corridors to provide a fluid space with varying degrees of separation and privacy. Long convex joinery walls model the space at both levels, incorporating the services areas, storage and the kitchen units. A curling steel stair, encased in a slatted wooden box, gives access to the basement.

The Sponge by Unagru - Sheet2
Bedroom ©Stale Eriksen

The stair is enclosed into a loose wooden box that resembles an atrium, illuminated from above, and floating over a large fish tank installed in the basement. The stair and box are located in the middle of the ground floor, serving as both a direct connection between the two levels and light source in the layout’s darkest area. The wooden box acts as a perforated screen between the front sitting room and the open plan kitchen and dining area at the rear.

The circulation to the top floor covers multiple levels, with landings at every change of direction, the path extends on the ground floor and basement, through an exterior stair that connects to the garden and back into the ground floor.

The Sponge by Unagru - Sheet3
View of kitchen ©Stale Eriksen

The project’s original concept was creating the connection between the building to the sky through the three new volumes. The first, triple-height volume contains the entrance, stairs and landings on the top floors and is punctured by windows on both sides of the house. A second volume a literal box that encases the stair to the basement, composed of slatted wooden screens covered by a frosted glass roof. The rear extension also takes the form of a top-lit wooden box, attracting every possible ray of light inside, while remaining consistent with the project’s architectural language. Each of these areas functions as an internal greenhouse, enhancing the internal tranquillity of the home with natural greenery.

The home’s design inspiration has come from the clients’ interests and cultural heritage, resulting in an in-depth investigation of eastern and southern Asian architecture and its influence on contemporary architecture. The design needed a vital clarity of contrast between planes and volumes to achieve this particular feel to the interior. The interior plasters were tested, finally selecting off-the-shelf plaster to seal and leave exposed, in contrast to the dark stained oak floor finish and matching joinery.


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