A pair of twisted concrete fins frame a fireplace at the centre of this pavilion, designed by German architecture office NE-AR as an extension to an holiday home in Argentina (+ slideshow).

NE—AR was asked to renovate and extend a house on the banks of a lake in Río Negro, a region in south Argentina.

Designed to take advantage of its scenic location, the concrete addition sits apart from the existing house, providing a living space that opens out to the lake shore.

Its most prominent feature is the curving concrete column that houses the hearth and channels smoke up through the roof, while also providing structural support for the roof slab. This element gave the building its name, One Column House.

"One Column House researches upon the multiple performances a column could achieve beyond its structural capacity," said the design team.

"Firstly, it is an element that marks a central place by integrating in itself a fireplace, while articulating the program by organising the different functional spaces around it and orienting site-specific vistas."

The hollow column also features a space to store firewood, while pipes embedded within its curving walls help to funnel away rainwater – preventing it from dripping down into the fire.

The pavilion spans the gap between the boundary walls of two neighbouring properties.

A pair of long glass walls can slide back from either side of the space onto patios, while openings between the brickwork of the two end walls keep the interior ventilated in warm weather.

The patio facing the house is paved in red bricks laid in a zigzag formation. The one on the lake side is decked in lengths of timber.

"The existing house was lacking optimum spatial and functional distribution conditions that could fulfil the needs and the ways that the house was used and experienced," explained the architects.

"The house was sitting far away from the lake shore neglecting the most privileged views towards the lake and its landscape."

The space is furnished with a wooden dining set and stools that can be moved between the interior and decked patio for flexibility, while a concrete plinth integrated into one end of the structure is used as bench seating and for storage.

One end of the decked terrace cantilevers over the uneven ground and connects to the white brickwork of the original property, which contains two large bedrooms and a bathroom.

Tall wooden bar stools stand along the edge of a cast-concrete breakfast bar that separates the kitchen from the open-plan living area.

Photography is by Mike Mercau.

Project credits:

Design: NE—AR Nixdorff Etchegorry
Architecture research: Luis Etchegorry, Lars Nixdorff
Collaborator: Marina Rodriguez
Executive architect: Arch. Sebastián Costanzi.
Structural engineer: Ing. Martin Saiz; Urbana Saiquen
Construction: Sajoux Constructora
Visualisations: 3D Notos