The Arco House: where economy dictates concise design

Designed by the Chilean studio Pezo von Ellrichshausen, the Arco House was built in Concepción in 2011, in the zone worst hit by the 2010 earthquake. To fully understand this work, it must considered within the context of the difficult reconstruction process that has been underway for more than two years throughout the country, partly because the house its owners, two artists, lived in was totally destroyed by the earthquake but, more importantly, because it has the same common denominator as the other reconstruction projects, both public and private: economy.

In the Arco House, however, the concept of economy has injected meaning and condensed the principal design operations to convey the deep-rooted meaning of the work. Here, economy translates as structural honesty. The house comprises few architectural elements, a reinforced-concrete base, metal beams and pillars of the same size and extensive glazing. The form is a pure prism on four levels, the first of which is rooted in the ground while the other three counter the latter's inclination with their verticality.

These elementary choices have produced a geometric form that is simple to read. The house stand there, immobile, in a form that is torn between the vertical and horizontal lines of the design. The vertical line defies statics in an area at huge seismic risk; the horizontal line absorbs this tension and conveys a sense of great serenity. This unusual condition results in a balanced design in which geometry is key.

The economy of this design is not only linked to the use of few materials but also to the way the house was designed, as clearly visible in project drawings that present very few signs. Lacking in sophisticated detail, the work is resolved with elementary technology familiar to the unskilled Chilean labour force, meaning the house was built quickly and inexpensively.

Finally, in the Arco House, economy has meant, above all, making good use of the few available resources. The weight of the structure disappears in the house's internal spaces to make room for views of the landscape. This causes the small domestic spaces to expand outwards and the elimination of a visual limit between interior and exterior considerably enlarges otherwise quite small domestic spaces, virtually extending the area to infinity.

Light is another factor that plays a core role in this project. A blade of overhead light splits the prism in two, carving out the central nucleus containing the stairs. The luminosity increases as you climb from one floor to the next, transforming the staircase from a service space to the true heart of the house. This, by the way, is the only place where the vertical nature of the building is clearly perceptible. The staircase and fitted walls carve out the rooms and the few pieces of made-to-measure wooden furniture determine the programme and create the space.

Seen with this practice's other works, the Arco House shows some continuity with Pezo von Ellrichshausen's disciplinary research but, at the same time, this project presents elements that demonstrate the two architects' ability to evolve and put forward new themes in their designs.

Their best-known designs include the Poli and Fosc houses (presented at the 2010 Venice Biennale): virtually hermetic masses in which the tension between interior and exterior is entrusted to windows, strictly all square. The Arco House is, instead, totally explicit — inside and outside match. The first two designs were built in unfaced reinforced concrete and feature an absolutely stereotomic image whereas the research in the Arco House is tectonic and stresses the load-bearing structure of the building.

However, these houses do share the rigour of a design centred on intense respect for geometry and essence. Yet again, this architectural office has shown its amazing ability to synthesise and express itself in a work of modest size.