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CollaboratorRICARD PAU





m2 Rehab.197

m2 Extension157

PhotographJOSÉ HEVIA

Mas Jec, Building Kin

Acknowledging and maintaining the value of self-built, fragile outdoor light structures that populate a magic yard built by ancestors. A triple house, one indoors, one outdoors, one where porches become the core that keeps past, present and future kin together.


Kinship of a lost rural time.

41°09’47.2″N 1°06’29.5″E.
A very big hidden plot at a five minute walk from the centre of Reus. In the middle of the site, a self-built country house. In the beginning, it was in the rural outskirts of town. Some worker’s retreat to spend weekends, summers, and grow vegetables. Since then, it has been surrounded by all sorts of suburban and urban constructions. It still keeps its quiet, peasant atmosphere. The presence of quite tall apartment blocks on the northern and north-western side protects the site from the strong Mestral winds, and shades it during the hot summer afternoons. Surrounded by this slight geological ring, a microclimate unfolds. We could take advantage of our neighbour’s accidental gift by using some lighter construction techniques and opening up towards the western sun. In here, the city erases more than it builds, and it shelters more than it civilises.

The JEC´s late parents bought this mas many years ago. They spent the second part of their life taking care of it. The father, using his skills as a watchmaker, patiently assembled additions, welding, screwing and growing all kinds of rooms, huts, shacks, sheds, porches, fig trees, clocks, strange plants, mono radios and shades: An outdoors abode, a second house around the former one-floor self-built construction. The house was in a perpetual state of construction, a never-ending laborious enjoyment for its dwellers. And then in 2016 the father died, and the place was empty.


From the House of youth to their last home.

A year after the father’s passing, the son, his wife and daughter -the JECs- decided to move back in. Their only initial wish was that they wanted to live on a ground floor. The site is big enough for a single-storey house, so they don’t have to go up and down the stairs when they get old. The existing mas had two floors, a flat roof -a terrat– on top, an underground cellar, and many shacks and porches, none complying with any code. The JECs first question was whether it was better to keep the mas, or to demolish it and build a brand new structure instead?

We carry the legacy of our ancestors in our minds and in our genes, and although it not possible to trace how each house they lived on has shaped those, this time it was at least possible to not erase completely J’s childhood landscape, the house and the garden he grew up in.

JEC is an acronym made with the three inhabitant’s names, but it also means winter coat in Catalan.


Presences and absences.

1. Building Materials.
As usual, the main building materials were for free -but not endless. Air, sunlight, breezes, weathers, neighbours, a garden planted by former selves, everything that is almost not there, everything that has just vanished. The place was so full of objects -watches, tools, radios, walking canes-, that we ended up taking away more things than adding, sharing our plans with the smell of ghosts. We painted the mas in the first color that the owner remembered from the first time he walked in the site.

Ground floor

First floor

Roof top

Late father's watchmaker workshop.

2. The bricoleur´s presence.
Through the years, on the weekends and holidays, the watchmaker invented a dense, humble, loose -and mostly illegal- atmosphere. Improvised porches and sheds where the family used to gather to cook, eat, and spend most of their time. The JEC’s recollection of these daily cheerful celebrations, and the fact that the first day we visited the site the house was exactly as it was the day the father died, transformed this dense absence into a material source. Memories became another important shelter to nurture.

Father's watchmaker workshop.

The father also fixed old watches for fun and hanged them all over the house.

Self-built porch.

Outdoors kitchen. The second house.

Outdoors kitchen. The second house.

Outdoors kitchen. The second house.

Self-built porch.

Self-built asbestos porch.

Self-built asbestos porch.



Porch roof.








3. Childhood memories.
J spent his childhood and adolescence in this house. He constantly went back with his wife and daughter to visit his parents. Their shared past experiences will be a part of their daily experience of the house we build now.


A self-built quality. The most fragile is the most valuable.

What made this place inhabitable? Its value was not the existing main house. Although its structure was in quite good shape, what made it inhabitable were its self-built garden structures. These outdoor shelters are the real quality of this place. They are impossible to design. Probably they are impossible to reproduce. They are extremely fragile, to the point that it seems impossible to repair them.

What we needed to find was a way to up-cycle these structures, and add some more inhabitable air among them. Our approach was not to touch what we wanted to keep -we would just brush it with paint.


Light reparations. Inside out? Differential analogies between inhabiting and weathers.

So neither we kept the old mas as is, nor we totally demolished it. Instead, we placed more antropic air in the worst area of the plot, which was often shaded by the main house. The extension is family to the existing porches. In order to minimise the impact of this new structure, we kept its weight light as a porch, using CLT panels and thin steel tubes.

Ground floor

First floor

Roof top

1. Two weathers.
The extension needed a conservative energy strategy, and within it, hyperlocal insulating solutions. Bedrooms were placed in its northeast side, so as to catch the low morning sun in winter, and were covered by ten centimetres of cork, to keep them warm at night. Along the new structure´s western side, the kitchen caught the late afternoon sun rays in winter, and we used CLT´s particular balance of insulation and thermal mass to keep a comfortable temperature and hygrometry inside.

The atmospheric strategy for the old mas is totally opposite. We didn’t introduce any new insulation, the original brick walls thermal mass was slightly altered by introducing small ventilations to help regulate its humidity and potential overheating in summer days. A big fireplace was placed as the central heating element in this now tall hall.


2. Activities.
By maintaining the old constructions, we got three autonomous habitats that the family will use according to their changing needs through the seasons and decades. We erased any trace of program or specific use inside the mas. Kitchen, gone. Bathrooms, gone. Rooms, gone. First floor, half gone. A space devoid of any programatical constraint, just an interior. Not useless, but with no particular predetermined use. What were once small dark rooms has now turnt, as if through some magic trick, into a tall light tower. What could be foreseen as a buffer space might become the daughter’s house. What was thought as a guest apartment might become the writing room…


Change of plans. Why build fast when you can improvise slowly?

We separated the bid in two: one for the off-site CLT panels system, with a tolerance of 2 mm; the other for the on-site wet and hot masonry work, with a precision of 2 days; and established a very simple protocol so the two parts could work well together. The engineered timber extension was assembled in two weeks by three carpenters: Gerard, Paco.

The old house took almost a year to be ready, and it ended up in a final paradox: we had to change many construction details to adapt them to the specific skills of the brick masons -Leo-, moving from BIM to bricolage, as if their hand’s were conduits of the late father’s soul, imprinted in the terrazzo made of reclaimed terrazzo pavement or in the polished brick floors.


Pol Masip. 26 July 2017.

José Hevia. 30 July 2018.


This is how the house was when the JECs moved in during summer of 2018:

Celebration. 15 July 2018.

The JECs invited their family and friends right after they moved in.

The family house, the place to go back to, is always under construction. A new life rises everyday at the mas JEC. We are grateful to them for that.

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As a consequence of our search as architects, we also produce understanding and knowledge made of words -written and spoken. This search revolves around twelve constant themes, questions we don’t have a definitive answer to yet. This knowledge is not just a by-product of our activity, but rather an instrumental part that develops simultaneously and is imbricated in building. Search Questions is our sisyphean effort to organize and share this knowledge while it's blossoming, fragile and unstable. By doing so, a more specific understanding, and more refined questions emerge.

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2. Endless beginnings

Graduation Ceremony. AAA. Aarhus, Denmark. September 2020.

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4. Open Process Ecosystems

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5. Subrural

An incipient theory of the subrural, first published in Catalan in AT magazine, edited by Nuria Casais and Ferran Grau.