Japi House by UNA Barbara e Valentim
Japi House sits in Jundiaí, SP, Brazil, a contemporary house by UNA Barbara e Valentim that turns to the foothills of Serra do Japi for cues. The project revives rammed earth alongside exposed concrete and a garden roof, tying durable craft to climate and daily life. Quiet from the street, it opens to sky and green inside.
About Japi House
Morning light skims a tawny wall, the texture coarse and cool to the touch. A low profile stretches across the radial plot, then yields to garden and sky.
This is a single-family house in Jundiaí by UNA Barbara e Valentim, organized around land, craft, and comfort. The core idea is built, literally, from the ground: rammed-earth walls set the tone, while exposed concrete and an accessible roof garden complete a pragmatic and expressive assembly.
Raise the Wall
A curving rammed-earth wall draws a firm line between street and interior life. Packed inside timber formwork, the compacted earth reads in horizontal strata that hold sun and shadow differently over the day. The sweep of that arc resolves the radial lot, turning geometry into privacy and orientation in one move. It feels elemental.
Concrete and Earth
Rammed earth carries warmth; concrete brings crisp structure and span. The two materials meet cleanly at openings and eaves, where the cooler tone of concrete sets off the mineral body of the wall. A vertical tower punctuates the low roofline, consolidating bathrooms, water storage, and technical systems—service contained, silhouette clarified. Tactility drives the composition, not surface decoration.
Courtyard and Verandas
Inside, a central entry splits a binuclear plan and leads to fluid rooms aimed toward the rear garden and pool. The internal courtyard pulls air through the household, pairing cross ventilation with steady daylight that reaches deep without glare. Generous verandas and eaves temper heat at the thresholds, so rooms stay bright yet protected (midday sun stays outside). Daily rituals drift between shade and open air.
Roof as Garden
Above, the accessible roof works as a planted terrace that thickens thermal mass and invites slower breezes. Soil and vegetation buffer temperature swings, easing loads while setting a ready bed for solar panels to harvest the broad horizon. The garden doubles as another living level, modest in expression but generous in use. From there, the land reads as continuous.
Plan, Plot, Horizon
Horizontality keeps the house grounded; the tower marks its services and fixes a point in the composition. The result is legible and calm, with rooms arranged to face green rather than street noise. Material choices do the heavy lifting: earth for mass, concrete for precision, planting for comfort and energy.
By late afternoon, the wall warms to gold and the verandas fall into soft shade. Air slips across the courtyard and the garden roof holds the day’s heat at bay. Craft, climate, and routine meet quietly here, each part doing its job without fuss.
Photography by Nelson Kon
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