The dwelling pattern in Tehran in past decades was predominantly single-unit, single-family houses. The courtyard was an inseparable element of these buildings, and trees were considered part of the home's identity — so much so that even years after leaving these houses and moving into apartments, not only the types of courtyard trees but also who planted them remained in memory. The shared spaces of these houses — courtyards, wraparound terraces, attic dormers, rooftops, and basements — all had practical uses and enriched the dwelling experience for the household. With rising land prices and the inevitable increase in density, single-unit houses (of any size) were gradually demolished and replaced by four- or five-story apartments on pilotis.
In this housing model — a unit with one or several bedrooms, a few windows facing the courtyard, and a few facing the light well — the courtyard is effectively devoted to automobile access, the stairwell and roof have no spatial quality whatsoever, and the terrace dimensions are, at best, suitable for drying laundry.
The Nahal House project runs counter to the general current of construction in Tehran. It involves designing a single-unit house for a family of four (father, mother, and two children) on a 200-square-meter plot in the Pasdaran neighborhood of Tehran.
From the old house on the site, only a relatively tall cypress tree remains. The plot faces north, and the tree is situated right in the center of the southern edge, effectively hiding the building's facade behind it. Thus, the primary design goal is to create a dialogue between the building's body and the tree.
The building is conceived on four levels — basement, ground floor, first floor, and roof — and this hypothetical cubic volume has been divided into smaller cubes. Each cube has a separate function, but movement between them is fluid and smooth, and to bring natural light to the depth of the volume, some cubes have been removed (central void, northern patio, and sunken garden).
Due to the favorable prospect of the southern edge, the project's facade has been conceived as entirely transparent. To control the degree of view and light in the functions behind the facade, a unified skin has been devised, comprising closed, perforated, and open sections. This skin is essentially an intermediary space that reflects the influence of interior volumes, exterior vistas, and the existing courtyard tree. In reference to the symmetry of the old school facing the project, brick has been chosen as the material. The gap between the brick skin and the building volume is greened with continuous planter boxes.
To regulate environmental conditions, natural air circulation has been incorporated into the project. A radiator heating system is used for warmth, and an evaporative cooler is used for cooling — an appropriate choice given Tehran's dry climate.