"The Garden" proposal by A4 Arquitectos for the Puerta Las Condes Competition

Read the original version in Spanish here.

A4 Arquitectos participated in the Puerta Las Condes competition, organized by real estate developer INDESA. The competition brief required developing a high-density, mixed-use program with extensive public space at the intersection of Apoquindo and Manquehue avenues (Santiago, Chile).

"The Garden" is sited within an urban form that is essentially a triangle intersected by a bar. Drawing from this origin, the project breaks down the bar and the triangle into two volumes of equal height—100 meters—a fundamental condition for the complex to act as a gateway. The two volumes are separated by 20 meters, creating the project's urban hinge—a space designed to both reinstate the site's commercial history and enhance the public-private realm, connecting it with public transit and establishing it as the heart of the complex.

"The Garden" proposal by A4 Arquitectos for the Puerta Las Condes Competition - Image 2 of 16 — Cortesía de INDESA

In regulatory terms, the building aligns with a plane parallel to the 10.50-meter mark, spanning four stories. This base restores the value of the towers, which yield all private front setback areas to public use. Rising above this prominent base, the towers feature a rhythmic height variation: every four floors of offices correspond to five floors of apartments. Double-height layouts are utilized in the residential units to match the overall heights of both volumes while enhancing spatial quality in both private interiors and common areas, which feature panoramic elevators and corridors with natural light.

The residential building is oriented to the north, ensuring that all units receive direct sunlight and offer a superior quality of life. This positioning, in turn, casts a shadow over the office building, reducing its energy consumption and enhancing the project's LEED performance. Additionally, the design maximizes facade exposure for both apartments and offices, prioritizing access to natural light.

Public pedestrian access is designed on two levels. Taking advantage of the site's natural topography—with an approximate two-meter drop between Manquehue Avenue and O'Connell Street—Level 1 is accessed from O'Connell. This entrance features a small lobby for the office building, connecting the basements, the street, and the main lobby on the fourth floor. The primary entrance is located on Manquehue Avenue at Level 2, which acts as the building's main facade since it is visible from afar when heading down Apoquindo Avenue from the east. This level includes an intermediate lobby for the residential building, mirroring the office entry, which connects the basement levels, the street, and the main fourth-floor lobby. All retail levels are linked by a large central void—a space enclosed within a translucent cube, rich in vegetation and natural wood elements that bring warmth and texture to the public space. This split-level entry strategy leverages pedestrian flow to boost the commercial potential of the different floors. Direct access to the subway is proposed at the landing of the existing escalators.

By aligning with the site's geometry—the bar, the triangle, and the uniform height—the design optimizes floorplate efficiency in terms of its area-to-perimeter-and-volume ratio. The structural grid for the housing is set at 6-meter modules, transitioning to a 12-meter span via diagonal structural elements in the fourth-floor lobby, thereby optimizing both the program spaces and underground parking layouts. The office building utilizes an 8-meter grid, which benefits the underground program layout and ensures a clean, unobstructed open-plan layout.

The residential building is split into two volumes, catering to two distinct user profiles: short-term and long-term residents. Three apartment typologies are distributed across these volumes:
Apartment 1: Maximizes natural light with a wider facade (1200 x 540 x 264 cm).
Apartment 2: Features a partitionable alcove for a sofa bed, providing an extra room for guests or Airbnb rentals (600 x 735 x 264 cm).
Apartment 3: Duplex = High spatial quality (600 x 600 x 528 cm).

The office building offers two floorplate configurations: an open-plan layout and a layout divided into three units. The open plan features a column-free interior, utilizing only perimeter columns and a central core to provide maximum spatial flexibility. The tripartite layout features office frontages ranging from 20 to 40 meters for an average area of 270 square meters, ensuring a highly efficient perimeter-to-area ratio that maximizes daylighting. Additionally, the project complies with shadow study regulations. The west facade—typically the most critical under these zoning guidelines—casts a shadow footprint smaller than the theoretical limit, thanks to the 20-meter central void created by the separation between the two volumes.