3 Christou Lada Street – Kaleidoscopic Pragmatism, Athens, Greece

ΛΑΔΑ 3, the name of the project, corresponds to its address, 3 Christou Lada Street, in the so-called "Business Triangle" of Athens, a dense labyrinth of narrow streets and alleys. Most buildings rise up to 10 stories high, and the narrow streets feel like canyons, obstructing views and severely limiting access to daylight.

Originally a three-story building from the 1930s, it was expanded in the 1950s and late 1970s and has been vacant since 2017. During the renovation, the architects focused on lasting quality and respect for local heritage. The goal was to create healthy, comfortable, and sustainable spaces by employing low-tech solutions that are easy to maintain and achieve the best possible impact in terms of energy savings and environmental quality.

For the nine upper floors of LADA 3, six floors are designated for open-plan offices. These are complemented by a green lobby with a café and lounge on the ground floor, a small auditorium, and meeting rooms on the mezzanine. The top floor features a multipurpose room with a generous terrace that offers an unobstructed view of the Acropolis. Auxiliary spaces, such as changing rooms, are located in the basement.

To achieve the highest level of comfort, radiant ceiling panels are installed in all office floors, creating a cooling effect in the summer through the circulation of chilled water. The conditioned air is supplied through displacement ventilation units that are discreetly integrated into the façade parapets, improving air quality and hygiene. This design eliminates the need for air ducts, shafts, and technical rooms which would reduce usable area and the floor to ceiling height.

With its elongated footprint and narrow facades, ensuring daylight penetration into the building posed a significant challenge. To guarantee that each office floor receives adequate natural light, the team developed a combination of three systems: The Kaleidoscope is a light shaft strategically placed at the centre of the building, featuring cladding made of prismatic mirrors and white diffusers. At its base, a pyramidal mirror is submerged in a water pool, designed to reflect sunlight back upwards, preventing it from being absorbed by the floor. A controlled water flow in the pool generates ripples, producing reflections and refractive caustics—rainbow-like, wavy light patterns—visible in the ground-floor spaces. An automated system alternates between calm and rippling water periods at fixed intervals, creating a dynamic visual effect and subtly marking the passage of time.

On the roof, a two-mirror heliostat system tracks the sun's path, continuously harvesting sunlight throughout the day and redirecting it into the Kaleidoscope shaft. The sunlight is then reflected downward, entering workspaces and public areas through specially designed openings in the cladding. To maximize the amount of reflected light and reduce its intensity, preventing glare, the team opted for a custom-built spherical convex mirror instead of a flat rectangular one. This secondary mirror, positioned directly above the Kaleidoscope shaft, was designed using parametric modelling and machine learning to achieve the optimal curvature. Inspired by NASA's James Webb Space Telescope, the mirror was constructed from seven hexagonal segments, each of them individually shaped and curved that combined result in the overall mirror shape.

The third element of daylight provision consists of redirecting light at the south facade using light shelves. These fixed horizontal devices divide the window surfaces into approximately one-third at the top and two-thirds at the bottom and can be found both outside and inside the building.
The outer part functions as a fixed horizontal sunshade, protecting the lower part of the window from direct sunlight and glare, particularly against the intense solar radiation in summer. This allows for an unobstructed view to the outside.
The inner topside of each light shelf is coated with a highly reflective mirror surface that redirects sunlight entering the upper part of the window towards the ceiling. The bright ceiling diffuses this light, increasing brightness inside the space. This allows natural daylight to penetrate deep into the room without glare, reducing the need for artificial lighting.