Kazuyo Sejima and Ryue Nishizawa: Design Principles of SANAA

How SANAA built a body of work on lightness, transparency and a deceptively simple plan.

Kazuyo Sejima and Ryue Nishizawa: Design Principles of SANAA

Kazuyo Sejima and Ryue Nishizawa, working together as SANAA, are among the most influential architects of their generation. Their buildings look effortless, almost weightless, yet they rest on a rigorous set of principles. This guide outlines the ideas that define their work and why it has shaped contemporary architecture so widely.

Lightness as a goal

The most immediate quality of a SANAA building is lightness. Thin columns, slender slabs and minimal structure make their buildings feel like they barely touch the ground. This is not a stylistic flourish; it is the result of careful engineering aimed at reducing the visual mass of structure until the architecture seems to dissolve.

Transparency and the blurred boundary

Glass is central to their language, but transparency for SANAA is about more than material. It is about softening the line between inside and outside, between one space and the next. Buildings like the Glass Pavilion at the Toledo Museum of Art use curved glass to make boundaries ambiguous, so movement and sightlines flow without hard interruption.

The plan as the primary idea

For SANAA, the plan often carries the central concept. The Rolex Learning Center in Lausanne is a single undulating floor with no internal walls, where topography organizes activity instead of rooms. Their plans tend to:

- Replace corridors with open, continuous space - Distribute program loosely rather than in rigid zones - Let circulation and use overlap rather than separate them

Radical simplicity

Simplicity in SANAA's work is hard-won. Reducing a building to a few elements, a roof, a column, a plane of glass, demands that each element be resolved completely. There is nowhere for a sloppy detail to hide. This pursuit of the essential connects them to a long Japanese tradition of restraint, and it places enormous value on precision of fabrication and assembly.

Ambiguity and freedom

A recurring aim is to give people freedom inside their buildings. By avoiding fixed paths and prescriptive rooms, SANAA creates spaces that users interpret for themselves. The architecture sets a gentle field of conditions rather than dictating behavior, which is why their public buildings often feel calm and open.

What practitioners can take from it

SANAA's lessons travel well beyond their aesthetic. The discipline of resolving every detail, the willingness to let the plan lead, and the respect for the user's freedom are principles any practice can adopt. Work that crosses design and fabrication, where a single misaligned reveal undoes the whole effect, understands intuitively why SANAA's restraint is so demanding. Their buildings prove that simplicity, done seriously, is among the most rigorous things architecture can attempt.