Study: Daylight in UNStudio Architecture

In general, daylight is the primary source of light in buildings. With a holistic and custom-made approach, UNStudio aspires to improve the quality of daylight in its buildings as well as their users’ well-being. Six UNStudio projects highlight our achievements towards this end.

Buildings with optimal daylight design attain high energy performance not only by receiving as much daylight as possible but also by controlling the brightness of surfaces within users’ fields of vision. Such designs generally encourage daylight to penetrate a building but in some cases the goal is to reduce its degree or intensity.

UNStudio sees sustainable design as an integral aspect of contemporary architecture. Sustainable solutions such as daylight systems are not treated as add-ons, but related to each and every building element.


In the last few years, UNStudio’s Sustainability Platform has been developing several daylight studies across a variety of projects. These developments are expressed in three main features: design strategies, architectural elements and tools and devices. Depending on location and building typology, the parameters of direct and diffuse radiation and sun impact studies lead to conclusions that have influence on orientation, massing, programme and envelope.

After a process of digital and physical prototyping, the digital analysis of the building geometry and the amount of facade openings help to find a tailor-made solution for each building complex and environment. Finally, all these considerations are integrated into a holistic solution which aims to decrease the total number of components and, consequently, the maintenance costs. The following projects materialise UNStudio’s ethos of future-proofing the future, specifically with regard to daylight and sustainability.

UNStudio Tower, Amsterdam, The Netherlands

The 21-storey UNStudio Tower forms part of the Mahler 4 urban complex, a cluster of six buildings located in the heart of the South Axis in Amsterdam, each one carrying the name of its designing firm. In general, the sustainable solutions included four features: materials, climate, thermal glazing and energy saving installations. Regarding daylight, two main concepts shape the building. First, the central voids form a vertical accent and connect the inside-outside. This inside-outside relationship extends the facade envelope and turns the surface of the tower into an active medium with a profound effect on the quality of the interior user space.

Custom coloured glass panes are incorporated into the vertical voids, offering different identities and light qualities to the communal spaces which surround each void in the interior. These voids further facilitate daylight penetration deep into the voluminous 40 metre by 40 metre floor plates.


Increased window surfaces in offices

Secondly, the horizontal articulation is provided by white, aluminium bands which wrap the tower, whilst their varying size, depth and transparency ensure the correct balance of sun screening and light penetration to the interiors on all levels of the building. Additionally, the thermal glazing of the glass panes allows for sufficient daylight penetration, whilst reducing direct sunlight.

Daylight redirection device

Voids aid with light penetration, function identification and ventilation

2. Education Executive Agency & Tax Offices, Groningen, The Netherlands

This project accommodates 2,500 employees of the Dutch government in the Education Executive Agency and Tax Offices. It reflects and caters for the separate identities of both user groups, whilst simultaneously creating synergy by means of shared use of secondary spaces, among them underground parking facilities, public gardens, a central hall and a pavilion for commercial functions.

The inclusion of diverse passive and active energy efficient solutions has generated a structure which is one of the most sustainable office buildings in the Netherlands.

The stretched floor plate guarantees a longer facade in order to illuminate every office with daylight, ensuring at the same time an optimum width of the floor plate, or roughly 23 metres for a double-loaded scheme. In addition, the white facade elements work, on one hand, as sun shading; on the other hand, they constitute a daylight redirection device which generate deeper daylight penetration. This double functionality leads to fewer components and, thus, reduced maintenance costs. Finally, thermal glazing allows for the reduction of direct sunlight, in order to reach an optimal level of daylight in the building.

Elongated floorplate

Daylight redirection and shading device

3. Mirai House, Leiden, The Netherlands

The new headquarters building for the Japanese firm Astellas houses both offices and laboratories. UNStudio designed a pleasant, open and transparent working environment for the company’s employees, in addition to an agreeable and welcoming gesture for Astella’s international visitors.

Glass and aluminium are the main materials used in the facade of the building in order to provide a lightweight structure which requires relatively little material usage for its foundation. Lamellas are incorporated on each level of the facade in order to deflect direct sunlight and redirect daylight. The glass panes are coated to further reduce heat load to the interior.

Massing adjustments

Sunlight study

On the northern side of the building, where sunlight is less prevalent, floor-to-ceiling glass is employed, with four-centimetre-deep lamellas. The south and east/west facades respectively are furnished with 30 centimetre and 20 centimetre-deep lamellas. Parapets of 90 centimetres are also employed on these facades in order to further reduce direct sunlight penetration.

Horizontal louvers making sunlight adjustments

Constructed louvers

4. VI Palazzo ENI, Milan, Italy

The pioneering spirit of ENI takes form in the design for the VI Palazzo. The building is designed in the tradition of the company’s own history, accepting the most significant challenge of its times, the capacity of imagining the future. UNStudio picked up the challenge and translated this urge in architecture.

The two most important components for forging the world of tomorrow – research on new renewable energy sources and new communication systems – constitute the heart of the project. The VI Palazzo is a building whose energy efficiency conforms to the Kyoto Protocol, to which ENI has agreed. In a decade’s time, the building will be able to feed energy into the local smart grid, significantly improving the quality of life, for not only the employees working in the building, but also the inhabitants of the surrounding neighborhood. The spatial organisation is inspired by new forms of communication, with a horizontal development in circles, allowing for more simple and effective people flow and work dynamics.

By reducing the height of the buildings in order to increase the number of volume, the exterior surface enlarges. In addition, the open spaces, or atria, in each volume allow further daylight to penetrate the building. Solar shading devices, vertically stacked to the facade, vary in angle and thickness in order to produce an optimum level of sun shading. Inside, a light system adjusts to the amount of daylight, either dimming or turning off when a sufficient amount of natural light is reached.

Massing staggering
Massing adjustment

5. 400 Beethovenstraat, Amsterdam, The Netherlands

The design for the new premises of the law firm NautaDutilh, located in the South Axis area of Amsterdam, sought to create an office building that goes beyond the standard representation of a typical office tower. Ideally employees should feel that they are 'coming home' when they go to work.

Although a seemingly contradictory starting point, this cross pollination of ideas enabled UNStudio to incorporate elements common to residential typologies and to adapt them for the improvement of this working environment.

Sunlight and radiation studies

Facade coverage

The exterior has a systematic and flexible facade approach as a basic set-up. These features were combined according to UNStudio’s solar impact study, creating a seamless, dense changing facade pattern. The envelope was subdivided into horizontal and vertical ‘pixels’ which allowed the design team to create a fully adaptive facade based on four distinct aspects: Good Daylight – No Sun Impact, Good Daylight – Partial Sun Impact, Too Much Direct Sun Impact – Difficult to Block, Much Direct Sun Impact – Easy to Block. The narrow width of the ground floor, which ranges from 14.4 metres to 19.8 metres, allows for daylight gains throughout the whole building.

6. Singapore University of Technology and Design, Singapore

The design of the Singapore University of Technology and Design (SUTD) campus reflects a deep understanding of the changing requirements of learning institutions today. Connectivity, collaboration, co-creation, innovation and sociality are at the core of the non-linear design, which brings together people, ideas and innovation.

The SUTD is a highly sustainable building that utilises specific design strategies to counteract the conditions of Singapore’s tropical climate. Based on orientation and wind studies, natural ventilation principles are applied alongside cooling techniques, covered walkways and louvered facade shading. The massing block orientations are configured to minimise east/west solar exposure with considerations of inter-block shading. Horizontal sun blinds are designed to reduce solar gain, reflect and diffuse daylight into the interior. At the same time, the courtyards enlarge the exterior facade and increase the amount of daylight penetration. Inside, the depth of the corridors is arranged on the basis of the amount of sun and wind exposure.

Facade elements

UNStudio Team: Valentin Goetze, Milena Stopic, Filippo Lodi, Erwin Horstmanshof, Adi Utama