WHAT IS GOOD DAYLIGHTING?
As we begin to understand daylighting, we can also start to think about how we will use the components of daylight – direct sunlight, skylight, and reflected light – to deliver good daylighting in our buildings.
The assessment of whether daylighting is ‘good’ or not depends on how a space is used, together with a range of objective and subjective criteria. Our experiences of, and attitudes toward, daylight are personal, which influences how we design for daylight.
How should we define daylight in a way that its positive attributes can be site specific and, at the same time, beneficial for a wide range of building users?
KEY LEARNINGS
- Understand five key considerations for ‘good’ daylighting.
- Recognise how the European Standard EN 17037 can help to create a tangible target.
- Develop your appreciation for the ‘emotional quality’ of daylight.
How do we determine if daylighting is ‘good’ or not? Legislation and standards provide good foundations for daylighting design. Often, however, they don’t consider all of the factors influencing the experience of daylight in a space, and how this can vary through different times of the day/year and weather patterns.
It is important to think beyond typical standards to ensure that the chosen solutions truly achieve ‘good daylighting’. Accounting for the following is a good starting point for meeting a project’s needs, though the details will vary from project to project.
- Requirements of national building regulations/codes, and/or voluntary schemes and rating systems.
- Visual needs of occupants and the space (specific task needs including study, play, safe navigation, contact with nature and context through views).
- Non-visual needs of the occupants (entrainment of circadian rhythm, mood, focus, healing).
- Impact of daylighting solutions on energy performance, thermal comfort and sustainability (heat gains, materials).
- Experience of daylight within a space (influencing perception of space, creating a desired atmosphere, aesthetic composition of light).
Photography: Rasmus Norlander. Architects: GNWA
Using EN 17037 to convert 'considerations' to a tangible target
Traditionally, standards giving recommendations for natural daylighting did so in the context of artificial lighting provision, and how the two performed together.
The publication of EN 17037 in 2018 marked the first time that a standard dealt exclusively with the design for, and provision of, daylight in buildings. In some countries, no standard for daylighting existed, meaning EN 17037 offered an all-new type of guidance for designers, architects, builders, and occupants.
To achieve its aim of improving the comfort of building users through the benefits of daylight, EN 17037 covers four different areas of performance.
You might already be familiar with designing to provide daylight, but the three additional aspects covered by the standard significantly extend the scope of daylighting design compared to previous best practice. In doing so, it becomes a strong step towards covering all five of the daylighting considerations listed above.
Daylight phenomenology and designing for the senses When both client and architect have a vision, built on a foundation of sound daylighting principles and practical goals, there is more opportunity to play freely with the way daylight is used to create composition and atmosphere in a space – without compromising the project’s practical needs for light.
‘Daylight as a phenomenon’ – or the experiential, emotional quality of daylight within a building or architectural space – is by far the most subjective aspect of designing with daylight. Arguably, it is also one of the most important experiential factors for building occupants and users.
Though hard to measure quantitatively, the atmospheric quality of light in any space will have a big impact both functionally and aesthetically, bringing immense value to a project.
Inspiring emotional and physical well-being It is hard to argue that great building designs – no matter the project type – inspire an emotional response from users. Throughout history, natural light has played a big part in creating these kinds of architectural experiences. That response may be a sense of a connection with nature, of reverence, of awe, of playfulness or surprise, or simply a sense of calm.
From the long shadows of Alhambra’s colonnades to the god-like light beam of the Roman Pantheon to the dappled light of Jean Nouvel’s modern Louvre of Abu Dhabi or perhaps just the soft wash of afternoon light welcoming you home at the end of a long day; thoughtful use of natural light can be transformative to the way any building is experienced and remembered.
Of course, each project requires its own set of daylighting solutions, derived from specific context, a client’s needs and wishes, and the parameters of budget, time and building materials. There is no single right answer or rule of thumb that solves every design problem, but enhanced occupant wellbeing and a transformative experience of daylight always begins with a goal in mind.
How do building users benefit from good daylighting? Armed with an understanding not only of what daylighting is, but also what good daylighting can provide for building users, it is possible to start imagining the outcomes you might want to aim for in a project. That starts with the visual needs of building occupants, achieving the right amount of light for specific tasks while ensuring visual comfort.
How do building users benefit from good daylighting? Armed with an understanding not only of what daylighting is, but also what gooddaylighting can provide for building users, it is possible to start imagining the outcomes you might want to aim for in a project. That starts with the visual needs of building occupants, achieving the right amount of light for specific tasks while ensuring visual comfort.
» Read on: Understanding visual needs
Photography: Brendan Austin. Architect: Jørn Utzon Image source