Light and Architecture

"Natural light is not static. You can feel the day passing and the clouds drifting by. And then there’s what I call the 'Magritte moment.' It’s when the light fades, and you turn on the lights. The illumination brings the room back to life."

– Renzo Piano

Moroccan Mashrabiya

Credit  :  Pinterest

Light is an essential element in architecture and interior design. It plays an undeniable role in our well-being within a space. Over the years and centuries, its importance has evolved; today, it takes center stage, with a clear distinction between different types of light.

There are two main categories of light: natural light and artificial light.

Natural light is treated differently depending on whether it is direct sunlight or indirect or secondary light (also known as daylight, created by the reflection of sunlight on other surfaces).

Light Well

Credit  : Pinterest / Spezzatura-Eleganza

Sunlight is a white, visible light that has a beneficial effect on humans, both psychologically and physiologically.

This is why it’s crucial to consider light when designing a building, particularly by paying close attention to the orientation of rooms and windows, carefully planning room proportions, and playing with the shadows cast by surrounding structures and vegetation. If we come into the picture after construction, it’s still possible to recreate the characteristics of sunlight and daylight through artificial lighting and creative use of materials.

Artificial light, which originally came from fire via candles and fireplaces, experienced a true boom in the 19th century with the advent of electricity. However, this breakthrough was so significant that natural light was neglected for a few decades. It seemed far more convenient to simply flip a switch. We had forgotten that natural light offers variations throughout the day and across the seasons, providing a comfort that artificial light still cannot perfectly replicate. Natural light accompanies our daily rhythm, offering sensory comfort and well-being. It breathes life into the rooms of a house, changing subtly every day, and creating a connection to the outside world.

Moreover, unlike artificial light, natural light is free and environmentally friendly.

 I. The use and mastery of natural light

Shower under light well

Credit  : Pinterest / Clem around the Corner

A source of well-being, mastering natural light is one of the fundamentals of architecture. Depending on where we are on the planet, the challenges we face will differ, and we must adapt the way we manage light accordingly.

For instance, in countries near the equator, the goal is often to avoid direct sunlight while still preserving daylight. Conversely, in Nordic countries, the priority is to maximize brightness. Beyond illumination, sunlight also provides warmth, which can either be sought after or avoided depending on the season and geographical location.

Here are some examples of how we manage natural light by region of the world

Japanese rice paper screens

Credit : Casadeco

In Asia and the Middle East, efforts are made to shield spaces from direct sunlight while preserving daylight. To achieve this, Asian cultures have traditionally built homes in concentric layouts, distributing rooms based on their specific light requirements.

Additionally, they use rice paper screens on windows, which block direct rays while allowing light to filter through, creating a soft, diffuse glow. They also favor varnished or lacquered furniture, where the reflective surfaces enhance brightness within the space.

In the Middle East, mashrabiya screens are preferred, allowing rooms to be ventilated without letting direct sunlight in. This approach is also highly aesthetic, as the intricate designs create a playful interplay of light and shadow while providing protection from heat (e.g., the Institut du Monde Arabe in Paris).

Additionally, matte finishes like tadelakt are often used. Unlike lacquer, tadelakt reflects little to no light, helping to minimize the sun's impact as much as possible.

Moucharabieh

Credit : Pinterest / ARchZine FR

Credit : ArchDaily

Shutters & Pergola Designed by Erginoglu & Calislar

Credit : Pinterest / Contemporist

In Europe, the interplay with the seasons greatly influences how natural light is managed. Window orientation is crucial, with a preference for south-facing openings. Vegetation then complements the changes in light and heat throughout the year. For example, a glass roof can be installed on the southern side of a house, paired with a pergola covered in deciduous plants, such as wisteria. In winter, the plant sheds its leaves, allowing maximum light to enter, while in summer, the foliage provides shade and protects against excessive heat.

Fun fact: Until 1926, taxes in France regulated the size of windows and doors, which is why only buildings constructed after this date tend to have larger openings.

Innovation continues to advance how we manage natural light. While curtains, shutters, and blinds have become standard, we are now seeing an increasing use of skylights and “smart” glazing designed to meet the needs and preferences of residents.

Modern glazing materials, equipped with crystals, can naturally adapt to sunlight levels, automatically regulating heat and natural light intake. Similarly, shutters are now often integrated with smart home systems, allowing for automated, programmable adjustments to their position.

 Luminosity according to positioning :

Natural light entering through the veranda and the ceiling glass windows

Credit : Filloneau Vérandas

• North-facing windows: Provide consistent, diffuse light throughout the year. However, discomfort may arise in summer during early mornings or late afternoons when low-angle rays can cause glare.

• East-facing windows: Difficult to control during sunrise, as the rays are at their lowest angle. This orientation offers limited sunlight in winter but receives more than south-facing windows in summer. Overall, it may not be the most practical option.

• West-facing windows: Similar to east-facing windows, discomfort can occur, but at sunset instead. Additionally, west-facing rooms experience intense sunlight in the afternoon during summer, leading to potential overheating.

• South-facing windows: The ideal orientation for light and sun management. They provide maximum sunlight in winter and minimal exposure in summer, as the sun is higher in the sky.

II. Light as a material in architecture and decoration

Recent architectural innovations, such as concrete beams and load-bearing structures, have transformed exterior walls into non-structural elements, functioning more as cladding. This shift allows for greater flexibility in designing openings and controlling how light enters the space. The aim of light-focused architecture is to guide natural light to specific areas—capturing, directing, and redistributing it effectively.

To achieve this, both the orientation of openings and the surrounding environment, such as vegetation or nearby topography, must be considered to maximize direct or indirect light indoors.

Here is a non-exhaustive list of features that can be used to manage light and its intensity, depending on the seasons and times of day, to prevent glare or overheating in a room:

Sheer fabric and diffused light

Credit : Pinterest / Côté Maison

• Blinds

• Lattice screens

• Curtains

• Pergolas

• Mashrabiya screens

• Special glazing

• Stained glass

• Vegetation

• Canopies

• And more…

Light is not visible in itself but becomes perceptible through its reflection on surfaces and objects. We refer to direct light when the rays are reflected directly off a surface, indirect light when the reflection occurs by rebound, and diffused light when the rays are filtered through a translucent material or one that only allows part of the rays to pass through.

This is why it's also important to play with the types of materials used. The shinier the material, the more it will reflect light and increase its intensity in a room. Conversely, matte materials will diffuse less light by rebound.

Lastly, color and light are deeply interconnected in architecture. There is no color without light. The more intense the light, the bluer it will appear (which is why the sky looks intensely blue when the sun is at its zenith, and the sun appears white). On the other hand, when light is weaker—meaning the rays have to travel through a longer path—the colors transmitted will be more orange. Additionally, a veil (such as rain or pollution) causes diffraction of the rays, and all the waves will arrive equally, resulting in white light.

In short, this principle applies to artificial light as well: the stronger the waves, the cooler the color, while weaker waves bring warmer colors to the light, and thus to the objects on which it reflects.

Conclusion: Playing with artificial light and decoration

Play of artificial lights, recessed LEDs

Credit : Pinterest / Deavista.fr

It is not always possible to control natural light, especially when working with an already built space. Artificial light can help complement the need for brightness, thus optimizing daylight.

Through careful selection of materials, colors, devices, lighting fixtures, and especially the choice of light bulbs, we can optimize the luminous comfort of a space and even bring life to the night.

As interior architects, we enjoy incorporating multiple light sources, particularly in the living room, which is the central space of the home. This approach allows us to create different lighting atmospheres depending on our moods.