The Psychology of Interior Lighting: Daylight

In Part 1 of my psychology of interior lighting series, we discuss the importance of daylight and how to best use it to improve our homes and our well‑being.

If you have followed my previous psychology of design lessons on space, you might be wondering what more there is to say about light, as all of my lessons so far have, at least in part, focused on light. Light is probably the most fundamental to any interior design. It can be used to increase space (Lesson 1) and has the potential of making exactly the same paint colour appear entirely different in two rooms facing in different directions (lesson 3). In this series, I want to take a closer look at lighting and share more specific ways of understanding and using light to achieve the mood you are envisioning. The first lesson will once again focus on daylight.

Liljencrantz Design via Design Miilk
Designer Tommaso Spinzi's Loft Apartment, Photography by Lorenzo Pennati (via Yellowtrace)
Design by Gundry Ducker, Photography by Andrew Mereditch (via Get Clever)
Athena Calderone's Kitchen

Psychology Insight

We don’t need the government to prescribe Vitamin D to boost the immune system after a pandemic to know that light is good for our health. Science can only confirm what we already know intrinsically: humans are drawn to the light in the same way that plants grow towards the sun. Light can affect our mood — the English language gives vivid expression to that: we can be “feeling in the dark”, be “in a black mood” or “see the light”.

The nerve centres in our brain are stimulated by the light that enters our eyes, which affects how excited or relaxed we are. Light also regulates our biological clock by affecting the pineal gland, which is responsible for the production of the sleep hormone melatonin. In other words, light is crucial to making us feel awake. Studies that compared participants based on the distance from natural light of their work environment found that when humans are deprived of natural light they become depressed and lethargic.

Guillermo Santomas' Barcelona Home (via Sight Unseen)
Visualised by Kseniya Romanova (via Home Designing)

Lesson 1

Making The Most Of Daylight

Like in the previous lessons, my first recommendation is to spend some time getting to know the room and watching how the light moves around the room throughout the day.

Dark Rooms

If your room is particularly dark you may want to apply a couple tricks to maximise the light. Start by ensuring that the light comes through as uninterrupted as possible by not having too much going on around and in front of the window. Secondly, you can maximise the reflection of light through a couple of tricks:

  • Install a big mirror, preferably on the other side of the window for the greatest reflection. Alternatively, a glass picture frame will have a very similar effect. The same effect can also be achieved by placing mirrored furniture.

    Bateaumagne Architecture
  • Install narrow panels of glass (or mirror) on the flanks of either side of the window to intensify and reflect the light into the room.

  • Pay attention to where the light hits the floor and look for ways to reflect the light from there. Avoiding carpet or rugs might be a good idea as they absorbs light. If you use something glossy it will reflect the light directly onto the walls and ceilings, while a matt surface scatters the light softly around the room.

    Glossier Store LA (via Bloomberg)
    Aesop Store Concept by Alexander Pankow (via Behance)

Direct Light

Direct light via a ceiling window or a South-facing room can sometimes create dark corners and harsh shadows, in which case, it might be appropriate to redistribute the light.

  • You can do this by using a matt surface on the floor that diffuses the light.

    Mary Duggan Architects
  • You can place plants around the window or install blinds and sheer curtains to filters the light.

    Nueva Carolina Studio & Event Space in Madrid by Cordero Atelier
    Villa Pestarini by Franco Albini

The Effect Of Colour On Light

When it comes to maximising daylight, colour can be pretty effective at that.

    Psychology Insight

    While light might look white to the bare eye, it is actually made up of the whole spectrum of colours: red, yellow, green, blue, indigo and violet.

    The visibile light spectrum
  • If light hits a red wall, most colours will be absorbed except for the red which is reflected. The lighter the paint, meaning the closer it is to white, the higher the reflectance of light will be. To that matter, reds, oranges, browns, and black are colours that suck up daylight and don’t bounce it back into the room. Pale greens, blues, and purples, on the other hand, can be used to amplify daylight.

    Design by Gundry Ducker, Photography by Andrew Mereditch (via Get Clever)
    The Webster by David Adjaye via Elle Decor Italia
    Concept Visualisation by Katarina Rulinskaya (via Coco Lapine)
    Photography by Pia Riverola
  • I’ve already covered colour and light in a previous lesson, which I highly recommend for the extended version on how to use colour to affect the brightness of a room.

Wondering how you can apply the psychology of daylight to your space? Get in touch or book an initial consultation via my Design Services page!

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The Psychology Of Space: Perception


The Psychology Of Space: Proportion


The Psychology Of Colour: Considering Light

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