Lighting is one of the most powerful and underrated elements in interior design. It can alter the color of finishes, the look of textures, the apparent size of a space, and the sense of comfort in a room. It can make a well-designed space with nice finishes fall flat. And good lighting is not just about more light, but about lighting control, multiple lighting layers, lighting direction and intent.
Learning the fundamentals of lighting design means that aspiring and emerging designers are better equipped to create spaces that are harmonious, livable, and uplifting. Lighting should be designed, not just applied.
Why We Think of Lighting as a System, Not as a Fixture
Lighting is often thought of as just selecting some fixtures and calling it a day. Actually, lighting is a system and has different levels that need to be incorporated. Usually just a ceiling light does not create a pleasant space. It flattens everything out, creates hard shadows, and isn’t flexible.
In a lighting system, one or more light sources work together to fulfill one or more functions. Light can be used to illuminate a space, to perform tasks, to enhance the aesthetic of a space, and to draw attention to a focal point. Multiple layers of light are necessary for visual interest and flexibility.
Lighting systems, not products, is the first major mental step into professional lighting design.
The Three Main Layers of Light
There are 3 layers that make up the composition of functional lighting. Each space, when adequately illuminated, will include each of the three.
The first one is ambient. That’s the basic level of lighting that you need in order to navigate and see what the space is. So, this could be overhead lights, recessed lighting, indirect cove lighting.
The third type of lighting is task lighting, which provides direct light for a particular task or activity. It offers light exactly where you need it, giving you the ability to perform tasks more accurately. Common examples of task lighting include desk lamps, under-cabinet lighting in the kitchen, and floor lamps that are positioned next to a chair or other reading area.
Accent lighting: This is directional or decorative lighting used to accentuate objects, textures, or architectural elements. Wall washers, picture lights, and shelf lights are examples of accent lighting.
The layers, when put together, help to give depth to the space instead of a 2-D effect.
The Basics of Ambient Lighting
Ambient light should be smooth, glare-free and comfortable. It’s about illumination, not effect. It establishes the overall light level against which all other light layers are compared.
Good ambient lighting usually comes from more than one light source. Instead of a single light in the middle of the ceiling, you might have multiple lights spread across the ceiling or you might have indirect lighting. This results in more even illumination and less dramatic shadows.
Another type of lighting is indirect ambient lighting, where the light bounces off of the ceiling or walls. This is a very comfortable type of lighting since it reduces contrast. It can be used in living spaces and bedrooms, where a soft visual environment is preferred.
The ambient lighting should be light enough that you can move around without tripping, but not so light that you don’t need layered lighting.
Task Lighting for Function and Comfort
Specific tasks require specific lighting. Reading, cooking, grooming, and close-up work demand more concentrated and brighter lighting than walking around the room.
Task lighting should be:
The light should be: Directional, Glare-controlled, Placed to minimize shadows from the user
Rather than pure lumens, placement is key. Even a very bright light can still result in bad visibility if the user’s body is in the way of the light.
Each task lighting should be switched separately wherever feasible to enable users to add lighting where and when they need it without overlighting the entire space.
Accent Lighting and Visual Focus
Accent lighting provides emphasis and makes spaces more interesting and dramatic. It also adds depth and provides visual interest. Spaces with no accent lighting can be flat and boring.
Accent lighting is used to draw attention to:
Artwork Textured walls Architectural niches Display shelves Plants or sculptures
Accent lights are usually more directed and a little more intense in comparison to the object and the ambient light. This contrast draws attention to it. But multiple points of accent causes distraction.
Be selective with key highlights.
Light color temperature is a way to describe the color characteristics of light, ranging from warm yellowish tones to cool bluish tones. In essence, it’s a measure of how “warm” or “cool” the color of the light appears. The temperature of light is measured in degrees Kelvin (K), with higher temperatures indicating whiter, bluer light and lower temperatures signifying yellower, warmer light.
Color temperature is the warmth, coolness or neutrality of light. It has a huge effect on the mood of the scene and the look of materials.
Now, to apply these color temperatures to a bit of practical psychology: Warm white light makes people feel calm and is used in homes and hotels. Neutral light is used in spaces that are for multiple purposes. Cool light gives a space a sort of energized air and is used in areas that require focus.
Color and lighting temperature are related: warm light makes warm colors (wood, earth tones, etc.) look great, while cool light makes cool colors and high-contrast colors look great.
Uniformity in a room is desirable. You should not combine different color temperatures in the same viewing field, unless you want to.
Light Intensity and Brightness
It’s a question of brightness distribution rather than just the absolute brightest. Over-lighting is just as bad as under-lighting. Too bright makes glare, eye-strain, and flatness.
Rather than a single high-intensity source, several medium-intensity sources. Shadows and readability both benefit.
Dimmer switches are one of the most powerful lighting design devices available. They enable the adjustment of light levels according to the hour of the day, task at hand, or atmosphere desired. And without the need to purchase new lighting fixtures, they provide the ultimate in flexibility and usability.
Lighting Control – Direction and Shadow
The direction of the light influences the position and strength of shadows. Shadows influence the way texture and shape are read. Frontal light makes shadows disappear and forms look flat. Side light makes texture appear. Rim or up-light makes things look dramatic. Light shining from below makes things look spooky.
For instance, if you’re shooting stone or brick, you’ll want to light it at an angle to bring out the texture. With mirrors and other shiny surfaces, you need to consider the angle to prevent glare.
Don’t just consider where the light will shine, consider where the shadows will fall.
Lighting in a Room and What it’s Used For
Meanwhile, different lighting proportions suit various types of rooms.
For example, a living room might require a combination of lights that can be dimmed to create a cozy atmosphere for reading or watching television and brighter for entertaining. In a bedroom, you might want an overall soft glow with more focused reading lights for each person. In a kitchen, you would want intense light where you do food preparation, with overall lighting to illuminate the rest of the room. In a bathroom, you would want very even lighting across your face for applying makeup, along with overall lighting. At a desk, you would want light that shines directly on your work without causing glare, with overall lighting that is relatively constant.
The function of a space should dictate the priority of the lighting. Ambiance isn’t a sole consideration.
“Fixture Scale and Placement”
Remember to choose lighting that’s proportional to the room and ceiling. Large light fixtures in small rooms make the space feel cramped. Conversely, fixtures that are too small in a big room get lost.
When to use placement rules:
Locate fixtures over the center of the working areas, not necessarily the center of the room. Locate repeating fixtures on the same axis as architectural features or pieces of furniture. Use equal spacing with recessed fixtures. Locate very bright fixtures out of the line of sight.
Visual alignment conveys organization and credibility.
Natural Light Incorporation
Consider natural light as a component of the lighting design. The orientation, amount, and time of day of natural light influence the artificial lighting requirements.
Lighting in well-lit spaces calls for additional control by curtains, blinds, filters, etc. and artificial light should enhance, not fight, the daylight.
Take note of how natural light varies during the day and design supplemental lighting to provide equalization during the nighttime.
- Widespread Lighting Design Errors
There are some errors that you often see in novice projects.
Some of the most common mistakes include: depending on a single overhead fixture; not using task lighting; mixing different color temperatures; over-lighting a small space; locating lights where they’ll cause glare; not installing a dimmer switch; and lighting only on the horizontal plane instead of the vertical plane.
One other mistake people make is to consider lighting after they have arranged the furniture. Lighting should be a design element that is considered in the same way as layout.
Practical Lighting Plan
An easy planning technique that boosts outcomes is:
- Determine what will be going on in the room
- Mark the task lighting locations
- Add general lighting as a secondary consideration
- Add accent lighting as a tertiary consideration
- Check for glare and shadowing conditions
- Add dimming to as much of the lighting as you can
We need to decorate a function after it has been defined.