Introduction to lighting design concepts
“Lighting design is a process. Specifically, it is the process of integrating light into the fabric of architecture.”
Lighting is the means to express the desired character of a space.
A successful lighting scheme should be integrated into the design at an early stage. The inclusion of lighting design during the conceptual phases will enable the lighting to enhance a perception of space, reinforce the activity within a space or highlight prominent areas.
Light plays a key role in the design of a visual environment. Work and movement is only possible when we have light to see. Architecture, people and objects are only visible is there is light. Light is an important factor in how we perceive our environment, influencing the way we feel and our reaction to a space.
All about LUX, Lumens, and a few other terms
Luminous intensity is the measure of visible light in a particular direction per sold angle. The SI unit for luminous intensity is the candela cd).
Luminous flux is the measure of the visible light output of a light source (a lamp). The SI unit for luminous flus is the lumen (lm).
Lux and illuminance:
The lux is the SI unit of illuminance and luminous emittance. It measures luminous flux per unit area. One Lux is equal to one lumen per square metre. In most homes an illuminance level of 100lx to 500lx is required. There is guidance for lighting level requirements, table further on in this article.
When we talk about power in lighting, we are looking at the electrical power required by the lamps. The unit of power is the watt (W).
What to think about when you are designing your lighting scheme
Of course, lighting design is more than planning the correct lux level and lighting intensities. It is about the fulfilment of physiological visual requirements, and the emotional requirements of the user. There are three main types of environments that require quite different approaches to lighting design.
- Environments for work, and places that serve the public. These places have a priority of functionality, safety and good communication.
- Environments for exhibitions and sale. These places focus on the exhibit and the users experience of viewing the exhibit.
- Environments for residence or tourism. These places are more personal, looking to create an atmosphere of comfort, relaxation, and so on.
How is the space going to be used and what are the functional requirements of the space? Think about glare, visual comfort and task illumination. When designing for many situations we can refer to the current regulations and standards for the specific lighting requirements for certain tasks.
Recommended light levels for commonly found environments according to the CIBSE guide.
We must establish what activity will take place in the environment, how often and at what time of the day, and how important these activities are. Are these activities limited to specific spaces?
Lighting can have significant effects on human health and behaviour, it is important to consider how your lighting design will impact the users.
Our perception of a space can be significantly affected by lighting. An excellent architectural design can be rendered lifeless and uninspiring with poor lighting. Likewise, a dull or unpleasant space can be significantly improved with the use of clever lighting design.
Don’t forget to consider lighting during both the day and night, both outside and inside. When will the building be viewed outside, when will it be seen/used inside. What impression do we want to make – does the lighting need to be inviting? Atmospheric?
Lighting design can often spiral out of control in terms of costs. It is important to consider the budget and come up with creative solutions to achieve the desired effect whilst keeping costs within budget.
-light and shadow
To take a room from being bland and boring to provide interest and atmosphere it is important to create texture and depth. By designing levels of light you can create well lit areas with soft shadows which will draw the eye to the lit area. This can be used to highlight a rooms main features to become a focal point, be it art on the wall, an ornament, or the dining table.
Light can be used to give the impression that the room is larger. A single pendant light in the middle of the room illuminates the centre but darkens the walls drawing the attention away from the walls. In order to make the room appear larger the walls need to be illuminated with the brightest light, drawing the visitors attention to the surrounding walls, making the entire room visible. Light will also be reflected into the room, giving a good general light to the room.
-direct and indirect light
Direct light, shines directly from a lamp into a room. It is bright and more directional, allowing you to control the area that you want to be lit. Direct light can cause glare which in time can lead to headaches and exhaustion. Anti glare baffles or louvres can help with this.
Indirect light reflects off a surface of a fitting or feature, giving a diffused wash of light onto a surface. This type of lighting can create a relaxed atmosphere since there is no glare and the even lighting reduces the strain on the eye. However, just uses large amounts of indirect light washing across all the walls can create a very bland and boring space so it is important to experiment with a combination of light and shadow to offer interest.
-colour of light
Light can be seen in a variety of colours and has a huge impact on your lighting design. Generally speaking there are cold colours and warm colours. Cold colours tend to have more blue inside them, where warm colours have more yellow. The different colours can be used to create different environments but also used for different purposes. Daylight is a cold light, and cold lighting is used in offices to create a natural daylight effect – also to achieve a good lux level for the task at hand.
Warm lighting is often seen in residential settings. A cold colour looks good when it is used at high lighting levels, whereas the warmer colour lighting looks better at low levels of light. In residential settings, you would often see the colder lighting used in areas such as bathrooms and kitchens where brighter lighting is required, and warm colours in bedrooms and living rooms.
Task lighting is light provided for specific tasks being done in a space. Some rooms will require different light in different areas. For example, a kitchen will require extra lighting to the worktop when food is being prepared, and a living room may require extra lighting in a seating area for reading.
It is sometimes best to consider your task lighting requirements before the overall lighting.
Ambient lighting can be provided in two main ways, with direct downlighting or uplighting, where pendant luminaries provide upward light that reflects from the ceiling.
-controlling the light
There have been great advancements in technology when it comes to lighting and there is now more choice than ever for controlling the light. Consider switching options, dimming, wireless control, remote control and so on. How and where will the lights be controlled and how will this effect the user experience?
The most important element of the lighting design is to ensure it is considered at an early stage of development. Incorporate the lighting into the architecture to produce a scheme that is well balanced. There are many factors to take into account when developing the lighting scheme, not only regulations and general standards but never forgetting the user, and the purpose of the space.
For more information and further ready please look at the links below:
Handbook of Lighting Design – Rudiger Ganslandt & Harald Hofmann