Lighting System

Commercial Interior Space Designing-II 4(1+3)

Lesson 9:Lighting arrangement for public building

Lighting System

Lighting design as it applies to the built environment, also known as 'architectural lighting design', is both a science and an art. Lighting of structures must consider aesthetic elements as well as practical considerations of quantity of light required, occupants of the structure, energy efficiency and cost. For simple installations, hand-calculations based on tabular data can be used to provide an acceptable lighting design. More critical or optimized designs now routinely use mathematical modeling on a computer.

In some design instances, materials used on walls and furniture play a key role in the lighting effect. Dark paint tends to absorb light, making the room appear smaller and more dim than it is, whereas light paint does the opposite. In addition to paint, reflective surfaces also have an effect on lighting design. Surfaces or floors that are too reflective create unwanted glare

Lighting or illumination is the deliberate application of light to achieve some aesthetic or practical effect. Lighting includes use of both artificial light sources such as lamps and natural illumination of interiors from daylight. Day lighting (through windows, skylights, etc.) is often used as the main source of light during daytime in buildings given its high quality and low cost.


Daylighting is an important method of lighting that is as old as time. Daylighting is simply designing a space to use as much natural light as possible. This decreases energy consumption and costs, and requires less heating and cooling from the building.

Daylighting has also been proven to have positive effects on patients in hospitals as well as work and school performance. Due to a lack of information that indicate the likely energy savings, daylighting schemes are not yet popular among most buildings

Health effects

It is valuable to provide the correct light intensity and color spectrum for each task or environment. Otherwise, energy not only could be wasted but over-illumination can lead to adverse health and psychological effects. Radiation and UV Rays UV-A rays are detected at a certain intensity based on the distance measured from window, time and incidence angle.

In the indoor environment, the distance from window is the most significant factor in the determination of UV intensity. Radiation can do harm from any angle and thus incidence angle is another factor for consideration.

The solution might be achieved in the selection of building materials, design of facades, and space organization. Function glasses can dramatically reduce the transmitted amount of UV into the building. With an overhang or vertical fin, appropriate solar control is required to block direct sun into the interior.

Artificial lighting

represents a major component of energy consumption, accounting for a significant part of all energy consumed worldwide. Artificial lighting is most commonly provided today by electric lights, but gas lighting, candles, or oil lamps were used in the past, and still are used in certain situations. Proper lighting can enhance task performance or aesthetics, while there can be energy wastage and adverse health effects of poorly designed lighting. Indoor lighting is a form of fixture or furnishing, and a key part of interior design. Lighting can also be an intrinsic component of landscaping.

Lighting fixtures come in a wide variety of styles for various functions. The most important functions are as a holder for the light source, to provide directed light and to avoid visual glare. Some are very plain and functional, while some are pieces of art in themselves. Nearly any material can be used, so long as it can tolerate the excess heat and is in keeping with safety codes.

An important property of light fixtures is the luminous efficacy or wall-plug efficiency, meaning the amount of usable light emanating from the fixture per used energy, usually measured in lumen per watt. A fixture using replaceable light sources can also have its efficiency quoted as the percentage of light passed from the "bulb" to the surroundings. The more transparent the lighting fixture is, the higher efficacy. Shading the light will normally decrease efficacy but increase the directionality and the visual comfort probability.

Last modified: Monday, 19 December 2011, 6:35 AM