1. LIGHTING DESIGN CONSIDERATIONS
PRESENTATION BY
SANDAL USMANI
MOMIN MOHAMMAD ZAKI
2ND YEAR – M. ARCH
BUILDING SERVICES
FACULTY OF ARCHITECTURE & EKISTICS - JAMIA MILLIA ISLAMIA
GUIDED BY
AR. P. PRAKASH
AR. RAVI JAIN
2. Lighting Design
“Design” is the science and art of
making things useful to humankind;
and lighting design is the application of
lighting—including daylight when it is
specifically used as a source of
lighting—to human spaces. Like
architecture, engineering and other
design professions, lighting design
relies on a combination of specific
scientific
principles,
established
standards and conventions, and a
number of aesthetic, cultural and
human factors applied in an artful
manner.
Lighting Design
3. Lighting Quantity
Task Illuminance
Design
Considerations
Implementation
Economic / Cost Consideration
Energy / Sustainability
Lighting Quality
Light Distribution, including:
• Task and ambient lighting
• Day lighting integration
• Light pollution and light trespass
Space and Workplace
Considerations, including:
• Flexibility
• Appearance of the space and
luminaires
• Color appearance
• Luminance of room surfaces
• Direct glare
• Reflective glare
Lighting on People and Objects,
including:
• Modeling faces and objects
• Surface characteristics
• Points of interest
FORMAT OF PRESENTATION
4. Lighting Quantity
For general lighting purposes,
the recommended practice is
to design for a level of
illumination on the
working plane on the basis of
the recommended levels
for visual tasks given in CODES
(NBC) by a method called
‘Lumen method’. In order to
make the necessary detailed
calculations concerning the
type and quantity of lighting
equipment necessary, advance
information on the surface
reflectance of walls, ceilings
and floors is required.
Task Illuminance
Task Illuminance describes the amount of light falling on a
surface. It has two components.
1. Amount of Light –
(based on usage or multiple usage of a space)
After detailed study and research CODES – provides
values
&
2.If the surface is horizontal - horizontal illuminance
if the surface is vertical - vertical illuminance
Some tasks though are at an angle, such as reading a book
in a hospital bed.
Design Consideration – 1. Lighting Quantity
5. Lighting Quality
Lighting
profoundly
affects many human
reactions
to
the
environment.
These
human reactions range
from the obvious, such as
the dramatic beauty of an
illuminated landmark or
the emotional response
of a candlelight dinner, to
subtle impacts on worker
productivity in offices or
sales in retail stores.
Light Distribution, including:
• Task and ambient lighting
• Day lighting integration
• Light pollution and light trespass
Space and Workplace Considerations, including:
• Flexibility
• Appearance of the space and luminaires
• Color appearance
• Luminance of room surfaces
• Direct glare
• Reflective glare
Lighting on People and Objects, including:
• Modeling faces and objects
• Surface characteristics
• Points of interest
• Sparkle
Design Consideration – 2. Lighting Quality
6. Lighting Quality
• Task and ambient lighting
Task lighting systems independent from the space’s general lighting systems (serving specific
task) are found in building types for instance, the display lighting in retail stores is a form of
task lighting. Similarly, task lights are used in industrial manufacturing and assembly, health
care, residential lighting, and many other interior lighting applications.
Options include
– indirect luminaires mounted atop cobinetry or workstations
– Suspended luminaires
– Recessed luminaires
Ambient Lighting:
Task lights can’t light the balance of the room, and thus
some other type of lighting system is needed to produce
the ambient illumination in the room.
Design Consideration – 2. Lighting Quality / Distribution
7. Lighting Quality
Task – Ambient Lighting produce energy
savings in three ways:
•Locating the light source close to the task
most efficiently produces the illumination
levels needed for the task.
•Task illumination levels don’t have to be
maintained uniformly thorugh out the space,
so ambient levels can be lower.
•Some occupants won’t use their task lights,
and empty offices or workstations with absent
occupants don’t have to be fully illuminated
Design Consideration – 2. Lighting Quality / Distribution
8. Lighting Quality
Day lighting Integration
Practice of using windows, skylights and other forms
of fenestration to bring light into the interiors of
buildings using various means.
Incorporating day lighting in the lighting design can
be done by:
•Proper control of the fenestration luminance
•Daylight sensing and compensation control systems
which allow adjustments to electric electrical lighting
system
•Glare controls should also be incorporated in the
design
•New techniques for “piping” light into interior
spaces can allow sunlight and daylight to furnish a
higher percentage of illumination requirements and
more uniform distribution
Design Consideration – 2. Lighting Quality / Distribution
9. Lighting Quality
Light pollution & light trespass
In outdoor lighting, electric light may
illuminate adjacent properties which
become offensive if unwanted is known as
light trespass.
Electric lights emitting light upward o
reflecting light upward cause a condition
called light pollution which causes moisture
and particles in the air to glow at night.
Several steps to minimize light pollution & light trespass
Use night lighting only when and where necessary
Use the minimum amount of light needed rather than the maximum
Use sources with cutoff optics that restrict light to the intend area of
illumination
Use more sources, each of lower wattage, to improve uniformity in the intended
illumination area and minimize trespass into adjacent areas.
Design Consideration – 2. Lighting Quality / Distribution
10. Lighting Quality
Space and Workplace Considerations,
including:
• Flexibility
• Appearance of the space and luminaires
• Color appearance
• Luminance of room surfaces
• Direct glare
• Reflective glare
Design Consideration – 2. Lighting Quality / Space & Workplace
11. Lighting Quality
• Flexibility
Advance lighting designs should be flexible enough to ensure that:
Lights operate where needed, and are off where not needed, as people move
around within a space and use rooms in different ways.
Spaces used for “hoteling” – the occasional or transient use of a workspace –
remain dark unless needed.
The lighting space system can be rapidly reconfigured to match a changed
floor plan or accommodate a different space use, and still operate at
maximum energy efficiency.
The lighting system permits multiple uses and on-demand flexibility in
multiple-use spaces such as conference rooms and modern A/V classrooms.
Design Consideration – 2. Lighting Quality / Space & Workplace
12. Lighting Quality
Appearance & Space of luminaires
Luminaire efficiency and the ability to use efficacious sources have become
increasingly important criteria for selecting luminaires.
Designer should find lighting systems that embody the project’s style or
aesthetic but to do so using high-efficacy sources and efficient principles.
For instance, choose luminaire that “hide” light source but avoid such as
crystal chandeliers that require lamps with bare incandescent filaments.
Design Consideration – 2. Lighting Quality/ Space & Workplace
13. Lighting Quality
The appearance of color
both in terms of
color rendition (CRI-Colour Rendering Index)
Correlated colour Temperature (CCT)
are important in the overall feeling of the space, and in some instances can have a
dramatic effect on visual tasks.
Design Consideration – 2. Lighting Quality/ Space & Workplace
14. Lighting Quality
Color Rendering Index (CRI) describes how a light source makes the color of an object
appear to human eyes and how well subtle variations in color shades are revealed.
The CRI is a scale from 0 to 100 percent indicating how accurate a "given" light source
is at rendering color when compared to a "reference" light source. The higher the CRI,
the better the color rendering ability. Halogen is considered the “reference” light
source and has a CRI of 100.
CRI of 100 in an LED source has not yet been developed. CRI in the 90’s is possible
but very expensive.
Fluorescent lamp sources are considered very poor in CRI running in the low 70’s. A
CRI index >80 is considered very good.
Design Consideration – 2. Lighting Quality / Space & Workplace
15. Lighting Quality
Correlated Clolour Temperature
For good visual comfort, light needs to
have the right color and quality.
Light can feel cool or warm. This is
quantified by the "color temperature"
and measured in degrees Kelvin. The
higher the color temperature, the bluer
the light is. This may seem counterintuitive, as we think of blue as a
"cooler" color than red, but it comes
from the physics of black body
radiation.
People generally prefer
bright light to be bluer, like daylight,
while they prefer dim light to be yellow,
like candlelight.
The color temperatures of daylight and
various common light sources are
below.
Design Consideration – 2. Lighting Quality / Space & Workplace
16. Lighting Quality
Luminance of room surfaces –
Periodic trends in interior design introduce dark paints and finishes. These trends
contribute to difficulty in producing energy-effective design by increasing lighting
requirements to raise surface luminance into the comfortable range.
Lighting designer should:
Encourage the use of high diffuse reflectivity (light colored) surfaces and minimize the
use of dark surfaces.
Use computer modeling to ensure that the average room surface luminance is at least
10% of the task background.
With indirect lighting systems, use computer calculations to check for uniformity and
try to maintain 10:1 luminance ratio or better.
Design Consideration – 2. Lighting Quality / Space & Workplace
17. Lighting Quality
Direct Glare
. Caused by a view of the light source, often with high contrast to the surroundings.
Glare is associated not just with lamps, but also with daylight, especially when one is
exposed to low angle, direct sunlight.
Be concerned
– more about the glare caused by lamps, lenses and other overly birght sources of
manmade lights
– less about glare of sunlight and small point sources
– most concerned about sources of glares in relation to the stationary tasks when
building occupants cannot easily relocate themselves or their tasks
Design Consideration – 2. Lighting Quality / Space & Workplace
18. Reflective Glare
Lighting Quality
Have long been associated with gloss-coated paper, pencil paperwork and computer
CRT (cathode ray tube) screen.
Indirect lighting, by creating a diffuse and uniform illumination has been advocated as
solution.
Can create specular reflections that can cause glare reducing comfort or disabling the
worker’s vision in particular areas.
Reflective glare - when system has been optimized to reduce glare – then consider:
modifying the task to eliminate remaining glare problem such
as use of flat screen CRT or active matrix.
Use of ink rather than pencil
Use of matte-coated or uncoated paper rather than gloss coating paper.
Changing finishes of polished floors or shiny conference room tables.
Design Consideration – 2. Lighting Quality / Space & Workplace
19. Lighting Quality
Lighting on People and Objects, including:
• Modeling faces and objects
• Surface characteristics
• Points of interest
Design Consideration – 2. Lighting Quality
20. Modeling faces and objects
Lighting Quality
In human vision, shadows and highlights enhance the perception of three dimensions. Both
are the products of directional light sources. The sun and the moon produce well-defined
shadows, and are considered dramatic and attractive light sources.
Diffuse light, like the light from a cloudy sky, produces an even light that is relatively shadowfree. Once considered desirable, it is now realized that shadow-free light can fail to render
changes in surfaces making a space or task less visible. To model a surface for better
recognition of its shape and features, in general some percentage of directional light is
considered important.
Consider using a blend of direct and indirect
lighting in most designs to provide a
combination of comfort and modeling.
To achieve a minimum modeling, a directional
light for an object or area of interest should be
at least 20-25% of the total illumination.
Design Consideration – 2. Lighting Quality
21. Lighting Quality
Surface Characteristics
Lighting techniques that reveal architectural nuance like texture
enhance visual perception have become more commonly requested by
building owners and architects
Design Consideration – 2. Lighting Quality
22. Lighting Quality
Point of Interest
In retail and museum lighting, designers use highlights of up to 10 times the
ambient light level to draw attention to key display.
Recognize that it’s wasteful to create lighting than is needed.
Carefully select highlights, and use a minimum effective highlight level.
Creating highlights in contrast to lower ambient illumination levels
Creating highlights with efficient sources as close to the object or surface as
possible.
Small points of light from fiber optic sources or LEDs may offer efficient ways to
create highlights or attract attention where specifically desired.
Design Consideration – 2. Lighting Quality
24. Economics / Cost Consideration
Implementation
All of the costs and benefits associated with a lighting project should be
considered in a careful economic evaluation of a lighting system.
These include:
• Installation costs (Including equipment cost)
• Design and management costs
• Energy costs
• Maintenance costs
Advantages Of “Lighting Design Service” In Terms Of Cost Saving
Equipment Cost Control
Identifying Lowest-Cost Unit Pricing
Operations Cost Control
Avoiding Over-Lighting
Improving Reflectance and Integrating Daylight
People Costs (increased sale /productivity)
Aesthetic Costs
Design Consideration – 3.Implementation
25. Lighting Economics – An Example
Design Consideration – 3.Implementation
Implementation
26. Lighting Economics – An Example
Implementation
Simple Payback
The period of time in years required for the savings in operating or maintenance cost to
equal the additional initial investment required for the lighting system.
Design Consideration – 3.Implementation
27. Implementation
Energy Efficiency
Energy-efficient lighting design focuses on ways to improve both the quality and efficiency of
lighting.
•Match the amount and quality of light to the performed function.
•Install task lights where needed and reduce ambient light elsewhere.
•Use only energy-efficient lighting components, controls and systems. These include
Fluorescent and LED lighting options.
•Maximize the use of daylighting. Daylighting is the use of windows and skylights to bring
natural light into your home.
Use of Daylight
Energy Efficiency
Incorporate proper lighting controls
Infrared sensors
†Motion sensors
†Automatic timers
†Dimmers
…
Replacement with energy
efficient lamps
CFLs and LEDs
Design Consideration – 3.Implementation
28. End . . . . .
References
http://www.energywise.govt.nz/your-home/lighting
http://www.algonline.org/index.php?lighting-quality
ADVANCED LIGHTING GUIDELINES – 2011 edition by algonline