At Iguzzini factory, Italy

Designing the ​Perfect ​Lighting for ​Urban ​Interiors

Journal by Kanika Sanghi

Lighting is a cornerstone of interior design, influencing how a ​space looks, feels, and functions. It sets the mood, enhances ​functionality, and serves as a vital aesthetic component.

Understanding Light

Light influences how we perceive space, affecting its mood, ​functionality, and overall aesthetic. For instance, warm, soft ​lighting creates a cozy, inviting atmosphere perfect for lounges ​and dining areas, while bright, cool lighting energizes and ​enhances alertness, making it ideal for workspaces.

Lumens measure the total light output from a source, with higher ​lumens indicating a brighter light.

Lux measures the amount of light per square meter, helping ​determine the right lighting level for different tasks and spaces. ​For example, a reading area may require 300-500 lux, while ​general living areas need about 150 lux. These technical ​considerations ensure that we provide the right amount of light ​for each specific need.

Understanding the behavior of light—reflection, refraction, and ​diffusion—allows us to manipulate it effectively within a space.

• Reflection and Refraction: By strategically placing mirrors and ​using glass elements, we can reflect and refract light to ​brighten a space and create a sense of openness. For ​example, a well-placed mirror can make a small room appear ​larger by reflecting light and adding depth.
  

• Diffusion: Using materials like frosted glass or diffused light ​fixtures softens the harshness of direct light, creating a more ​comfortable and inviting ambiance. This approach is ​particularly useful in living rooms and bedrooms where a ​relaxing atmosphere is desired.
  

• Color Temperature: The color temperature of light, measured ​in Kelvin, significantly affects the mood and functionality of a ​space. Warm light (2700K-3000K) creates a cozy and ​intimate setting, ideal for lounges and dining areas, while cool ​light (5000K-6500K) enhances alertness and is perfect for ​workspaces and kitchens.
  

Technical Considerations

When designing lighting, we must consider technical aspects ​such as the IP Protection Index. The IP Protection Index indicates ​the degree of protection a fixture has against dust and water. For ​example, IP20 is suitable for indoor lighting, offering basic ​protection against dust, while IP54 is used in bathrooms and ​kitchens to protect against water splashes and humidity. For ​outdoor lighting, IP67 is ideal, providing complete protection ​against dust and temporary immersion in water, making it suitable ​for areas like pools and fountains.

Layered Lighting Approach

A layered lighting strategy addresses various needs and creates ​depth:

• Ambient Lighting: The foundation layer, providing general ​illumination with overhead fixtures like recessed lights or large ​pendants.
  
• Task Lighting: Focused lighting for specific tasks, such as desk ​lamps or under-cabinet lights in kitchens.
  
• Accent Lighting: Highlights architectural features, artwork, or ​design elements with track lighting and wall sconces.
  

• Decorative Lighting: Adds style and personality, often serving ​as a design focal point. Statement chandeliers or unique ​pendant lights fall into this category.
  

Material Considerations

The material of the products being illuminated affects how light ​interacts with them:

• Translucent Materials: Diffuse light, reducing glare and ​creating a softer look.
  
• Reflective Materials: Enhance brightness but can cause glare if ​not properly managed.
  
• Absorptive Materials: Reduce light intensity, useful for ​creating a cozy atmosphere.
  

Incorporating Natural Light

Maximizing natural light is always a priority as it not only reduces ​energy consumption but also creates a more pleasant ​environment. Large windows strategically placed to flood the ​space with daylight can transform a room. An open layout, ​minimizing partitions, allows light to travel deeper into the space, ​enhancing the overall brightness.

Reflective surfaces such as glass, mirrors, and glossy finishes are ​employed to reflect light and brighten up the interior. This ​approach is particularly effective in smaller urban spaces, where ​maximizing natural light can make the area feel more expansive ​and inviting. Natural light also enhances the colors and textures ​within a space, bringing out the best in the design elements.

Hierarchy of Lighting

Determining the hierarchy of lighting in each room is crucial. ​Identifying and highlighting the hero element can transform a ​space. In dining rooms, the dining table often serves as the focal ​point, accentuated with a statement chandelier or pendant light. ​Retail stores focus on products, using spotlights or track lighting ​to make them stand out.

Offices benefit from a balanced approach, combining bright ​ambient light with focal points like artwork or feature walls to ​create a stimulating yet comfortable environment. In hotel guest ​rooms, the bed or a unique architectural feature can become the ​focal point, highlighted by accent lighting such as bedside lamps ​or wall-mounted reading lights. This hierarchical approach ​ensures that each space is both functional and visually appealing.

Here’s a quick reference chart for color temperatures:

Here’s a quick reference chart for color temperatures:

Types of Lights

1. COB (Chip on Board)
   
• COB lights feature multiple LED chips mounted directly ​onto a substrate to form a single module. This design ​improves lumen output per square inch, offering better ​thermal performance and efficiency.
  
• Applications: High-lumen applications like streetlights, ​downlights, and high-bay lighting.
  
2. Single Chip
   
• Single-chip LEDs have a single diode emitting light. These ​are often used where precise control over light output and ​color is needed.
  
• Applications: Indicator lights, small flashlights, and ​electronic displays.
  
3. Tunable
   
• Tunable LEDs allow adjustment of color temperature and ​brightness. This feature provides dynamic lighting ​environments, adaptable to various needs throughout the ​day.
  

Applications: Smart home lighting, retail spaces, and offices.

4. Chip-Scale Package (CSP)

• CSP LEDs have no traditional package but instead, the ​chip itself is the package. This reduces size and allows for ​more compact designs with enhanced performance.
  
• Applications: Mobile devices, automotive lighting, and ​high-density applications.
  

5. Warm Dimming

• Warm dimming LEDs mimic the behavior of incandescent ​bulbs, getting warmer (more yellow/red) as they are ​dimmed. This creates a cozy and inviting atmosphere.
  
• Applications: Residential lighting, restaurants, and ​hospitality.
  

Lifespan of Light Bulbs and LEDs

• Light Bulbs: Traditional incandescent bulbs typically last ​around 1,000 hours. Halogen bulbs have a lifespan of 2,000 ​to 4,000 hours.
  
• LEDs: LEDs can last anywhere from 25,000 to 50,000 hours ​or more. Their lifespan is affected by factors like usage ​patterns and operating conditions.
  

L and B Values

L Value (Lumen Maintenance): Indicates the percentage of initial ​light output remaining after a certain period.

• For instance, L70 means the light retains 70% of its initial ​brightness after its rated lifespan.
  
• B Value (Failure Rate): Indicates the percentage of lights ​expected to fail before reaching the L value. For example, B50 ​means 50% of the lights might fail before reaching the end of ​their rated life.
  

Color Rendering Index (CRI)

• CRI: Measures how accurately a light source reveals the colors ​of objects compared to natural light. It ranges from 0 to 100, ​with higher values indicating better color rendering.
• Applications:
• Residential: High CRI (90+) for true-to-life color ​representation in living spaces.
  
• Retail: Enhances the appearance of products, making ​them more attractive to customers.
  
• Application example- All colours are rated between R1-R9. ​R9 represents red colour, so to enhance red colour in for ​example a retail project, one must look for high R9, may be ​95% and above for a true colour to come out.
  

Beam Angle: The angle at which light emanates from the source. ​Reflectors typically have a broader beam angle, while lenses can ​offer more precise control.

Field Angle: The full angle at which light is distributed to the ​edges of a space. Reflectors may provide a softer edge, while ​lenses can create sharper cut-offs.

Conclusion: Application in Interior Design

Understanding these lighting technologies and principles is ​essential for interior designers to make informed decisions that ​enhance aesthetics and functionality. For example:

• Tunable LEDs allow for adaptable environments that cater to ​various activities and moods.
  
• High CRI lighting ensures true color representation, important ​in spaces like art galleries or retail stores.
  
• Warm dimming LEDs create inviting atmospheres in ​hospitality and residential settings.
  
• Awareness of chromatic aberration helps in selecting the right ​lenses and avoiding color distortions in high-precision ​applications.
  

By leveraging this knowledge, we can create well-lit, comfortable, ​and visually appealing spaces that meet the specific needs of our ​clients.