Lighting Design

Introduction

Properly lighting a home provides a unique challenge. It must be both effective and visually pleasing in a large variety of situations and purposes. As the ultimate multi-use environment, home lighting requires thoughtful planning and design. Lighting is able to add drama and beauty to rooms, while making smaller rooms appear more open and airy, and larger rooms feel cozy and inviting. Lighting in a home can drastically change the mood and allow homeowners to enjoy their home to its full potential.

This equally applies to commercial settings. Whether it’s a vibrant, well-lit office space or an intimate, cozy restaurant atmosphere, our products cater to diverse lighting needs, creating lasting impressions and visual experiences.

Understanding light obtained by LED 

LED luminaries are highly durable and efficient, outlasting fluorescent and incandescent bulbs while maintaining superior light quality with a higher Color Rendering Index and minimal flicker. LED luminaries generate less heat, reducing the risk of fire. 

LED lighting is utilized to:

1. Create a warm and inviting environment, while making it functional and safe.
2. Integrate and balance ambient, task, and accent lighting into every room to allow for a variety of settings and moods.
3. Establish a path of illumination through the house to allow for comfortable transitions from room to room.
4. Enhance and strengthen the character of the living space by highlighting areas of interest and architectural details.
5. Design a flexible lighting scheme to take you from dawn to dusk and a system that is easy to maintain.
6. Address energy efficiency concerns and code issues.

When lighting a residential space, consider the following characteristics:

1. Size and shape of the space.
2. Traffic patterns through the home.
3. How the room will be used: what tasks will be done in each space and how much light these tasks require.
4. The ceiling height and shape: how light will be reflected off these surfaces and contribute to the ambient light level in the room.
5. Age of the persons living in the space: the older we get, the more we are adversely affected by glare.
6. Color of the walls: darker walls absorb more light and may require higher levels of illumination.
7. Artwork and highlight areas: knowing which pieces and areas are to be highlighted helps determine the number of accent lights required.
8. The families of luminaries: recessed down lights used as adjustable accents and wall washers should match surrounding lights. They should have similar aperture size and trim finish, as well as use matching lamp types. Complementing choices of lights avoids drawing attention to the lighting system.

Lighting Layers

Lighting layers aid designers in determining the specific lighting needs of a room, facilitating the creation of desired moods or atmospheres. Combining and balancing these layers adds visual interest and enhances the attractiveness, excitement, and inviting nature of the space. The four typical layers of residential lighting include general (or ambient) lighting, task lighting, accent lighting, and decorative lighting. 

General (Ambient) Lighting

General (ambient) lighting serves as the primary illumination source in a space, offering uniform brightness for orientation and tasks. Ambient lighting should radiate a comfortable level of brightness and provide a sense of relaxation and spaciousness. Achieving this involves arranging recessed fixtures using reflectors, baffles, and lensed trims in overlapping positions. Perimeter lighting, or wall washing, helps define spaces, provides vertical lighting, and makes the space feel larger. Done with sconces or wall washers, vertical lighting creates a pleasant, welcoming environment and adds to the visibility and visual impact of the space. Vertical surfaces should be illuminated to for visual comfort, spaciousness, and provide visual and directional cues. 

Task Lighting

Task lighting illuminates specific areas for focused tasks, offering localized and higher levels of illumination. Necessary to the functioning of a space, it is important to use energy efficient sources to reduce operating costs. Task lighting is most effective when used as a supplement to general lighting in workspaces, conference areas and on counter tops. 

Effective task lighting should eliminate shadows on the specific illuminated area, while preventing glare from the lamp itself or off surfaces. Although ambient light should still provide the majority of illumination, task lighting reduces the reliance on overhead lighting, and provides a better quality of light for specific tasks.

Recommended light levels for task areas are 50 – 200 foot candles. When lighting a task area, consider the contrast between the task space and its surroundings. A 3:1 ratio of task lighting to general illumination offers suitable contrast. The amount of light needed on the task, or luminance, is usually the most flexible variable of task lighting, and can be increased to compensate for low contrast levels. 

Accent Lighting

Accent lighting reinforces design aesthetics by highlighting shapes, textures, finishes, and colors, creating visual interest and enhancing various elements in a space. It adds depth, contrast, and serves as a focal point, accentuating shape, texture, finish, and color. However, ambiguously directed accent lighting can result in unwanted shadows, obstructing highlighted item details, or causing distracting glare.

Effective accent lighting involves more precise and of higher intensity than the surrounding ambient light. Track fixtures, recessed housings with adjustable trims, and concealed adjustable illumination with point source lamps offer directional control, ideal for accent lighting. This technique allows precise aiming to highlight product attributes and influence customer impressions.

Accenting everything and emphasizing nothing is a common mistake with accent lighting. It's crucial to find the right balance and avoid excessive brightness.  The IESNA recommends a 5:1 ratio of accent light to ambient light to make objects stand out and create a significant visual effect. Dark merchandise may require a higher ratio to bring out details.

Recommended light levels for accent lighting are between 150 – 500 foot candles. For feature displays, higher ratios of 15:1 or 30:1 are used, especially to create sparkles in jewelry or crystal.

Decorative Lighting

Decorative lighting serves a dual purpose: not only to contribute to the lighting layers in a retail environment, but also to enhance the look of the space as a design element. Decorative lighting includes pendants, sconces, chandeliers, table and floor lamps, and cylinders. Decorative lighting should complement and add visual interest to the interior, as well as provide or contribute to the overall lighting plan.

Pendants should be mounted 6 – 8 feet above the finished floor (a.f.f.) so they are still within view, but not too low as to deter visual communication. Wall sconces and wall mounted cylinders should be mounted approximately 5-1/2 feet a.f.f.; this helps to create a sense of human scale. Adding décor, beauty and style using decorative lighting is also an important reflection of a store’s brand image, and reinforces the theme and style of the space. It fosters a sense of hospitality and comfort, encouraging longer visits and potentially increasing sales. Layering various lighting types makes the store more attractive, exciting, and inviting.

Determine the Room Square Footage

Multiply the length of the room by the width of the room to get the Room Square Footage.

Determine the Foot Candles required for a Room

A Foot-candle is how bright the light is one foot away from the source. Lighting requirements need to vary depending on the type of room being lit. For example, a bathroom or a kitchen will require more foot-candles than a living room or bedroom.

Here are some examples of needed foot candles :

Rooms

Living Room : 10-20
Hallways : 5-7-10
Kitchen General : 20-30-50
Kitchen Stove : 20-50
Kitchen Sink : 20-50
Dining Room : 10-15-20
Bedroom : 5-10-20
Bathroom : 20-50
Writing / reading : 40-80

Offices

Accounting : 50-100
Audio-visual areas : 20-50
Conference areas : 20-70
Corridors, stairways : 20
Drafting : 50-200
Private offices : 50-100
Lobbies, lounges & Reception areas : 0-20

Determine the required Lumens

Lumen is a unit of measurement of light. A lumen is a way of measuring how much light gets to what you want to illuminate. To determine the required lumens, you will need to multiply your room square footage by your room foot-candle requirement. For example, a 100 square foot living room, which needs 10-20 foot-candles, will need approximately 1,000-2,000 lumens. A 100 square foot dining room, which needs 30-40 foot-candles, will need approximately 3,000-4,000 lumens.

How to Calculate Lighting to get a quick idea of fixture foot print : Kitchen Example

Let’s do a lighting calculation for a 10 by 12 foot kitchen as an example. For our basic general kitchen lighting, we know from the table above that we’ll need 20-50 foot candles. For food preparation, we’ll want closer to 50 to 100* foot candles. Start by calculating the area of the kitchen. By multiplying the length and width of our kitchen together we get 10 feet X 12 feet = 120 square feet.

Now to calculate the required lumens for the kitchen we multiply the number of foot candles (let’s take the dimmest general lighting level of 20 foot candles first) by the square footage. For this we’ll need 2400 lumens.

20 foot candles X 120 square feet = 2400 lumens

For the maximum foot prep level of 100 foot candles, the calculation would be:

100 foot candles X 120 square feet = 12,000 lumens

For compact fluorescent lights (CFL) the illuminance tends to be about 40 to 70 lumens per Watt of power draw (incandescent lights are closer to 10-17 lumens/Watt). For our example let’s use 20 Watts CFLs rated at 1200 lumens.

So for our lowest light requirement of 2400 lumens, the calculation would be:

2400 lumens / 1200 lumens per bulb = 2 bulbs

For our brightest light requirement of 12,000 lumens, the calculation would be:

12,000 lumens / 1200 lumens per bulb = 10 bulbs

That seems like a lot of lights but if you consider all the light possibilities for a kitchen: dimmable recessed lights, under cabinet lights, stove top vent hood light, and a few tracks or hanging lights right above an island or prep counter, you could reach that ten bulbs level easily.

For some however, this level of 12,000 lumens may simply be too bright. For a more personalized home lighting design, do a few quick calculations in your current home to determine the light level in a given room. Compare the light level of that room to the tasks shown in the table above. If you feel the light in that room is inadequate, bring in a few extra lamps from other rooms until the light seems right. Add up the number of lumens from all the bulbs in the room and then calculate the number of foot candles you now have in that room. Compare this number to the chart above to get a feel where in each range you prefer your lighting.

To achieve the variation in light level required between the general kitchen lighting level and the food prep lighting level, you can group your lights on a few different switches. Under-cabinet lights are often on a separate switch, as are the lights in the stovetop vent hood. You can also have any fixtures directly over an island or peninsula style counter on their own switch.

Documents Required for a Lighting Design Quote

The following documents are necessary for an effective lighting design plan and accurate scope:

• CAD files with dimensions or a PDF with dimensions.
• Room heights measured at floor finish.
• Furniture layout plan.
• Details of wall finishes (e.g., paint, wood, brick, metal, glass).
• Colors of all finishes.
• List of planned lighting fixtures by the designer or architect.