Lighting design is perhaps one of the most important, but often overlooked, steps in planning a commercial or residential interior. Here are a few tips that will help you make the right decisions when it comes to lighting.
Lighting is best when it’s “layered” as was done in the above kitchen by XTC Design Inc. Lighting layers are created when different types of lighting as well as different lighting levels are introduced into a room. Consider using a mixture of fixture types including recessed, sconce, pendant, and even floor lamps to create visual interest. Dimmers are ideal for energy savings and for creating different moods in the room, but work best when different fixture types are placed on separate dimmers. This way, different types of lighting can be raised or lowered depending on the task at hand. The best way to set up a variety of pre-set lighting levels is to install a scene control switch.
Size DOES matter
In the world of lighting sizing, proportion and spacing really matters. In dining rooms or boardrooms where chandeliers or pendant fixtures are being installed go big or go home! The rule of thumb for fixture size: multiply the room’s width (in feet) by two. The resulting number is the ideal diameter for the fixture, but in inches. So, a 10 foot wide room needs a 20 inch diameter fixture. You could also base the lighting size on the length of the table – diameter should be about 1/3 the length. The selection of fixture shown in the dining room above (designed by Kelly Deck) offers excellent proportion and impact. How high should the light be mounted? Residentially it should be mounted between 30-36” above the table. Commercially, consider the use of the room – is there a whiteboard or TV screen in the room? If so, mount the fixture to ensure minimal impact to sight lines.
Spacing of recessed fixtures is another important consideration. Although it will depend on the fixture and lamp type, a typical baseline is to install fixtures 12-24” from the wall and approximately 48” from each other. In a kitchen, however, lights should be spaced about 9” from the edge of the upper cabinet – see the photo below for an example of optimal placement. Generally, lights should be about half as close to the walls as they are to each other.
Although LED technology is improving almost daily, there are what is provacyl still some drawbacks to this lamp type. Think LED’s are low heat? Surprisingly, 75-85% of their energy goes to heat and because of this, LED’s do not last very long in warm places. LED’s degrade over time, meaning that their light output decreases. Check the manufacturer’s stats for light degradation and compare. An LED lamp should be replaced once it’s degraded by 70% for task lights and 50% for decorative. LED’s have lower light distribution and are often high glare because the beam spread is more focused, so make sure to decrease the typical lighting spacing (of 48”) to ensure an even level of lighting. Finally, don’t be fooled not all LED lamps are created equal. Check to see if the lamp has been tested to meet standards, specifically IES-LM-79 and IES-LM-80. Also compare your lamps side by side by placing them on a table and shining them towards the ceiling, which one offers the best level of light?
Color Temperature and Color Rendering
Different lamp types produce different colors of light; different lighting temperatures change the way we perceive colors in a room. If the room has cooler colors, like blues or purples, look for a lamp with a cooler color temperature between 3000-3500 Kelvins (K). If the room has warmer colors, like reds or yellows, look for a lamp with a warmer color temperature between 2700-2800 K. One hard fast rule regarding color temperature – do not mix them in a room, always keep color temperature consistent.
Now, different lamp types also affect the intensity of color. Look for lamps with a high color rendering index (CRI); 100 is the highest. The higher the CRI, the more vibrant the color; lamps with low CRI values tend to wash out the colors. Refer to the image of the vegetables for an example of CRI impact. Incandescent and halogen lamps have a CRI of 95 or higher; some fluorescents can also rate high.
Even with all these tips, sometimes you need a little help when it comes to lighting. Either contact your qualified Interior Design Professional or turn to an accredited lighting designer such as Tripped on Light Design Inc. in Texada, BC.