Overview
Recessed lighting is a great choice for lighting your home. It's relatively inexpensive and will stand the test of time, looking just as good five years later as it did the day you installed it. To keep costs down and ensure your design lasts for years, you'll simply need to figure out how many recessed lights should be in a room.
Choose and Test Your Recessed Lighting
Before you can figure out how many recessed lights should be in a room, pick which type of light pot you'll use. The size and design of your lights will affect how many you need. Choose your favorite design, and buy just one. Once you get it home, test it in the room you'll use it in to find out how far it spreads light. The general rule is that 4-inch lights should be placed 4 feet apart, 5-inch lights should be placed 5 feet apart, and so on. But test your lights first, because the height of your ceilings could change that. High ceilings may mean you need more lights.
Light Placement
You don't want your room to look like a runway, so avoid long rows of light down the center or sides of a room. If you're figuring out how many recessed lights should be in a task-oriented room, like the kitchen or bathroom, be careful. You don't want lights to be directly overhead of where tasks will be performed, or else your head and shoulders could block the light coming down. If your aim is to light a piece of artwork, other object or architecture, center the light with whatever you're lighting and make sure it's about 12 inches away. If the object you're lighting is large, like a fireplace, use two or three lights from different directions.
Which Room?
When figuring out how many recessed lights should be in a room, it's also important to consider the room's use. You want bright lights in the kitchen and bath because of the many tasks performed there. But living rooms and family rooms usually rely more on lamps, so you won't need as much overhead lighting.
Design Your Recessed Lighting
Now that you know what you need to take into account, it's time to figure out exactly how many recessed lights should be in a room. Pick your room and start at a wall. You'll only need lights against a wall if there is seating there, as in a living room, or it's a task area, like a counter top. Go across the room slowly, taking into account all the task areas, any artwork or objects you want to illuminate, and lighting you'll need to enhance light from lamps. Use your previous calculations to figure out how many recessed lights should be in a room.
Design Example
Assume you're lighting a small eat-in kitchen with low ceilings. You test one of the lights you want and find that you'll need to space the lights every four feet to provide the bright task lighting you want in a kitchen. That means you'll divide everything by four to figure out how many recessed lights should be in the room. You start at a 12-foot wall that includes the sink, stove and counter space. This whole section will need to be lit brightly because of its use, so 12 feet divided by four is three lights. Working backward, there's also counter space on the wall to the left, and windows on the wall to the right. The counters on the left extend back 6 feet. So to properly light that counter top, you'll need seven divided by four, or one more light. Really, it's more than one, but remember that the last light above the other counter top will light part of this counter, too, because it's a corner. Next, take into account eating areas and items you want to light. In this example, we'll say there's a table and a hutch. You decide you'll need to light up 8 feet to cover the eating area (eight divided by four is two lights) and 4 feet for the hutch (four divided by four is one light) for a total of three more lights. But you want to light the hutch from two directions, so you add in another light. You'd need a total of eight lights for this small kitchen.
Tips and Tricks
If your ceiling is concrete or has intricate plaster work or architecture, recessed lighting isn't a good choice and you should pick a different kind of lighting.
If you're installing lights in a new room, you'll use different lights than if you're retrofitting a room already in place. Be careful to choose the proper lights for the job.
If you're retrofitting lights and there is insulation in the ceiling, you'll need to install special light housings that are safe for insulation contact.
In the kitchen, try installing lights below the kitchen cabinets instead of in the ceiling. This gives you direct, focused light on your counter-top task areas.
You can make a room appear larger by aiming recessing lighting toward the walls around a small room.
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