Recessed lighting layout and spacing

Recessed lights look simple, and that is why a poor layout stands out: dark corners, bright circles on the walls, a shadow exactly where you chop vegetables. Most of the work happens before any hole is cut. This is how I think about a layout.

Start with what the room is for

Decide what each part of the room needs before you count fixtures.

• General light fills the room evenly so you can move around.
• Task light goes over a counter, a desk or a reading chair.
• Accent light washes a wall or points at a fireplace or a painting.

A kitchen needs strong task light over the counters. A living room usually wants softer general light on a dimmer. A hallway needs only enough to walk safely.

A rule of thumb for spacing

A common starting point is to space the lights about half the ceiling height apart. With an 8-foot ceiling, that means roughly 4 feet between fixtures. Higher ceilings allow more distance, because the light spreads wider before it reaches the floor.

It is a starting point and not a law. The beam angle of the fixture, its brightness and the color of the walls and floor all change the result. Dark rooms need more light than white ones.

Distance from the walls

Lights placed too close to a wall draw bright arcs on it. Lights too far from the wall leave the edges of the room dim and make it feel smaller. A usual choice is to put the first row at about half the spacing between fixtures. If the lights are 4 feet apart, the first row sits about 2 feet from the wall.

Over a kitchen counter the rule is different. Line the lights up over the front edge of the counter and not over the middle of the floor. Otherwise you stand between the light and your work and cast a shadow on it.

What is above the ceiling

The plan on paper has to survive what is inside the ceiling.

• Joists. A fixture cannot sit where a joist runs, so the grid often shifts a few inches. Keeping the rows straight matters more to the eye than exact spacing.
• Insulation. A fixture that touches insulation must be rated for insulation contact, marked IC. This is common under an attic or a roof.
• Pipes, ducts and wires. They are found only when someone looks, which is one reason to plan before cutting.
• Sloped ceilings. They need fixtures made for a slope or with an adjustable head, so the light points down and not across the room.

Slim LED fixtures need far less space than traditional cans and fit in many ceilings where a can would not.

Brightness, color and dimming

• Color temperature is measured in kelvins. Around 2700K is a warm light, like an old incandescent bulb. 3000K is slightly whiter. 4000K and above is cool and suits a work area better than a bedroom. Keep the same color in every fixture you can see at once.
• Dimmers make recessed lighting much more useful, but not every dimmer works with every LED. A bad match shows up as flicker, buzzing or lights that never fully turn off. The fixture’s maker usually lists the dimmers it has been tested with.
• Wet areas. A light inside a shower or over a tub must be rated for that location.

What you can safely check yourself

• Measure the room and the ceiling height and sketch the layout on paper.
• Mark the positions on the ceiling with painter’s tape and look at them from the doorway and from where you sit.
• Find the direction of the joists with a stud finder, or from the attic if you have access.
• Decide on a color temperature by looking at a sample at night, in the room.
• Take photos of the ceiling, of the switches and of the attic above.

When to stop and call an electrician

• Before cutting into a ceiling when you do not know what is above it.
• When there is insulation over the ceiling and you are not sure the fixtures are rated for it.
• For any new wiring, a new switch or a dimmer. Adding lights to an existing circuit also means checking that the circuit can carry them.
• If existing recessed lights flicker, shut themselves off after a while or show brown marks around the trim. A fixture that turns itself off is overheating.

Send me the room’s measurements and a few photos and I will suggest a layout along with the estimate. See recessed lighting or ask for a free quote.