Recessed lighting spacing - How many recessed can lights do I need? How far apart do I place my can lights?
I've been an interior designer for over 16 years now and I've realize good lighting placement is key for any space, especially so for recessed lighting - (we call them pot lights in Canada - no - not those sort of lights!). I've written this handy post to show you how it's done!
(We'll talk about bathroom lighting in another post!).
Note: Lumens measure the total light sent out by the light bulb.
Watts measure the amount of power used by the bulb.
So watts do not tell you how bright the bulb is - but Lumens do.
However, since we are all use to discussing wattage, often people use 'wattage' as their term denoting the brightness of a bulb, rather than 'lumens'. For this article we'll use the term "wattage" as most people are more familiar with that term.
Recessed can lighting design layout:
Part A: How many pot / recessed / can lights do I need?
Formula: total sq. footage x 1.5 = total wattage needed. Total wattage divided by 60 watts (or whichever wattage you select) = total amount of recessed can lights.
Example: 240 square foot room x 1.5 = 360 divided by 60 (the bulb wattage I'd like to use) = 6 recessed lights needed.
Part B: Draw up a ceiling diagram (reflected ceiling plan) showing the amount of can lights you need (Part A formula). The cans / pots / recessed lights should be evenly distributed around the room, usually they are in rows with an equal number of cans in each row. Here's a great example of a kitchen lighting layout, the yellow dots show the recessed lights, the red dots show the pendant lights:
Now we will calculate the spacing between each recessed light.
Part C: Light spacing in a row:
Part D: Task Lighting Layout:
Task lighting is extra lighting used to highlight spaces where you need either extra light, or specialized lighting throughout the home. You may want to add under cabinet lighting, or pendant lights over the island in the kitchen, to bring the lighting closer to the work area.
How to calculate the distance and spacing for task lighting:
Step 1: Determine the distance from the ceiling down to the surface you wish to light, i.e.. the floor or a countertop.
Step 2: Divide this distance by 4 to obtain the distance from the wall to the first light unit. I.e.. 8' ceiling lights should be placed two feet away from the wall.
Part E: Wall washers recessed lighting layout: (lighting that shines down onto a wall in order to highlight art or a wall feature)
Step 1: The rule for installing wall wash recessed fixtures is approx. 1.5' to 3' away from the wall.
Step 2: Fixed lights can be placed closer to the wall.
Step 3: Place adjustable lights farther away from the wall. The optimal aiming angle to minimize glare is 30-degrees from the ceiling, that way we avoid glare.
Step 4: Space wall wash fixtures the same distance from each other.
Step 5: A good rule of thumb is that your accent lighting should be 3 times brighter than the ambient light in the room. This is useful for living rooms, hallways and dens/offices.
Part F: Beam Spread
There are generally 2 types of recessed lights - Spot lights and Flood lights.
Spot lights have a narrow beam of light casting light to a focused area, usually these are used to highlighting art or important design elements in the room. They cast beams 45 degrees or less.
Flood lights case a wider beam on the floor area and are used for lighting larger, more general areas. They cast beams up to 120 degrees.
Lighting Beam calculation: Angle of beam x 0.18 x ceiling height = Beam spread in inches.
Example: 60 degrees x 0.18 x 10' ceiling height = 108" divided by 12 = 9' wide beam spread.
To create overlapping beams of light for ambience, make sure that your beam spread diameter is equal to or greater than the distance between light sources fixtures.
Recessed lighting design & installation:
Now that the recessed lighting placement locations are determined, we need to find out if they can be installed in these locations. Use a stud finder to determine where the ceiling joist are located. You might have to adjust placement locations to avoid hitting a ceiling joist. It's always best to pre plan the lighting design before your renovation or new build in your home.
Please remember to contact your electrician before making any electrical decisions.
You also may enjoy this other article:
15 Steps to Build your Dream Home
Jil Sonia McDonald - Interior Designer of Jil Sonia Interior Designs.