Step 1: Mark the wall
Draw reference lines to indicate the bottom of the light strip and the bottom of the base. Don’t worry whether the lines are level. Instead, measure down from the ceiling in several places and connect the dots to achieve a consistent distance between the cove and the ceiling. Years of settling can throw a ceiling out of level. A cove not in line with the ceiling will create a noticeably uneven gap. Save time by cutting a couple blocks of wood to use as marking gauges before installing LED strip lights.
Is cove lighting right for you?
You may think your ceiling looks good now, but when the cove lighting rakes across the surface, you may discover seams and nail pops you never knew existed. Stand on a ladder and shine a flashlight across the surface of the ceiling. If your ceiling is super ugly, you may want to abandon the idea or build a cove that washes the walls with light instead.
Our cove lighting design
Our cove is built from crown molding and set 2 in. down from the ceiling. We installed the crown on top of a baseboard to create a wider space for the light, and tacked a small cove molding onto the bottom of the base to finish it (Figure A). We fastened a LED light strip to the wall so the lights would rake across the ceiling, and in order to maximize the light, we kept the strip as high as we could without its being visible from the ground.
Make a small mock-up and experiment with different positions for the cove and lights. Every room is different, and the cove we made may not be the best style for your room.
It’s easier to paint all the cove parts before you install them. Touching up a few nail holes after installation is a lot easier than taping off entire walls. Painting the part of the wall that will be seen above the cove will help tie everything together. Choose either the color of the ceiling or the color of the cove. Lighter colors reflect more light, so paint the back of the cove components as well.
Step 2: Install LED strip lights
Photo 1: Installing LED Strip Lights First
If you plan to attach the lights to the wall, it’s easier to install the lights before you build the cove.
When you’re placing the LED strip on the wall rather than inside the cove, it’s easier to install most of it before the cove is up. Begin at the point of the room where the transformer will be installed. Leave the tape backer on the first few feet of the LED strip so it can be pulled away from the wall when it comes time to connect it to the transformer.
The tape on the back of the strip is super sticky. Once it’s on the wall, it’s tough to remove without pulling off the paint along with it. To start, press the strip to the wall in one spot, hold it there, pull the tape out a couple feet, and press it to the wall at that point as well (Photo 1). Do this a few times in a row, and check to see if it’s straight. If it is, go back and press the rest of the tape tight to the wall. Strip lights like these can be cut to size but only in certain intervals, usually 2 to 4 in. There will be clearly marked cutting lines on the strip.
Other Lighting Options
LED lighting isn’t cheap. A system like we installed costs $9 to $14 per ft. for 22 ft., but less expensive options are available:
Step 3: Build the cove
Photo 2: Fasten the base
Drive 2-in. screws through the base into each stud. Sink the screws flush and place them high enough to be covered by the crown molding.
Photo 3: Attach the support blocks
Cut blocks to support the crown molding. Fasten them into place with 2-in. 18-gauge brads. Mark them so you don’t confuse which way is up.
Secure the base to the wall with 2-in. screws into every stud (Photo 2). Self-tapping trim-head screws work great. Keep the screws high enough so they get covered by the crown. Depending on the size of the transformer, you may need to notch out a section of the base to make room so it’s not visible from the floor (Figure B).
Cut blocks to support the crown. One easy way to figure out the angle for the blocks is to hold a section of crown next to your table saw blade and adjust the blade to the same angle as the crown. Rip a 2×4 at that angle. Before installing the blocks, indicate with a marker which way is up. Stagger the blocks about every 16 in. or so, and fasten them with 2-in. 18-gauge brads (Photo 3).
Working with cove molding can be tricky, and in this article, we don’t cover all the techniques for measuring, cutting and coping. For more information, read How to Install Crown Molding or go to the DIY University and take a course on crown molding.
Finish up by installing the small cove at the bottom. Fasten the cove with 1-1/4-in. brads angled up into the base (Figure A).
Step 4: Fish the new cables
Photo 4: Cut out the existing outlet box
Pull the power for the lights from an existing box on an interior wall. Cut out the nails and remove the existing box. Replace it with a larger box to make room for the new wires. Removing the existing box will also simplify fishing in the new cables.
Photo 5: Fish the cable
Cut a hole in the wall for the switch box, and run a cable down through the outlet box hole below it.
Photo 6: Install the new boxes
Pull back the sheathing, strip the end of the wires, and pull wires into the remodel boxes before inserting them in the holes and clamping to the drywall.
Pick an existing outlet on an interior wall to pull power from so you don’t have to deal with insulation when you fish the new cables. There’s a good chance the existing electrical box may not be big enough for additional wires, so plan to replace it with a larger 20-cu.-in. remodel box (sometimes called an ‘old work’ box). Removing the existing box also makes it easier to fish in the new cables. Shut off the power, then poke a hacksaw blade on either side of the existing box to find which side the stud is on, and cut out the nails that hold it in place (Photo 4). If this kind of electrical work is intimidating, you could learn all you need to know by taking a few electrical courses in The Family Handyman’s DIY University.
Use the remodel box as a template to cut a hole in the wall for the new light switch. There’s no need to cut the hole next to the stud. Remodel boxes are held in place with wings that clamp onto the back of the drywall. Cut the hole for the switch box with a jab saw or utility knife at the same height as the other switches in the room. Fish the new cable from the switch box hole down and out through the existing hole below it (Photo 5). Put a slight bend on the cable so it hugs the back of the drywall, which makes it more easily accessible.
In this article, we used a transformer that is hardwired, so an outlet box wasn’t necessary. We just had to drill a 3/4-in. hole in the drywall above the cove and run a cable down to the switch (Figure B). There are other lighting options that may require an outlet above the cove. The procedure is the same as the next step; just be careful to place the new outlet so it’s completely hidden behind the cove. It will also help to install a recessed outlet box for the light’s power cords.
Whether you install an outlet, leave a few feet of cable sticking out of the wall at the top. That will make it easier to wire the transformer. The excess cable can be pushed back into the wall cavity after the connections have been made.
Be generous and remove 10 in. of the cable’s sheathing and strip the end of each wire before pulling them into the box. Make sure there’s at least 1/4 in. of sheathing extending into the box and 3 in. of wire length extending beyond the face of the box (Photo 6). Don’t over-tighten the box onto the drywall or you could strip the screws or damage the portion of the drywall that holds it in place.
Design Your Own
You don’t have to build your cove exactly the way we did. Here are a couple alternative styles:
Step 5: Complete the connections
Photo 7: Connect the transformer
Leave extra cable up top so the transformer can be pulled away from the cove to be wired. The excess cable can be pushed down into the wall cavity. Notch out the base so the transformer can sit lower in the cove.
The existing receptacle will need to be replaced with one that is both tamper resistant (TR) and protected with an AFCI (arc fault circuit interrupter). AFCI interrupters protect homes from fire and are now required in most locations of the home. The AFCI has ‘line’ and ‘load’ terminals and cannot be connected with ‘pigtail’ wires like the existing outlet may have been (Figure B).
It’s extremely important for the dimmer switch to be compatible with the LED light strip you install. You need a ‘low-voltage’ compatible switch, not an ‘LED’ compatible switch. The wrong switch will cause the lights to flicker or not work at all. We used a Lutron switch recommended by the lighting supplier.
Transformers come in many shapes and sizes. Follow the wiring directions on your particular transformer. Once the transformer is connected, slide the excess cable back into the wall cavity and finish securing the strip light (Photo 7). Stick the transformer to the wall with Velcro strips if it won’t stay in place, and install cable straps with drywall anchors.
Step 6: Install the crown
Photo 8: Install the crown
Tack the bottom of the crown to the base with 1-1/4-in. brads and to the blocks with 2-in. brads.
Fasten the bottom of the crown to the base every 16 in. with 1-1/4-in. 18-gauge brads. Secure the center of the crown to the blocks with 2-in. brads (Photo 8). To avoid nailing through the tops of the blocks, aim the gun straight in toward the wall rather than angling it up toward the ceiling. You don’t want to poke yourself on an exposed brad or damage the light strip with a wayward shot.
All that’s left is to flip the power back on and plan that dinner party so you can show off to all your friends.
Choosing LED Lighting
It’s very important to think of low-voltage LED lighting as a ‘system.’ Transformers are available in 12-volt, 24-volt, magnetic, nonmagnetic, dimmable and nondimmable. The transformer, strip lighting and dimmer switch all need to be compatible.
You’ll also have to consider how much lighting you need. Two transformers may be required for large rooms because each transformer can only provide power for a specified length of strip lighting. The lights at the end of a long run will be dimmer than the others if hooked up to an undersized transformer. White light is most often used in commercial settings or outdoors, while warmer colors are preferred for homes. Brighter (more lumens) strip lighting costs more but is a good option. Strip lighting that is run at less than full power will last longer. Some lighting systems can last up to 50,000 hours.
Your best bet is to stop in at a lighting store, or call an online retailer, and explain the dimensions and layout of your room exactly. We bought our lighting from LED WORLD at ledworldlighting.com. The staff were extremely helpful in presenting our options and making sure we had all the proper components to finish our project.
Required Tools for this Project
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
- 18-gauge brad nailer
- Drill/driver - cordless
- Miter saw
- Table saw