This project combines the architectural interest of crown molding with the soft glow of indirect lighting, whether it's along one wall or all the way around the room.
The project is no more difficult than a standard installation of crown molding—in fact, it's easier because you don't have to worry about fitting the molding tightly to the ceiling. Ripping the nailer strip is an additional step, but it's an easy task if you have a table saw. No saw? Visit a local cabinet shop and you may be able to get the strips cut for a reasonable cost. The 1-1/2-inch thickness of standard 2x lumber produces the right nailing strip height for the 4-inch crown chosen for this project. If you downsize to a 3-inch crown, cut the strips from 5/4 stock, which measures about 1 inch thick.
Paint the inside of the lighting trough to maximize light output from inexpensive rope lighting. You'll find the painting is easy because you apply it before installing the components.
Step 1: Paint and Cut
Prime and paint a white top coat on one side of the 2x6 lumber that you'll use for the nailing strips. Apply an identical finish to the back of the crown molding. Tilt your table saw blade to match the spring angle of your crown molding. For 52/38 crown, tilt the blade to 52 degrees, and make the cuts with the painted side of the board against the table. Return the blade to vertical, and slice off the angled nailing strips.
Step 2: Mark Placement
Cut a 24-inch length of the nailing strip and crown molding, then tack-nail them together to make a mock-up of the light trough. Hold the end of a length of rope light in the assembly, and position it against the wall at varying heights until you're pleased with the lighting effect. Don't place it too close the ceiling or you won't have room for the outlet box. Make a mark at the bottom of the nailing strip—4-1/2 inches from the ceiling in this case.
Step 3: Mark Level Line
At each corner of the room, make a mark at the measurement you determined, and snap chalk lines connecting the marks. Resist the urge to check whether this line is level; as long it is parallel to the ceiling, it will look fine. If you run a level line below a nonlevel ceiling, the out-of-parallel situation would draw attention to the defect.
Step 4: Screw Nailer Strips
With a stud finder and short strips of masking tape, mark the position of all wall studs. Nail or screw the nailer strips around the perimeter of the room. The white-painted edge of the strip faces upward—an easy check for proper placement. End each strip about 4 inches away from each inside corner to allow butt-fitted ends of crown molding to extend all the way to the wall.
Step 5: Install Outlet
Install a switched electrical outlet box at a convenient location. Refer to "How to Get Power to the Trough" below for ideas on getting power to the outlet. Position the box close to the edge of the nailing strip, but leave enough space to install the cover plate.
Step 6: Make Cutlines
Proceed with the installation of the crown molding, butting its backside against the strip and nailing it in place. Coped corners require a special technique so that the rope lighting can make the turn. Hold the coped piece against the piece butted against the wall, and run a pencil along the back side of the coped molding to mark a cutline.
Step 7: Corner Cut
Remove the waste from the butt-fitted piece with a fine-tooth saw and chisel. Your cut doesn't need to be pretty because it won't be seen—it's merely necessary to create clearance for rope lights. Everything else in the installation follows the usual procedures.
Step 8: Install Lights
Lay the rope lights neatly into the trough, and turn on the power to admire the effect.
How to Get Power to the Trough
You may be able to install a switched outlet near the trough from an existing wall switch.
Wire the circuit with a separate switch for the trough outlet so you can control it independently of the existing overhead light. That gives you flexibility in setting the lighting level and mood. You can either expand an existing single box to a double or purchase a double switch that fits into a single box.
Rope lights that run off a low-voltage transformer bring an additional consideration: the transformer may be too bulky to fit into the trough. If there isn't room in the trough for the transformer, find a place for it in an adjoining room or basement.