Diffused LED tape light install.

Two of my nieces asked for LED tape lights for their birthday last year. I've been reading horror stories of the tape lights peeling off the walls after a few months and the harshness of looking right at the LED light. The frosted diffusing channels were going to kick the project cost up too much. I've seen some nice crown molding installation options, but kind of overkill for some kids rooms. But quarter round or shoe molding installed upside down as a ledge for redirecting the light.. quite affordable.

Took me one day of labor per room, but the nieces love the result.

Supplies

Quarter round or shoe molding
Finishing or brad nails
Brad finisher and hammer
(Optional) Soldering iron and accessories
Extra wire and clips
Tape LEDs, 30 to 60 feet to transverse perimeter of the room
Miter box and flush cut saw
Pencil
Tape measure
(Optional) Laser range finder
Level (longer is better)
Stud finder
(Optional) Star/Galaxy projector

Step 1: Cut Molding to Length

Measure the 4 walls of the room (parallel walls should, but sometimes don't have equal lengths). Purchase quarter round or shoe molding... buy four pieces to the room's wall length plus about six inches (some leeway for mistakes). (You could get in smaller pieces and line up/reconnect on the wall; but borrowing a truck or strapping them to the room will result in a cleaner look in the end.)

Cut 45 degree angle on one end of the molding.

Double check length/fit on the wall, and than cut a 45 degree angle on other end of molding... making sure a ledge is on top (round part on bottom). Also make sure you flip the angle.

Step 2: Mark Studs, Predrill Molding, and Hang

Using the stud finder determine location of studs on the four walls (approx every 16"), and mark them either with a pencil or some tape. I find magnets helpful as well, rub them over the wall until they stick to the drywall screws; revealing/validating the location of a stud.

Line up the molding to do a test fit, and place pencil marks on the molding to line up with the stud locations.

Remove the marked up molding. Predrill from the back of the molding near the pencil marks (this makes driving the finishing nails much easier; unless you have a powered finishing/nail gun).

After predrilling, line the molding back up into place on the wall, about 4" from the ceiling, and install brad or finishing nails through the predrilled holes into the stud. Repeat for adjoining wall, trying to line the 45 degree corners up. Use the brad finisher to hammer the nails in below the surface of the molding.

Step 3: Apply Tape Light, and Corner Connections

After the four walls have the molding/ledge created you can start applying the LED lights.... start near where you will be plugging in the power (AC cord). Due to maximum lengths of each run, you should run two different rolls of LEDs starting from that same point; to fully circle the room. You can either use the LED's tape to secure to the top of the molding (with the ledge support, the tape won't fail) or can secure with specialized mounting tabs.

When getting to corners, there is a technique for folding/looping the LEDs to make a 90 degree turn/bend... but that leaves a visible loop. Alternatives are to use "L" connectors, but would require the cut point lengths to be in your favor (unlikely). There are only specific points where you are permitted to cut the LED tape to size. Instead of the "L" connectors you can either solder the lengths with wires to bridge out the gap; or use special solderless connectors with or without wires preattached. I took this route, using the solderless connectors. If you're using waterproof tape lights, you will need to peel away some of the silicon so the connector can work properly. This method will make for cleaner corners.

Step 4: Finished

The finished look is clean, and provides a diffused light bouncing off the ceiling. And the lights will not peel off on their own. Four months and counting so far.

The nieces are very pleased with the end result. They've mentioned their friends are jealous; some of them have had the tape lights installed only to have they peel away and fall of the walls.