Christmas lights are a wintertime favorite. Even if you don't install your own, you probably enjoy viewing your neighbors' displays. The process can be as simple as hanging white, icicle lights from the eaves or expand to include flamboyant lawn and tree decorations.
In either case, it requires some thought and consideration to properly execute because, although outdoor lights can be beautiful when they're all lit up at night, they can also be very hazardous if proper steps are not taken during their installation.
Check the Code
The most important thing to do before you begin your project is to familiarize yourself with the building code in your area as it pertains to wiring. Also, if your neighborhood has a homeowners' association you should learn its rules regarding Christmas decorations.
Have a Plan
Before beginning an outdoor-lighting project, determine the number of lights you'll need, make a diagram of your installation, and gather the necessary tools and supplies. Nothing is more frustrating in a project like this than to have to stop in the middle of it to go to the local hardware store!
Look for the Tag
Don't cut corners on outdoor lighting. Always make sure your materials are approved by the Underwriters Laboratories (as denoted by a "UL" tag on the wiring) before proceeding. Be leery of any extension cord or wiring that comes from deep-discount stores, dollar stores, and flea markets. The UL tag could be counterfeit.
Run the Cable
Outlets for outdoor wiring should be GFIs (Ground Fault Interrupters). They come in different styles and can be either flush or wall mounted.
Always use type UF (Underground Feed) cable in any underground installation of wiring. The conductors are resistant to grease, chemicals, and being crushed.
Make sure a circuit breaker or fuse box is at the beginning of the installation. Run conduit from this box through the outside wall and then attach it to a waterproof elbow. Next, run conduit down to cable level, making a 90-degree bend at the bottom of the run from which the underground cable will extend.
Some local wiring codes require that underground cable be fully protected by conduit for the entire run to prevent digging hazard. As mentioned above, check with your local wiring code before beginning your installation.
Bury the Wiring
If you're using underground wiring, bury it at least 18 inches deep, preferably 24 inches. This puts the cable far enough down that any normal digging in the lawn will not disturb it.
Place the Outlets
Now that the cable has been run, it is time to decide where to place the waterproof electrical outlets. If you have planned properly, as outlined in step 2, you will have the cable installed and locations chosen. These waterproof outlets can do double duty, providing power for not only Christmas lighting but also other types of outdoor uses, such as post lanterns along the walkway, outdoor radios, electric trimmers, and even electric mowers.
Put Up the Lights
Now that the cable has been run and outlet boxes have been installed, you can proceed with the actual placement of your lighting project. Make sure your lights are designed for outdoor use and that each connection uses a grounded plug that fits properly into the female receptacle.
Many times outdoor lights are troublesome to connect, so if there is any doubt in your mind about the actual connection, do not use it. Remember, one leg of the plug will be larger than the other. Also, it's a good idea to wrap these connections in waterproof electrician's tape at each join.
Set Up a Timer
Many of the newer outdoor-lighting strands have photoelectric sensors in them that will turn the lights on at dark and turn off at sunrise. If your lighting arrangement does not have this feature, consider installing a timer inline with the installation at the circuit breaker / fuse box.