FAQ: What do I use to outline my roof?

FAQ: What do I use to outline my roof?

During Christmas, a few basic materials are used to outline rooflines with lights. The list includes C7 or C9 Christmas cords, bulbs, commercial clips, and gilbert plugs (both end and inline). You'll also need wire snips and traditional or liquid electrical tape.

1. Christmas Light Cord

This is a traditional cord that is constructed with stranded 18 AWG wire (also known as lampcord) that is rated for 10 amps with sockets spaced regularly along the line. These are the C7 or C9 light strings you might have been reading about.

C7 or C9 refers to the size of the bulbs. They have different-sized bases and use cords with different sizes of sockets.

C7 and C9 Christmas light cords are all listed starting at this category.



2. Christmas Bulbs

Search for your favorite bulb(s) at our bulbs page.

Choices to make regarding bulb choice include:

  1. C7 vs C9 (or possibly round! G30, G40, or G50 are also great choices for Christmas)
  2. Glass vs. LED
  3. Smooth, Faceted, Opaque, Twinkle
  4. Color!

3. Clips

After choosing a favorite bulb and cord combination, the right clip to use for installation is the next choice. Choose clips based on how the roofline is configured.

Many clips are designed to work by either sliding under the edge of the roof shingle or can be flipped to install the light sockets on a gutter.

Scan down this page of Christmas clips to choose the best match for your project. You'll need a clip for every bulb installed on the cord to create a sharp, clean line.

The clip used in the featured image for this post is the All in One Clip. A classic, it has been a customer favorite for over 15 years.

4. Gilbert Plugs

One of the best advantages of using 18 AWG wiring for a Christmas display is having the ability to cut the cords to fit. Once cut, the cords will need plugs. The easiest style of plug to use is the gilbert or vampire style plug. You'll need a male plug for each place the cords are cut at the beginning of a line. Female connectors can be used to terminate a line or combined with bulk wire can be used to create custom cords without sockets to jump between windows or roof peaks.

Here is a handy post about how to determine how many plugs to purchase.

Additional tips:

  1. Regardless of the style of bulb used, never run more than 250 feet of 18 AWG Christmas cord (including any bulk wire jumpers) in a single circuit. This is the maximum light line specification for 18 AWG cord.
  2. Add the wattages of bulbs used per breaker to ensure that you don't exceed 80% of the maximum current load. If you have questions about your electrical service and installation, be sure to reach out to a Master Electrician for professional assistance.
  3. Test cords and bulbs by building cords before installation. Where applicable, install clips on sockets before beginning installation.
  4. Power lights with outside rated surge protectors to protect your investment.

Pin and save for later!


Additional Reading