How to Install De-Icing Cables to Stop Roof Ice Dams
De-icing cables work by preventing the formation of ice dams. Ice dams are caused when snow and ice on the roof repeatedly freezes and thaws on the roof. This allows the ice to force itself between the shingles, and later causes roof leaks. By preventing ice dams from forming in typical locations, such as near rain gutters, de-icing cables prevent the damaging freeze thaw cycle from starting by melting any ice forming on the shingles.
Installing de-icing cables is an easy job, but should only be attempted when the roof is completely dry. For this reason, plan ahead and schedule this home improvement project for the fall. If winter has already started, you can hope for a thaw that will allow you to install these cables, but de-icing cables cannot be installed if there is any snow on the roof.
De-icing cables often come in a kit that includes the thermostat, control box, and hardware required to complete the installation of the entire system. Check your local home improvement store for a kit that is appropriately sized for your particular home size and needs.
To install the de-icing cables you should begin by screwing the control box in a location that is easily accessible but also protected from the rain. The control box should also be close to an electrical socket. Underneath a soffit on your home is often a good location. Keep in mind that your electrical source should have a ground fault circuit interrupter to prevent accidental electrical shocks.
With the control box installed, you should then attach the heating cables to the roof. You should plan on using a zig zag pattern that will cover the last 24 inches of the roof. This distance is normally used because it does not have the heated area of the house underneath this part of the roof. If your roof uses different proportions, you should follow those particular proportions to get the best results out of your de-icing cables.
Of course, you should read and follow any instructions that come with your de-icing cable kit. Most heating cables are attached to the roof using roof cable clips that are included in a standard kit. These clips attach to the edges of your shingles, eliminating the need for holes in your roofing.
When installing your de-icing cables, pay particular attention to the valleys in your roof. For these areas, you should plan on extending the de-icing cables at least 36″ up the valley, directly on the flashing. This will allow the de-icing cables to address areas where ice build up is common. You should still be able to use the roofing clips to attach to the valleys, just use several on both sides of the flashing to attach the cable securely.
When you reach the end of your roof, stick the end of the cable into the rain gutter on your house and run the remaining cable the length of the gutter. Your kit should have clips to keep the end into place. Any excess cable should be threaded down the gutter’s downspout.
Finally you should attach the sensor wire near the heating cable in the same zig zag pattern. Allow for a two inch gap between the two wires. Attach the thermostat block to the sensor wires, and attach the sensor to the control box.
Installing de-icing cables is a good way to prevent roof leaks in areas where snowfall and ice are a concern. Of course if you are not comfortable on a ladder or need an electrical outlet installed to begin this project, call a professional who will be able to complete the job before the snow flies.
