Heating an existing driveway or sidewalk is possible via a retrofit installation. While we have written a fair amount about this option elsewhere, this is intended to provide a basic overview of the retrofit installation process and what to expect.
Prepare for Controls and Panels
Determine where your controls will be installed. If you are heating a driveway we recommend somewhere near the front of your garage to minimize the distance to the heated area. Once this is determined you will need to have an electrical contractor bring power from your distribution panel to the control unit or relay panel. Power will also need to be provided for any sensors, timers, or other activation devices.
Design and Mark Layout
Once you have determined the area of the driveway you would like to heat, you can begin planning the layout of the heating cables. Keep in mind the cables are installed in loops and both ends should come back to your control unit or relay panel.
We recommend using a chalk line to mark the cable layout on the surface to be heated. The spacing between runs of cable will be determined by the product you choose and the heat density you wish to provide. This information can be found on the bid you receive from our experts.
When finished, be sure to measure your layout and verify the lengths match the cables you are planning to install.
With the layout marked with the chalk line you are read to cut the grooves for the heating cable. If you are using Hott-Wire, the cuts will be ⅜” wide and 1 ½” deep. If you are installing Tuff Cable, the grooves will be ¼” wide and 1” deep. You should also make saw cuts for the cold leads to return to your control unit or relay panel.
To avoid damaging the cables, a hammer drill should be used to knock out the corners of your grooves.
Cutting concrete and asphalt makes a big mess. You will want to power wash the area, taking care to remove debris from the grooves and surrounding area. The area should then be allowed to dry completely before installing the cables.
Installing the Cables
The Hott-Wire or Tuff Cable can now be installed in the grooves. The cable is installed along the bottom of the grooves in the pattern you previously designed. Once the cables are in place, a foam backer rod is installed over the cable and then the saw cuts are filled with the appropriate sealant for your project.
With the cable installed, an electrician can make the final connections to the control unit or relay panel. Activation devices will need to be installed and connected to the system.
Throughout the installation remember to follow the testing procedures outlined in the installation manual. This ensures the cable is properly functioning and not damaged during installation. The results of these tests should be recorded in the manual that came with your system.