Time: 3 hours
So, you already tried to stop ice dams from forming, but did it work? Trust us, you do not want these dangerous ice ridge formations (and the puddles they hide) camping out on your roof, just waiting to rip off your gutters and send water all the way down to your foundation. Time to level up the efforts — install heat cables to melt ice dams before you have a watery mess to deal with.
What's in it for you?
- Extend your roof’s lifespan
- Stop water intrusions
- Lower the likelihood of falling ice
Install Heat Cables to Melt Ice Dams
Measure your roof. Measure the roof edge along which you’ll be installing the cable, allowing for a little extra when there are dormers, valleys, gutters, and downspouts to go around. The total area you want to cover is largely up to you, but make sure to focus on areas where you see ice accumulating or that are especially hard to reach from the ground (like roof overhangs and eaves).
Get the heat cables. Head over to your local hardware store and get some heat cables. (Make sure to take a picture of your home’s exterior with you — there are different types of cables and it’s important to get the right ones.) Most are designed to be installed in a zig-zag pattern, so you’ll need to multiply the measurements you took earlier depending on how deep your eaves and overhangs are. For example, one brand says to multiply by 5.3 for a 24-inch overhang.
Ladder up so you can install the cables. Before you climb up, use a roof rake to remove excess snow from your roof. This will give you a cleaner working area and easier access to the ice. When you’re done, grab that ladder and set it to a height where you can comfortably reach the roof. Position it so it’s at the edge of your roof that runs perpendicular to the eaves you’ll be lining. Don’t forget to phone a friend for help — safety first, people.
Install the roof heat cable in a zigzag pattern. Grab a shingle clip and clip your heat cable to a shingle that’s above the spot where your eaves meet the wall they’re overhanging. Zigzag the cable along the roof’s edge, forming triangles that are about 15” wide at the base. When you hit the gutter, grab the shingle clip with two cable holders. Slide it under a shingle above the gutter, and attach your cable twice so it forms a loop hanging a few inches down.
Run some cable along your gutters. If you have enough excess heat cable after lining your roof’s edge, you can run the end back through your gutter and down the downspout. If you do, clip the cable to the drip loops you left at the bottom of each triangle in step 4. Or run a second cable through your downspout down to the outlet.
Plug the cables in. Make sure you’re using a ground fault circuit interrupter outlet — these have built-in circuit breakers designed to prevent electric shock, so look for an outlet with “TEST” and “RESET” buttons. Things should start to warm up as soon as you plug the cable in. Don’t have a GFI outlet? Stay safe and call an electrician to install one.
Pro Tip: You also can loop heat cables around dormers (those windows projecting out from your roof) and along valleys (the notch where different roof sections meet at an angle) to melt ice dams in those areas.