If snow and ice accumulate on your roof, installing a roof heat cable is an easy and effective to solution to melt the ice dams before they cause major damage.
How To Estimate Roof Heat Cable LengthYou will need to measure your roof eaves (horizontal roof edge where gutters are attached) - this will be the value of "Roof Length". Enter this into the calculator.
If you have valleys with ice dam problems, also include total length of valley, where you will install the cable.
Loop Height: we recommend the loop height to be 12" longer than your overhang - this will ensure that your heat cable is melting the ice 6" past the exterior wall of your house. Note that manufacturer's recommendation is overhang width + 6". However, in our experience this is not enough to properly remove ice dams.
Also consider that steeper roofs definitely need loop height to be at least 12" longer than overhangs. A 12/12 slope increase distance up the slope by a factor of 1.41 - therefore if your overhang is 24", you need 36" loop height just to get in line with the outside of the exterior wall.
Loop Spacing: the loops are spaced 24" between peaks and valleys horizontally, and a clip is place every one foot of roof edge. There are 19 clips per pack. Divide the roof edge length by 19 (and round up) to get the number of clips that you will need.
Estimate Electric Circuit LoadMost roof heating wire products are 110V, with rated electric use of 8W per linear foot. This means that you should not install more than 190 feet of heat wire on a single 15A circuit.
Also keep in mind that you need to run your cable from the nearest power outlet to the roof - a distance that is about 15 feet on average (unless you run your waterproof extension cord right to the roof).
Because most people will plug in their heat cables directly into an exterior power outlet, we add 15 feet to the total cable length.
Moreover, if you are using a 200' or 240' long heat wire, you should absolutely plug it into a 20A outlet. Otherwise, you will overload the circuit, and your breaker will pop. This can cause unwanted ice dams damages, while you may be unaware that your deicing system is not working.
Roof Heating Cable Operating CostsAs mentioned above - you will use about 8W per linear foot of ice-melting cable. A typical 120 foot long roof edge with 6-12" overhangs and no gutters deicing, will need about 291 feet of cable. That equals to 2.3kWh per hour or almost 56kWh per day of continuous operation.
With US average electric price of $0.13/kWh, you will be spending $7.25 per day, if your system is running full 24 hours. A full month of non-stop operation would cost about $217.
In Massachusetts, our electric costs are about $0.23 / kWh. This means that running the deicing cables for a full day would cost me almost $13/day or $385 per month!!!
To prevent your system from being on all day and wasting electricity, you can either manually turn it off (when there is no snow/ice on the roof), or use a snow/ice sensor. It will automatically turn off the power, and save you tons of money on operating costs!
These sensors are designed for a maximum of 120' of cable length and 1200W max load.
Roof Heat Cable Installation Costs - DIY vs Hire A ProIt is fairly simple to install this system yourself - all you need is a ladder that is long enough to reach your roof, and a ladder stabilizer bar to make sure it doesn't slide to the side, and to prevent falls / injuries.
DIY - Here is a complete installation guide for easy heating products, which can also be used as a reference for other brands.
If you opt for hiring a roofer - we still recommend that you buy the materials yourself, and agree on a set price for installation labor only. The reason for this is that most contractors will put 50-100% premium on materials, so you can save $100-300 if you purchase everything yourself.
The average cost to install 100 feet of heat cable on the roof only is about $300-400 (labor only, excludes materials). When you add materials, at the price of about $2/sq. ft., you are looking to spend about $200 for 100 feet of cable. Thus your total cost when hiring a contractor will be $500-600.
Putting heat cables inside gutters and downspouts will add about $200-300 for every 100 feet of roof edge length.
Remove Snow Before it Freezes, and Turns into IceIt's ideal to REMOVE snow from your roof before ice dams are formed. While there are numerous types of snow rakes out there, most of them you have to press down onto, and scrape the snow of the roof.
This "pressing down" onto a snow rake, will give you muscle aches and can possibly hurt your back. Also, if your rake edge (blade) is metal, you can scrape granules of your roof shingles, and damage them. If edge (blade) is made from foam, that foam will break quickly, and you will need to get a new one.
This is where Avalanche snow rake excels! With patented "snow sliding mat" on the bottom, all you need to do is push avalanche rake up the roof.
Avalanche will cut into snow, and blocks of snow will simply slide down! Now need for you to push onto snow, and pull it off the roof!
Why Is Ice Dam Prevention So Important?The obvious reason for protecting your roof from ice dams is that they cause serious damage to the roof itself and in worst case scenarios to the interior of your home. Here are some of the most common problems that a built-up of ice can create:
- Roof leaks
- Loose or damaged shingles that need to be replaced
- Torn off or damaged gutters
- Wet attic insulation that will need to be replaced
- Mold in the attic
- Stains on the ceilings and floors of the top floor in your house
- Chipping or peeling interior paint
Typically, if ice dams are not dealt with in a timely fashion, the destruction they do is compounded - in other words you will be seeing a number of issues from this list all at once.
The average cost of repairs is $1,500-2,500+, depending on what needs to be done. However, it can be as high as $7,000+ if your home will require mold remediation.
Ultimately, its all about the cost. Spending money upfront on an expensive and advanced roof-deicing product, such as Perfectly Clear, costs significantly less than repairing damages from unruly ice dams.
What is the BEST solution for ice dams?
When it comes to products that can help fight ice dams, there are many options to choose from, ranging from very cheap to very expensive.
Here are a couple of questions to think about to help you choose the right solution?
1. Does your home routinely have serious ice dams every winter? If your house does not have major problems with ice and snow, spending a lot of money on expensive systems may not make sense.
2. Do you regularly spend money on cheap ice dam solutions and sometimes roof repairs? In this case, you may want to consider more advanced, permanent solutions.
3. Do you have an old roof that needs to be replaced this season? If so, you may want to consider installing a metal roof. While its very costly ($9,000-13,000 for a 1,500 sq. ft. roof), it provides a permanent solution to leaks, ice dams and all roof related problems.
Take a look at the chart below that summarizes various products and solutions for ice damming, as well as their approximate cost. Compare and see which one would work for you.
|Short - Term / Easy||Cost||Long - Term / Advanced||Cost|
|Ice - melt socks||$||Add blown - in roof insulation||$$$|
|Ice pucks||$||Improve ventilation||$$$|
|Snow rake||$||Advanced 240 v heating cables (professional install only)||$$$$|
|Roof heating cables (DIY install)||$$||Metal ice belt (professional install only)||$$$$|
|Professional ice dam removal with steam||$$||Special Ice melting system (professional install only)||$$$$|
Average New Metal Roof Costs In US:
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