How Much Do Roof Heat Cables Cost To Run?

Sunday, January 8, 2012 6:40:00 AM

With energy costs rising, pocket books shrinking, and energy consumption becoming an increasing concern, one should consider the operating cost of a Roof and Gutter Ice Dam Prevention System. Several factors go into estimating operating costs.

The Type of Heat Cable:  There are two basic types of heat cable that can be used on the roof. The first is the constant wattage. These are the thin round heat cables that are typically purchased at hardware or big box stores. They can also be ordered online. These heat cables use the same amount of energy with no ability to regulate power usage unlike the second type - self regulating heat cables. Constant wattage cables are more delicate and usually have a much shorter life span. These heat cables are usually selected by homeowners who want to tackle the project themselves, but are also used by contractors who are less concerned with a long lasting installation and more concerned with how inexpensively they can purchase these heat cables. As mentioned, the second type is the self regulating heat cable. These heat cables have the ability to regulate the amount of energy used all along the heat cable. As the heat cable warms, the cable adjusts the power usage to limit or regulate the actual temperature or heat output of the cable. This is the reason why these heat cables generally last so long. Even if they come into contact with themselves or are overlapped, their self regulating ability prevents them from burning out.

Length of Heat Cable Used:  It may seem simplistic, but the length of the heat cable also contributes to the cost of running them. Constant wattage cables come with predetermined lengths in the box. Power usage is usually given on the back of the box. A typical constant wattage cable might use 5 watts per foot no matter what the temperature is outside. So, if the cable is 100 feet long, it will use 500 watts per hour. Electricity is paid for in watts, not amps or volts. To calculate, take your cost per kilowatt/hr and multiply by watts of the heat cable. In the above example: 500 kilowatts/hr = .5 kw/hr x (your cost per kilowatt/hr) = Your Cost of Operation. Self Regulating Heat Cables use different amounts of energy based on the outside temperature and whether the cables are in snow, water or ice. The cables do list a wattage based on wattage used at a given temperature. So heat cable manufacturers also provide a table that lists the self regulating curve or arc. This shows the amount of power used through a range of temperatures. For our discussion, use the temp/wattage listing for @ 32 degrees. Then, the calculation is the same as given above. The calculation is: length of heat cable used x wattage of heat cable x cost per kilowatt/hr.

Use the Energy Wisely:  When heat cables are run in a zig zag fashion on the roof, more heat cable is need to accomplish what is intended to do. When heat cables are used in conjunction with thermally conductive materials, greated melting capacity is achieved with less heat cable resulting in lower overall operating cost year after year. As an added benefit, the heat cables are also protected from damage. The Bylin Roof Ice Melt System and VersaScreen IceBlaster are two outstanding products that combine self regulating heat cable technology with thermally conductive materials. For more information please Contact Us.