Prevent Icicles & Ice Dams on Your Building
Winter can be tough on commercial and industrial buildings, with snow and ice accumulating on roofs and gutters. King ’s advanced electric de-icing systems efficiently melt ice, ensuring your building is protected from snow damage, while preserving the visual appeal of your building.
Dependable, Field- Proven Durability
Most roofs can only support 20 lbs of snow per square foot before the risk of collapse arises. Self-regulating roof de-icing systems provide a reliable solution by maintaining a clear path for melting water to drain safely. King’s self-regulating roof heating cables are versatile for various climates and are built to withstand extreme weather conditions, including high winds, low temperatures, and heavy snow loads.
Calculation For Heating Cable Length
Total heating cable length = A+B+C+D+E+F+G
A (Roof edge) x (heating cable multiplier)
B (Roof edge x 0.5)
C (Total gutter length)
D (Total downspout length + 1 ft.)
E (1 ft. for each power connection)
F (2 ft. for each splice)
G (3 ft. for each tee connection)
=Total heating cable length required.
Example:
1. Roof edge = 48 ft.
2. Eave overhang = 1 ft. (Refer to cable table 6)
3. Gutter = 48 ft.
4. Downspout = 22 ft.
5. Power connection = 2 each
6. Splice = 3 each
Heating Cable Required:
A Roof edge: 48 ft. x 2.8 (From table 6) = 134.4 ft.
B Roof extension*: 48 ft. x 0.5 = 24.0 ft.
C Roof gutter: 48 ft. = 48.0 ft.
D Downspout: 22 ft. + 1 ft. = 23.0 ft.
E Power Connection: 2 x 1 ft. = 2.0 ft.
F Splice Connection: 3 x 2 ft. = 6.0 ft.
G Tee Connection: 0 x 3 ft. = 0 ft.
Total heating cable length required: = 237.4 ft.
*Roof extension is the length of cable required to prevent ice dams between the roof edge and the gutter. When there are no gutters present it forms a drip loop to prevent s at the roof edge.
Use the number in the table and multiply it by the length of the roof
Calculations for Gutters, Downspout and Valley
1. For standard non-metal roofs, add 1 foot of heating cable for each foot of gutter.
2. Add 1 foot of heating cable per foot of downspout.
3. If the downspout is in the middle of the run, loop the cable down and back up. Double the length of the downspout for determining the length of the cable to install.
4. For valleys, run the heating cable two thirds of the way up and down the valley. Add this additional length to the overall cable.
5. For gutters 6 inches wide use two cable runs.
Design Notes
1. In-line splices and tee splices should be avoided where possible.
2. Heating cable in downspouts should be looped and extend below the frost line if tied into a drainage system.
3. End terminations should not be located in an area where moisture is present. End terminations should not be located at the lowest point of downspouts.
4. For roof drains leading into a heated area, a loop of heating cable should be installed to a depth of 3 ft.
