Two winter conveniences, two very different electrical loads, and the questions to answer before either goes in
Credit: Homeowner.ca
Most people shopping for a heated driveway think they're buying convenience. What they're really buying is an electrical load, and a big one: larger than a range, a dryer and an EV charger put together. Roof de-icing cable gets the opposite misunderstanding. People think they're buying a fix for ice dams. What they're getting is a drainage channel through a problem that starts somewhere else.
Both systems can be worth it. Some homeowners will find them essential. Each one carries a cost the brochure leaves out, though. For the driveway it's the electrical service. For the cable it's the attic. If you understand those two costs, the decision mostly makes itself.
This guide works through both systems with real numbers: manufacturer power ratings converted into kilowatts for typical Canadian driveways and rooflines, the Canadian Electrical Code arithmetic your electrician will run, what permits look like in four provinces, and operating costs built from published Ontario and Quebec rate schedules. It ends in a load-and-conditions table you can hold up against your own house.
Start with physics, not price. Both systems turn electricity into heat at a rated density, so the load follows from two numbers: how much surface you're heating and how many watts each unit of it takes.
Electric snow-melt mats and cables are rated in watts per square foot. WarmlyYours' 240-volt Snow Melt PowerMat is a good reference point: 2,000 watts across 40 square feet, or 50 W per square foot, CSA-certified for outdoor use and rated for asphalt, concrete or mortar under pavers.
Other manufacturers land in the same band. Thermosoft's NeverFreeze mats are specified between 38 and 51 W per square foot depending on cable spacing, with 40 W common. The manufacturer says its systems melt about two inches of snow an hour. That's a claim, not a test result, but it explains why the industry settles here. Lower densities melt more slowly. Higher densities cost more to run and need more circuit capacity.
So the working range is 40 to 50 W per square foot. Here's what that does to real driveways:
That last line deserves a second read. A 100 A service at 240 volts has a nominal capacity of 24 kW. A fully heated double driveway at 50 W per square foot asks for all of it, before the house turns on a single light.
Roof de-icing cable is rated in watts per linear foot, and it comes in two types.
Constant-wattage cable produces the same heat along its length no matter the conditions. Plug-in kits sold at Canadian retailers are typically 5 W per foot at 120 volts, from a 20-foot kit at 100 W up to 240-foot kits at 1,200 W. They're CSA- and cUL-listed, and they can't be cut to length. You buy the kit that fits.
Self-regulating cable changes its output with its surroundings. Raychem publishes the IceStop cable's output as 36 W per metre at 0°C in ice water and 18 W per metre at 0°C in air. That's about 11 W per foot in slush and 5.5 W per foot in dry cold. The cable draws the most when it's doing the most work, which is efficient and also makes the load harder to predict.
Now the roofline. A cable layout on 60 feet of eave isn't 60 feet of cable. It zigzags across the roof edge, runs the length of the gutter and drops down each downspout. With two downspouts, a realistic run is around 240 feet. That's our layout estimate, and your installer's will depend on overhang depth and pitch.
At 5 W per foot, 240 feet of constant-wattage cable draws about 1.2 kW, roughly 10 A at 120 volts. The same run in self-regulating cable draws about 1.3 kW in dry cold air, rising toward 2.6 kW when the cable sits in meltwater.
Compared with a driveway, roof cable is a small load. Small doesn't mean trivial, though. It can run for days at a stretch, as the operating-cost section shows.
Gutter guards change how cable sits and drains, so read up on the interaction before you combine them.
Eavestrough Guards and Winter: Ways to Reduce Ice Buildup Without Creating Drainage Problems
Start with physics, not price. Both systems turn electricity into heat at a rated density, so the load follows from two numbers: how much surface you're heating and how many watts each unit of it takes.
Electric snow-melt mats and cables are rated in watts per square foot. WarmlyYours' 240-volt Snow Melt PowerMat is a good reference point: 2,000 watts across 40 square feet, or 50 W per square foot, CSA-certified for outdoor use and rated for asphalt, concrete or mortar under pavers.
Other manufacturers land in the same band. Thermosoft's NeverFreeze mats are specified between 38 and 51 W per square foot depending on cable spacing, with 40 W common. The manufacturer says its systems melt about two inches of snow an hour. That's a claim, not a test result, but it explains why the industry settles here. Lower densities melt more slowly. Higher densities cost more to run and need more circuit capacity.
So the working range is 40 to 50 W per square foot. Here's what that does to real driveways:
That last line deserves a second read. A 100 A service at 240 volts has a nominal capacity of 24 kW. A fully heated double driveway at 50 W per square foot asks for all of it, before the house turns on a single light.
Roof de-icing cable is rated in watts per linear foot, and it comes in two types.
Constant-wattage cable produces the same heat along its length no matter the conditions. Plug-in kits sold at Canadian retailers are typically 5 W per foot at 120 volts, from a 20-foot kit at 100 W up to 240-foot kits at 1,200 W. They're CSA- and cUL-listed, and they can't be cut to length. You buy the kit that fits.
Self-regulating cable changes its output with its surroundings. Raychem publishes the IceStop cable's output as 36 W per metre at 0°C in ice water and 18 W per metre at 0°C in air. That's about 11 W per foot in slush and 5.5 W per foot in dry cold. The cable draws the most when it's doing the most work, which is efficient and also makes the load harder to predict.
Now the roofline. A cable layout on 60 feet of eave isn't 60 feet of cable. It zigzags across the roof edge, runs the length of the gutter and drops down each downspout. With two downspouts, a realistic run is around 240 feet. That's our layout estimate, and your installer's will depend on overhang depth and pitch.
At 5 W per foot, 240 feet of constant-wattage cable draws about 1.2 kW, roughly 10 A at 120 volts. The same run in self-regulating cable draws about 1.3 kW in dry cold air, rising toward 2.6 kW when the cable sits in meltwater.
Compared with a driveway, roof cable is a small load. Small doesn't mean trivial, though. It can run for days at a stretch, as the operating-cost section shows.
Gutter guards change how cable sits and drains, so read up on the interaction before you combine them.
Eavestrough Guards and Winter: Ways to Reduce Ice Buildup Without Creating Drainage Problems
This is the question to answer first. A $6,000 quote for heating mats means little if the house also needs a new service to run them.
When an electrician or inspector checks whether a house can take a new load, they use the single-dwelling calculation in Rule 8-200 of the Canadian Electrical Code. The City of Vancouver's load calculation worksheet for the 2024 code lays it out step by step. It starts with 5,000 W for the first 90 m² of living area, plus 1,000 W for each additional 90 m² or part of it. Electric space heating counts at 100% of the first 10 kW and 75% of anything above that. Air conditioning counts at 100%. An electric range counts as 6,000 W, plus 40% of its rating above 12 kW. Tankless water heaters, hot tubs, pools and EV chargers count at 100%. Any other load over 1,500 W counts at 25% of its rating where the house has an electric range.
The total, divided by 240 volts, gives the calculated load in amps. That number has to fit within the service rating.
The calculation also sets a floor. Alberta's City of Grande Prairie inspection worksheet repeats the rule: a dwelling with 80 m² or more of living area (excluding the basement) needs at least a 100 A service. That's why so many older Canadian houses have exactly 100 A. It's the minimum the code allows, not a sign of spare capacity.
Neither worksheet has a line for snow melting. The code's demand-factor relief in Section 62, the 75% treatment above 10 kW, applies to space heating. A driveway doesn't heat a space.
So where does it go? Read literally, a snow-melt system falls into the catch-all "other loads over 1,500 W," counted at 25% in a house with an electric range. In practice, many electricians don't count it that way. An Alberta contractor's published Section 8 calculator puts it plainly: snow melt is counted at 100%, with the breaker sized at 125%.
The physics backs the electricians. A snow-melt system runs at full nameplate for hours during a cold storm, which is exactly when the furnace blower, the range and everything else in the house are running too. A 25% allowance assumes the load comes and goes. This one doesn't.
How your system gets counted is a call for your electrician and your inspector, not this article. What you can do is run the arithmetic both ways and see which answer you're living with.
Take a 150 m² house (living area, excluding the basement) with gas heat, a 12 kW electric range, a 3.5 kW central air conditioner, a 5.5 kW dryer and a 3 kW tank water heater. The basic load is 6,000 W, the range adds 6,000 W, the air conditioner 3,500 W, and the dryer and water heater 2,125 W at 25%. That's a calculated load of 17,625 W, or about 73 A.
Now add the driveway options:
The pattern is clear. On a 100 A service, tire tracks are roughly the ceiling. A full single-car strip pushes the service to its limit or past it, depending on how it's counted. A double driveway is a service-upgrade project that happens to include some heating mats. In an all-electric house, where space heating already takes most of the calculation, even tire tracks may not fit.
Roof cable mostly stays out of this problem. At 1.2 kW, a constant-wattage kit sits below the 1,500 W threshold entirely, and a self-regulating run usually adds well under 15 A. Its effect on the service is a rounding error next to a driveway's.
This is the question to answer first. A $6,000 quote for heating mats means little if the house also needs a new service to run them.
When an electrician or inspector checks whether a house can take a new load, they use the single-dwelling calculation in Rule 8-200 of the Canadian Electrical Code. The City of Vancouver's load calculation worksheet for the 2024 code lays it out step by step. It starts with 5,000 W for the first 90 m² of living area, plus 1,000 W for each additional 90 m² or part of it. Electric space heating counts at 100% of the first 10 kW and 75% of anything above that. Air conditioning counts at 100%. An electric range counts as 6,000 W, plus 40% of its rating above 12 kW. Tankless water heaters, hot tubs, pools and EV chargers count at 100%. Any other load over 1,500 W counts at 25% of its rating where the house has an electric range.
The total, divided by 240 volts, gives the calculated load in amps. That number has to fit within the service rating.
The calculation also sets a floor. Alberta's City of Grande Prairie inspection worksheet repeats the rule: a dwelling with 80 m² or more of living area (excluding the basement) needs at least a 100 A service. That's why so many older Canadian houses have exactly 100 A. It's the minimum the code allows, not a sign of spare capacity.
Neither worksheet has a line for snow melting. The code's demand-factor relief in Section 62, the 75% treatment above 10 kW, applies to space heating. A driveway doesn't heat a space.
So where does it go? Read literally, a snow-melt system falls into the catch-all "other loads over 1,500 W," counted at 25% in a house with an electric range. In practice, many electricians don't count it that way. An Alberta contractor's published Section 8 calculator puts it plainly: snow melt is counted at 100%, with the breaker sized at 125%.
The physics backs the electricians. A snow-melt system runs at full nameplate for hours during a cold storm, which is exactly when the furnace blower, the range and everything else in the house are running too. A 25% allowance assumes the load comes and goes. This one doesn't.
How your system gets counted is a call for your electrician and your inspector, not this article. What you can do is run the arithmetic both ways and see which answer you're living with.
Take a 150 m² house (living area, excluding the basement) with gas heat, a 12 kW electric range, a 3.5 kW central air conditioner, a 5.5 kW dryer and a 3 kW tank water heater. The basic load is 6,000 W, the range adds 6,000 W, the air conditioner 3,500 W, and the dryer and water heater 2,125 W at 25%. That's a calculated load of 17,625 W, or about 73 A.
Now add the driveway options:
The pattern is clear. On a 100 A service, tire tracks are roughly the ceiling. A full single-car strip pushes the service to its limit or past it, depending on how it's counted. A double driveway is a service-upgrade project that happens to include some heating mats. In an all-electric house, where space heating already takes most of the calculation, even tire tracks may not fit.
Roof cable mostly stays out of this problem. At 1.2 kW, a constant-wattage kit sits below the 1,500 W threshold entirely, and a self-regulating run usually adds well under 15 A. Its effect on the service is a rounding error next to a driveway's.
Canadian quote platforms describe a panel and service upgrade as a routine part of heated-driveway pricing, not an exception. If the first quote you get doesn't mention your service size, it isn't a complete quote yet.
The service calculation decides whether a system can go in. Section 62 of the code, which covers fixed electric heating, decides how it goes in. Three requirements matter most to a homeowner reading a quote.
Rule 62-116 requires ground-fault protection on heating cable sets. According to the 26th-edition road map to Section 62, this protection guards equipment against fire, not people against shock. It's set high enough to let the heater run normally but trips on a sustained, high-resistance arcing fault, the kind that develops when a cable jacket is nicked by a shovel or crushed under a paver.
That's why these systems use ground-fault equipment protection (often a 30 mA breaker or controller) rather than the 5 mA GFCI receptacle by your back door. Plugging a long run of cable into a standard GFCI outlet often leads to nuisance trips. Raychem's IceStop manual specifies a 30 mA trip on every circuit.
Rule 62-304 requires heating cable under driveways, sidewalks and similar surfaces to be embedded or covered at least 50 mm below the finished surface. That shapes the job. Mats go into the concrete pour, into the asphalt base or into the mortar bed under pavers. They don't go on top of an existing driveway.
A snow-melt system easily meets the code's definition of a continuous load: more than one hour in any two-hour period. Under Rule 8-104, as the IAEI explains, a continuous load can't exceed 80% of the rating of a standard breaker. In practice, the breaker capacity needs to be about 125% of the load. A 10 kW single-car system drawing 42 A needs about 52 A of breaker capacity, usually split across several circuits. A 24 kW double driveway needs about 125 A of breaker capacity, which is more than an entire 100 A panel.
The service calculation decides whether a system can go in. Section 62 of the code, which covers fixed electric heating, decides how it goes in. Three requirements matter most to a homeowner reading a quote.
Rule 62-116 requires ground-fault protection on heating cable sets. According to the 26th-edition road map to Section 62, this protection guards equipment against fire, not people against shock. It's set high enough to let the heater run normally but trips on a sustained, high-resistance arcing fault, the kind that develops when a cable jacket is nicked by a shovel or crushed under a paver.
That's why these systems use ground-fault equipment protection (often a 30 mA breaker or controller) rather than the 5 mA GFCI receptacle by your back door. Plugging a long run of cable into a standard GFCI outlet often leads to nuisance trips. Raychem's IceStop manual specifies a 30 mA trip on every circuit.
Rule 62-304 requires heating cable under driveways, sidewalks and similar surfaces to be embedded or covered at least 50 mm below the finished surface. That shapes the job. Mats go into the concrete pour, into the asphalt base or into the mortar bed under pavers. They don't go on top of an existing driveway.
A snow-melt system easily meets the code's definition of a continuous load: more than one hour in any two-hour period. Under Rule 8-104, as the IAEI explains, a continuous load can't exceed 80% of the rating of a standard breaker. In practice, the breaker capacity needs to be about 125% of the load. A 10 kW single-car system drawing 42 A needs about 52 A of breaker capacity, usually split across several circuits. A 24 kW double driveway needs about 125 A of breaker capacity, which is more than an entire 100 A panel.
All four provinces checked here treat a new snow-melt or de-icing circuit as electrical work that needs a permit, notification or declaration. Who's allowed to do the work varies.
Plug-in roof kits feel like an appliance purchase, but a permanent circuit for one is still electrical work. If your electrician adds a dedicated outdoor circuit and controller for the roof cable, expect the same notification or permit process.
This is where roof cable gets oversold, and where the most useful correction lives.
An ice dam isn't a roof-edge problem. It's an attic problem that shows up at the roof edge. Natural Resources Canada explains that warm attic air heats the roof deck, snow melts against it, and the meltwater runs down to the cold overhang and refreezes. Each cycle builds the ridge higher until water backs up under the shingles.
The federal guidance is blunt about the fix: air sealing comes first, and its importance "cannot be overstated." NRCan also warns that adding insulation without sealing air leaks can make ice damming worse. Warm, moist air keeps escaping, and now it does so into a colder attic.
The clearest statement about heat cable's limits comes from a cable manufacturer. Raychem's IceStop installation manual describes the system's job as maintaining a continuous path for meltwater to drain off the roof. It doesn't claim to prevent ice dams, remove snow or reduce snow loads.
That's an honest product description, and it shapes the decision. Cable lets water escape through a dam that's still forming. The heat loss that feeds the dam keeps going, and so does the energy bill for it, through the ceiling and then through the cable.
None of this makes cable useless. Some ice problems can't be fixed from the attic:
In these cases, cable targets a known location that has no attic fix. That's the condition the conditions table relies on.
For the attic-side fixes and the wider set of winter roof problems, start here:
Ice Dams, Snow Loads & Winter Roofing Problems: A Survival Guide for Canadian Homeowners
Wattage sets how much power a system draws per hour. Controls decide how many hours it runs. Over a winter, hours matter more.
Manufacturers rarely publish numbers for the difference. WarmlyYours Canada says automatic sensors can cut operating costs by up to 70% compared with manual timers. Treat that as a manufacturer's claim.
Other control makers describe the same savings features without putting a figure on them. Heat-Timer's description of its multi-sensor control is typical: it keeps pavement clear "with the minimum amount of energy," and says no more than that.
Raychem lists the same tiers for roof cable: manual switching, which needs constant attention; an ambient thermostat that turns the cable on whenever it's below freezing; and an automatic controller with gutter moisture and snow sensors, which the manual calls the most conservative choice for energy use.
The ambient thermostat is the trap. In much of Canada, "below freezing" describes most of December through February. A cable on an ambient thermostat isn't responding to ice. It's responding to winter.
Wattage sets how much power a system draws per hour. Controls decide how many hours it runs. Over a winter, hours matter more.
Manufacturers rarely publish numbers for the difference. WarmlyYours Canada says automatic sensors can cut operating costs by up to 70% compared with manual timers. Treat that as a manufacturer's claim.
Other control makers describe the same savings features without putting a figure on them. Heat-Timer's description of its multi-sensor control is typical: it keeps pavement clear "with the minimum amount of energy," and says no more than that.
Raychem lists the same tiers for roof cable: manual switching, which needs constant attention; an ambient thermostat that turns the cable on whenever it's below freezing; and an automatic controller with gutter moisture and snow sensors, which the manual calls the most conservative choice for energy use.
The ambient thermostat is the trap. In much of Canada, "below freezing" describes most of December through February. A cable on an ambient thermostat isn't responding to ice. It's responding to winter.
No article can give you your bill. What it can give you is the formula and two honest worked examples:
kW × hours of operation × your price per kWh = energy cost
The prices below are the electricity commodity rate only. Delivery charges, regulatory charges, tax and any provincial rebate appear separately on your bill.
The Ontario Energy Board's current prices, in effect until October 31, 2026, set winter time-of-use rates at 9.8¢ per kWh off-peak, 15.7¢ mid-peak and 20.3¢ on-peak. The ultra-low overnight plan charges 3.9¢ from 11 p.m. to 7 a.m. but 39.1¢ on weekday evenings from 4 to 9 p.m. The OEB resets prices every November 1, and the 2026–27 prices hadn't been announced at the time of writing.
Applied to the worked systems, a 10 kW single-car strip costs about $0.98 an hour off-peak, $2.03 on-peak and $3.91 at the ultra-low-overnight plan's on-peak price. A nine-hour storm event (six hours of snowfall plus a three-hour hold-on) uses 90 kWh: about $8.82 off-peak or $18.27 on-peak. The same event on a 24 kW double driveway uses 216 kWh, about $21 off-peak or $44 on-peak.
On the ultra-low overnight plan, timing becomes a bigger factor than wattage. A snowfall that starts at 4 p.m. on a weekday costs ten times as much per kWh as the same snowfall at midnight.
Hydro-Québec's Rate D, effective April 1, 2026, charges 7.065¢ per kWh for the first 40 kWh a day and 11.142¢ for everything above that, plus a daily access charge. A Quebec house with electric heat is already past 40 kWh a day in winter, so snow-melt energy is billed at the higher tier. That puts the 10 kW single-car strip at about $1.11 an hour, and a nine-hour event at about $10.03 (about $24.07 for the double driveway).
On Rate Flex D, energy used during a peak event costs 46.463¢ per kWh, about $4.65 an hour for the single-car system. Peak events fall on the coldest mornings and evenings, which is when snow-melt systems tend to run. If you're on Flex D, your controller needs to know about peak events.
Roof cable looks cheap by the hour. A 1.2 kW run costs about 12¢ an hour at Ontario off-peak and about 13¢ in Quebec. The cost comes from how long it runs. On an ambient thermostat, it can run around the clock: 28.8 kWh a day, or roughly 860 kWh over a month of sustained cold. At Ontario time-of-use prices, where round-the-clock running mixes off-, mid- and on-peak hours, that's roughly $110. On Quebec's Rate D it's about $96. That's for one month and one roofline. A snow-and-moisture controller is the difference between a running cost and a background drain.
How many hours a winter actually brings is a separate question, and this year's seasonal outlooks disagree about it.
No article can give you your bill. What it can give you is the formula and two honest worked examples:
kW × hours of operation × your price per kWh = energy cost
The prices below are the electricity commodity rate only. Delivery charges, regulatory charges, tax and any provincial rebate appear separately on your bill.
The Ontario Energy Board's current prices, in effect until October 31, 2026, set winter time-of-use rates at 9.8¢ per kWh off-peak, 15.7¢ mid-peak and 20.3¢ on-peak. The ultra-low overnight plan charges 3.9¢ from 11 p.m. to 7 a.m. but 39.1¢ on weekday evenings from 4 to 9 p.m. The OEB resets prices every November 1, and the 2026–27 prices hadn't been announced at the time of writing.
Applied to the worked systems, a 10 kW single-car strip costs about $0.98 an hour off-peak, $2.03 on-peak and $3.91 at the ultra-low-overnight plan's on-peak price. A nine-hour storm event (six hours of snowfall plus a three-hour hold-on) uses 90 kWh: about $8.82 off-peak or $18.27 on-peak. The same event on a 24 kW double driveway uses 216 kWh, about $21 off-peak or $44 on-peak.
On the ultra-low overnight plan, timing becomes a bigger factor than wattage. A snowfall that starts at 4 p.m. on a weekday costs ten times as much per kWh as the same snowfall at midnight.
Hydro-Québec's Rate D, effective April 1, 2026, charges 7.065¢ per kWh for the first 40 kWh a day and 11.142¢ for everything above that, plus a daily access charge. A Quebec house with electric heat is already past 40 kWh a day in winter, so snow-melt energy is billed at the higher tier. That puts the 10 kW single-car strip at about $1.11 an hour, and a nine-hour event at about $10.03 (about $24.07 for the double driveway).
On Rate Flex D, energy used during a peak event costs 46.463¢ per kWh, about $4.65 an hour for the single-car system. Peak events fall on the coldest mornings and evenings, which is when snow-melt systems tend to run. If you're on Flex D, your controller needs to know about peak events.
Roof cable looks cheap by the hour. A 1.2 kW run costs about 12¢ an hour at Ontario off-peak and about 13¢ in Quebec. The cost comes from how long it runs. On an ambient thermostat, it can run around the clock: 28.8 kWh a day, or roughly 860 kWh over a month of sustained cold. At Ontario time-of-use prices, where round-the-clock running mixes off-, mid- and on-peak hours, that's roughly $110. On Quebec's Rate D it's about $96. That's for one month and one roofline. A snow-and-moisture controller is the difference between a running cost and a background drain.
How many hours a winter actually brings is a separate question, and this year's seasonal outlooks disagree about it.
Most people start weighing these systems just before the first snow. For roof cable, that timing works. A planned circuit and controller can go in this fall. For a heated driveway, the calendar has mostly made the decision already.
Heated driveways go in with a new surface, because the code requires mats to be embedded at least 50 mm deep. New concrete has its own seasonal limits. Concrete Alberta advises against placing concrete pavement after September 30 unless proper cold-weather procedures are followed, and recommends keeping de-icing salts off new concrete for its first year. An October pour with buried heating cable is possible, but it's a cold-weather concrete job with an inspection to coordinate, not a routine one.
So for most readers this year, the realistic order is: confirm the service size this fall, get the load calculation done, and plan the driveway for spring alongside a resurfacing you were already planning.
Installed pricing is widely published, but the published ranges vary a lot. In September 2026, RenoQuotes listed electric snow melt at $18 to $28 per square foot installed and described a $1,500 to $4,500 service upgrade as normal.
A Greater Toronto installer quoted $24 to $55 per square foot, plus $2,000 to $3,000 for electrical work. Treat both as quotes, not benchmarks. A spread that wide tells you to get at least three quotes, each with a load calculation attached.
If a new surface is part of the plan anyway, the material choice and the heating decision belong in the same conversation:
Most people start weighing these systems just before the first snow. For roof cable, that timing works. A planned circuit and controller can go in this fall. For a heated driveway, the calendar has mostly made the decision already.
Heated driveways go in with a new surface, because the code requires mats to be embedded at least 50 mm deep. New concrete has its own seasonal limits. Concrete Alberta advises against placing concrete pavement after September 30 unless proper cold-weather procedures are followed, and recommends keeping de-icing salts off new concrete for its first year. An October pour with buried heating cable is possible, but it's a cold-weather concrete job with an inspection to coordinate, not a routine one.
So for most readers this year, the realistic order is: confirm the service size this fall, get the load calculation done, and plan the driveway for spring alongside a resurfacing you were already planning.
Installed pricing is widely published, but the published ranges vary a lot. In September 2026, RenoQuotes listed electric snow melt at $18 to $28 per square foot installed and described a $1,500 to $4,500 service upgrade as normal.
A Greater Toronto installer quoted $24 to $55 per square foot, plus $2,000 to $3,000 for electrical work. Treat both as quotes, not benchmarks. A spread that wide tells you to get at least three quotes, each with a load calculation attached.
If a new surface is part of the plan anyway, the material choice and the heating decision belong in the same conversation:
Here's the whole guide in one place. Draws assume 40 to 50 W per square foot for driveways and 5 W per foot constant-wattage (or self-regulating equivalent) for roof cable. Service fit is for the worked 150 m² gas-heated house above.
The reverse of the last column is just as useful. Neither system earns its place on a short, flat driveway that's easy to clear, or one a snow-clearing contract already handles. Neither earns it when the service upgrade isn't in the budget, because a system that can't run at full power during a storm isn't doing its job. And cable isn't the first step for ice dams in a house with an accessible attic that hasn't been air sealed. Fix the cause, watch one winter, then decide whether any eave still needs cable.
Ventilation works alongside air sealing in the attic. If you're planning attic work before deciding on cable, start here:
Attic Ventilation in Cold Climates: Why It Matters & How to Improve It
Here's the whole guide in one place. Draws assume 40 to 50 W per square foot for driveways and 5 W per foot constant-wattage (or self-regulating equivalent) for roof cable. Service fit is for the worked 150 m² gas-heated house above.
The reverse of the last column is just as useful. Neither system earns its place on a short, flat driveway that's easy to clear, or one a snow-clearing contract already handles. Neither earns it when the service upgrade isn't in the budget, because a system that can't run at full power during a storm isn't doing its job. And cable isn't the first step for ice dams in a house with an accessible attic that hasn't been air sealed. Fix the cause, watch one winter, then decide whether any eave still needs cable.
Ventilation works alongside air sealing in the attic. If you're planning attic work before deciding on cable, start here:
Attic Ventilation in Cold Climates: Why It Matters & How to Improve It
About the Author
Ryan is the founder of Homeowner.ca and a proud Canadian homeowner based in Guelph, Ontario. Over his 25-year career in digital publishing, he has focused on transforming complex information into clear, practical guidance that helps people make confident, well-informed decisions.
Most residential electric snow-melt mats are rated between 40 and 50 W per square foot at 240 volts. At 50 W, every 100 square feet adds 5 kW, about 21 A.
Sometimes, if it's small. Tire tracks (about 4 kW) usually fit a gas-heated house. A full single-car strip (about 10 kW) is borderline, and a double driveway (about 24 kW) equals the entire nominal capacity of a 100 A service. Your electrician's Rule 8-200 calculation decides.
The demand-factor relief in Section 62 is for space heating. Snow melt has no dedicated line in the Section 8 single-dwelling calculation, and many electricians count it at 100% because it runs continuously during storms. Your inspector has the final say.
The code's ground-fault protection for heating cable is set to prevent fires from arcing faults, not to protect people from shock, so it trips at a higher level (commonly 30 mA) than a 5 mA GFCI. Long cable runs on a standard GFCI often trip for no real reason.
No. Manufacturers describe the cable's job as keeping a drainage path open through the ice. The dam forms because heat escaping into the attic melts snow on the roof, so air sealing and ventilation address the cause.
An ambient thermostat turns the cable on whenever it's below freezing, which can mean weeks of constant running. A controller that senses moisture in the gutter and falling snow runs it only when there's ice to melt.
Yes, in all four provinces covered here. Ontario requires an ESA notification before work starts, BC requires approval before circuits are energized, Alberta municipalities issue electrical permits, and Quebec requires a declaration to the Régie du bâtiment du Québec for work that adds cable.
Not on top of it. The code requires outdoor heating cable to be embedded at least 50 mm below the finished surface, so mats go in with new concrete, a new asphalt base or a new paver bedding.
Multiply the system's kW by the hours it runs and by your per-kWh price. A 10 kW system costs about $1 an hour at Ontario off-peak or on Quebec's Rate D, before delivery and tax. Controls that limit run time matter more than the rate.
Find your service size on the main breaker, ask an electrician for a load calculation, and get the attic air sealed if ice dams are the concern. The Canadian Snow-Ready Roof guide covers the rest of a fall roof check.
