Electric floor heating is a thin cable or mat set into the bed under the tile and run by a thermostat with a floor sensor. It’s most worthwhile in bathrooms, front entries and basements over cold concrete. In Ontario the work needs an ESA notification and an inspection before the cable is covered, and it can only be added when the tile is being replaced.
What you’re actually installing
When people ask us about heated floors, they’re nearly always asking about electric systems. A heating cable, either loose or woven into a thin mat, is laid across the subfloor and embedded in the setting material just below the tile. Some uncoupling membranes have studs designed to hold the cable in neat runs, so the membrane and the heat go down as one layer.
The cable connects through a cold lead to a thermostat on the wall, and a floor sensor sits in the floor between two cable runs so the thermostat knows how warm the tile really is. Many floor-heating thermostats have ground-fault protection built in; Schluter’s DITRA-HEAT-E-R, for example, includes a Class A GFCI and comes with a floor sensor.
You never see any of it. Once the tile is set, the only visible part is the thermostat, which can be a simple dial-style control or a programmable or Wi-Fi model that warms the floor before you wake up and switches off when you leave for work.
Where heated floors earn their keep
Floor heating isn’t equally useful everywhere. These are the rooms where we see it make the biggest difference in a GTA winter.
| Room | Why it helps | What to plan |
|---|---|---|
| Main or ensuite bathroom | Tile is cold underfoot from November to March, and a warm floor dries bath mats and splashes faster. | Heat the open floor where you stand, not under the vanity, tub or toilet. Put the thermostat outside the wet zone, where you can reach it easily. |
| Front entry or mudroom | Snow and slush off boots dry much faster on a warm floor, and the area stops feeling like an extension of the porch. | Keep the heated area where people actually stand and take off boots. A door that seals well matters as much as the heat. |
| Basement bathroom or rec room over a slab | Concrete stays cold all winter, so a basement floor benefits more than almost any other room. | Ask about an insulating layer between the slab and the cable, since warming concrete from above wastes energy. Moisture in the slab must be dealt with first. |
| Kitchen | Warm tile where you stand at the sink and counters is a real comfort in an older, drafty house. | Cable never goes under cabinets or an island, so the layout follows the walkways. |
| Large open-plan rooms | Possible, but the electrical load and running cost climb with the area. | Compare with other ways of heating the space before committing to a large electric system. |
Floor warmth, not a furnace
Most electric systems sold for tile are floor-warming systems. Their job is to take the chill out of the surface you stand on, and in a small bathroom they can make the whole room feel warmer. They aren’t designed to replace the furnace or the main heating in a room, and a heated floor doesn’t fix a draft from a leaky window or an uninsulated exterior wall.
Running cost depends on the heated area, the cable’s wattage, how many hours a day the floor is on, the temperature you set and your electricity rate. The thermostat is where you control most of that. A schedule that warms the floor for an hour in the morning and again in the evening costs far less than a floor left on around the clock, and it’s the way most people end up using it.
If you’re weighing a heated floor against simply putting down a thick bath mat, think about how often you’ll use the room and how cold the floor gets. A basement bathroom on a slab in January is a very different experience from a main-floor powder room above a heated basement.
The electrical side in Ontario
This is the part not to cut corners on. Ontario’s Electrical Safety Authority says a notification of work must be filed for electric floor heating, whoever installs the heating cable, and the cable must be inspected before it’s covered. In a May 2025 safety notice, ESA described a fatal case in which a floor-heating mat had been installed without a notification, without its floor sensor, and was connected to the wrong voltage, so the floor overheated.
The same notice explains who does what. A flooring or tile installer can lay the heating cable or mat up to the first junction box for its cold lead, but the circuit wiring from the electrical panel must be done by a Licensed Electrical Contractor; ESA says a homeowner can legally do that wiring but doesn’t recommend it. The floor sensor has to be installed and connected, and the voltage supplied to the thermostat must match the voltage the mat or cable is rated for, since many thermostats accept both 120 and 240 volts and won’t correct a mismatch.
All of the equipment should carry a recognized Canadian approval mark such as CSA. In older GTA houses, an electrician may also need to check whether the panel has room for another circuit. That’s worth knowing early, because it can change the cost, so we ask for the panel to be looked at before we quote the floor.
Why it can’t go under the tile you already have
The cable lives in the layer directly under the tile, so there is no way to slide it in beneath an existing floor. Adding heat to a tiled room means taking the tile up, usually along with the layer it was set on, and starting again. That’s why the right moment for a heated floor is when you’re already renovating the bathroom, replacing the entry floor or finishing the basement.
If you’re planning one of those projects for this winter or next spring, decide about floor heating before the tile is ordered. The heated area, the thermostat location and the electrical circuit all have to be designed in, and the heating layer adds a little height to the floor, which affects thresholds and door bottoms. Our tile work page covers how we plan floor heights and transitions.
Wood, laminate and vinyl floors can sometimes be heated too, but only with systems and products whose manufacturers approve the combination. Tile and stone are the most forgiving partners for floor heat.
How a heated tile floor goes in
The order matters, because once the tile is down, mistakes are buried.
- Plan the heated area
We draw the floor and leave out the spots where cable doesn’t belong: under the vanity, tub, shower base, toilet and any built-in cabinets. The thermostat location and the sensor position go on the same drawing.
- Electrical rough-in and notification
The electrician runs the circuit and installs the box for the thermostat, and the ESA notification is filed before the work starts.
- Prepare the floor
The subfloor is checked for stiffness and flatness, and any insulating underlay or uncoupling membrane goes down as the system’s instructions require.
- Lay and test the cable
The cable or mat is laid in the planned pattern and its resistance is tested before, during and after embedding, as the manufacturer specifies, so a damaged cable is found while it can still be fixed.
- Inspection before covering
ESA inspects the heating cable before it’s covered. Only then does the tile go down.
- Tile, cure, then switch on
The tile is set and grouted, and the heat stays off until the setting materials have cured for the time their maker gives. Then the thermostat is connected and programmed.
What drives the cost
We don’t publish a separate price for floor heating, because it depends so much on the room. The main factors are the size of the heated area, whether it’s a mat or loose cable, the thermostat you choose, the electrical work needed to bring a new circuit to the room and any insulation or membrane under the cable. The tile itself, and the labour to set it, sit on top of that.
In a tile estimate, we price the heating as its own line, so you can see what it adds to the job. Our tile planning range is on the pricing page, and the heated floor is quoted once we’ve measured the room and the electrician has looked at the panel.
It’s also worth comparing the cost against how long you’ll be in the house. A heated floor in a bathroom you’ll use every winter morning for the next fifteen years is a very different decision from one in a guest bathroom that’s used twice a month.
Living with a heated entry floor through slush season
A warm entry floor dries the puddles that form under boots and helps the whole floor recover between storms. It doesn’t remove road salt, though. The white film that builds up on tile and grout in January comes off with plain water or a pH-neutral cleaner made for tile, and getting to it weekly keeps it from settling into the grout.
Rugs need a little thought. ESA warns that objects which significantly restrict airflow over a heated floor shouldn’t be left unattended on it unless the manufacturer allows it, so check the system’s instructions before laying a thick rubber-backed mat over the heated area. A boot tray on a non-heated strip by the door is often the simplest answer, and we can leave that strip out of the heated area when we lay out the cable.
Finally, set the entry floor’s schedule around the household. A floor that warms up an hour before the school run and again before everyone comes home in the evening does most of the work for a fraction of the running time.
Plan a warmer floor
If a bathroom, entry or basement project is coming up, these pages will help you plan it.
Frequently asked questions
Can I add heated floors under my existing tile?
No. The heating cable sits in the layer directly under the tile, so the existing tile, and usually the layer under it, has to come up. The best time to add floor heating is when the room is being renovated anyway.
Do heated floors need an electrical permit in Ontario?
Yes. ESA says a notification of work must be filed for electric floor heating, and the cable must be inspected before it’s covered. The circuit from the panel should be wired by a Licensed Electrical Contractor.
Can a heated floor heat the whole room?
Most electric systems under tile are designed to warm the floor, not to replace the main heating. In a small bathroom they can make the room feel noticeably warmer, but they won’t fix drafts or poor insulation.
Can I put a rug on a heated floor?
Check the system’s instructions first. ESA warns against leaving objects that significantly restrict airflow over a heated floor unattended unless the manufacturer allows it. A thin, breathable mat or a boot tray on an unheated strip is the safer choice.
Further information
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