For a 10m² room, running flat out at full power, the maximum is 29p an hour at 28p per kWh, used as a worked example. That is the ceiling, not the bill. The thermostat cycles the heating off once the room reaches temperature, so the real figure is a fraction of it.
The calculation, in full
Take a 10m² room as the example.
When the Ribbon is being designed as the primary heat source we normally cover at least 70% of the available floor, subject to what the room actually needs. That gives 7m², which is 70% of a 10m² room.
The Ribbon produces 150W per m². Seven square metres at that output is 1,050 watts, or 1.05 kilowatts.
At 28p per kWh, used as a worked example, running continuously at full power for one hour costs 29p an hour.
That is the maximum hourly consumption for this example. It is not what you will pay every hour, and anyone quoting it as the running cost is quoting you the ceiling.
Why you never actually pay that
The thermostat only calls for heat when the room needs it.
Say you heat the room for an hour before work and three hours after you get home. That is a four-hour schedule, but it is not four hours of continuous electricity.
If the room is already at the temperature you set, the heating does not come on at all, and for that period it costs nothing. If you set it higher, the system draws power to bring the room up, then switches off once it gets there and cycles on and off to hold it.
In an average home the Ribbon draws full power for about 25% of each active hour. In a well insulated one it is nearer 7 to 10% in a well-insulated (EPC A-B) home.
What that comes to in practice
| Room | A 10m² room |
| Heated area at at least 70% coverage | 7m², which is 70% of a 10m² room |
| Load | 1,050 watts, or 1.05 kilowatts |
| Electricity price used | 28p per kWh, used as a worked example |
| Maximum, flat out for an hour | 29p an hour |
| Typical hour at a 25% duty cycle | Just over 7p for that hour |
| A four-hour schedule at that duty cycle | Around 29p for the day |
| Four hours flat out, the ceiling | About £1.18 |
| A 12m² room, average home | Around 50p a day in an average home |
| Certified to | Certified to EN 60335-2-96, the safety standard for flexible sheet heating elements for room heating, plus EN 60335-1 and EN 62233. Class II, double insulated. UL Listed for the US and Canada under UL 1693 and CSA C22.2 No. 217 for radiant space heating, certificate 20130417-E349312, and certified by Nemko under certificate P15220551 |
Work out your own
The formula is simple enough to do on your phone. Take your heated floor area, times 150 watts per square metre, times your electricity price. That gives the maximum hourly cost.
Then apply a duty cycle. About 25% of each active hour in an average home, nearer 7 to 10% in a well-insulated (EPC A-B) home.
We are deliberately not publishing a single whole-house figure. It depends far too much on the individual property to be honest about, and a number that is wrong for your house is worse than no number at all. Per room, with the working shown, is the useful version.
Across the year
In summer it may not run at all, in spring and autumn only occasionally, and on the coldest winter days it will run for longer.
A well insulated room holds its heat longer than a poorly insulated one, so the thermostat calls for heat less often. That is why insulation and heat retention matter just as much as the price of electricity.
Solar panels and battery storage
The Ribbon runs on electricity, which means it can run on electricity you generated yourself. You cannot make your own gas.
During daylight, solar can supply the heating and cut what you buy from the grid. But most people need heat early morning and evening, when solar generation is low. A battery bridges that gap, and on the right tariff it can also charge on cheaper off-peak power.
Solar electricity is not free, the equipment has a cost and exported power has a value, but using your own generated or stored energy cuts how much heating electricity you buy at the full grid rate.
On payback, 5 to 10 years on the capital cost. That is unusual for something you buy for a house.
Is it cheaper than gas?
Here is the honest answer, and it is not the one you would expect a heating company to give.
Electricity costs more per unit than gas on a standard tariff, so it would be misleading to say electric is automatically cheaper. The comparison that matters is room-by-room control, fast response, no slab to heat, and solar, battery or off-peak on top.
Whether it works out cheaper in your house depends on how the house is built and how you live in it. That is why every job gets tested on site rather than quoted off a table.
Full transcript
This is what Russell says in the video, in full. It is published so you can read it rather than watch it, and so search engines and AI assistants can read it too.
How much does electric underfloor heating actually cost to run?
For a 10-square-metre room using our ribbon underfloor heating, the maximum cost would be approximately 29 pence per hour, based on an electricity price of 28 pence per kilowatt-hour.
But that does not mean it will cost 29 pence for every hour that your heating is switched on.
The thermostat, your insulation, your chosen temperature and whether you have solar panels or battery storage all affect what you actually pay.
I'm Russell White from Eko Build. I've spent 30 years working in contract flooring, 25 years specialising in underfloor heating and 20 years working with renewable energy.
I've installed and assessed water, cable and ribbon underfloor heating, as well as solar panels, heat pumps, biomass boilers and wind turbines. I've also helped develop products, rather than simply fitting what was already available.
Twenty years ago, I brought that experience together when I built my own eco home using waste pallet blocks, solar power, wind turbines, heat recovery, biomass heating and electric underfloor heating.
Living with and maintaining these technologies taught me that making something work is only half the job. It also needs to be practical to install, control, service and repair.
That experience ultimately led me to ribbon underfloor heating, and I'm now sharing what I've learned to help homeowners make a properly informed decision.
Let's use a 10-square-metre room as a simple example.
When ribbon underfloor heating is being designed as the primary heat source, we would normally aim to cover at least 70% of the available floor area, subject to the heating requirements of the room.
Seventy per cent of a 10-square-metre room gives us seven square metres of heating.
This ribbon produces 150 watts per square metre.
Seven square metres multiplied by 150 watts gives us 1,050 watts, or 1.05 kilowatts.
At an example electricity price of 28 pence per kilowatt-hour, running the system continuously at full power for one hour would cost 29.4 pence.
We can round that to approximately 29 pence per hour.
That is the maximum hourly consumption for this example. It is not automatically the amount you will pay every hour.
The thermostat controls the room temperature and only calls for heat when it is required.
Let's say you heat the room for one hour before work and three hours after arriving home. That creates a four-hour heating schedule, but it does not necessarily mean four hours of continuous electricity consumption.
If the room is already at 18 degrees and your thermostat is set to 18, the heating does not need to come on. During that time, its running cost is zero.
If you set the thermostat to 21 degrees, the system must raise the temperature by three degrees. It will initially draw power to warm the room, but once 21 degrees is reached, the thermostat switches the heating off.
It then cycles the heating on and off as required to maintain that temperature.
That thermostat control is an important part of using ribbon underfloor heating as a practical primary heating system.
For example, if our 1.05-kilowatt system only needs to draw full power for 15 minutes during a particular hour, it would consume approximately 0.26 kilowatt-hours.
At 28 pence per kilowatt-hour, that would cost just over seven pence for that hour.
That is only an example of a 25% duty cycle. It is not a guaranteed running cost.
During a four-hour heating schedule at that average duty cycle, this room would use approximately 1.05 kilowatt-hours, costing around 29 pence for the day.
If it ran continuously at full power for all four hours, the maximum would be approximately GBP 1.18.
The ribbon itself begins producing heat very quickly, typically within around three minutes.
As a general rule of thumb from our experience, you may begin noticing warmth through carpet after approximately five minutes. Wood, laminate or stone may take around 15 to 20 minutes.
Those are approximate observations, not guaranteed heating times. The insulation, subfloor, flooring product and starting room temperature will all make a difference.
It is also important to understand that this is when warmth begins coming through the floor. It does not mean the entire room will reach 21 degrees in five minutes.
In summer, the heating may not operate at all.
During spring and autumn, it may only operate occasionally. On the coldest winter days, it will naturally need to run for longer.
A well-insulated room will normally retain heat for longer than a poorly insulated room, reducing how frequently the thermostat needs to call for more heat.
That is why insulation and heat retention are just as important as the price of electricity.
Ribbon underfloor heating can also work particularly well alongside solar panels and battery storage because it is powered directly by electricity.
During daylight hours, electricity generated by your solar panels can supply the heating system and reduce the amount purchased from the grid.
However, many people need the most heat early in the morning and during the evening, when solar generation is lower.
Battery storage helps bridge that gap. Surplus solar electricity generated during the day can be stored and used for heating later.
Depending on your electricity tariff, a battery may also be charged with cheaper off-peak electricity and used when grid prices are higher.
Solar electricity is not completely free because the equipment has an installation cost, and exported electricity can have a value. But using your own generated or stored energy can significantly reduce how much heating electricity you purchase at the full grid rate.
But data shows that solar and batteries have a pay back of your capital expenditure between 5-10 years. This being the first time you buy something for your home that actually gives you a pay back.
Electricity normally costs more per kilowatt-hour than gas, so it would be misleading to claim that electric heating is automatically cheaper in every house.
But the unit price is not the complete comparison.
Ribbon heating can be controlled room by room, responds quickly and heats where it is needed. When combined with suitable insulation, sensible schedules, solar generation and battery storage, the actual household running cost can be competitive with, and in the right property lower than, running a gas central-heating system.
The result depends on how the home is built and how the occupants use it.
So, how much does ribbon underfloor heating cost to run?
Start with the heated floor area, multiply it by 150 watts per square metre, and multiply that figure by your electricity price. That gives you the maximum hourly cost.
Your actual cost will depend on how frequently the thermostat calls for heat and how much electricity is supplied by the grid, solar panels or battery storage.
Get the number for your actual room
The free Room Designer works out the heated area, the coverage and the price for your room, so you are not working off an example.
Running cost FAQs
How much does electric underfloor heating cost to run per hour?
For a 10m² room at at least 70% coverage the load is 1,050 watts, or 1.05 kilowatts, so at 28p per kWh, used as a worked example the maximum is 29p an hour. In practice the thermostat cycles it off, and a typical hour is just over 7p for that hour.
What does a room cost to run per day?
Around 50p a day in an average home, on unit cost alone. A four-hour schedule in the a 10m² room example is around 29p for the day.
Is electric underfloor heating cheaper than gas?
Electricity costs more per unit than gas on a standard tariff, so it would be misleading to say electric is automatically cheaper. The comparison that matters is room-by-room control, fast response, no slab to heat, and solar, battery or off-peak on top.
Does it run all the time?
No. It draws full power for about 25% of each active hour, and nearer 7 to 10% in a well-insulated (EPC A-B) home. In summer it may not run at all, in spring and autumn only occasionally, and on the coldest winter days it will run for longer.
How does solar change it?
Solar electricity is not free, the equipment has a cost and exported power has a value, but using your own generated or stored energy cuts how much heating electricity you buy at the full grid rate. Most people need heat early morning and evening, when solar generation is low. A battery bridges that gap, and on the right tariff it can also charge on cheaper off-peak power. On capital cost, 5 to 10 years on the capital cost.
What electricity price are these figures based on?
28p per kWh, used as a worked example. Substitute your own unit rate: heated floor area, times 150 watts per square metre, times your electricity price. That gives the maximum hourly cost.