Electric underfloor heating or a heat pump? A 25-year cost comparison
In a small, well-insulated house, electric underfloor heating is usually cheaper over the entire service life, or a heat pump pays for itself only after more than 20 years. The larger the house and the higher its heat demand, the faster a heat pump gains the upper hand. Below we work through it step by step.
What exactly we compare
We compare two underfloor heating systems in a concrete screed: electrically powered WIS heating cables and an air-to-water heat pump with water underfloor heating. We calculate the total cost: purchase and installation at the start, then the energy bills and servicing every year.
- Electric underfloor heating: about PLN 160/m² incl. VAT with installation and thermostats, 100% efficiency, no servicing costs.
- Heat pump: about PLN 42,000 with installation, plumbing and plant-room equipment, plus water underfloor heating at about PLN 120/m²; seasonal efficiency SCOP 3.5; annual service PLN 600.
- Heat pump compressor replacement in year 12 (about PLN 9,000), and replacement of the whole heat pump in year 22 (about PLN 25,000), because replacing the compressor alone a second time no longer makes technical sense.
- Electricity price PLN 1.00/kWh incl. VAT, constant throughout. No subsidies, solar PV, inflation or time value of money.
These are the same assumptions used by the calculator on the home page. Enter the floor area and standard of your house there to see the chart for your own case.
Results for typical houses
A heat demand of 50 kWh/m²/year corresponds to an energy-efficient house. The amounts are the total cost after 25 years: investment plus all bills and servicing.
| House | Electric after 25 years | Heat pump after 25 years | Result |
|---|---|---|---|
| 70 m², 50 kWh/m²/year | PLN 98,700 | PLN 124,400 | electric cheaper by PLN 25,700, the heat pump never pays for itself |
| 80 m², 50 kWh/m²/year | PLN 112,800 | PLN 129,200 | electric cheaper by PLN 16,400, the heat pump never pays for itself |
| 100 m², 50 kWh/m²/year | PLN 141,000 | PLN 138,700 | the heat pump pays for itself only after 24 years |
| 120 m², 50 kWh/m²/year | PLN 169,200 | PLN 148,300 | heat pump cheaper from year 13 |
| 150 m², 50 kWh/m²/year | PLN 211,500 | PLN 162,600 | heat pump cheaper from year 8 |
| 100 m², 30 kWh/m²/year (passive) | PLN 91,000 | PLN 124,400 | electric cheaper by PLN 33,400 |
At the start, electric underfloor heating is cheaper by about PLN 36,000–39,000. The heat pump makes up this difference through lower bills, but in a small house the bills are so low that this takes a very long time or never happens at all.
Why a heat pump’s “payback year” can be misleading
A heat pump has parts that wear out. In our model the compressor is replaced in year 12 and the whole unit in year 22. Each of these expenses pushes back the point at which the heat pump really starts to pay off.
Example: in a 100 m² house with a demand of 50 kWh/m²/year, the heat pump becomes cheaper as early as year 16. But in year 22 it has to be replaced and electric heating is cheaper again. In the end, the heat pump pays for itself only in year 25.
In a 110 m² house the heat pump theoretically starts to pay for itself from year 14, but after the replacement in year 22 its advantage drops from PLN 23,300 to just PLN 1,600. The total costs of the two systems then practically even out.
The year in which a heat pump starts to pay for itself does not yet mean lasting cost-effectiveness. Look at the whole service life, not at the first point where the lines cross on the chart.
When a heat pump makes sense
We take an honest approach: in larger houses and at higher heat demand, the heat pump wins. At 150 m² and 50 kWh/m²/year it is cheaper from year 8, and in a 120 m² house with a demand of 100 kWh/m²/year as early as year 5. Electric underfloor heating as the only heat source makes sense above all in modern, well-insulated houses of a sensible size.
In older, poorly insulated buildings, electric underfloor heating is better treated as supplementary heating, for example in bathrooms.
Solar PV changes the sums
Installing heating mats or cables costs a fraction of the price of a heat pump with plumbing and plant-room equipment. You can invest the capital saved straight away in a solar PV system with energy storage, which lowers your heating bills. Smart thermostats with schedules let you heat when energy is cheapest.
What can we conclude from the comparison?
That heat pumps make no sense in well-insulated homes with a sensible floor area that reflects how we live today – under 100 m².
In such buildings, electric underfloor heating is ideal: it is inexpensive to buy, does not take up a room for a plant room and has no servicing costs. The relatively low running costs are acceptable to most users over a year, and with a properly sized solar PV system they can be close to zero.
Installing a heat pump with water underfloor heating in an energy-efficient home of under 80 m² is, from an engineering and financial point of view, a classic case of overkill – like buying a VIP gym membership paid 30 years in advance.
Check your house in the calculator
Frequently asked questions
How much does it cost to heat a 100 m² house with electricity?
At a demand of 50 kWh/m²/year (energy-efficient house) and a price of PLN 1.00/kWh incl. VAT, about PLN 5,000 a year. In a passive house (30 kWh/m²/year), about PLN 3,000. Solar PV can lower this cost.
After how many years does a heat pump pay for itself in a small house?
In a 70–80 m² house with a demand of 50 kWh/m²/year, a heat pump does not pay for itself within 25 years. In a 100 m² house it pays for itself only after 24 years, because the whole unit has to be replaced in year 22.
Can electric underfloor heating be the only source of heat?
Yes, in energy-efficient and passive houses. In older, poorly insulated buildings it is better treated as supplementary heating.
Does electric underfloor heating need servicing?
No. There is no compressor, no moving parts and no mandatory inspections. Warmup heating cables and mats come with a lifetime manufacturer’s warranty.
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Want to know how much it would cost in your home?
Check the estimated cost in the calculator or send an enquiry – we will prepare a quote with and without installation.