Quick estimate mode — for thermostat savings, months in use and full cost breakdown: Full calculator →

Underfloor Heating Cost — Quick Estimate

Enter your floor area, heating type and electricity rate to get estimated daily, monthly and seasonal running costs.

Your Floor & Usage

The area the mat, cable or foil actually covers.
Scheduled window — not the same as actual run time if you have a thermostat.
Check your energy bill for the unit rate.

Estimated Cost

Daily
/day
Monthly
/month
Season (6 mo)
6 months

Estimates assume continuous operation. A thermostat typically reduces effective run time by around 30%. Actual costs vary with insulation, floor construction and thermostat settings.

Need thermostat savings, custom months in use and a full cost breakdown?
Full calculator covers heating cables, mats and foil with seasonal and annual projections.
Full Calculator →
How to estimate underfloor heating running costs

The formula

Daily cost = (floor area × W/m²) ÷ 1000 × hours per day × electricity price. A 10 m² floor at 120 W/m² draws 1.2 kW. At 8 hours per day and $0.28/kWh, that is 9.6 kWh × $0.28 = $2.69 per day.

Wattage by heating type

Heating foil runs at around 100 W/m², low-output mats at 120 W/m², standard mats at 150 W/m² and cables at 160 W/m². Lower wattage means lower running costs per square metre, but also a slower warm-up time.

Why a thermostat matters

These estimates assume the system runs continuously for the full scheduled hours. A programmable thermostat cycles the heating on and off to hold the target temperature, typically reducing effective run time by around 30%. Use the full calculator to include this saving.

Pro tip: The area input should reflect the area the mat or cable actually covers — not the full room size. Around bathroom fixtures and under furniture, the heated area is often 10–20% less than the total floor area.
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