Carbon infrared heating film is the thinnest and quickest electric underfloor heating you can fit under a floating floor. This guide covers what it is, which floors it suits, what goes into a system and what it costs to buy and run, so you know exactly what you need before you order.
What is carbon heating film?
The film is a thin polyester sheet, about 0.4 mm thick, with strips of carbon printed on it. When power flows through the carbon it warms up evenly across the whole strip. Copper bus bars run along both edges and carry the power.
Because the heated area is so large, the film does not need to get very hot. The floor is normally kept to around 27 °C or less by the thermostat's floor sensor, which is comfortable to stand on and kind to wooden floors.
Which floors can go on top?
- Yes: laminate and engineered wood laid as a floating floor, straight on top of the film and insulation.
- Yes, with a board: carpet and soft vinyl need a firm layer over the film. Use the ECOMAX-DUO Dual Board Overlay System between the film and the floor covering.
- No: tiles, stone and anything laid in adhesive or screed. Film is also not suitable for bathrooms or wet rooms. For those rooms, ask us what to use instead.
Not sure about your floor? Ask us and we will tell you before you buy.
What goes into a film system
- Insulation board. Our XPS Thermal Insulation Board is 6 mm thick. It stops heat being lost into the subfloor, protects the film from the subfloor, and acts as the underlay for your new floor, so you do not need a separate underlay.
- The film. Carbon Infrared Underfloor Heating Film comes in 0.5 m, 0.8 m and 1 m widths and in 80, 110 or 130 W/m². Most homes use 130 W/m². Use wider film for open rooms and narrower film for awkward shapes.
- Connections. Crimps, insulation for the cut ends, and cold tails to take power to the thermostat.
- Vapour barrier. A polyester sheet laid over the film. Together with double-insulated cold tails, it makes the installation Class II.
- Thermostat with a floor sensor. This keeps the floor at a safe temperature and lets you set heating times. See our thermostat guide.
How it goes in, step by step
The easiest way to get everything in one box is a Kit PRO. The Kit PRO with 1 m film includes the film, crimps, cold tails, tapes and vapour barrier for a 10, 15, 20 or 25 m² room. The Kit PRO with 50 cm film suits smaller or narrower rooms from 5 m².
What does it cost?
Prices on our website in October 2026:
- Film on its own: from £19.91 per m² (1 m wide film).
- Kit PRO with 50 cm film: from £179 for a 5 m² room.
- Kit PRO with 1 m film: £269 for 10 m², up to £649 for 25 m², which is about £26 per m².
- Insulation board: £35.76 for 5 m², about £7.15 per m².
Add a thermostat and, if you are carpeting, the ECOMAX-DUO board. Kits cost less than buying the same parts separately.
What does it cost to run?
A 10 m² room with 130 W/m² film draws 1.3 kW at full power. At the October 2026 price cap rate of 26.32p per kWh, that is about 34p an hour while the film is fully on.
Once the room is warm, the thermostat switches the film on and off to hold the temperature, so it is not on all the time. How much depends on insulation, how warm you like the room and the weather. Our heating calculator gives an estimate for your own room.
Who installs it?
Laying the insulation, film and floor is a careful DIY or flooring job. The electrical connection to the mains and the thermostat must be done by a qualified electrician. If you would like it fitted, our installation partner Standard Electrical Services can quote for the work.
Why film rather than a heating mat?
- It is very thin, so the floor height hardly changes.
- It heats a large surface evenly, so it runs at a lower temperature than cable.
- It goes straight under a floating floor, with no adhesive or screed.
- The carbon film is expected to last up to 50 years.
Get the right kit first time
Send us your room size and floor type and we will tell you which kit and thermostat you need, usually within one working day. Get a free quote, or try the heating calculator.