How to Install Underfloor Heating Under Wood or Laminate Floors

This guide covers the whole job: planning and measuring, preparing the subfloor, laying the ribbon, choosing an underlay that works with underfloor heating, and fitting the boards over the top. Planning and laying are DIY-friendly. The final electrical connection is not. A qualified electrician must make it, in line with Part P of the Building Regulations and BS 7671.

EkoBuild is an AHT amorphous ribbon specialist based in Flint, North Wales. The system is fitted in over 100 UK homes and carries a 15-year warranty, honoured directly by the UK importer. Stuck at any point? Call us on 07883 298944.

Tools and materials checklist

• AHT ribbon heating mats, 0.5m or 1m wide, to match your plan
• WiFi touchscreen thermostat with floor probe
• Therm-All insulation packs (each covers 10m2)
• Underlay marked as suitable for underfloor heating (low tog)
• Your chosen wood or laminate flooring, rated for underfloor heating
• Tape measure, pencil and paper (or use the room designer tool)
• Strong tape for fixing insulation and mats in place
• Knife or scissors for trimming insulation (never the heating ribbon)
• Vacuum and brush for subfloor prep
• Flooring spacers for the perimeter expansion gap
• A qualified electrician for testing and the final connection

Planning and measuring your room

Get the planning right and the rest of the job is straightforward. Measure the room, sketch it on paper, and mark anything fixed: kitchen units, built-in wardrobes, a hearth. Do not plan heating under fixed units or furniture that sits flat to the floor. Heat needs to escape upwards. Keep the ribbon clear of the perimeter too, where your expansion gap will sit.

Next, decide what the heating is for. If it is comfort heating to take the chill off, cover the areas you walk on and sit in. If it is your primary heat source, you need a minimum of 70% floor coverage for the room to reach temperature on cold days.

Then match mats to your plan. The ribbon comes in two widths. 0.5m wide mats cost £45 per square metre and come in lengths from 1m to 7m. 1m wide mats cost £65 per square metre and come in lengths from 1m to 3.5m. Both output 150W per square metre. Combine widths and lengths to fill the space, because the ribbon must never be cut to fit.

If you would rather not do the maths, use our room designer. Draw your room and it gives you the exact ribbon layout and price.

What you need

The full kit list is above. The short version: ribbon mats to match your plan, Therm-All insulation to push the heat up into the room instead of down into the subfloor, the WiFi touchscreen thermostat with a floor probe, and an underlay marked as suitable for underfloor heating. Everything else is basic kit you probably already own. Orders over £150 ship free anywhere in the UK.

Step-by-step installation

Here is the full sequence for a floating wood or laminate floor. Take your time on the first three steps. A clean, flat, insulated base makes everything after it easier.

1. Plan your layout. Measure the room and sketch where each mat will go. Keep heating away from fixed furniture and the perimeter expansion gap. For primary heating, plan at least 70% floor coverage.
2. Prepare the subfloor. Clear the room and vacuum the subfloor. It needs to be clean, dry and flat, with no protruding nails, screws or sharp debris that could damage the ribbon.
3. Lay the insulation. Cover the heated area with Therm-All insulation and tape the joints. Insulation directs the heat up into the room instead of down into the subfloor.
4. Roll out the ribbon mats. Position each mat following your plan and tape it down flat. Never cut, fold or overlap the heating ribbon.
5. Route the leads and floor probe. Run the connection leads towards the thermostat position on the wall. Place the floor probe within the heated area, following the instructions supplied with the thermostat.
6. Have the mats tested. Ask your electrician to test each mat before anything covers it. Faults are cheap to fix now and expensive to fix under a finished floor.
7. Lay an underlay rated for underfloor heating. Choose an underlay marked as suitable for electric underfloor heating, with a low tog rating so heat passes through. Do not use thick insulating underlay.
8. Fit the wood or laminate boards. Float the boards over the underlay in the normal way, leaving the expansion gap your flooring manufacturer specifies around the perimeter. Never nail or screw through the floor into the heated area.
9. Let your electrician make the final connection. A qualified electrician must connect the mats and thermostat to the mains, in line with Part P of the Building Regulations and BS 7671. Laying the system is DIY-friendly. The electrics are not.
10. Heat up gradually. Once signed off, run the system at a low temperature first and raise it gradually over several days. Set the thermostat floor limit to match your flooring manufacturer's maximum surface temperature.

One rule sits above all of these: never cut, fold or overlap the heating ribbon. If a mat does not fit, change the layout or the mat size, not the mat.

Advice for wood and laminate floors

Wood and laminate behave differently over heat, so a few checks are worth making before you buy boards.

• Check the boards are rated for underfloor heating. Most laminate and engineered wood is, and the packaging or datasheet will say so. If it does not say, ask the manufacturer before you buy.
• Engineered wood is the safer choice over solid wood. Its layered construction copes better with temperature changes. If you want solid wood, only use boards the manufacturer confirms are suitable for underfloor heating.
• Respect the maximum floor surface temperature. Flooring manufacturers state a temperature limit for their boards. Set the floor limit on the thermostat to match it, using the floor probe. That is exactly what the probe is there for.
• Acclimatise the boards. Leave the packs in the room before fitting, for as long as the flooring manufacturer directs, so the boards adjust to the room's temperature and humidity.
• Leave proper expansion gaps. Wood and laminate move with heat and humidity. Leave the perimeter gap your manufacturer specifies, use spacers while fitting, and cover the gap with skirting or beading.
• Go easy on thick rugs. A heavy rug over a heated area traps warmth beneath it. Keep rugs thin, or keep them off the heated zones.

Common mistakes to avoid

• Cutting the ribbon to fit. Never do this. Change the mat length or width instead. The room designer removes this problem at the planning stage.
• Using standard insulating underlay. A thick underlay blocks the heat you are paying for. Use one marked for underfloor heating with a low tog rating.
• Skipping the insulation underneath. Without it, a share of your heat warms the subfloor instead of the room, and running costs climb.
• Heating under fixed furniture. Trapped heat helps nobody. Plan around units and flat-bottomed furniture.
• No test before the boards go down. Always have the mats tested while you can still get at them.
• Full heat on day one. Bring the temperature up gradually over several days and stay within your flooring manufacturer's limits.
• DIY-ing the mains connection. The final connection is a job for a qualified electrician under Part P and BS 7671. No exceptions.

What it costs: a worked example

Here is a real example priced from our shop, for a 4m x 5m lounge (20m2) using the ribbon as the primary heat source.

• Primary heating needs at least 70% coverage: 20m2 x 0.7 = 14m2 of ribbon
• 14m2 of 0.5m wide ribbon at £45 per m2 = £630
• Therm-All insulation, two 10m2 packs at £53.50 each = £107
• WiFi touchscreen thermostat = £89.99

Total: £826.99, with free UK delivery because the order is over £150. Add your electrician's charge for testing and the final connection, which varies by area, so get a local quote. A smaller room used for comfort heating costs much less, because you only cover the areas you use. Doing a bathroom instead? See the Bathroom Complete Kit at £299.

Next steps

Ready to plan your room? Draw it in the room designer and you get the exact ribbon layout and price straight away. Browse the full range in the shop, or start with our electric underfloor heating guide if you are still weighing up options. Wondering whether it can replace your radiators? Read electric underfloor heating as primary heat, and see underfloor heating with no screed for why no self-leveller is needed. If you would rather talk it through first, call us on 07883 298944. We are happy to help you plan the room before you spend a penny.

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