Which electric underfloor heating system is the best in the UK?

A cold bathroom floor in a London flat or a conservatory that never warms up is usually what sends people looking at electric underfloor heating, and then the brand names start to swamp the decision. Drainplumb handles underfloor heating installation and repair across Greater London, and the right system is settled by your floor, not a label.

Drainplumb is a plumbing and drainage business covering London and the towns around it. If you need underfloor heating repair in City of Westminster, we cover that too, and you describe the job at no charge before a written price arrives.

Get a quick quote from Drainplumb for underfloor heating anywhere in Greater London, or call 07401 062636 and describe the job.

Which electric underfloor heating system is the best in the UK?

The best electric underfloor heating system in the UK is the one that matches your floor build-up, room size and floor covering: for most existing homes that means heating mats over insulation boards, run from a programmable thermostat with a floor sensor. Loose cable and foil systems win in specific situations.

Mistakes people make when picking a system

The commonest mistake is hunting for a single winner by brand. Every mat or cable that meets the standards turns heat into warmth at the same rate: nearly all the electricity you pay for becomes heat. What differs is how the element is laid, how it copes with your floor, and how well the controls are matched to the room. A good product fitted badly beats nothing, and a poor fit ruins a good product.

The second mistake is skipping insulation. Without insulation boards under the heating, a lot of the warmth goes down into the slab or the joists, the heat-up time stretches and the running bill climbs. Thermal resistance of the floor covering matters from above in the same way: thick carpet and underlay slow the heat badly.

Third, people assume electric is cheap all round. Electric systems are generally cheaper to install than wet systems but dearer to run, particularly over a large area. That is why they suit bathrooms, kitchens, conservatories and single rooms better than a whole house. We state no running-cost figure here because the electricity price per kWh moves, and a number would be out of date soon.

Fourth, laying the element before testing it. The resistance should be checked before, during and after the floor goes down, because a nail or a trowel can ruin a cable that nobody can reach later.

The factors that decide the answer for your home

Here is how the three main types compare in practice:

• Heating mats: cable pre-fixed to a mesh, rolled out over the floor. Quickest to lay in regular rooms, suited to tiles and stone, and the usual choice for bathrooms.
• Loose cable: a cable you space out yourself. It copes with awkward shapes, alcoves and rooms full of fixtures, and the spacing lets you adjust output. It takes longer to fit.
• Foil heating systems: thin elements under laminate or floating floors, with little added height. Good where floor level is tight, less so under tile.

Then the home decides the rest. Room size and layout set which type is practical. The subfloor matters: concrete, timber joists and old boards all need different preparation. Floor covering matters: tile, stone and engineered wood carry heat well, while carpet and thick underlay do not. Output is often quoted around 150W/m² for rooms with decent insulation, and the right figure depends on how much heat the room loses.

Whole-home against single-room is the big question. If you want every room warmed, a wet system fed from a boiler or heat pump usually makes more sense than electric mats everywhere. If you want a warm bathroom floor or a comfortable kitchen, electric is hard to beat. Zoned controls, one thermostat per room, stop you heating spaces you are not using.

Rules and safety points that apply

Electrical work in a home is covered by Part P of the Building Regulations, so the connection to the supply must be done by someone competent to do it and the work must be notified or certified as the rules require. Bathrooms add extra requirements: the system should sit behind appropriate protection, typically a residual current device, and the wiring has to respect the zones around baths and showers.

Floor temperature limits matter too, especially under timber, where overheating can damage the boards. A floor temperature sensor linked to the thermostat is how that limit is held, and under wood it is the control you want. Never lay a heating element under fixed furniture such as a bath or a kitchen unit, because trapped heat can cook the element.

Customers also come to us for underfloor heating in Islington, where older flats and conversions bring joist floors and tight floor heights, and those decide the system far more than any brand name.

Signs that tell you where you stand

If the room is a bathroom, kitchen or conservatory and you want a warm floor rather than a main heat source, electric mats are almost certainly your answer. If the room has a lot of odd corners, think loose cable. If the floor build-up has almost no spare height and a floating floor going on top, foil is worth a look.

If you already have an electric system, the symptoms of trouble are plain: a cold patch where the rest is warm, a thermostat showing an error, a trip on the circuit, or a reading that no longer matches the original resistance. A cold patch on a finished floor usually means a damaged cable, and finding it means testing before anything is lifted. The consequence of a failure under a finished floor is the strongest argument for testing during installation and for careful laying, because the repair is far more disruptive than the fitting.

What you can do yourself and what needs a professional

You can safely do the following yourself: choose the thermostat, set the schedule, and take a look at the floor covering you plan to lay. A smart wi-fi thermostat is a sensible upgrade for control, and programming it is within anyone's reach. Preparing the floor, clearing it, and sweeping it are also fair jobs for an owner.

The fixed electrical connection is not a do-it-yourself job. Wiring to the consumer unit, protection, and the testing and certification belong to somebody who can do and sign off electrical work. Laying the element on the floor is practical for many people but easy to get wrong, and damage under a finished floor is expensive. Tiling over a system and fixing it into screed should also be treated carefully.

If your system is wet, linked to a boiler and manifold, that is a plumber's job entirely. We handle both wet and electric, installation and repair, across Greater London and the towns around it.

How it works in practice, step by step

• Survey: measure the room, note the fixtures, check the subfloor and the floor covering planned.
• Prepare the floor: make it flat, clean and dry, then fix insulation boards where the build-up allows.
• Test the element: record the resistance on the roll before it goes down.
• Lay the mat or cable: keep it clear of walls and fixtures, and place the floor sensor in a conduit between the runs.
• Test again: check the resistance after laying and again after the adhesive or screed.
• Connect and commission: a competent electrician makes the final connection to the thermostat, and the system is heated up gradually.
• Lay the finish: tile, wood or other floor covering goes on only after the tests pass.

The job can take from a day to a few days depending on drying times for adhesive or screed. If you are wondering whether the whole thing will cost a lot, we explain what drives it in our piece on whether does underfloor heating cost a lot is the right question to ask. The honest answer there is that it depends on room size, floor condition and what has to come up first, and you get a written price after we have heard the details.