Underfloor Heating: All Your Questions Answered

what is underfloor heating

Underfloor heating, or under tile heating specifically, is an electric cable system that sits directly under your tiled floor, and heats up under the control of a thermostat. It can be used to either take the chill off the tiles or can be laid to form a primary heat source for a room. Scroll down for lots of FAQs about underfloor heating, answered by our tiling expert, the Tile Guru!


what is underfloor heating


How to use underfloor heating

Electric underfloor heating is controlled by a thermostat. The thermostat will regulate the floor to the required temperature set by the user. As well as the temperature, you also have the option to program the times the heating comes on and switches off, depending on the thermostat you purchase.




How effective is underfloor heating?

Over standard central heating radiators, Underfloor heating gives you even heat distribution through the room, comfortable and adjustable room temperature, eliminates draughts and cold areas, and a warm floor for additional comfort.



How expensive is underfloor heating?

Heating mats start from as little as £29.95 and thermostats from £79.95. In addition there is the option of insulation, which will make the heating more efficient and drastically reduce the running cost.


How much does underfloor heating cost to run?

Based on current average electric price (14p per/kWh), a 150W electric underfloor heating system will cost approximately 2.1p per m2 per hour, when installed in conjunction with insulation. As a rule of thumb a 150W/m2 EUFH system should cost between £12 – £14 per m2 , per year when installed in a well insulated environment.




How thick is underfloor heating?

The cables are only 3.5mm thick so the impact on floor height can be minimal. Low profile insulation can also be supplied at thickness’s from 6mm upwards.


How much underfloor heating do I need?

If you are intending to use the system as the room’s primary heat source (recommended), you would need a mat that covers 80% of the total floor area. We are supplying room kits that give you enough insulation to cover the whole room (for height and efficiency) and a heating mat that will cover the correct area of 80%.


Which tiles for underfloor heating?

Almost any type of tile can be used with it. Ceramic, porcelain, natural stones including Slate, Marble, Limestone and Travertine. Even our white and black quartz can be used in conjunction with the 150W mats. With an additional 10mm layer of self levelling compound encasing the 150W cables, you can also use most soft flooring types, including wood, laminate, carpet and vinyl flooring. Whatever flooring type you decide, please contact your flooring manufacturer for advise on suitability.




Which electric heating system should I choose?

The 150w is intended as a primary heat source in areas such as lounges, kitchens and bedrooms. Although it offers a lower output, it is more efficient and has a lower running cost when used over prolonged periods. The 200w system can be used in kitchens, conservatories and bathrooms, if you will only ever need the heating for shorter periods. To take this into account, the 200w systems benefit from reduce heat-up times.


Why is underfloor heating efficient?

Limitations of radiators:

  • Heat rises from radiator to ceiling
  • Heat loss through the roof
  • Creates draughts and uneven heat
  • Cold floors and hot heads

Benefits of Underfloor heating:

  • Even heat spread through the room
  • Comfortable room temperature
  • No draughts or cold areas
  • Warm floors and increased comfortIf you feel that radiators are sufficient for heating the room, the underfloor heating can be used alongside for taking the chill off the tiles, however bare in mind the cost of running two systems at once. The underfloor heating is more than capable of being a sole source of heating for any room.




What temperature should underfloor heating run at?

The system will run at whatever temperature you require. The thermostat will regulate the output of the heating accordingly to achieve the set temperature as stipulated by the used. If the floor has reached its optimal temperature, the power output will be automatically reduce so that the floor can “simmer” and remain constant. For safety, the thermostat has a temperature limit of 30oC.




When should I install underfloor heating?

Because of the versatility and ease of installation, there is no right or wrong time to install it. But fixing in it in Spring, Summer or Autumn, will see you well prepared for the colder wintery weather.


When to use underfloor heating

It is down to personal preference and routine of the household as to when these heating systems are used. For the average family, it will be programmed to come on for an hour or two in the morning for when you get up, and then run again in the evening when everyone is home from work. But the thermostats can be fully programmed to suit the needs of anyone who wishes to benefit from it. This can be adjusted for seasons of a colder temperature.


Underfloor heating for large areas

Underfloor heating can be laid in any area regardless of size. The individual mats can be as large as 24 sqm. For larger areas, either multiple thermostats can be used in a single room, or a devise called a “contactor snubber” can be used to regulate multiple mats via a single thermostat.


What if the underfloor heating is not working?

The heating we supply comes with a manufacturers guarantee that can be registered upon installation. If you have any issues with the heating system not working for any reason, please contact them and they will discuss the possible fixes.


Underfloor heating with timber joists and wooden floors

To install over joists, we’d recommend that a stable surface such as 18mm plywood is screwed over the joists at 300mm intervals. Existing floor boards may require additional screws to ensure the deflection is minimised. The cement coated installation on top will add a bit of extra stability and provide much better insulation. The heating mat can then be laid and tiled over to suit.


Browse our selection of underfloor heating and add some warmth into your home this season.


We hope that answers your questions! If you have any other questions about your project, visit our Help Centre – it’s the ‘Wikipedia’ of tiling queries.



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