The Complete Underfloor Heating Buying Guide

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The Complete Underfloor Heating Buying Guide

What is Underfloor Heating?

Underfloor Heating systems are a series of mats or wires installed underneath your flooring that essentially turns your floor into a radiator. An effective underfloor heating system is capable of replacing your radiators to deliver whole room heat. They can also be deployed to simply remove the chill from cold floors such as traditional stone floored kitchens & bathrooms but can also be installed beneath carpet or vinyl floorings for the same effect.

Which Underfloor Heating System Do I Need?

 Type of Flooring Subfloor System Needed
Ceramic/Natural Stone Screed & Concrete Wire, Mat, Inscreed
Carpet Screed & Concrete Inscreed, Foil Mat
Wood/Laminate Screed & Concrete Inscreed, Foil Mat
Ceramic/Natural Stone Suspended Timer Wire/Mat
Wood/Laminate Suspended Timber Foil Mat
Carpet Suspended Timber Foil Mat


What are the different types of underfloor heating and what do they do?


Ideal for refurbishment projects, mat systems can be installed without raising the floor height of the room and can be installed on screed/concrete and also suspended sub-floors. Suspended Timber floors are systems where an empty space sits between the concrete ground & timber floorboards to ensure floorboards are protected from damp. Mats are most often installed under tiled kitchen or bathroom floors.

Cable/Wire - Loose cable or in-screed cable

Wire Underfloor Heating systems can offer you greater flexibility than comparable mat installations. Some trade professional prefer to use cable as the added flexibility of the installation allow them to better tailor the heat to a specific part of the room and less in others e.g: if installing in an entrance hallway, the cable can be spaced 1 or 2 inches apart, instead of the standard 3, closer to the door to create a greater heat curtain where heat loss is more likely. Loose wire systems are suitable for use in regular and irregular shaped rooms.

Foil Mat A.K.A Sheet

Most often used under Vinyl or Carpet flooring as they can be directly installed under the floor finish without raising the floor level. If used under these flooring types, you must also use an accompanying overlay system and best suit a regular shaped room. Foil mat under carpet heating is one of the easiest ways to install underfloor heating as you only need to remove the carpet, install and then re lay.

Underfloor Heating FAQs

Do I need a qualified electrician to install?

Some of our underfloor heating brands offer “lifetime” warranties. To be eligible for this warranty, it must be registered and a professional electrician. Wiring rules state it has to be connected by a qualified electrician. 

What is Screed?

Similar in ingredients to concrete, Screed is used to level out a concrete sub-base floor and is used to cover the wires/cables that are used in Underfloor Heating Systems effectively diffusing & spreading the heat generated across the surface area of the floor.

How do I control the temperature of my Underfloor Heating System?

An accompanying Underfloor Heating thermostat must be fitted with all installations of underfloor heating systems. Depending on the brand, you can choose from a wide range of thermostats from simple button controls to WIFI and Google Nest/Home, Alexa enabled, smartphone connected thermostats to control your underfloor heating from anywhere. We also stock a range of thermostats that can give you advice on how to save energy and also work in the background to find you better energy tariffs to further reduce your bills! Please note: Nest thermostats only have a 3 amp rating so can only be used with smaller areas.

Will Underfloor Heating warm up the whole room?

YES! Underfloor heating systems can generate between 40°C and 65°C making the floor temperature between 23°C and 32°C on average making underfloor heating a genuine option for whole room heating. Depending on the room in which the system is deployed, your results may vary. In rooms with a large amount of heat loss, such as conservatories, your actual heat output will be reduced. If you’re unsure, give us a call and we can advise on which system would be best for your home.

Will my underfloor heating make my floor too hot to walk on?

No! Underfloor Heating systems run at lower temperatures than your radiators (40°C vs 80°C). Radiators are placed on walls and are therefore less effective at circulating heat around a room than underfloor heating which is distributed evenly across the entire surface area of your floor so they do not need to be as warm to achieve the same level of whole room heating. This makes your floor warm and comforting enough for you to comfortably walk barefoot across any flooring type.

How do I choose the Wattage I need for my Underfloor heating?

Wattage or power output determines how quickly the system heats up and can help plug the gaps in a heat-loss room such as a conservatory. 150W is the most common installed wattage but you may need more power depending on the room. If you’re installing electric underfloor heating systems into a new build property, new  building regulations mean that you require less power to effectively heat the room than an older system. 

When do I need to use Insulation with my Underfloor Heating Systems?

Insulated underlay is used under a wide range of Underfloor Heating Systems. The underlay systems help to stop the heating from diffusing downwards, ensuring that all of the heat is generated is forced upwards, into the room. This makes your system more efficient and helps to heat your room more quickly. Insulated underlay is not required for inscreed solutions but is required for Foil & Mat.

What sizes does underfloor heating come in?

Mats & Foil - usually 0.5m in width, are available in 0.5m² which can be purchased in multiples & connected to make the required amount. 

Cable - Cable is available from 0.5m² up to 28m², which again, can be purchased in multiples & connected. 

What is a Cold Tail and why is it important?

“Cold Tail” is the length of unheated cable that connects your underfloor heating cables to the power supply. The Cold Tail can be extended as needed for more irregular installations but is generally sufficient out of the box.

Is Underfloor Heating expensive to run?

By effectively converting your whole floor into a radiator, underfloor heating is much more efficient than an average wall mounted heater. 

Is Underfloor Heating expensive to install?

Electric Underfloor heating systems are far cheaper to install than water based systems, particularly for retrofit. There is obviously some cost involved upfront, but the energy efficiency when compared to more traditional heating options means that it will pay for itself over a number of years.