Andrew Currie of Schlüter-Systems discusses the benefits and installation options for underfloor heating systems, and how to create a cosy and energy-efficient heating solution
What are the key benefits of using underfloor heating systems compared to traditional heating methods?
It all depends on the system. Water-fed (hydronic) systems are designed to operate as a primary heat source, meaning the installation of these systems can directly replace alternative heat sources such as traditional radiators. Electric systems are intended to be used as a secondary heat source, meaning they offer added comfort to floor surfaces like tile by keeping them warm, but they are not designed to heat the air temperature in the room. In this scenario, an electric system would be used alongside another primary heat source such as a radiator system.
Water-fed systems have low supply temperatures of around 30°C to 55°C, whereas a traditional radiator operates on temperatures as high as 60°C or even 70°C. This in turn means lower energy consumption, bringing down the heating costs for the home. The even heat distribution of a water-fed underfloor heating system means the heat is dissipated into the room more evenly while with a traditional radiator, heat is dispersed into the room starting from the closest point to the radiator, leaving cold spots within the air due to movement.
Electric floor heating systems can be configured by different zones, allowing for greater flexibility when it comes to adding comfort to areas within the home that are more frequently used. The low assembly height of electric underfloor heating also makes this type of system suitable for renovation projects or retrofitting.
Underfloor heating also adds comfort to the home, particularly in scenarios where the floor covering is prone to being cold during the winter months, such as tiled floors. With a floor electric heating system underneath warming the tile, it is much more comfortable to step out of the shower on those cold winter mornings!
There are also hygiene benefits to using underfloor heating, particularly in wet areas such as showers which are prone to condensation or a build-up of mould growth. The warmth dries out the area after use, creating a more hygienic and healthier environment.
How do floor heating systems contribute to energy efficiency and reduced utility bills?
Lower supply temperatures than is required from a traditional system like a radiator, means that it is cheaper to run as the water temperature does not need to go up to such a high level.
A low height build-up of some systems reduces the distance between the underfloor heating and the floor covering, making it faster for the heat to reach the surface and reducing heat up and cool down times.
It is also possible to run certain systems using regenerative energy sources, such as heat pumps, which are more energy efficient than alternative heat sources.
How do the different types of systems differ in installation and operation?
Electric underfloor heating systems use wires which are connected to the mains power supply that generates heat to warm the floor covering.
Typically, this type of underfloor heating is available in two different formats – as a loose cable installation or by using mats. Loose cable installations offer more flexibility in the layout of the cable.
Electric systems are controlled by a thermostat and can be adjusted as required to maintain the desired temperature using floor sensors.
Hydronic systems use a network of pipes through which hot water is circulated. These pipes are typically connected to boiler systems, but they can also be connected to other heat sources such as a heat pump. Connecting the pipes to a heat source requires a manifold and mixing valves depending on the heat source.
Are there any considerations to keep in mind when choosing between systems?
There are a few considerations to bear in mind: the type of floor covering, how the underfloor heating will be installed (new build or renovation), the cost of installation, and ongoing cost of running and maintenance. The biggest question to answer is whether you are looking to heat the air space within the room or warm the floor covering.
It’s a common misconception that electric systems can be used as a primary heat source and will heat an entire room and often it will be installed with this intention, only to not perform
as expected. In reality, it’s only intended to keep surfaces warm and add comfort to the floor covering.
While the majority of floor coverings can be used with underfloor heating, it is important to take care with certain coverings. For example, not all carpet is suitable for all underfloor heating, particularly thicker carpets with high tog ratings.
Another key consideration is the type of project where the underfloor heating is required. If a renovation or retrofit project, where height build-up plays an important role in the decision, electric underfloor heating can be more suitable as a secondary heat source. It is additionally more suited where it is only being installed in a few select areas. On the other hand, for new builds or where the entire home is being heated, opt for a hydronic system.
While electric underfloor heating systems are cheaper to install, water-fed systems have lower running costs.
Are there different options based on the type of flooring material used?
Different floor heating systems are suitable for different types of flooring. Electric and hydronic systems work well with a variety of floor finishes such as tile, laminate, hardwood and vinyl. However, some floorings, like carpet and polished concrete, require specific heating systems that are designed to accept those floor coverings.
Can it be retrofitted into existing homes?
Electric underfloor heating systems are ideally suited for renovation or retrofitting into an existing property. Due to the low construction height, there is minimal build up requirements, with many systems being as low as just a few millimetres. These are perfect for scenarios where you may just want to add a bit more comfort to the room by warming the surface of the
floor covering.
What are the maintenance requirements, and are there any potential challenges to be aware of?
Maintenance requirements for floor heating systems may vary depending on the type of system installed. Both electric and hydronic systems generally have lower maintenance needs.
During the installation phase of electric systems, it is important to check the cables are tested before, during and after installation. Afterwards, ensure the thermostat works accurately and that it’s been set up to your requirements.
The main challenge associated with either system is identifying and repairing faults. Since both systems will be installed underneath a floor covering, fault finding should be carried out to identify any fault within the system, with removal of the floor tile being the last resort.
It is recommended to consult with the manufacturer’s guidelines and seek professional advice for ongoing maintenance.
Andrew Currie is training manager at Schlüter-Systems