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All about underfloor heating

Underfloor heating


General information


The heated floor in underfloor heating is effectively a large integrated radiator. In designing underfloor heating it is assumed that the surface temperature should be as evenly as possible. Good insulated buildings can be heated entirely by underfloor heating, so no extra radiators are needed. With less insulated buildings additional heating will be required.


To prevent damage to the floor, the water running through the pipes in the floor may not be hotter than 60 degrees. The temperature in the underfloor heating system is usually set to a maximum temperature of 55 degrees. Usually this setting is additionally protected by a thermostat, which will turn off the pump of the system when the temperature is too high. The working temperature of the floor will vary between 22 and 34 degrees, depending on the water temperature control, the mixing system and the distance between the pipes in the floor.


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Types of underfloor heating systems


Underfloor heating can be divided into 2 groups, namely:


– main heating and – auxiliary heating


Main heating


The room temperature is regulated by the heat output of the floor. According to the current insulation standards, undefloor heating can be applied as mains heating perfectly, so without radiators. In older homes, with poor insulation, it may be possible that the heat output of the underfloor heating is not sufficient. It is possible to place a small ornate radiator, which on a chilly evening can heat up quickly when the underfloor heating system is heating up. Also when according to the calculation, additional heating is required, the underfloor heating can be used as the main heat source. The heat emission is usually approx. 100 watt/m².


With current insulation standards, in principle a pipe distance of more than 15 cm may be applied. In general a good result for main heating will be achieved with a pipe distance of 10 cm. The installers of underfloor heating Stirling for instance can advise you on the design and specification in Scotland.


By reducing the pipe distance, the warming up process and the required water temperature is lower and the average temperature of the floor is lower as well. As a result, the heat content of the cement mass is reduced, making the room temperature more comfortable. A fast heat-up with lots of comfortable living pleasure arises when using a mutual tube distance of 10 cm. This distance is therefore highly recommended for the living room, study and the bathroom.


Auxiliary heater


Heating the floor as nauxiliary heat is primarily done for the comfort and fighting of a cold floor. To install underfloor heating as main heating is excellent, but to use as auxiliary heating, simply lower the water temperature. The advantage is a faster warm-up and a much more even temperature of the floor. The heat emission is usually 40-50 watt/m². With the current insulation standards, in principle a pipe distance of 25 cm may be applied. A good result is achieved with a pipe distance of ca. 20 cm.


Underfloor heating comfort


Compared with ordinary hot water water central heating systems, underfloor heating gives an even, comfortable heat over the entire floor area. A larger and more widespread warming surface at a lower heat output creates a pleasant feeling. The room temperature will therefore be experienced as higher than it actually is.  The heat fro, underfloor heating is for ca. 60% radiant heat. The share of radiant heat that panel radiators emit is approximately 40%, the remaining heat is rising warm air or convection-heat. Underfloor heating gives you a continuous uniformly distributed comfortable feeling.


Underfloor heating & temperature


The temperature difference between the floor and the ceiling, measured at about 20 cm above the floor and about 20 cm below the ceiling is only 1 to 2° c, with underfloor heating. With heating by means of radiators and convectors, differences of up to 4 to 7 °c are possible. The temperature distribution in a room with underfloor heating approaches the ideal temperature distribution very strongly. This in contrary to the temperature distribution with a conventional hot water heating system.


Extra power


Additional heating power can be realized by fitting so-called ‘edge zones ‘ in the floor or the placement of one or more additional radiators/heaters. In an edge zone is in the floor the surface temperature has a higher value. This value must not exceed 35 ° c. The width of an edge zone should never exceed 1 meter. You can also add additional power through wall heating.


Underfloor heating thermostat


With conventional heating by means of radiators, you need a lot of heat to bring a room up to temperature. An underfloor heating thermostat regulates the temperature and heats the room continuously. This allows you to turn down the thermostat more than with conventional radiator heating.


Advantages of floor heating thermostat


Thermostad controled underfloor heating has various advantages. So it distributes the heat evenly throughou the entire floor whereas with central heating a lot of heat is lost by air circulation. Other benefits of underfloor heating thermostat are:

    • The control of the temperature of the floor heating in every room.


    • A free choice of floordesign in your room. Radiators are often in the wrong place. A lot of furniture can not be placed in the vicinity of a heat source. With underfloor heating you don’t have that problem.


    • You save the environment and money at the same time because the thermostat of your underfloor heating can be set 1-2 ° c lower than conventional radiators.


    • Underfloor heating contributes to better health and hygiéne by lower air humidity.

Wooden floors & underfloor heating


Parquet, other wooden floors and laminate can be combined easily with underfloor heating and makes your floor pleasant to touch. In addition to that, laminate and parquet add a lot to the atmosphere. Contact the manufacturer of your laminate to ask if it is suitable for underfloor heating. Preferably underfloor heating should only be used under solid, dry and hard woods. These include wooden floors of oak, teak or merbau. 


Carpeted floors


Underfloor heating can be applied virtually anywhere. The operation of floor heating is based on heat radiation and heat transfer on the surface of the floor. If the surface is covered with a floor covering that lets the heat through slowly, then the heat output will be reduced. This can partly be compensated by increasing the water temperature in the underfloor heating, but this will also increase the heat loss to the Foundation. It is therefore better to increase the pip density. Each carpeted floor has a different heat conductivity and heat transfers. The manufacturer can provide the necessary information and if it is suitable for underfloor heating.


Natural stone or tiles


With these floors, the best heat transfer results can be achieved. As a result, these floor finishes are also excellent when the underfloor heating system is the main heating.


Linoleum & Marmoleum


After natural stone and flags this is a floor covering that is ideal. Heat transfer of this is almost equal to the heat transfer from glued flagstones. If it is glued on the entire floor than this also the case as main heating.




This is only possible if it is glued over the entire bottom and if the back is suitable for underfloor heating. If glued thin carpet can also be applied as a main heating. Flooring with a foam backing to the back is restricted or not suitable at all.



Frequently asked questions


Question: how long should I wait with laying the tiles after the underfloor heating is installed and the screed has hardened and when can it be switched on? The heated floor in underfloor heating Edinburgh is a large integrated radiator. In the design of underfloor heating it is assumed that the surface temperature is as evenly as possible. Well insulated buildings can be heated entirely by underfloor heating. At less well insulated buildings there is additional heating required. Question: which floor height do mI need at least need when I want underfloor heating? You should take into account the fact that the best heat dissipation occurs when there is 5 cm screed on top of the pipe.  Question: should my current radiators linger? When you choose for extra heating then there will always be another heat source needed. With mains heating it is also advisable as an external heat source. This allows the space to be warmed up more quickly and than by thermostatic control the underfloor heating will take over.


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