UnderFloor Heating

Floor Heating – Installation and use, a set of rules describing how to heat wood floor with under floor heating.

General Information

The underfloor heating system is a “slow” system. The room slowly reaches the proper temperature but also slowly releases heat. The design of heating system plays significant part, the more balanced and accurate the better. Wood dries out and shrinks under the influence of too much heat. The rapid and large fluctuations in temperature can damage board. Carpets can lead to the accumulation of heat, resulting in shrinkage and cracking of the boards.

The installation method

Floor boards may be glued to the floor directly on cement screed. Ensure whether cement screed is leveled. Cement screed – at least cement D20. The maximum difference in height is 2 mm to 2 meters. It is recommended to use the same brand of barriers vapor proof as adhesives. Boards should be laid down in accordance with guidelines instructions and need to be ensured that the emphasis on the boards for 24 hours after sticking comes to at least 20 kg per m2.

Heating guidance prior installation

The floor cement screed should cure for at least 42 days. The floor should be heated in accordance with set of rules.

Heating the floor lasts 30 days during this process and good ventilation to get rid of moisture is necessary. Once the process comes to an end it requires to verify the moisture of cement screed.

Maximum moisture of cement screed is 1.8% (or 3.0% using barriers vapor proof). Maximum moisture of anhydrite screed is 0.3%.

Heating after installing the floor

During installation wood floor the temperature of cement screed must be from 15 ° C to 18 ° C.

It is important to maintain this temperature at least 5 days after finishing installation.

After a period of five days the temperature may stay slightly increased (by 1 ° C or 2 ° C per day) until the desired maximum temperature is reached.

The maximum temperature of contact cement screed is 28 ° C. The temperature of the contact surface of the cement screed should be measured 3 days after the set temperature.


Heating during the heating season

At the beginning of the heating season the temperature should increase gradually. Maximum by 1 or 2 ° C per day however the maximum temperature measured at the floor surface can not exceed 28 °C. Regardless of the heating system throughout the year, relative humidity of the room must be maintained between 45% – 60%. At the end of the heating season it requires to decrease the temperature gradually. Max by 1 or 2 ° C per day. In order to maintain stable wood floor the temperature should not differ during the day and night.

Technical Values.

  • The value of resistance of heat conduction boards 20mm – 0.118 m2 K / W.
  • The value of resistance of heat conduction boards 15mm – 0.088 m2 K / W.
  • Thermal induction boards 20mm – λ = 0.17 W / mK.
  • Thermal inductions boards 15mm – λ = 0.17 W / mK.
  1. Very good job by writing about underfloor heating.
    I agree in 100% some people do not have any idea how it works and this is the point when professionals have overload incomming jobs to fix problem after cowboy builders.

    Looking foward for more news it will hep many out there to understand some rules.


    • Thanks Mitch this is all about to avoid pushing people to edge of stress.
      CR Team

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