6 things to consider when using wood flooring for underfloor heating

The weather has certainly taken a turn for the colder, and with it, we have been getting lots of enquiries regarding the compatibility of wood flooring with underfloor heating (UFH). If the flooring is manufactured, installed and maintained correctly, wooden floors are an excellent option for underfloor heating because of their great thermal conductivity and natural warmth.

When installing wood flooring over underfloor heating, most important is to always follow the manufacturer's recommendations for installation and maintenance. 

Ecohardwood has over two decades of experience manufacturing and supplying engineered oak wood flooring to be used with UFH systems. In this article, we share our expertise and advice on what factors to consider when choosing wooden floors for underfloor heating.

1. Wood flooring manufacturing process

Starting from the initial stages, a lot of factors determine whether or not wood is a suitable material for underfloor heating, including how it is dried and manufactured into flooring. At Ecohardwood, precision engineering and excellent craftsmanship are cornerstones of our production process, which begins with the Belgian drying machines. Utilizing state-of-the-art technology, we can incorporate a slow drying process at optimal capacity, ensuring enhanced stability and durability of the product. There is hardly another manufacturer with a drying cycle that lasts an average of 35 days. Oak requires patience, so we go slowly.

Find out more how our double oak flooring is made >>

2. Solid wood flooring or engineered wood flooring

Engineered wood is generally a safer choice than solid wood for UFH systems as it is able to tolerate fluctuations in floor temperature without issues. When selecting wood flooring for underfloor heating, there are two key elements to keep in mind. The first is construction stability which reduces the amount of expansion and contraction as temperatures in the room change. The second factor is thermal conductivity, which refers to how well material is able to transmit heat. The thermal conductivity of wooden flooring varies according to its density, with oak being one of the best in terms of its ability to conduct heat. 

Ecohardwood double oak engineered wood flooring has been a reliable choice for UFH since 1999. Crafted with the most advanced technology, it brings maximum durability, offering optimal thermal conductivity and all-dimensional stability, allowing the heating system to work to its full potential.

Ecohardwood herringbone parquet oak flooring. Colour: Walnut/3481 >> Size: 140mm x 600mm >>. Interior: Katie Malik Studio.

3. Preparing the subfloor for flooring installation

Before receiving your wood flooring, it is important to ensure your underfloor heating has been fully examined and is functioning properly. Preparing the subfloor is one of the most important steps in floor construction, as its quality will determine the performance of the wood flooring.

The ideal subfloor should be sturdy, level, structurally sound and dry. Prior to laying the wood flooring, the humidity of the subfloor must not exceed 1.8% CM. A subfloor's temperature should gradually be reduced to +17°C - +21°C three to four days before installation. During installation, this temperature should be maintained and temperature of the room should be the same. Furthermore, this temperature should be kept constant during the installation, with the temperature of the surrounding room staying the same.

4. Flooring installation

To ensure successful installation always follow the manufacturer's instructions. Some suppliers recommend an acclimatization period for the wood flooring. However, with Ecohardwood's advanced engineering, it is no longer an issue: only unpack the flooring when it's ready to be installed. 

It is important to monitor the temperature and humidity of the room where the flooring is installed, as well as the temperature of the heating system, to ensure that the wood is not exposed to extremes that could cause damage. 

You should choose the glue very carefully when installing wooden floors over underfloor heating. The instructions for adhesives must specify whether they are suitable for heated floors. We recommend using STAUF (Germany) adhesive: SPU-460, PUK-446, MultiLayer.

It is recommended to keep the base temperature at 17°C to 21°C for at least three days after installing the floor. The desired temperature can then be gradually set. 

In situations where the flooring has already been laid, cardboard paper is better suited as a temporary protection sheet than Correx for heated floors, thus safeguarding them from damage.

For a successful combination of underfloor heating and wood flooring, professional help is essential. Homeowners who wish to install heated floors should keep in mind that the process can be quite complex. Find tips on installing wooden floors for underfloor heating here >> or contact Ecohardwood Contractors for professional help and advice: installations@ecohardwood.co.uk, +44 7824 428413.

5. Wood flooring maintenance

When using wooden floors with underfloor heating it is especially important to make gradual changes to your temperature rather than a sudden increase. If you use underfloor heating, do not raise the temperature more than 2-3°C daily and ensure the maximum floor surface temperature does not go above +27°C, with a maximum room temperature of +24°C. To keep heated floors in good condition, relative humidity should stay within the range of 40-60%, and the temperature should stay between 17-21°C. Otherwise, gaps may occur due to the natural qualities of wood.

Using thick rugs and runners with rubber backing on your wood flooring can trap heat and exceed the industry standard of 27°C, resulting in excessive shrinkage of the timber and adhesive issues. If you wish to use rugs, ensure that they are thin enough to let the heat escape easily. To protect your wood flooring, it is important to clean it using the products that are suggested by the manufacturer. Please read wood flooring maintenance guide for more information >>.

6. Impact of wood flooring on UFH

Wood is an effective insulator and has the advantage of keeping the heat in better, leading to greater energy efficiency. With a correctly designed underfloor heating system, its performance won't be compromised by wood flooring's insulating properties. Wood flooring itself doesn't even need heating to be pleasant to walk on barefoot.

Our recommendations are based on years of experience. Please contact us if you are looking for wood flooring in London and the UK and need more specific advice: info@ecohardwood.co.uk, 020 3759 0771.