ᐅ Experiences with Cork Flooring and Underfloor Heating?

Hi,

we are currently deciding on the flooring for our new build and have come across cork and its many positive qualities. From what I’ve read, cork tiles are preferable to cork click parquet because of better thermal conductivity.

I’ve also read that the underfloor heating needs to be properly sized for it and that a humidifier is actually necessary to maintain 50-60% humidity. Also, around 20 degrees Celsius (68°F) is important… huh??

Just asking around: who has cork flooring and what are your experiences?

It is illogical to place an insulating material like cork over underfloor heating. Cork does not have "better thermal conductivity" but rather very poor thermal conductivity. That is why it insulates so well and is perceived as warm underfoot. Its thermal conductivity value ranges from 0.035 to 0.046 W/mK. This makes cork a genuine insulating material. Ideal materials for underfloor heating are those with very good thermal conductivity: tiles, polished screed or concrete, natural stone slabs, and metal. Even parquet or wood planks above underfloor heating are borderline.

The suitability of a floor covering for underfloor heating depends on both the thickness of the material and its thermal conductivity. These two factors determine the thermal resistance – the lower it is, the better. The thermal resistance must not exceed 0.15 m²K/W. To calculate this, the entire structure above the underfloor heating must be considered. Any professional flooring or heating/plumbing specialist should be able to perform this calculation.

I have cork flooring on underfloor heating.
It’s great. But it’s glued directly to the screed and only 5mm (0.2 inches) thick. So it’s a thin layer that still feels flexible and works well both in winter and summer.
Whether you choose hardwood, laminate, or cork is almost irrelevant; depending on the construction, they all tend to have lower thermal conductivity than tiles or natural stone.
It mainly depends on the thickness and the installation method.

20 degrees Celsius (68°F) is probably the maximum allowable temperature for the floor with underfloor heating. And yes, humidity is important for a natural product. This also applies to solid wood furniture or partly solid wood pieces. Otherwise, the wood could crack.

wpic schrieb:
Cork does not have a "better thermal conductivity" but rather a very poor one.

What was meant is that in combination with underfloor heating, cork engineered wood flooring should not be used, but instead directly glued cork panels. The installation above the screed will then be approximately 5 mm (0.2 inches) thick (see also #3).

I am familiar with households using cork engineered wood flooring. Even there, temperatures sometimes exceed 20°C (68°F), and no special humidity control measures are taken. Since the surface is sealed, I wouldn’t worry too much about that.

We are currently building with underfloor heating and cork (directly glued). Moving in this summer. So in about 2 years, I’ll be able to share my own experiences. It should work out...