Cork Underlayment

Cork underlays for underfloor heating require consideration of several important factors. Cork is a natural insulating material, so its use in combination with underfloor heating should be carefully considered.

Is cork suitable for underfloor heating?

Due to their insulating properties, cork underlays are generally not recommended for underfloor heating, especially for water heating. Cork hinders heat conduction, which reduces the efficiency of the heating system.

Exceptions and applications:

Thin cork underlays (e.g., 2 mm) can be used for electric heating, but only if the floor and heating system manufacturer permits this.

There are special technical or mixed cork underlays (e.g., cork + rubber) that are suitable for use with underfloor heating – they have better thermal conductivity than pure cork.

What can you use instead of cork?

The following underlays are most commonly used for underfloor heating:

Polyurethane mineral underlays (PUM) – e.g., cork + rubber. B. Arbiton Secura Thermo.

XPS underlays with low thermal resistance, e.g. Multiprotec 1000.

HDPE underlays (high-density polyethylene) – have good thermal conductivity values.

What should you consider when choosing an underlay?

Thermal transmittance coefficient (R) – the lower the value, the better. For underfloor heating, an R ≤ 0.05 m²K/W is optimal.

Compatibility with underfloor heating – the manufacturer should clearly state this.

Heating type (water or electric).

1. Herstellungsverfahren

Korkunterlage (technisch, Boden):

Hergestellt aus Korkgranulat, das unter hohem Druck und hoher Temperatur gepresst wird.

In der Regel unter Zusatz von synthetischen Klebstoffen oder Polyurethanharzen, was Haltbarkeit, Dichte und Druckfestigkeit erhöht.

Der Produktionsprozess ist optimiert für:

mechanische Festigkeit,

Wärmeleitung,

Schalldämmung,

Druckfestigkeit (wichtig für Böden).

Er hat eine gleichmäßige Struktur und eine hohe Dichte (ca. 200–240 kg/m³).

Rollenkork (z. B. technisch, dekorativ, Modellbau):

In der Regel aus lockerem Granulat hergestellt, das bei geringerem Druck gepresst wird.

Er enthält oft keine oder nur minimale Harzzusätze.

Bei der Herstellung wird Wert auf einfaches Schneiden, Biegen und Montieren gelegt, z. B. an Wänden, Platten und Brettern.

Er hat eine geringere Dichte (ca. 100–160 kg/m³) und eine porösere Struktur. Es kann mehr Luft aufnehmen und dämpft dadurch Geräusche besser, ist aber weniger druckbeständig und leitet Wärme weniger gut.

Is cork substrate suitable for decorative stickers?

YES – provided that the right type of cork is selected:

Type:

A 1–3 mm thick decorative and technical cork roll will work best.

Alternatively, you can use a technical cork substrate, but it must be:

smooth and uniform (without too large pores),

thin (2–3 mm) to adhere well to the wall.

Desirable features for stickers:

Soft and flexible – easy to cut with scissors, a knife or a plotter,

Light – does not fall off the wall,

Thin – does not stick out too much,

Smooth – looks good after sticking and is easy to print / paint.

How to prepare cork for stickers?

1. Choose the right cork roll:

Thickness: 1–2 mm

Density: medium or high (approx. 200 kg/m³) – does not crumble

Structure: fine-grained – provides an aesthetic appearance and easy cutting

2. Cutting:

Precision knife, laser, plotter or manually

You can use templates (e.g. letters, animals, leaves, mandalas)

3. Sticking to the wall:

Stickers can be glued:

double-sided tape (for light shapes),

contact glue (for larger surfaces),

self-adhesive sheet (if the cork is previously covered with glue).

4. Additional finishing (optional):

Painting with acrylic or metallic paints

Varnish for protection

UV printing (if you have access to a printer)