Insulation materials

Technical plug. Material features, characteristics and application

When it comes to natural, environmentally friendly building materials, one of the first materials to remember is cork. Today it is used in different fields and for different purposes. Technical cork is used for heat and sound insulation of premises, as well as a substrate for many floor coverings, for example, laminate. What are the features of this material, why it is so popular – we will tell you in this article, and also dwell on the technical characteristics and methods of using a technical plug.

Features of cork materials and their advantages

Why are cork materials considered sustainable? The fact is that the raw material for their production is the bark of a tree – cork oak. And in the production of final materials, no synthetic substances are used, the material is obtained exclusively natural.

Cork oaks are native to the Mediterranean countries, of which Portugal is considered the largest supplier of cork materials. When the cork oak is 25 years old, the bark is removed for the first time. Thanks to natural intensive regeneration, the bark grows again, and the tree does not die. After 9 years, you can remove the bark from the tree again, and with each removal the quality of the bark gets better and better..

Technical plug preparation

After stripping, the bark is dried in natural conditions, and then sent to the plant, where various products are produced. For the production of technical cork, the bark is crushed, and then the granules of the crushed bark are pressed under pressure and treated with steam. At the same time, additional binders are not used, as is the case with artificial polymers, since the cork itself contains suberin – a natural glue, which is more than 45% in the material. The technology for the production of cork materials is called agglomeration, which is why the positions of technical cork are called black cork agglomerate and white cork agglomerate. They differ from each other only in that the bark of tree branches is used for the white agglomerate, and the bark of the trunk is used for the black one..

The unique feature of the cork is its honeycomb structure. For every 1 cm3 of plug, there are up to 40 million cell cells. Each cell has the shape of a polyhedron with 14 faces, the inner space of the polyhedron is filled with a gaseous mixture. It is thanks to this peculiar structure that cork materials have excellent thermal insulation properties, and also do not allow water and gaseous substances to pass through. The cells are separated by intercellular septa.

Cork materials have both purely technical advantages over others, and have other advantages that can play a decisive role in the selection of an insulating material..

Advantages of technical plug:

  • Complete environmental friendliness and hypoallergenicity. No harmful substances are released from cork materials, neither at rest, nor during heating or burning.
  • The cork easily regains its shape after compression or twisting, bending. The material is extremely resilient. Even after years of use, it does not crumple or trample, but continues to spring pleasantly underfoot..
  • Cork is a natural antiseptic, so building materials from it are not subject to rotting and the appearance of mold..
  • Cork is not eaten by rodents and insects.
  • Cork materials are not afraid of ultraviolet radiation and do not transmit it.
  • Do not electrify, do not accumulate static electricity.
  • Cork materials do not emit phenols, chlorine and cyanides or other hazardous substances during combustion. To prevent the cork from burning, it is treated with a special substance, after which it can be classified as class G1 (non-combustible substances).
  • Due to its natural unique structure, the cork has a low thermal conductivity, which makes it possible to use it for heat insulation or thermal insulation of buildings..
  • Also, the cork has excellent sound insulation properties, reducing noise coming from the street..
  • The material is convenient to use, durable and versatile.
  • Safe for the environment as it is recycled naturally.
  • Technical cork retains all its properties at low temperatures, therefore it is used in the production of refrigerating chambers.
  • Water-resistant cork allows you not to worry about the material even in case of flooding at home.
  • The following can be distinguished as exceptional features: the plug reduces the level of radioactive radiation, and also isolates from the harmful effects of technopathogenic zones.

Also, cork materials are not afraid of alkalis and other substances..

Depending on the purpose for which it will be used, you can buy technical cork in two forms: in rolls or in sheets. They differ not only in the form of release, but also in the thickness of the material. Let’s consider in more detail the characteristics and features of the use of rolled and sheet technical cork.

Technical cork in rolls

Technical cork in rolls

Technical roll cork is also called cork backing. It is usually produced in rolls with a width of 1000 and 1400 mm, but the thickness of the material is more important. The thickness of the cork in rolls can be 2 mm, 2.5 mm, 3 mm, 4 mm, 8 mm, 10 mm.

Cork specifications

Cork specifications

From the table above, you can get information about the technical characteristics of roll and sheet positions of technical plug.

To the above, we can add that the service life of the roll substrate is equal to the service life of the building, it is one of the most durable natural materials.

The moisture content of the material is maximum 7%, which is extremely important during installation and further operation.

Permanent deformation 0.2%. Thanks to such low performance, the cork material does not wrinkle and returns to its previous shape after prolonged stress. For example, already 1.5 minutes after the cessation of exposure, the residual deformation is only 0.35%, after 15 minutes – already 0.25%, and after 150 minutes – only 0.17%.

Roll cork is inert to various chemicals.

Pay attention to the sound insulation factor. With a plug thickness of 2 mm, it is 16 dB, and with a larger thickness (4 – 10 mm), the sound absorption coefficient can increase to 22 dB or more..

Also important is the sound shock resistance – 12 dB.

The deformation modulus of elasticity is 2000 – 2500 kgf / cm2. This suggests that the material is able to withstand colossal loads without significant deformation and does not undergo destruction. Thanks to these properties, it can be used on many construction sites where the pressure of heavy equipment, for example, is very high..

Application of technical cork in rolls

Application of technical cork in rolls

Rolled technical cork is used as a heat-insulating and sound-insulating material. It is laid under laminate, linoleum, parquet board and panel parquet, performing the function of a substrate that reduces the transmission of clapping sounds from movement on a wooden floor. Also, the underlay serves as insulation between the base under the flooring and the flooring itself..

When installing underfloor heating, roll cork is also used and performs all the same functions..

An important advantage of using roll cork when arranging floors is that the material allows you to level small irregularities in the base, and also has excellent shock-absorbing properties..

Also, roll cork can be used for insulation and sound insulation of walls and ceilings, but this is less convenient than using sheet technical cork. The fact is that the roll cork must be straightened to fix it on the surface, and the sheets are already even. As an underlay on the floor, roll cork is ideal as it is pressed down by the floor covering. When insulating walls and ceilings, this is inconvenient..

Application of technical cork in rolls 1

When laying a rolled technical cork on the floor, the temperature in the room should not be lower than +10 ° С, the humidity should not be higher than 75%. Laying can be started one day after the roll is unpacked and the material is straightened. The floor screed must be even, clean and dry, the residual moisture must not exceed 2.5%. During installation, the roll is cut into the required lengths, which are laid on the floor surface without gaps. The joints are carefully glued. By the way, you cannot fix the roll substrate to the floor mechanically, only glue it.

Technical sheet cork

Technical sheet cork

Technical cork in the form of sheets differs from rolled cork only in material strength and dimensions. Usually it is a 940×640 mm plate with a thickness of 2 to 10 mm. The most common positions are cork sheets with a thickness of 4, 6 and 10 mm. For sheet technical cork, the price depends on the thickness of the material, because it also affects the technical properties..

Sheet cork specifications

Sheet cork specifications

In the table of characteristics of sheet cork, it is clearly seen that the so-called white agglomerate has high sound absorption, which means that it is more suitable for soundproofing rooms..

In addition, I would like to note that the material easily recovers after applying pressure. For example, when a load of 7 kg / cm2 is applied, the compression is 10%, and after an hour it is already 0.7%.

The sound absorption coefficient of the cork sheet measured at 2.1 kHz is 0.85. This can significantly reduce noise as well as completely eliminate reverberation. This is especially important when soundproofing recording studios and cinemas. After all, reverberation is the propagation of the sound of a reflected sound – an echo.

Application of technical sheet cork

Application of sheet cork

Technical sheet cork is used for thermal insulation and soundproofing of premises. She insulates the floor, walls, ceilings, ceiling. In the room, which is isolated by a technical plug, there is absolutely no echo and minimal noise from the street.

Technical cork can be found in any environment, so it can be used both for finishing the external facade and for interior decoration of the room, and as a substrate for flooring and underfloor heating systems, as well as roll cork. As a heater, technical cork can be used in ceilings, on the floor, and on the walls, and on the roof, and on external walls..

Important! The only limitation on the use of technical plugs is the production facilities where metal processing is carried out. The fact is that metal shavings quickly clog the pores of the plug, and it ceases to perform its functions..

In combination with other materials, technical cork significantly reduces noise and reverberation. Also, the plug is used to reduce vibrations coming from machine tools and other mechanisms, regardless of what load they put on the plug..

Insulation of a building with a technical plug

The plug provides the best sound absorption in the high frequency range above 1.5 kHz. This makes it possible to completely isolate the room from harsh loud sounds coming from the street, such as barking dogs or screaming. Also, when soundproofing partitions between rooms, you can isolate the room so that you cannot hear a stereo system or TV..

Soundproofing cork

But the cork is not capable of reducing the vibration noise that is transmitted over the floors, or the vibration of mechanisms. Actually, like any sound insulation.

Insulating walls and ceilings with cork

For the best sound insulation, the room is finished with a cork in a complex: ceiling + walls + floor. To improve the acoustic properties of the cork, it is advisable not to cover it with another finishing material. You can, for example, use decorative cork panels in addition to technical cork..

The technology for installing sheet technical plugs practically does not differ from the installation of a roll substrate. The only difference is that the sheet material can be laid immediately, since it is already even. The sheets are glued to the surface with special glue, always end-to-end. Sometimes sheets are fixed mechanically, but much less often.

And finally, the advantages of sheet cork over rolled cork, which were noticed by professional installers:

  • The leaf cork is denser.
  • It is easier to install, since one person can handle it, as opposed to a roll one, where an assistant is definitely needed.
  • The sheet plug does not need to be leveled.
  • It is more convenient to cut to the required size.
  • The sheet cork does not break or crack, as it is not rolled up.

Technical plug is a versatile material that is used in almost all places where insulation is needed: both indoors and outdoors. The indisputable advantage is water resistance and non-susceptibility to the influence of mold, rodents, insects. The only drawback of technical cork is its high price compared to synthetic insulating materials of the same class..