Cork backing. Methods for laying cork underlay Rubberized underlay

Everyone knows that such types flooring, like parquet and parquet boards, laminate or carpet, are laid on a special substrate. Why is it needed? Firstly, to insulate the coating from moisture, and also as sound and heat insulation. Today in construction stores you can buy such insulating materials: IZOflex (foamed polyethylene), Izopor, Tuplex, cork backing, Icopal Parkolag. As you can see, there is a choice, but it’s up to you to decide what is best to use as a bedding under the floor. Some focus on more affordable material, while others prefer high-quality and durable material made from natural cork.

To make cork backing, crushed cork oak bark is used. Available in the form of canvas with a thickness of 2 to 4 mm. Technical cork in rolls is durable material, which is not afraid of moisture, is resistant to fungi and mold, has excellent heat and soundproofing properties, simple and easy to install, easy to cut.

Specifications:

Thermal conductivity – 0.042 kcal. mm. S.ch.
Tensile strength – close to 2 kg/cm2
Density – 200-220 kg/m
Fire resistance – MH, does not support combustion, does not emit toxic gases (ASTM-C-209)
Sound absorption – when laid on concrete base 100mm, the noise level is reduced by 50 dB at a frequency of 1600-4000Hz.
Ability to compress and recover – at a load of 7 kg/cm2: initially – 10%, residual (after an hour) – 1.3%.
Possible deviation from dimensions – width and length +/- 0.5 mm, thickness +/- 0.2 mm.

Laying

Under the cork backing you must first put plastic film for protection against moisture. The hydraulic barrier is laid so that it extends 5 cm onto the wall. The film strips are laid overlapping (10cm) and secured with a special adhesive tape. Do not use nails, staples or screws to secure the film, as this will weaken the moisture-proofing effect.

Before installation, rolls of cork backing must be unpacked and left in the room for a day. Cut the strips required length according to the size of the room with a margin so that when laying the material it extends 5cm onto the walls and completely covers the film. Lay the material so that there are no gaps between the strips. Glue the parts of the backing together with adhesive tape so that it does not move apart. Do not secure the plug to the floor using mechanical fasteners.

Application of roll substrate AcoustiCORK C11 and Cork 4U

Today, agglomerated cork substrate AcoustiCORK C11 and Cork 4U, which is produced in rolls and sheets, is very popular and is widely used as thermal and sound insulation of floors. It can be used under parquet boards, floating floors, panel parquet, ceramic tiles, carpet, linoleum. It perfectly reduces noise inside building structure, reduces heat loss, increases walking comfort, levels the surface, increases the service life of the coating, ideally reduces impact noise and the sound of footsteps on laminated floors.

It should be taken into account that for each type of coating a substrate of a certain type and thickness is used. For example, type T11, 3mm thick, is used for parquet and solid boards, for carpets C61 (5mm), for floating floors (parquet boards, laminated parquet and other types castle covering) – C31 (2.5mm), for ceramic tiles- T61 (5mm) and T71 (2mm). It should be noted that the thicker the material, the better its sound-proofing and heat-insulating properties.

Price of roll substrate (Portugal)

The cost of the material depends on its thickness. For example, a roll 1m wide and 10m long, with a thickness of 2mm, costs 750 rubles (75 rubles per m2). A thicker cork substrate is produced in sheets measuring 915x610x4 mm, sheet area 0.56 m2, the price of a sheet with a thickness of 4 mm is 100 rubles (179 rubles m2), a thickness of 6 mm is 150 rubles (269 rubles m2). Sheet technical cork can be used not only for floor coverings, but also for insulating walls, roofs, ceilings, as well as in a floor heating system.

Any floor covering: be it laminate, linoleum, parquet or solid boards, require the use special substrates designed to extend the service life of the selected material. The characteristics of the cork substrate, like the cork itself, are unique in their own way . This is one of the most popular and environmentally friendly materials, rightfully recognized as ideal, because along with hypoallergenicity, the lining boasts many advantages.

Properties and characteristics of cork substrate

Classic cork flooring, also called technical, is made from finely ground cork oak bark. When pressed, the bark begins to release a natural substance called suberin.

Its main purpose is to glue the bark granules together and make the material waterproof. Laying cork backing is appropriate in rooms with high level load permeability on the floor covering.

A prerequisite for using cork is a stable level of humidity.

Functions of a technical plug

Eliminating deformation of the floor covering by leveling differences (no more than 2 mm in size) and smoothing the surface.
Minimizing the accumulation of condensate vapors.
Increasing sound and heat insulation parameters.
Uniform distribution of load on the coating, which is especially important for laminate and parquet floors.

Cork backing, the price of which varies significantly depending on the thickness of the material, is divided into two groups according to the form of release:

Sheet cork, the thickness of which ranges from 4 to 10 mm. Standard sheet parameters are 915×610 mm.
Cork substrate in a roll with a thickness varying from 2 to 4 mm, length - 10 and 25 m, width - 1 m.

Technical characteristics of cork substrate

density – 200-250 kg/cm2;
initial compression when exposed to a square centimeter of 7 kg - 10%;
residual compression after an hour’s exposure – 0.7%;
tensile strength – 2 kg/cm2;
humidity of cork composite ≤ 7%;
thermal conductivity – at the level of 0.042 W/(m∙K);
noise absorption – 16 dB;
fire resistance – high.

Types of cork backing

Considering different types condition of the subfloor, manufacturers have invented two improved types of cork underlayment:

It is characterized by excellent moisture resistance, which makes it possible to use it as a lining material in rooms with unstable humidity levels. The base is kraft paper. Bitumen is applied to it, sprinkled with cork granules, the size of which does not exceed 3 mm.

The bitumen layer is a good waterproofing agent, and the rough bark coating provides proper ventilation, helping to eliminate excess moisture between the base of the floor and the lining.

Its peculiarity lies in the installation method, which involves laying the cork layer down. The strong and durable bitumen-cork substrate has one significant drawback, especially relevant for household use.

Bitumen cannot be classified as environmentally friendly pure materials, since it is fire hazardous and toxic, so it is better not to use such a lining in residential areas.

Known for its superelasticity due to the addition of synthetic rubber to oak bark. Bonding of cork chips and synthetic rubber is carried out using polyurethane binding agents. Such a substrate - perfect option for the “warm floor” system, since it is endowed with impeccable thermal conductivity.

Due to the presence of rubber in the composition, the material is moisture resistant and has increased shock-absorbing properties. It is the rubberized samples that are famous for the lowest percentage of changes in performance over time.

The rubber-cork substrate has another advantage, which is its excellent ability to “dampen” vibrations emitted by electrical appliances.

The most significant advantage is durability. The service life of the lining is measured not in decades, but in centuries, and can reach 200 years.

Wear resistance. Not only the thicker sheet cork, but also the cork backing in a roll boasts excellent mechanical stability. The material is very elastic and moderately porous, which indicates its impeccable resistance to various influences.

Flooring wears out much faster than cork underlayment. A common misconception is that it should last longer than the selected type of coating. However, it is the substrate that bears the main load impacts.

Sufficient thickness of the cork backing, correctly selected depending on the condition of the base and the type of flooring material, will allow it to serve faithfully even after replacing the worn out decorative covering.

Despite the fact that cork flooring is a wood product, it is practically not susceptible to damage from wood pests or rodents. This advantage is due to the special sanitary treatment carried out at the production stage.

Versatility is another undeniable advantage. Laying cork backing is possible on any surface. Moreover, it can be used as a decorative wall material or for any other purpose.

Thanks to its elasticity, the lining is very easy to work with, given that it is unpretentious to the condition of the base.

Among the disadvantages, it can be noted that with prolonged contact with heavy objects, the material tends to deform (press through).

The cork backing, the price of which is quite high compared to cheaper polypropylene options, may seem unaffordable to many, which is considered the second disadvantage.

The cork substrate must meet the requirements of the installation location. For example, for residential excessively humid or rooms with variable humidity, it is better to give preference to rubber-cork ones, since they are distinguished by excellent moisture resistance due to the presence of rubber, and the necessary environmental friendliness.

For storage facilities with an unstable humidity background, you can choose the bitumen-cork variety. If we are talking about relatively dry rooms, then you can use a classic technical stopper.

However, the classic type, unlike the rubber and bitumen subtypes, is not recommended for use with water-heated floors, since the material cannot boast of high thermal conductivity.

To get out of this situation, you should look for a specialized cork substrate with a foil coating that will not allow heat to dissipate.

The thickness of the cork substrate is the next criterion for selection. So, under the laminate, 2 or 4 mm of lining is enough. It guarantees and good protection boards, and proper shock absorption, and, most importantly, a reliable connection of the locking elements.

In addition, the coating will provide pleasant cushioning underfoot. A large thickness will lead to excessive springiness of the laminate floor, and as a result, to loosening and rapid wear of the locks.

Regarding parquet and solid board A similar thickness is appropriate; for linoleum and tiles, the millimeter is not critical.

It is quite difficult to stick a linoleum sheet onto a classic cork, so it is better to prefer a floating flooring.

The unique characteristics of cork backing consistently attract buyers. This is perhaps the most environmentally friendly and practical material used as a lining.

It is endowed with all the qualities necessary for use both in residential (if it is a classic or rubber-cork substrate) and in industrial (bitumen-cork substrate) premises, which explains its popularity, despite its high cost.

Characteristics of cork substrate, video

Undoubtedly, one of the most practical, affordable and popular types of flooring is laminate, since this material has excellent quality and aesthetic characteristics, has a long service life and is very easy to install.

But, in order to extend the service life of this flooring as long as possible, and also reduce the load on locking connections, it is imperative to provide it with a reliable and high-quality foundation, namely a substrate.

Important! In addition to protecting the material, the substrate is additionally a sound and heat insulator.

An ideal, reliable and high-quality type of substrate for laminate flooring is a cork substrate (cork substrate), which is an environmentally friendly and natural material.

Why is it necessary to use a laminate underlay?

The laminate underlay performs many additional functions. Since laminate is a fairly rigid coating that is laid in a floating pattern, in which the coating does not have to be fixed to either the base or the walls, the underlay, together with the expansion pattern, performs the function of cutting off and provides insulation.

Helpful information! One of the functions that the lining layer performs is shock absorption. As already noted, laminated coating laid without fixing to the surface or walls, and if the surface is uneven, gaps may form between the floor and the laminate over time.

When exposed to constant loads, cracks may appear during operation, which leads to a decrease in the service life of the floor covering used. the underlay evenly distributes the load over the entire surface of the laminate floor.

In addition, if on some area of the floor under the laminate, when moving in this area, loud noise and a characteristic knock. The underlay also provides additional sound and heat insulation.

What types of substrate are there?

There are several types of laminate substrates on the market for construction and finishing materials, and when choosing one or another option, it is necessary to take into account the technical specifications. Qualitative parameters, economic aspect and type of laminated coating.

Polyethylene foam backing

This type of lining base, due to its low cost, can be classified as the most common and popular option.

The material is moisture resistant, prevents the proliferation of microorganisms and insects and has good sound insulation and thermal insulation characteristics. The material is easy to install and can be easily cut into strips of required size.

The only disadvantage of polyethylene foam substrate is that over time the material can sag, which leads to a decrease in the service life of the laminated coating.

Foil backing

This type of substrate is represented by a foamed polymer on one side of which a layer is applied aluminum foil. This type of underlay is advisable to use if it is necessary to enhance the thermal insulation of the floor, so the foil underlay is the most the best option for heated floors under laminate.

Should be considered what this material has high cost, therefore it is uneconomical to use it as a base for laminate floors without heating.

This type of lining material has quite original design, consisting of two layers polymer film, between which polystyrene granules are placed.

This base for laminate has excellent vapor barrier properties, so it is recommended to install it in rooms with increased level humidity.

Cork backing

This version of the base for laminate is environmentally friendly and natural materials, which does not contain any harmful chemical impurities and has high quality parameters.

It is made by crushing and pressing under pressure from the bark of the cork tree. Available in the form of rolls or slabs. The gluing of particles occurs thanks to a special adhesive substance, suberin, which is contained in the bark of the tree, so the material does not release toxic particles into the air that are harmful to human health. because this type The material has a high cost, it is not practical and impractical to use for economy class laminate.

Combined substrates

The bitumen-cork substrate is made on durable cardboard or paper, one side of which is impregnated with bitumen, and a layer of pressed cork is applied to the other surface. This design allows it to absorb excess moisture, so there is no need to lay an additional layer of waterproofing. Always lay the substrate with the cork side down.

Rubber-cork backing

The rubber-cork backing is made from a mixture of finely ground cork and rubber; it provides the best sound insulation and is not susceptible to moisture. The disadvantage of the material is its high cost.

How to determine the thickness of the underlayment?

Many novice craftsmen mistakenly believe that using thicker underlays can eliminate floor unevenness, but this is not always the case. If the floor surface has a strong curvature, the situation can only be corrected by replacing the screed or self-leveling floor.

Increasing the thickness of the lining material under the laminate can lead to deformation loads inside the material, so it is very important to correctly determine the thickness of the lining layer, since otherwise the load on the interlocking joints of the floor covering increases and, over time, dents and cracks may appear.

Advice! Laminate floors should not be laid on a substrate whose thickness exceeds 3 mm, while if the floor surface is perfectly flat, the thickness of the lining layer can be 2 mm.

Detailed description and characteristics of the cork substrate

Cork backing has excellent quality parameters and is considered the most popular type of lining material for laminate flooring.
This type of material is not subject to deformation, is environmentally friendly, has high noise insulation, water absorption, and heat insulation parameters, is not susceptible to rotting and mold, and is hypoallergenic. But, cork backing has a fairly high cost.
It is advisable to install a cork underlay if the most durable laminate is used and there are no plans to replace the floor covering in the next few years.

Technology of laying the substrate under the laminate

Before carrying out work, the substrate is unpacked and left for a day in the room in which the work will be carried out. The material must “get used to” and adapt to the microclimate conditions in the room.

Important! The material should only be laid perpendicular to the laminate panels. This installation method will prevent the floor covering from moving during operation, so it is very important to think in advance about the direction of laying the laminate.

Before laying the underlayment, it is necessary to prepare the floor surface. The floor must be smooth, without any defects and absolutely dry. The base is thoroughly cleaned of dust, all cracks are puttied. To prevent mold growth, concrete surface treated with an antifungal primer.

At the next stage, a layer of vapor barrier (waterproofing) is laid, using for this purpose a construction polyethylene film, the edges of which should protrude by 15-20 cm, while at the junction of the seams the overlap should be at least 10 cm.

All connections are fixed using construction tape.

Important! You should not use a stapler or nails to fix the waterproofing layer, as in this case the vapor barrier will be damaged.

Cork backing is cut into strips required size, placing them close to each other, avoiding the formation of overlaps or gaps between them. Using tape, adjacent sheets are connected to each other.

Important! When laying the substrate, you need to leave an expansion gap of at least 1 cm around the entire perimeter of the room, since thermal expansion of the substrate is possible.

Treat the substrate with water-repellent agents and begin laying the laminate.

Important! The cork substrate should not be laid in more than one layer. otherwise damage to the floor covering may occur.

Conclusion

Before laying a laminate flooring, in order to increase its service life, it is imperative to lay the underlay.

The lining layer, in addition to its main purpose, performs many other functions and plays an important role in the formation of the floor. Photos and educational video materials. which are presented on our website will help you correctly lay the underlay, laminate and make your home cozy and comfortable to live in!

Laminate is an excellent substitute for natural parquet, but its price is several times lower. Only a true parquet connoisseur can distinguish parquet from laminate. However, if external differences there is practically no difference between materials, then they exist between performance characteristics. And the main one is wear resistance. For laminate it is much lower, since it is made by dry pressing of wood dust formed during furniture production, then the thickness of the panel is significantly less than that of parquet boards. If the laminate is laid on bare concrete, then you will have to face problems such as a cold floor and its “musicality”. Every step will ring loudly in the apartment.

To eliminate all these imperfections of the laminate, the underlay is laid.

Types of substrates

The traffic jam is not the only one natural material for the substrate. Substrates come from:

Artificial material (“Izoshum”, “Tuplex”, “Izolon”).
Cork oak bark (natural pressed material).
Cork oak bark with technical rubber crumbs.
Kraft paper impregnated with bitumen and sprinkled with cork chips.

The most preferred option for a laminate substrate is a cork substrate. The reason is simple - the proximity of the origin of the materials (coating and substrate), environmental friendliness (very good for housing).

But the traffic jam has its own characteristics. Like any wood fiber, it can swell under the influence of moisture. Therefore, if the cork is placed in the kitchen or bathroom (where the humidity is high), then it should first be treated with a water-repellent agent (Aquastop, for example).

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"Golden mean" between thin and thick substrate

If you lay the laminate on a thicker cork base, you can get a “floating” type floor that will not be able to withstand heavy loads. 4 millimeters is a critical value for the thickness of the substrate. However, 2 millimeters will be enough to protect the laminate.

In what form is cork backing available?

Roll materials.
Plates or sheets 915x610 millimeters.

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How to prepare the base?

It is easy to install cork as a backing under the laminate. You don’t need any particularly complex tools, or any construction tricks.

Need to make sure it's reliable wooden base, if there is one on the concrete floor. If it is strong enough, then the cork backing and laminate are laid directly on it. You should not lay a waterproofing layer on wood, since it itself is a “breathable” material. But the presence of waterproofing under the tree will remain unclear.

If we talk about the waterproofing layer, which is recommended by manufacturers of the same laminate, then it makes sense to lay it if the apartment is on the ground floor, and there is an unheated underfloor basement. To prevent the formation of condensation on the floor side of the apartment, waterproofing can be installed. In other cases, this work will be an unreasonable waste of time and money.

For some time, a layer of waterproofing can protect lower neighbors in an emergency flood situation. But laminate flooring definitely won’t survive in an apartment. If you want to arrange everything correctly, then use modern membrane materials, allowing excess moisture to pass through the space only in one direction. For a laminate flooring and its substrate, the end point of this direction will be the floor located underneath them. Regular polyethylene will contribute to the accumulation of moisture under the substrate. And without such waterproofing, moisture can evaporate through all sorts of cracks located around the perimeter of the coating. When using vapor-permeable membranes, you need to think about how excess moisture will be removed from under the “layer cake”.

If all floor coverings have been removed up to concrete base, then it is important to make sure that there are no large fluctuations in heights and potholes in case the construction was carried out carelessly and unprofessionally. If any are found, efforts must be made to eliminate them. There are many ways to get rid of it. The worst of them is the installation of a cement-concrete screed. It is difficult to do it yourself without violating the solution preparation technology. The main mistakes are making a thicker screed or trying to speed up the hardening of concrete, which is also unacceptable in the work. The hardened screed cracks, becomes dusty, and is subject to destruction. If you really want to, it is better to use ready-made mixtures containing synthetic microfiber fibers. Such mixtures are not uncommon at the moment in construction stores. The hardening process takes much less time and the base is much smoother.

The most acceptable way for a homeowner to install a subfloor is to lay the floor on wooden joists. This method is not without its drawback: lowering the ceiling in the room.