EP3559371A1

EP3559371A1 - Spoolable soundproofing system to be placed under floor tiles

Info

Publication number: EP3559371A1
Application number: EP17832283.0A
Authority: EP
Inventors: Karine WIETZERBIN; Daniel Comoy
Original assignee: Saint Gobain Weber SA
Current assignee: Saint Gobain Weber SA
Priority date: 2016-12-22
Filing date: 2017-12-21
Publication date: 2019-10-30
Anticipated expiration: 2037-12-21
Also published as: FR3061223A1; FR3061222B1; FR3061222A1; WO2018115780A1; EP3559371B1; FR3061223B1

Abstract

The present invention relates to a method for manufacturing a tiled floor on a substrate to be covered (5) using a soundproofing system in the form of rolls intended for being positioned on a substrate and directly under floor tiles, which is made up of an insulating portion comprising at least one flexible sublayer (2a) providing the soundproofing and at least one other sublayer providing the mechanical strength (2b-l) positioned opposite the floor tiles (4), the two sublayers being rigidly connected to one another.

Description

ROLL-IN ACOUSTIC INSULATION SYSTEM WITH TILES

The present invention relates to a sound insulation system in the form of a roll intended to be positioned under a tiled floor type floor covering.

It is mandatory because of the standards in force in new construction or in the rehabilitation of old housing to provide acoustic insulation solutions to reduce the transmission of impact noise through the ground. There are many solutions today to meet these standard requirements.

Traditionally, sound insulation systems under tiles consist of several elements applied successively on the support to be coated. A ready-to-use adhesive is usually applied which adheres the insulation system to the substrate. It is necessary that the insulation system provides the sound reduction and the mechanical resistance. A layer of adhesive mortar is then applied to the upper part of the insulation system and is intended for bonding the tiles. Unlike under-floor acoustic systems, in tile systems, it is not necessary to install a screed, which is usually more than 25 mm thick, and the tiles are involved in the operation and performance of the system. .

Currently, two types of different acoustic sound insulation systems exist. The first system consists of rigid plates that provide both acoustic loss and mechanical strength. These plates are generally in the form of rectangle about 0.5 m ² and are ready to be directly tiled. The plates or slabs are positioned one after the other so as to cover the entire surface to be coated. Depending on the size of the part to be insulated, the necessary number of these plates can be important, and it may be necessary to cut them, resulting in an implementation that can be long and tedious for the operator. Most often, jointing strips are positioned between each plate so as to minimize the spaces that could appear between the different plates. These connections between the plates, which are consequently numerous, represent points of mechanical and, potentially, acoustic weakness. The advantage of this system is to be able to put the tile directly on the acoustic insulation. However, there is still limited use for large areas to isolate.

The second system consists of a deformable mat, preferably presenting a roll, and providing the acoustic attenuation properties. The mechanical strength is then provided by applying a mini-screed (sometimes called interposition or patching layer) on which the tile will then be laid. Conventionally, this mini-screed has a thickness of less than 10 mm. The application of the mattress makes it possible to cover a larger surface area with a single roller and in particular saves the installer time compared to systems in which a large number of plates must be placed next to each other and possibly cut them out. However, with this type of system, it is necessary to prepare the mini-screed on site, in particular by mixing a mortar composition stored in pulverulent form. This operation generates a large number of waste, can generate dust during the handling of powder bags and requires significant water consumption. In addition, because of the consistency in the fresh state of the mini-screed, more fluid than that of a tile adhesive, it is essential to provide means of jointing between the different rolls applied to the floor. From the point of view of the applicator, the manufacture of the mini-screed remains a painful task which requires, in addition to the preparation time (provision of thickness indicators and preparation of the composition of the mortar tempered) and application, a drying time of at least several hours before being able to continue laying the tiles is a waste of time.

We therefore seek to find solutions to facilitate the installation and also to reduce the waiting time between the different steps for tilers. It is within this framework that the present invention provides a system that provides acoustic insulation, and which can be positioned directly and easily under the tiles, without requiring the installation of any mini-screed. This system saves time during the installation of the system itself and therefore significantly shorten the total duration of the projects requiring the implementation of acoustic systems with a tiled finish glued.

One of the objects of the present invention is a sound insulation system in the form of a roll intended to be positioned on a support and directly under tiling. The acoustic loss and the mechanical strength are provided by a single rollable system, so easy to apply to the support to be coated and which covers a large area. This system consists of an insulating part comprising at least one flexible sub-layer providing the acoustic insulation and at least one other sub-layer providing the mechanical resistance positioned with respect to the tiles, the two sub-layers being integral with each other.

The insulation system according to the present invention makes it possible to obtain a sound attenuation equivalent to the systems currently on the market. The value of the attenuation index ALw of the impact noise, which makes it possible to characterize the impact sound insulation performance of the ground systems is between 15 and 20 dB (ISO 10140-3 standard). When one speaks of directly positioned system under-tiling, one understands that no screed or other system bringing the mechanical resistance is placed between the system of insulation according to the present invention and the tiling. However, a layer of tile adhesive that is needed to fix the tiles is applied between the insulation system and the tiles. The mechanical strength of the insulation system is tested in particular on complete systems, that is to say on systems comprising the insulation system according to the present invention on which a layer of tile adhesive was applied then the tiles by punching resistance measurements of the tiles.

The flexible underlayer consists of at least one fibrous material of mineral or synthetic origin, of the glass fiber and / or polyester fiber type or of the synthetic cellular layer type such as polyethylene or polyurethane. It is preferably made of a carded nonwoven carded thermo-bonded, needled or not needled. It can also be a nonwoven mineral obtained by molten route. It can still be a cellular material such as a synthetic foam, polyurethane foam type. For example, the flexible underlayer is a nonwoven needled polyester fibers, or a nonwoven fiberglass. The flexible underlayer may comprise several layers arranged one on the other and assembled together. For example, each of the faces of the flexible underlayer may be covered with a film, for example a polyethylene sheet, directly bonded to the nonwoven. These films are in particular present when the underlayer is a fiberglass nonwoven, in order to prevent the manipulator from being in contact with the glass fibers. This sub-layer, even consisting of several sub-layers, remains sufficiently flexible and therefore does not interfere with the windability of the complete system comprising the undercoating bringing the mechanical strength.

The sub-layer providing the integral mechanical strength of the flexible underlayer is that positioned opposite the tiles. Two types of sub-layers providing the mechanical strength necessary for the direct application of the tile according to the standards currently in force can be used in the system according to the present invention.

According to a first embodiment, the underlayer providing the mechanical strength is an underlayer based on agglomerated fibers such as vegetable fibers of the wood, hemp, rockwool or material-based mineral fibers type. synthetic composite such as synthetic fibers or synthetic resin, or based on a mixture of fibers and resin, preferably between 2 and 8 mm thick. This underlayer is therefore considered thick and relatively rigid, which makes it necessary that it be adapted to be easily rollable. It is pre-cut in the form of slats of a width of a few centimeters, typically of a width of between 2 and 5 cm. The depth of the cut is less than the total thickness of the underlayer. This cutting provides sufficient flexibility for the entire insulating system formed by the flexible underlayer and the sub-layer. more rigid layer providing the mechanical strength is rollable. The width of the slats plays a role in the final thickness of the roll: the smaller the slats, the more it is possible to have a compact roller and therefore less bulky. This underlayer may be based on composite material in the sense that at least one of the materials constituting it and mentioned above is taken from an organic resin or a mineral binder such as cement, gypsum or in a mortar. It may for example be made of needles of synthetic fibers taken in a resin.

According to a second embodiment, the underlayer providing the mechanical strength is a flexible and thin sub-layer with a thickness of less than 4 mm. It can therefore be rolled up easily without additional operation, such as pre-cuts that become necessary if the underlayer is more rigid. It can be a reinforcement veil, a reinforcing grid, in particular a glass grid. By way of example, the rigid underlayer may be a glass lattice reinforcement whose meshes are 9 × 9 mm in size.

The two sub-layers constituting the insulation system according to the present invention, that is to say the flexible underlayer and the sub-layer providing the mechanical strength, are joined together during the manufacturing process of the system according to the invention. the present invention, for example by thermal bonding and / or using an adhesive. The manner of rendering these two sub-layers integral is adapted according to the type of material of each of the layers.

The roll-up acoustic insulation system according to the present invention can also make it possible to achieve sealing, especially if the system is intended to protect water-sensitive supports. It can thus comprise, in addition to the two sub-layers constituting it, a sealing means which constitutes an additional sub-layer (also called "waterproof underlayer"). The sealing means or waterproof sub-layer is necessarily positioned above the flexible sub-layer providing the acoustic insulation. It can be positioned between the flexible underlayer and the underlayer providing the mechanical strength, especially when it is a veil or a reinforcing grid. It can also be positioned above the underlay providing mechanical strength, so just below the tiles. This means for sealing can be a sheet of synthetic material, for example polyethylene, preferably less than 2 mm thick, or even less than 1 mm. The waterproof underlayer is coupled with the acoustic insulating part. Thus, it is an integral part of the acoustic insulation system in the form of a roll and is one of the underlays of this system. It is flexible enough not to hinder the winding of the entire system. The system according to the present invention may therefore be a roll-up waterproof acoustic insulation system, which has the particular advantage of minimizing the areas of jointing to be treated after laying since it becomes possible to cover large surfaces with a single roll of the insulating and waterproof system.

The acoustic insulation system according to the invention is therefore in the form of a roller for covering an area of between 10 and 60 m ² . These rollers are easily storable. Once manufactured, they are protected in a package. Once on site, it is sufficient for the applicator to remove the package and unroll the roll on the surface to be tiled. The time saving is for him considerable, since it becomes possible to cover more than 10 m ² without the need to handle a large number of plates or apply a mini-screed.

The present invention also relates to a method of manufacturing a tiled floor on a support to be coated, characterized in that it comprises the following steps:

at. application of a ready-to-use adhesive on the support b. positioning by unwinding and gluing together, without spacing on said support, several strips of the acoustic insulating system consisting of an insulating part comprising at least one flexible sub-layer providing sound insulation and at least one other under -layer bringing the mechanical strength, the two sub-layers being integral with each other;

vs. positioning of uncoupling means on the perimeter and at the level of all the singular points emerging from the support to be coated,

d. application of a tile adhesive directly on the upper sub-layer of the acoustic insulation system and e. laying tiles.

This method of manufacturing a tiled floor on a support to be coated makes it possible to obtain an impact sound insulation assembly comprising the floor, the acoustic insulating system in the form of a roll according to the invention and the coating in the form of tiles.

The upper sub-layer of the system is the one that is furthest from the support. The upper sub-layer is the underlayer providing the mechanical strength or, when a means ensuring the tightness of the system is present, it can be the waterproof underlayer if the sealing means is positioned on the underlayer bringing mechanical strength.

Several rolls of the system according to the present invention are unwound and positioned next to each other, so as to cover the entire support to be coated.

The strips are laid so as not to leave a gap between them to limit any risk of lack of sound insulation, or sealing when the system comprises a sub-layer sealing. As in any floating acoustic system, the step of positioning the insulating layer must be followed by a step of positioning a separation means on the perimeter of the part and at all the singular points emerging from the surface to be covered. (column, pipe, etc.) to avoid acoustic bridges. These uncoupling means comprise at least one rod made of resilient materials, preferably of flexible, plastic materials. Indeed, the detaching means may comprise a single rod extending over the entire perimeter of the part to cover or several rods are put end to end to extend over the entire perimeter of the part to be covered. Such a rod is formed of two strips perpendicular to each other and made of materials to obtain an L-shaped rod. This section rod L allows to have a band, parallel to the ground plane, which comes in contact with the acoustic insulation system that is to say the assembly formed by at least one flexible sub-layer providing acoustic insulation and at least one other sub-layer providing mechanical strength. The other band of the rod, the one that is orthogonal to the ground plane, comes into contact with the wall or wall or element that defines the part to be coated. It is therefore understood that this rod acts as a buffer, joined between the layers applied to the acoustic insulation system (the adhesive and the coating) and the wall defining the part to be covered. However, the rod forming the separation means is not limited to a rod having an L shape. Indeed, this rod may comprise only one strip arranged orthogonal to the ground plane and placed between the layers applied on the acoustic insulation system and the wall delimiting the room to be covered.

The positioning step of the strips may optionally be followed by a step of positioning a jointing means at the adjoining portion of two strips positioned consecutively on the support, after step c). The seaming means is only necessary if it is necessary to treat a too important spacing between them (contrary to a conventional system, this kind of defect of application is very advantageously diminished by the rewinding of the under layer), or if the system contains a sealing layer. In general, when it is necessary to have a sealed system, all the singular points of the surface to be coated is treated before the tiling step. Singular points include curbs along walls, room angles, pipe pipes, or places where the tiles are not perfectly juxtaposed. The seaming means may be a strip that the tiler sticks at all the joined parts. If the connection is made for the sole purpose of sealing, then it can also be a liquid or putty sealant that the tiler comes to apply at the level of the contiguous parts between the different les. It is then necessary to provide a drying time of the jointing means before the tile adhesive can be applied.

If the acoustic insulation system according to the present invention does not include a waterproof underlayer integrated directly into the system, it remains possible to separate the acoustic insulation from the seal. Commonly customary sealing systems can then be applied to the acoustic insulation system according to the invention and before laying the tiles.

After the step of positioning the strips and possible means of jointing between adjacent strips, the method according to the invention comprises a step of applying a tile adhesive and then laying the tiles. The applied adhesive thickness is between 0.5 to 5 mm depending on the tool specified with the system (notched comb or half moon, etc.). The use of the acoustic insulation system according to the present invention, which provides sufficient rigidity, advantageously makes it possible to avoid having to apply a mini-screed. Depending on the acoustic system chosen, the use of certain specific glues may be recommended by the manufacturer.

Step e) of the process according to the invention is the tile laying step, which is carried out in the usual manner by the tiler. After a drying time of about 24 hours, a grout is applied between the tiles.

Other advantageous details are described below with reference to the figures illustrating the invention:

FIG. 1 represents a sectional view of a floor coated with tiles positioned on the acoustic insulation system according to the present invention in which the underlay providing the mechanical rigidity is pre-cut in the form of lamellae.

FIG. 2 represents a view of a roll of the acoustic system used on the view represented in FIG. 1.

FIG. 3 represents a sectional view of a floor coated with tiles positioned on the acoustic insulation system according to the present invention in which the underlay providing the mechanical rigidity is a supple and thin layer. Figures 4 and 4 'are top views of the insulation system used in the view shown in Figure 3. Figure 4' shows two strips placed side by side.

Figure 5 shows a view of a roll of the acoustic system shown in Figures 3 and 4.

Figures 6a, 6b, 7 and 8 are views of the disengaging means alone and arranged in an assembly formed of a tile-coated floor positioned on the acoustic insulation system according to the present invention. The sectional view shown in Figure 1 shows a floor (1) coated with tiles (4) placed directly on an acoustic insulation system according to the present invention, once unwound and placed on the support to be coated (5). This system consists of a flexible sub-layer providing the insulating acoustic insulation (2a) coupled to a sub-layer (2b-1) providing the mechanical strength. The underlayer (2b-1) shown in Figure 1 is pre-cut by notches (3) arranged at regular intervals over its entire surface. The notches (3) thus allow the insulation system shown in Figure 2 to be wound in the form of slats. The sound insulation system shown in Figure 2 comprises the two sublayers (2a) and (2b-1) associated therewith. The roll is in such a way that when the operator unrolls it, the flexible sub-layer (2a) providing the acoustic insulation is that facing the support to be coated. Fixing the acoustic insulation system according to the present invention on the support to be isolated is carried out for example by means of a C1 acrylic or vinylic adhesive applied to the support before unrolling the insulation system according to the present invention. The underlayer (2b-1) bringing the mechanical strength is, in Figure 1, the layer furthest from the support and therefore the one on which the tile adhesive C2 and then the tiles (4) will be applied. The tiles are positioned next to each other, leaving between each one a space that will be filled by a jointing mortar during the last step of the tiled floor manufacturing process.

FIG. 3 is a sectional view of a floor covered with tiles positioned on the acoustic insulation system according to the present invention. wherein the undercoating providing the mechanical rigidity (2b-2) is a flexible and thin layer, for example of the reinforcing veil or reinforcing grid. As in Figure 1, the tiles (4) are positioned directly on the undercoating providing strength (2b-2). The flexible underlayer is the one that is in contact and is bonded to the support (5) to be coated.

FIG. 4 is a view from above of the insulating system according to the present invention according to the embodiment in which the underlayer (2b-2) providing the mechanical strength is a reinforcing grid, positioned above the underlayer; flexible (2a) providing sound insulation. Figure 4 shows two strips of the insulation system according to the present invention as shown in Figure 4. The two strips are positioned side by side along the entire length (6). A strip of uncoupling, not shown in the figure can be positioned on the length (6) to make the two strips integral and limit the acoustic bridges.

Figure 5 is a representation of a roll of the acoustic insulation system according to the present invention shown in Figures 4 and 4 '. The flexible sub-layer (2a) providing the acoustic insulation is that which is directly positioned and glued against the support to be coated when the operator unrolls the roll.

The acoustic performance is evaluated for different insulation systems according to the present invention.

The value of the attenuation index ALw of the impact noise makes it possible, in particular, to characterize the sound insulation performance with the sound of impact of the ground systems (EN ISO 10140-3 and 717-2). Thus, acoustic systems known as tiling traditionally installed in this type of structure have an ALw index between 15 and 20 dB, or up to 22 dB in case of higher thicknesses of the system. As comparative examples, mention may be made of the following existing systems on the market:

- weber.sys impact insulating acoustic underlayment in the form of 8 mm thick plates ensuring both acoustic insulation and mechanical resistance since the tiles can be laid directly above. The acoustic index of this system is ALw = 20 dB (ISO 10140-3 standard).

the Lankophonic Plak system sold by Parexlanko, which is a rigid plate approximately 8 mm thick on which an additional frame is laid before laying the tile, has an acoustic reduction index of ALw = 18 dB (ISO standard 10140-3).

the Mapefonic Kit system marketed by the company Mapei is in the form of an acoustic roller glued to the support to be insulated, on which a mini-screed is applied and whose announced performance gives a weakening index of ALw = 19 dB (ISO 10140-3).

Achieving the standardized measurement for the characterization of the ALW attenuation index is cumbersome and expensive. As a result, it is reserved for limited use, mainly during the marketing of an acoustic system. As a result, techniques for calibrating acoustic performance more suitable for a screening process on a large number of systems have been implemented and validated by the acoustic community. The coupling of a calibration technique and some corresponding standardized measures allows a rigorous and inexpensive way to relatively rank the performance of a large number of systems while learning what their absolute performance levels would be. .

One of these comparative calibration techniques is to characterize the energy radiation of concrete support slabs treated by the soil systems to be characterized. The comparison of the tile treated with the reference slab concrete substrate used to ^evaluate so on the insulation to gain ol impact sound dB and thus achieve the ranking of the systems studied according to their performance. In fact, samples of dimensions around 500 x 500 mm are suspended in a free-free condition (ie suspended with tensioners or on a system of springs) and instrumentalised on the rear face with a sufficient number of accelerometers. Strikes the ^impact hammer are operated on the front face of the sample. The radiated powers are collected by the accelerometers. A post-processing of the energy sum measurements on the third octave bands of frequency 100 Hz to 3150 Hz allows to calculate the relative insulation gain δL in dB of the treated slabs relative to the support slab and by consequently the classification of the different systems. Tests performed according to the comparative calibration method described above on reference systems for which the isolation values according to the standardized method (carried out by an external certification body) are available, have made it possible to establish a clear link between the classification of the said systems according to the relative scale in ÔL and the absolute scale in A LW.

Comparative calibration tests were also performed on systems according to the present invention once covered with tiles.

The reference system (Ref system) is a system in the form of a plate, marketed under the reference weber.sys impact, which comprises an insulating layer whose flexible part is based on polyester fibers and the rigid part is a needle punch of synthetic fibers impregnated with resin.

The systems in roll and not requiring the application of a miniskip, therefore according to the present invention which have been tested are the following:

the first system tested (system 1) comprises an insulating underlayer of approximately 4 mm thick based on needle-punched polyester fibers and a rigid underlayer 3 mm thick which is a needle punch of impregnated synthetic fibers; of resin and precut in the form of slats.

the second system tested (system 2) comprises an insulating sub-layer of about 4 mm thick based on needle-punched polyester fibers and a rigid underlayer of 3 mm thick which is a needle punch of synthetic fibers impregnated with of resin and pre-cut in the form of lamellae on which has been positioned a waterproof underlay of the weber.sys type sealed above the rigid underlayer.

the third system tested (system 3) comprises a flexible insulating underlayer which is a non-woven glass mat approximately 5 mm thick and with a basis weight of 300 g / m ² . The underlay providing rigidity is identical to that of the systems 1 and 2 (needled resin-impregnated synthetic fibers, pre-cut in the form of strips, a thickness of 3 mm). A waterproof underlay of the waterproof weber.sys type is positioned above the rigid underlayer.

the fourth system tested (system 4) comprises the same flexible insulating sub-layer as that of the system 3 (a non-woven glass mat approximately 5 mm thick and with a basis weight of 300 g / m ² ), associated with a sub layer providing rigidity which is a 1 mm thick glass grid whose meshes have a dimension 9x9 mm.

the fifth system tested (system 5) is identical to the system 4 and additionally comprises a tight underlay of the waterproof weber.sys type positioned under the underlayer providing rigidity.

The results recorded in Table 1 below clearly show that the acoustic performance of the acoustic roller system according to the present invention is at least equivalent to the performance of the acoustic system in the form of plates and similar to those of acoustic systems currently used on the market for the traditional realization of this type of work with acoustic and waterproof properties.

Table 1 Punching resistance tests were carried out on a system according to the present invention. These tests are carried out for complete systems in the sense that they are carried out once the tiles have been laid. They consist in evaluating the behavior of a floor covering subjected to a depression. These tests necessary to have the technical opinion of the CSTB (Scientific and Technical Center of the Building) consist in imposing a displacement of 1 mm / min to a cylindrical punch positioned at 3 cm of a corner of a tile. The device makes it possible to draw the stress / deformation curve and the values of forces reached during the first visible incident on the curve and / or on the sample tested, as well as the breaking force, are recorded. Measurements were made 16 hours after laying the tiles on the system 4 for which the rigid layer is a sheet of glass plate. The value of the breaking force for the system 4 according to the present invention is 1 kN, which is in accordance with the CSTB requirement.

In FIGS. 6a, 6b, 7 and 8, the uncoupling means arranged on the perimeter of the part and at the level of all the singular points emerging from the surface to be covered are represented. These uncoupling means comprise at least one strip 6 made of resilient materials, preferably of flexible, plastic materials. Indeed, the detaching means may comprise a single rod extending over the entire perimeter of the part to cover or several rods are put end to end to extend over the entire perimeter of the part to be covered. Such a rod 6 is formed of two strips 6a, 6b perpendicular to each other and made of materials to obtain a rod section L. This section L-shaped rod allows to have a strip 6a, parallel to the plane of the ground, which comes into contact with the sound insulation system that is to say the assembly formed by at least one flexible sub-layer providing the acoustic insulation and at least one other sub-layer providing the mechanical strength . The other band 6b of the rod, the one that is orthogonal to the ground plane, comes into contact with the wall or wall or element which defines the part to be coated. It is therefore understood that this rod acts as a buffer, joined between the layers applied to the acoustic insulation system (the adhesive and the coating) and the wall defining the part to be covered. However, the rod forming the separation means is not limited to a rod having an L shape. In fact, this rod may comprise only one strip arranged orthogonal to the ground plane and placed between the layers applied on the acoustic insulation system and the wall delimiting the room to be covered.

Claims

A method of manufacturing a tiled floor on a support (5) to be coated, characterized in that it comprises the following steps:

at. application of a glue (C1) ready for use on the support b. positioning by unwinding and gluing together, without spacing on said support, several strips of the acoustic insulation system consisting of an insulating part comprising at least one flexible sub-layer (2a) providing acoustic insulation and at least another underlayer (2b-1, 2b-2) providing the mechanical strength, the two sub-layers being integral with each other;

vs. positioning of uncoupling means (6) on the perimeter and at all the singular points emerging from the support to be coated,

d. application of a tile adhesive (C2) directly on the upper sub-layer of the acoustic insulation system and

e. laying tiles

(4).

A method according to claim 1, characterized in that a jointing means is positioned at the contiguous portion of two strips positioned consecutively on the support, after step c).

Method according to one of the preceding claims, characterized in that the flexible sub-layer (2a) consists of at least one fibrous material of mineral or synthetic origin, of the glass fiber and / or polyester fibers type or type synthetic honeycomb layer such as polyethylene or polyurethane.

Method according to the preceding claim, characterized in that the flexible underlayer (2a) consists of a carded nonwoven carded thermo-bonded, needled or not needled.

5. Method according to one of claims 3 or 4, characterized in that the flexible sub-torque (2a) comprises a plurality of layers disposed on each other and assembled together.

6. Method according to one of the preceding claims, characterized in that the sub-layer (2b-1) providing the mechanical strength is an underlayer based on agglomerated fibers such as vegetable fibers of the wood type, hemp, mineral fibers of the rock wool type, or based on a synthetic composite material such as synthetic fibers or synthetic resin, or based on a mixture of fibers and resin, with a thickness preferably of between 2 and 8 mm.

7. Method according to the preceding claim, characterized in that the sub-layer (2b-1) providing the mechanical strength is pre-cut into strips.

8. Method according to one of claims 1 to 6, characterized in that the sub-layer (2b-2) providing the mechanical strength is a flexible and thin sub-layer with a thickness of less than 4 mm.

9. Method according to the preceding claim, characterized in that the sub-layer (2b-2) providing the mechanical rigidity is a reinforcing web, a reinforcing grid, in particular a glass grid.

10. Method according to one of the preceding claims, characterized in that it further comprises a sub-layer providing sealing.

1 1. Method according to claim 10, characterized in that the waterproof sub-layer is positioned above the flexible sub-layer providing the acoustic insulation.

12. Method according to one of claims 10 or 1 1, characterized in that the waterproof sub-layer is positioned between the flexible sub-layer (2a) providing the acoustic insulation and the underlayer (2b-1, 2b-2) bringing the mechanical strength either above the underlayer (2b-1, 2b-2) bringing the mechanical strength and under the tiles.

13. Method according to one of claims 10 to 12 characterized in that the waterproof underlayer is a sheet of synthetic material such as polyethylene, coated on each side with a nonwoven material such as a non-woven polypropylene fiber, said sheet having a thickness of less than 2 mm, or even less than 1 mm.

14. Method according to one of the preceding claims, characterized in that the uncoupling means comprise at least one rod formed of two strips perpendicular to each other and made of materials to obtain a section of rod L.

15. Method according to one of the preceding claims, characterized in that said at least one rod is made of a resilient material.

16. Method according to one of the preceding claims, characterized in that the securing means comprise a single rod extending over the entire perimeter of the surface to be covered.

17. Method according to one of the preceding claims, characterized in that the securing means comprise at least two rods arranged side by side to extend over the entire perimeter of the surface to be covered.