DK2525016T3 - Bygningsydervæg made of high density stone wool - Google Patents

Description

Description

The present invention relates to an outer wall of a building of the type with a render finish.

This applies equally to non-industrial buildings, industrial buildings, the external renovation/insulation of buildings with stone or brick outer walls, or concrete outer walls, whether solid or lightweight, or the erection of wood-framed buildings, etc.

In order to have a fa$ade with a render finish, the most commonplace techniques are to use: a stonework supporting wall covered with render insulation from the outside, made up of dense (foam or rock wool) panels to which renders are directly applied cement sheets supporting render.

If the external facades are insulated using lightweight flexible rock wool (for example in order to make it easier to pass cables or pipes therethrough, or in order to avoid having to repair the supporting wall), no render can be applied directly to the rock wool. A render support sheet is required.

In wood-framed homes, the rock wool is placed between studs and an exterior panel is added to provide the home with mechanical stability (this being referred to as a cross-bracing panel). This panel may be made of wood (OSB - oriented strand board) or of fibre-cement.

For wood-framed homes, it is impossible to apply render directly to the wood. In order to apply render it is possible to staple a rain barrier (that blocks out liquid water but allows water vapour through) to the OSB, then to attach a three-dimensional mesh (described in Patent Application US 2010/0000665) attached to the OSB panel. The three-dimensional structure of the mesh makes it easier for the render to be applied. The three-dimensional mesh may be replaced by a thick alkali-resistant metal mesh, conventionally used in renovating stonework. Spacers are then needed in order to ensure that the mesh lies within the render rather than being flat against the supporting wall.

For wood-framed homes or facades it is possible to use sheets of cement (for example of the type marketed under the registered trade mark Aquaroc® by the company Gyproc), covered in render.

It is also possible to attach a thin metal latticework as described in Patent Application FR 2769033 to the framework and to cover this with render. See also DE 100 08 748 Al.

These solutions present problems on the building site: sheets of OSB or sheets of cement are heavy to handle (~ 13 kg/m2 or more); if the OSB becomes wet with rainwater before the rain barrier is applied and the mesh is attached, the tensile strength of the screwed assembly holding the mesh in place will be greatly reduced; cement sheets swell with moisture (generally between 0.7 and 1 mm/m) and this applies stress to the joints between the sheets. A special treatment of the joints is required, using mortar and a double reinforcing mesh. With an expensive elastic organic render (of a thickness limited to a few mm), it is possible to avoid cracks, but a ripple effect is generally visible. With a cement-based mineral render (which is far less expensive than an organic render) it is very difficult to avoid cracks, because mineral based renders crack more readily in the event of repeat stresses. As a result, cement sheet manufacturers are forced to make their sheets water repellent in order to limit dimensional variations, and this leads to a not insignificant increase in the cost of manufacture; in the case of the metal latticework, a thick first layer of render needs to be applied in order to make the structure more rigid, and then it is necessary to wait at least one week for drying out, before applying a thick second coat of render before once again waiting at least one week before applying the finish coat, something which is time-consuming. In addition, the moisture generated by the render as it dries out is partially absorbed by the wood, leading to dimensional variations and increased risks of cracking. In the case of wood-framed homes, the latticework cannot be used for the cross-bracing because it is too flexible; in all cases (OSB, cement sheets, metal latticework), it often happens that the supporting wood is wet at the time of application (after a rainfall), whether this is in the case of a home with a wooden framework or wooden cladding in the case of ventilated fa9ades. As the wood dries out it shrinks, leading to significant dimensional variations of the support. No sheet or render is then able to withstand the dimensional variations, leading to cracks in the render. The same situation may arise in the reverse scenario, namely when the wood is dry at the time of application then swells as a result of poor treatment of an individual point with the ingress of water into the fa9ade, something which once again leads to cracking. The solutions set out previously therefore demand that the wood be initially perfectly dry and protected against rainfall on the building site for weeks. Particular attention needs to be paid to the individual points (window edges, etc.) where the slightest ingress of water into the framework causes cracks in the render.

The inventors have looked for a way of reliably and durably using a conventional inelastic cement-based render either on low-cost cement sheets that exhibit a large amount (up to 2.5 mm/m) of dimensional variation with moisture or on sheets fixed to a wooden framework that may move with moisture.

The invention has been able to achieve this objective and therefore has as subject a building outer wall comprising a rock wool panel with a density of at least 40 kg/m3 covered by a three-dimensional mesh structure, by way of support for render, the mesh being held by fixings passing through the rock wool.

According to the invention, a three-dimensional mesh structure may be made up of a three-dimensional mesh or of a two-dimensional mesh and of a set of spacers in a third dimension.

The rock wool interposed between, on the one hand, the render and, on the other hand, the structure of the building, such as the wooden framework bearing structure or OSB or fibre-cement sheet render supporting structure, all liable to deform according to atmospheric conditions, is elastic enough to withstand all the dimensional variations.

Advantageously, the rock wool exhibits no dimensional variation with water, or with thermal shock; treating the joints then becomes needless, hence saving time on the building site. Rock wool is lightweight: conventional dense panels 15 mm in thickness have a mass per unit area of approximately 2 to 3 kg/m2 as compared with 13 kg/m2 for cement sheets. In addition, the insulating nature of the wool protects the structure of the building, notably the support sheets (OSB, cement, etc.) and improves the durability thereof.

The interface between the mortar of which the render is made and the insulation exhibits adhesion between the two materials. An insulating material other than rock wool (for example foams) may be used, but foams have markedly higher shear strength than rock wool (50 kPa for expanded polystyrene as compared with 1 kPa for non-creped rock wool), which means that the stresses at the mortar/insulation interface are higher with foams. In the case of rock wools, the mortar can move freely without stressing the support in shear, thus greatly reducing the risk of cracking. The same is true of the framework which can move without introducing stresses into the rock wool, and therefore into the render. The low shear strength (1 kPa) of the rock wool is nevertheless markedly higher than the shear due to the weight of the heaviest renders (0.5 kPa), which therefore presents no risk.

Non-creped rock wools nevertheless have the disadvantage of having a very low tensile strength (< 1 kPa), which means that it is not recommended for a render to be applied directly without the risk of delamination in the event of high winds. In order to ensure durable mechanical integrity of render applied to this type of rock wool, a three-dimensional mesh structure is placed on the rock wool, through which it is fixed to the underlying structure; it may preferably be fixed also to the rock wool.

This mesh structure comprises a mesh, notably made of glass, metal or some other material resistant to the render.

According to one embodiment, this may be a three-dimensional mesh formed from a glass fabric, as described in the aforementioned Patent Application US 2010/0000665 or in WO 2005/060691, each incorporated by reference, which is placed on the rock wool and anchored into the outer wall by screws that pass through the rock wool. The three-dimensional structure of the mesh allows a simple and rapid application of render. The three-dimensional glass mesh comprises weft and/or warp filaments that are wavy, which means to say that a filament follows a curved path, for example in the shape of a C or an S, notably a sinusoidal path, between the points of crossing with two successive filaments of the woven network, respectively weft or warp filaments. Its thickness is advantageously at least around 5 mm. Its filaments are partially or almost entirely made up of glass fibres. It is coated with resin of the polyvinyl, epoxy, polyester, styrene latex or acrylic type, or the equivalent which is resistant to the render.

In another embodiment, the three-dimensional glass mesh is replaced by a two-dimensional mesh, generally alkali resistant metallic, associated with spacers which hold the mesh away from the rock wool by an approximate distance of 5 mm. The metal mesh is also held by fixings passing through the rock wool, which may be anchored into the underlying structure, the bearing structure of the building and/or the render supporting structure.

However, a glass mesh is preferred because it is more lightweight, carrying no risk of corrosion or of injury during cutting and fitting.

The thickness of the rock wool panel is preferably at most equal to 25, more particularly preferably 20 mm, and at least equal to 5 mm.

Within this range of thicknesses, the rock wool panel acts as a resilient layer capable of accommodating the relative movements of the components of the outer wall.

According to one main first embodiment of the invention, the outer wall comprises a cross-bracing panel, such as a panel made of wood, notably OSB, or fibre-cement, fixed to a supporting wall or a framework forming part of the outer wall. The framework in this instance is made of metal, wood, composite such as a polymer containing reinforcing, fire retardant or other fillers, for a ventilated fafade. These may be uprights of a wood-framed building.

The rock wool panel and the mesh are then preferably fixed, by distinct or identical means, to the cross-bracing panel. These fixing means are conventional, of the screw type, of suitable shape and size.

Furthermore, the mesh, and also the rock wool panel where applicable, may advantageously be fixed, by distinct or identical means, to a supporting wall or a framework forming part of the outer wall. These fixing means may be associated with plugs in a supporting wall in particular. They may constitute the only fixing of the glass mesh and/or of the dense rock wool panel to the outer wall, or may combine with their fixing to the cross-bracing panel so as to improve the mechanical strength of the assembly. Finally, single means of fixing the glass mesh and the rock wool panel to the supporting wall or framework and to the cross-bracing panel may be used.

In this first main embodiment of the outer wall of the invention, the density of the rock wool panel is preferably comprised between 80 and 200 kg/m3.

According to a second main embodiment of the outer wall of the invention, the density of the rock wool panel is at least equal to 120, preferably 160 and particularly preferably 200 kg/m3, and the rock wool panel is fixed to a supporting wall or a framework forming part of the outer wall. The dense rock wool panel may then constitute the only cross-bracing panel of the exterior outer wall of the building. This then makes available means for replacing the heavy cement sheets that experience dimensional variations, with very dense glass wool sheets with the mesh anchored into a supporting wall or a framework. The render makes the surface rigid. This method makes it possible to save a step in laying (thereby saving time on the building site). In addition, in the case of a non-ventilated fa9ade, the cement sheets exhibit a risk in terms of moisture management, because the diffusion of water vapour is very low. By contrast, rock wools are 100 to 150 times more breathable than cement sheet, something which correspondingly reduces the risks of problems arising if water infiltrates into the non-ventilated fa9ade. It is therefore possible to combine these dense rock wool sheets with lightweight rock wool external insulation without the need to provide ventilation, for example using fixings such as those described in Patent Application EP 2 194 209. That allows a significant time saving, since the application of conventional ventilated fa9ades known to those skilled in the art is a relatively lengthy and complex process (determining the layout of fixings, which means to say calculating the number of fixings to be used and where exactly they will be positioned on the fa9ade, laying the framework, laying and cutting the insulation, adjusting the framework, laying the sheets of facing, etc.).

The density of the said rock wool panel is then preferably at most 300 kg/m3.

The render support mesh is then preferably fixed to a supporting wall or to a framework that forms part of the outer wall, by fixing means identical to or different from those of the dense rock wool panel.

According to two preferred features of the outer wall of the invention: the rock wool panel directly or indirectly covers another thickness of rock wool; this other thickness may be made up of a wool that is less dense or relatively low-density, for example placed between uprights constituting a wooden framework of a building; the indirect coverage here refers to there being some other material, for example a cross-bracing panel made of a material other than dense rock wool, particularly made of OSB or cement sheet, being interposed between them; the rock wool panel directly or indirectly covers an air space, notably a ventilated air space.

Other subjects of the invention are: a wood-framed building comprising an outer wall described hereinabove; a ventilated fa$ade comprising such an outer wall; lining with external insulation comprising such an outer wall; and a rock wool panel that can be incorporated into such an outer wall and that comprises on one side a three-dimensional mesh structure attached to the wool by a mechanical and/or adhesive means.

The invention is now illustrated by the attached drawings in which

Figure 1 schematically depicts the first main embodiment of the outer wall of the invention, in the case of a wood-framed home;

Figure 2 depicts an analogous construction in the event of deformation of the cross-bracing sheet;

Figure 3 depicts the first main embodiment of the outer wall in the case of a supporting wall made of brick;

Figure 4 depicts a construction that differs from that of Figure 3 in the creation of a ventilated air space;

Figures 5 and 6 schematically depict the second main embodiment of the building outer wall in the case of a supporting wall made of bricks respectively without and with a ventilated air space;

Figure 7 is a partial depiction of the second main embodiment of the outer wall according to the invention in the case of a ventilated fa?ade with a wooden framework; and

Figure 8 reproduces Figure 7 in the case of deformation of the wooden framework.

As shown in Figure 1, the wooden framework of a home comprises wooden uprights 6 between which a thermal and acoustic insulation glass wool 16 of relatively low density (< 55 kg/m3) is held.

The uprights 6 and the relatively low-density glass wool 16 are covered by a cross-bracing panel 4 able to give the assembly the required mechanical strength both in terms of tension (horizontal loading, stresses resulting from the wind in particular) and in shear (vertical load, the weight of the constituent parts of the outer wall). This is an OSB (oriented strand board) panel covered with a rain barrier (impervious to liquid water for example by means of a suitable film of breathable polymer) or a sheet of fibre-cement.

The cross-bracing panel 4 is covered by a dense glass wool panel 1 that is 15 mm thick, then by a layer of render 3 that is 10 mm thick formed in a three-dimensional glass mesh 2 which constitutes a support therefor. The three-dimensional glass mesh 2 is in accordance with the teachings of Patent Application US 2010/0000665. It comprises wavy weft (and respectively warp) filaments between two successive warp (or respectively weft) filaments, notably in the shape of a C or an S between these two filaments. This waviness defines a thickness of at least 5 mm. Its filaments are made of glass fibre. It is coated with poly(vinyl chloride) resin which is resistant to the render. The three-dimensional glass mesh 2 is in the middle of the render 3, which is in adhesion with respect to the dense glass wool panel 1.

The assembly thus formed of the cross-bracing panel 4, of the dense glass wool panel 1, of the three-dimensional glass mesh 2 and of the render 3 is fixed to the uprights 6 by screws 8. All of the screws, in this figure and the subsequent figures, are associated with washers 19.

In Figure 2, the four constituent parts 4, 1, 2 and 3 of this assembly are fixed together by screws 7 and the cross-bracing panel 4 is screwed to the uprights 6 by screws 9. This figure schematically shows that the dense glass wool panel 1 is able, because of its compressibility, to compensate for the deformation of the cross-bracing panel 4 caused by its swelling with moisture, thus making it possible to avoid the formation of cracks or any unevenness on the surface of the outer wall. The same deformation could equally have been depicted in a structure strictly identical to that of Figure 1.

The cross-bracing panel 4 of Figure 3 is depicted without deformation. Moreover, the outer wall here differs from that of Figure 2 by the fixing of the cross-bracing panel 4 to a supporting wall made of brick 5, rather than to wooden studs. The cross-bracing panel 4 is screwed by screws 18 into piles 20 secured to the supporting wall 5. It is the renovation and/or the lining with insulation from the outside of the supporting wall 5 that is depicted here.

The construction in Figure 4 differs from that of Figure 5 through the arrangement, between the relatively low-density glass wool 16 and the crossbracing panel 4, of a ventilated air space 17. This arrangement entails adapting the way in which the cross-bracing panel 4 is fixed to the supporting wall 5 using angle brackets 10 which are fixed into the supporting wall using screws and plugs that have not been depicted, to which wooden studs 11 holding the glass wool 16 are fixed, the studs 11 themselves being fixed to the cross-bracing panel 4 by screws 12.

In the outer walls of Figures 5 et seq. the dense glass wool panel 1 takes the place of a single cross-bracing panel. The density of the panel 1 is comprised between 200 and 300 kg/m3. In Figure 5, the dense glass wool panel 1, the three-dimensional glass mesh 2 and the render 3 are fixed to one another by auxiliary fixing means 13 such as screws. They are also fixed together to the supporting wall 5 by the same fixing screws 8 in piles 20 secured to the supporting wall 5. The piles 20 pass through the thickness of low-density glass wool 16 and a superficial part of the supporting wall 5. No ventilated air space is provided. The render 3 used here can be chosen to have a certain degree of breathability with respect to the moisture likely to be exchanged between the inside and the outside of the building, and vice versa, through the seasons, thus enjoying the same breathability property of the glass wool 16 and 1.

The construction of Figure 6 differs from that of Figure 5 through the creation of a ventilated air space 17 between the low-density wool 16 and the dense wool 1. This arrangement has entailed adapting the fixing of the dense glass wool panel 1 to the supporting wall 5 in a way comparable to the adaptation depicted in Figure 4. In practice, the dense glass wool panel 1 and the three-dimensional glass mesh 2 (and therefore the render 3) are here fixed together to the studs 11 by single fixing means 14 such as screws.

Figures 7 and 8 are partial schematic depictions of the second main embodiment of the outer wall of the invention, in which the dense glass wool panel 1, the three-dimensional glass mesh 2 and the render 3 are fixed together to the wooden studs 11 (60 mm x 80 mm) of the framework of a ventilated fa£ade using single screws with mobile heads 15. The mobility of the screw heads can readily be obtained by combining a conventional screw with a stainless metal washer 19. The thickness of the studs 11 describes a ventilated air volume 17. The studs 11 are fixed to a stonework supporting wall, not depicted, by means of metal lugs, not depicted (after the manner of the embodiments shown in Figures 4 and 6).

When moisture is present, the studs 11 deform (Figure 8). This deformation is compensated for by the mobile heads of the screws 15 and the deformation of the dense glass wool panel 1 so that no visible impairment can be observed at the surface of the render 3.

The same effects are achieved by replacing, in Figures 7 and 8, the studs 11 of a ventilated-fa9ade wooden framework with the uprights (60 mm x 140 mm) of a wood-framed home, and the ventilated air volume 17 with another thickness of rock wool, in particular relatively low-density rock wool, placed between the uprights.

Claims (25)

3 A building exterior wall comprising a mineral wool panel (1) having a density of at least 40 kg / m3 covered by a three-dimensional grid structure (2) in support of plaster (3), wherein the grid (2) is held by fasteners (7, 8, 14, 15) passing through the mineral wool (1). A wall according to claim 1, characterized in that the three-dimensional grid structure consists of a three-dimensional grid or two two-dimensional grids and a set of spacers arranged in a third dimension. Wall according to claim 1 or 2, characterized in that the grid (2) is three-dimensional and is formed of glass tissue. Wall according to claim 3, characterized in that the grating comprises shot and / or warp threads, which are corrugated, for example C-shaped or S-shaped, and in particular sinusoidal, between the intersection points with two successive strands, respectively shot or warp threads. , in the woven network. Wall according to claim 1 or 2, characterized in that the grating (2) is an alkali-resistant metal and is combined with spacers. Wall according to any one of claims 1 to 5, characterized in that the grating is attached to the underlying structure of the wall on one side by means of the fasteners passing through the mineral wool and on the other hand it is fixed to mineral wool using additional mechanical and / or adhesive fasteners. Wall according to one of the preceding claims, characterized in that the thickness of the mineral wool panel (1) is at most 25 and preferably 20 mm. Wall according to one of the preceding claims, characterized in that the thickness of the mineral wool panel (1) is at least 5 mm. Wall according to one of the preceding claims, characterized in that it comprises a cross-stiffening panel (4), such as a panel made of wood, in particular OSB, or of fiber cement attached to a wall (5) or a skeleton (6). ) that is part of the outer wall. Wall according to claim 9, characterized in that the mineral wool panel (1) increases the lattice (2) is attached to the cross-stiffening panel (4) by the same or different means (7). Wall according to one of claims 9 and 10, characterized in that the grating (2) and, where applicable, the mineral wool panel (1) is attached to a wall (5) or a skeleton (6) which is a part of the wall, using the same or different means (8). Wall according to one of the preceding claims, characterized in that the density of the mineral wool panel (1) is between 80 and 200 kg / m '. Wall according to one of claims 1 to 8, characterized in that the density of the mineral wool panel (1) is at least equal to 120, preferably 160 and even more preferably 200 kg / n, and in that the mineral wool panel (1) is attached to a wall (5) or a skeleton (6) which is part of the wall. Wall according to claim 13, characterized in that the density of the mineral wool panel (1) is at most 300 kg / no. Wall according to one of claims 13 and 14, characterized in that the grating (2) is attached to a wall (5) or a partition (6) which is part of the outer wall. Wall according to one of the preceding claims, characterized in that the mineral wool panel (1) covers a different thickness of mineral wool (16) directly or indirectly. Wall according to one of the preceding claims, characterized in that the mineral wool panel (1) covers a different thickness an air space (17) directly or indirectly, in particular a ventilated air space. A threshold housing comprising an outer wall according to one of the preceding claims. Ventilated facade comprising an outer wall according to one of claims 1 to 17. Exterior of the soldering comprising an outer wall according to any one of claims 1 to 17. Mineral wool panel (1), which can be built into a wall according to any one of claims 1 to 17, characterized in that the panel comprises on one side a three-dimensional grid structure (2) fixed to the wool by mechanical and / or adhesive. agents. Panel according to claim 21, characterized in that the three-dimensional grid structure consists of a three-dimensional grid or two two-dimensional grids and a set of spacers arranged in a third dimension. Panel according to claim 21 or 22, characterized in that the grating is three-dimensional and is formed of glass tissue. Panel according to claim 23, characterized in that the grating comprises shot and / or warp threads which are wavy, for example C-shaped or S-shaped, and in particular sinusoidal, between the intersection points with two successive strands, respectively. or warp threads, in the woven network. Panel according to claim 21 or 22, characterized in that the grating (2) is an alkali-resistant metal and is combined with spacers.