EP1395719B1 - Flat or flat inclined roof construction and associated insulating element - Google Patents

Abstract

The invention relates to a flat and/or flatly inclined roof construction, consisting of a lower structure carrying a heat insulating element and/or sound insulating element, especially consisting of mineral fibre insulating boards, said insulating element being partly arranged on upper chords of the carrier elements forming the lower structure. Said roof construction also comprises an upper structure, the lower structure and/or the upper structure forming carrier elements consisting of individual profiled sheets. The aim of the invention is to create a roof construction without the cited disadvantages, providing insulation which is more easily and more reliably accessible, at least during the construction phase, and which has a low total weight and high insulating power. To this end, the insulation (2) consists of at least two layers, at least one (14) of said layers, i.e. at least the layer (14) on the lower structure (1), being embodied in a tension-resistant manner.

Description

The invention relates to a roof construction in a flat and / or flat inclined configuration, consisting of a substructure on which a thermal and / or acoustic insulation, in particular of insulating panels of mineral fiber insulation, preferably of glass and / or stone fibers, part of the surface on top chords of the substructure forming trays and a superstructure, with lower and / or top construction as trays made of individual profiled sheets. The invention further relates to an insulating element for a roof construction in a flat and / or flat inclined configuration, in the form of an insulating panel of mineral fibers, preferably of glass and / or stone fibers, the part of the surface rests in the installed state on upper chords of a substructure, wherein the insulation board two parallel to each other extending and spaced apart large surfaces, two connecting the large surfaces, formed at right angles to the large surfaces and parallel to each other extending longitudinal sides and to the longitudinal sides and the large surfaces arranged at right angles narrow sides.

Flat or flat inclined roof structures of hall-like buildings very often consist of a support shell of profiled steel sheets from which the substructure, but often also the roofing is formed. In order to achieve the largest possible spans at low sheet thicknesses designed as profiles steel sheets are used with relatively high height and average width. In doing so, certain deflections resulting from the dead loads and when walking or driving, that is to say from dynamic loads, are accepted. The clearances between the upper belts formed by the profiling vary between about 130 mm and about 175 mm. In contrast, the widths of the upper straps are significantly lower at approx. 108 mm to approx. 145 mm.

In order to keep the costs for the substructure low, the profiles are laid with large spans. Since the connection of the individual profiles with each other also takes place only pointwise, there is a vibratory membrane that can already be excited by small forces.

For thermal insulation and as a fire protection overlay on this relatively unstable substructure, in particular elastic-resilient insulating materials made of mineral fibers, proven in particular from rock wool. On the one hand, these insulating materials can follow the movements of the substructure, on the other hand they can still have a damping effect if they only rest loosely on the substructure. Further advantages of these insulating materials are the non-combustibility in terms of DIN 4102, the high sound absorption capacity and the economic efficiency of their production and processing. In order to improve the structural behavior of the insulating materials and at the same time to increase the laying speed, the insulation materials are preferably delivered as large-sized insulation boards, for example, with the dimensions of about 2 mx 1.2 m site site and laid. But there are also areas of application for conventional, contrast, small-sized insulation board known. Since the dimensions of the insulating materials, especially the insulation boards are not regularly matched to the dimensions of the trays, namely the distance of the upper straps, thereby reducing the specific number of cantilevered and thus particularly easy to damage insulation boards or sections of insulation, the web-shaped be trained and relocated.

A conventional roof construction in a flat and / or flat inclined configuration thus consists of a profiled sheet metal tray, a loosely laid polyethylene film as a vapor barrier air barrier, between about 50 - 160 mm thick thermal barrier coating and a cover made of plastic films, synthetic rubber or bituminous membranes , which are fixed point by point by screws screwed into the tray. In order to distribute the tensile force of the screws in accordance with the material, sheet metal plates are used, which press the seals against the insulating material.

Roof constructions constructed in this way constitute "unused roofs" in the sense of the specialist rules of the roofing trade, whereas terraces or parking areas are to be regarded as used roof constructions. Under use is therefore an unlimited walking and driving as well as the parking of containers, goods, etc. or the setting up of scaffolding, ladders to understand.

Even with unused roof structures in the sense of the above definition, there is already one in the construction of the roof construction punctual and / or large-scale loading of the roof construction by persons working on the roof during construction and / or machines and equipment set up there. Due to a poor management of the succession of activities in the roof area or on the roof surfaces and a negligent handling of their own work, the finished roofs are used as flat, easy to walk on and to be traveled surfaces, traffic and storage areas, the insulation materials repeatedly subjected to very high mechanical stresses that lead to damage to the structure and consequently to a defective work.

In order to achieve a higher compressive strength and a higher resistance to walking and driving with trolleys or trolleys during the construction phase of the building or the roof construction, including any structures, the structure of the insulating materials has been significantly changed in recent years in such a way that the individual fibers are arranged in a relatively steep storage to the large surfaces of the insulating materials, in particular the insulation boards or insulating material webs. Technically, this is done in the production of insulating materials by longitudinal and vertical compression of impregnated with binders fiber mass and subsequent fixation of the highly deformed fiber mass by the curing of the most commonly used thermosetting resins or resin mixtures. The longitudinal / vertical compression is usually in the direction of production, so that the fibers are steep in the direction of production and strongly deformed and stored transversely to the production direction flat.

The bending tensile strength of an insulating board produced from such insulation sheet is therefore about 3 to 6 times higher than in the production direction, depending on the density in the examination transverse to the production direction. To avoid a too early collapse of the structure, the insulation boards must always be designed so that the insulation board axis is arranged with the higher bending tensile strength transverse to the upper chords. As a result, the fundamental problems are not eliminated, but only mitigated.

Compared to the bending tensile strength, the compressive stress increases very clearly, so that regularly the average density of the insulating materials, in particular the insulation boards can be reduced. This density is in insulating boards with this structure in the range of about 130 to 180 kg / m ³ . The commercial insulation boards are offered with average compressive stresses of about 55 to 70 kPa, with a ten percent compression of the insulation board is permitted. This information applies only to unused samples. The values represent a maximum value that can be achieved once, because structural changes already occur below this limit. Therefore, even with a gentle treatment of the insulating layer during the construction period regularly loss of strength in the order of about 20 to 35 kPa on. The resulting compressive strength is then the relatively stable output level for the actual use phase of the building or the life of the flat roof construction again.

A disadvantage is the heat insulation in such a structured insulation boards by about 2 to 3 mW / mK increased thermal conductivity, so that these insulation boards often fall into the heat conductivity group 045 according to DIN 4108.

The surface of such insulation boards is very sensitive to shearing loads by walking or driving. This disadvantage is due to the in the DE 37 01 592 C1 and the EP 0 277 500 B1 described insulation panels avoided. These insulation boards have an integrated, highly compressed zone in which the individual fibers are pressed together to densities of about 160 to 220 kg / m ³ and thereby brought into a horizontal position.

The roof insulation panels as well as the sloping roof elements are protected by loosely laid insulation boards with thicknesses of approx. 20 - 50 mm.

The resistance of the surface of such trained insulation boards is by gluing of woven glass, plastic or natural fibers or glass webs using rel. thick layers of tough plastic adhesive, such as bitumen or the like achieved. However, such cover layers lead to the classification of the insulating board as a combustible building material, resulting in significant economic disadvantages as long as the area of application of the insulation boards is sustainably influenced.

For example, rigid concrete slabs of approx. 20 to 50 mm in thickness or large-format light grids laid on rubber mats, which are laid on the roof seal, offer the best protection for the insulation. However, these procedures lead to high roof weights and thus expensive wall constructions, whereby the costs are increased, especially in the industrial construction sector.

Starting from this prior art, the invention has for its object to provide a roof structure and an insulating element with which or to which the foregoing disadvantages are avoided and with the or the one better at least during the preparation and safe walk-insulation at low overall weight and high insulation performance is created.

The solution of this problem provides for a generic roof construction that the insulation consists of at least two layers, of which at least one layer, namely at least the layer resting on the substructure layer is formed tensile strength.

To solve the task is provided in an insulation element according to the invention that the insulation board consists of at least two layers, of which at least one layer, namely at least the resting on the substructure or another edition layer is formed tensile strength and that the mineral fibers in the narrow sides of a flat orientation relative to the large surfaces and in the region of the longitudinal sides have a steep orientation relative to or large surfaces.

The roof construction according to the invention thus provides for the installation of an insulating material, which does not tend by the tensile structure facing the substructure, under load by walking and / or storage of objects, in particular punctual loads are in the foreground to bend between the upper straps. In such loads are with the the roof construction of the invention avoided both bending cracks, as well as shear stresses.

To take into account here are the occurring static and dynamic loads of the roof construction, in which the insulation, in particular the individual insulation boards rest only part of the surface on the upper chords of the trays. Insulating boards with a small material thickness are mainly loaded on bending and tension. For larger material thicknesses, especially the shear stress is in the foreground, i. the loaded volume element above the area between two adjacent upper chords of the tray is pushed under load. In conventional insulation boards with a steep orientation of the mineral fibers to the surfaces, the types of stress occurring in a conventional manner in combination also reduce the directional dependence of the bending tensile strength. But in order to make the generally low bending tensile strength in the direction of production of the insulating material less effective, the material thickness of the insulating material must be significantly increased. Such an approach is precluded by economic reasons. Furthermore, often determines the desire to form the insulation of more, at least two layers laid with offset joints insulation boards, the material thickness of the individual insulation boards or layers of insulation, as far as, for example, sheet-like insulation material is laid. Since, however, does not arise in the superimposition of the individual, in the surfaces also profiled insulation boards a non-positive bond between the layers of insulation, the individual insulation board reacts individually with deformations to the loads occurring in each case.

These disadvantages are avoided in the roof construction according to the invention and the insulation element according to the invention, that the supporting behavior of the insulation, in particular the insulating elements, preferably the insulation boards is significantly improved by at least one tensile layer in the region of the substructure facing large surface of the insulation, in particular of the insulating element , Preferably, the insulation boards is provided. In a multi-layer insulation, the design of the insulation with a tensile layer on the resting on the substructure Be limited to the location of the insulation. However, it has proven to be advantageous to also form further layers with an insulating element which has a tensile layer in accordance with the invention.

The tensile layer may be formed integrally with the one or more layers of the insulating element. Alternatively or additionally, a tensile layer may also be formed as a separately manageable element, which is adhered in a further process step to the other layers of the insulating element.

The tensile layer preferably consists of at least one tear-resistant fabric, in particular a mesh fabric made of glass, plastic and / or textile fibers. In the same way as an alternative or as an additional reinforcement glass fleeces are suitable, preferably glass fleeces with a thread reinforcement.

In an improved and preferred embodiment, the individual mineral fibers are bonded in an area near the surface of a few millimeters up to 5 cm of the insulation elements forming the insulation with an additional binder. This is therefore an increase in the binder content in the near-surface region, wherein the additional binder in this area with the binder of the insulation, namely the insulating element match or may deviate therefrom. The binder may have an adhesive effect both with respect to the mineral fibers of the insulating element and with respect to the additionally applied tensile layer.

According to a further feature of the invention, it is provided that the mesh fabric is pressed before curing of the binder in an impregnated with preferably additional binder endless mineral fiber web from which then the insulating elements, in particular insulating panels are formed.

It is further provided that the mineral fiber web is subjected to compression in the longitudinal and / or height direction in order to achieve a higher rigidity of the insulating material elements produced therefrom. Will this compression after the application of the tensile layer, in particular of the mesh fabric, a nearly complete embedding of this mesh fabric is achieved. For this purpose, a part of the mineral fiber web can be separated and the mesh fabric between these partial webs are inserted before re-merging the part webs formed parallel to the large surfaces. After joining the partial webs, the mineral fiber web is compacted together with the mesh fabric and fixed the structure created the mineral fiber web by curing the binder.

According to a further feature of the invention it is provided that additional binder is arranged on the large surfaces of the partial webs and / or the mesh fabric

Preference is given to organic and / or inorganic binders, or mixtures of both.

An improved and in particular more intensive embedding of the fabric intended as a reinforcement in the insulating element and a good bond with the endless mineral fiber web is achieved by introducing short to very short, e.g. obtained by chopping or grinding mineral fibers prepared, in particular glass fibers in the region of the separating surfaces between the partial webs or the large surface and the adhered mesh fabric.

A development of the invention provides that the additionally introduced short mineral fibers are introduced as a fiber mass with a bulk density of 200 to 800 kg / m ³ . In order to increase the bulk density, small forces can act on the mineral fiber web for compression, which do not lead to any undesired compression of the non-tensile regions of the mineral fiber web, but lead to a bulk density of the fiber mass of 400-800 kg / m ³ .

The short fibers are bonded with about 6 to 14% by weight of binders, in particular with conventional thermosetting resins and / or resin mixtures.

In order to create insulation elements which have the requirements of non-combustibility in the sense of DIN 4102 despite the additional binder, is provided according to a further feature of the invention that as a binder inorganic binder, in particular nanoscale silica sol (Ormocere ^® ), silica sol, water glasses alone, in Combinations can be used together or in conjunction with organic binders or binder mixtures or adhesive binders.

It can also be advantageously provided that at least the tensile layers have additional water-repellent substances.

Preferably, the tensile layers described above and / or in particular the introduced reinforcing means are designed to be open to diffusion, so that a provided in the roof construction according to the invention vapor barrier air dam or on the substructure existing moisture, does not lead to an inclusion of water in the insulation. The trapped in the roof waterproofing can be quickly removed in this embodiment by the diffusion-open insulation and discharged through the roof seal to the outside air.

It is provided according to a further advantage of the invention that at least one film, preferably made of metal, a bituminous sheet and / or another, with mineral fiber laminating usual over the entire surface or part of the surface, in particular glued strip-wise on the insulating element and / or mechanically fixed, for example, sewn ,

Figur 1

einen Ausschnitt einer Dachkonstruktion mit einer Dämmung in perspektivisch dargestellter Ansicht und

Figur 2

ein Dämmelement der Dämmung gemäß Figur 1 in perspektivisch und teilweise geschnitten dargestellter Ansicht.

Further features and advantages of the invention will become apparent from the following description of the accompanying drawings, in which a preferred embodiment is shown. In the drawing show:

FIG. 1

a section of a roof construction with an insulation in perspective view and

FIG. 2

an insulating element of the insulation according to Figure 1 in perspective and partially cut shown view.

Figure 1 shows a section of a roof construction in a flat configuration. The roof construction consists of a substructure 1, on which an insulation 2 is placed. The substructure consists of trays 3, which are formed from profiled sheets, which have meandering U-shaped profiles. Each tray 3 thus consists of upper straps 4 and lower straps 5, each upper flange 4 is connected via a web 6 with a lower flange 5.

On the upper straps 4 of the trays 3 a trained as a film 7 vapor-braking air barrier is launched. In the figure 1 it can be seen that the film 7 sags slightly in the region of the lower chords 5 between adjacent webs 6.

Above the film 7, the insulation 2 is arranged, which consists of individual insulation boards 8. The insulating panels 8 have two mutually parallel and spaced large surfaces 9, two the large surfaces 9 connecting, aligned at right angles to the large surfaces 9 and parallel longitudinal sides 10 and to the long sides 10 and the large surfaces arranged at right angles narrow sides 11th on.

Here, the narrow sides 11 are aligned transversely to the production direction in a conventional, known per se continuous production of such insulation boards. The insulating panels 8 are usually made of an endless mineral fiber web and consist of stone fibers, each having a length in the micrometer range and are bound with binders.

It can be seen that the individual mineral fibers in the region of the narrow sides 11 have a flat orientation relative to the large surfaces. In contrast, the mineral fibers 12 are oriented steeply in the region of the longitudinal sides 10 of the insulating board 8 to the large surfaces 9. This orientation of mineral fibers 12 is achieved by a compression of the aforementioned continuous mineral fiber web in the longitudinal direction of the production line, ie in the direction of the surface normal of the narrow sides 11 and / or a compression in the direction of the surface normal of the large surfaces 9.

It can also be seen from FIG. 1 that the insulation board, which is shown in more detail in FIG. 2, has a layer 13 with a higher fiber density or binder density in the area of the large surface 9 which faces away from the substructure 1. In the area of the oppositely arranged large surface 9, the insulation board 8 has a tensile layer 14, which will be described below with reference to FIG 2.

The tensile layer 14 consists of a highly compressed cover layer 15, in which a mesh fabric 16 is embedded. The cover layer 15 is glued to the large surface 9 of the insulation board 8, which faces the substructure 1. On the cover layer 15, a glass fleece 17 is additionally glued as a final lamination.

The glass fleece 17 has a thread reinforcement in order to further increase its tensile strength. The cover layer 15 consists of short to very short mineral fibers, which in the form of a pulp having a bulk density of 300 kg / m ³ and a binder content of 14% by mass, wherein an inorganic binder is selected as the binder. The cover layer 15 is designed to be open to diffusion, so that diffusion of moisture contained in the roof structure through the insulation 2 is possible despite the high density.

Claims (32)

1. Roof construction in a flat and/or flat inclined form, consisting of a lower structure (1) carrying a heat and/or sound insulation (2), especially consisting of insulating boards from mineral fibre insulating materials, preferably from glass and/or rock fibres, said heat and/or sound insulation partially resting on upper chords (4) of the carrier elements (3) forming said lower structure, and an upper structure, said lower structure and/or upper structure being carrier elements that consist of individual profiled sheets (3),
   characterized in
   that said insulation (2) consists of two layers at least, of which at least one layer (14), namely at least the layer (14) that rests on the lower structure (1) is formed in a tension-resistant manner.
2. Roof construction according to claim 1,
   characterized in
   that said tension-resistant layer (14) is glued together with said at least one further layer.
3. Roof construction according to claim 1,
   characterized in
   that said tension-resistant layer (14) consists of a glass fibre mat (17), in particular reinforced by threads and/or a non-tearing fabric (16), especially a grid-like fabric made of glass, plastic and/or textile fibres.
4. Roof construction according to claim 1,
   characterized in
   that said tension-resistant layer (14) has an increased bulk density compared to that of said further layer.
5. Roof construction according to claim 1,
   characterized in
   that said further layer includes an increased binder content in the region close to the surface and facing said tension-resistant layer (14), which increased binder content serves both for a better connection of the mineral fibres there arranged and for a connection of said two layers (8; 14).
6. Roof construction according to claim 3,
   characterized in
   that said glass fibre mat (17) and/or the non-tearing fabric (16) are embedded in said tension-resistant layer (14), especially before the height and length compression of a fibre web forming said tension-resistant layer (14).
7. Roof construction according to claim 3,
   characterized in
   that said glass fibre mat (17) and/or the non-tearing fabric (16) are arranged between said tension-resistant layer (14) and said further layer.
8. Roof construction according to claim 1,
   characterized in
   that said tension-resistant layer (14) is formed as a partial length of said further layer and, after compression, is supplied to said further layer, especially under interposition of said non-tearing fabric (16) and/or said glass fibre mat (17).
9. Roof construction according to claim 1,
   characterized in
   that said tension-resistant layer (14) is glued together with said further layer by organic and/or inorganic binders.
10. Roof construction according to claim 1,
    characterized in
    that said tension-resistant layer (14) includes short to very short glass fibres especially in the region of the non-tearing fabric (16) and/or the glass fibre mat (17).
11. Roof construction according to claim 10,
    characterized in
    that said glass fibres are contained in a fibre mass with a settled apparent density of between 200 and 300 kg/m³ at an additional compression of between 400 and 800 kg/m³.
12. Roof construction according to claim 10,
    characterized in
    that said glass fibres are bound with 5 to 20 % by mass, in particular 6 to 14% by mass of duroplastic resins and/or resin mixtures and inorganic binders like especially nano-scale silica sol, silica sol, water glass or mixtures thereof with or without organic binders or binder mixtures or adhesive binders.
13. Roof construction according to claim 1,
    characterized in
    that said tension-resistant layer (14) and/or said further layer include water-repellent substances.
14. Roof construction according to claim 1,
    characterized in
    that said tension-resistant layer (14) and/or said further layer are formed diffusion open.
15. Roof construction according to claim 1,
    characterized in
    that a tension-resistant film, especially of metal, a length of bitumen or the like is glued to the said tension-resistant layer (14) and/or said further layer, over the full surface thereof or partially and especially strip-like.
16. Roof construction according to claim 1,
    characterized in
    that between the insulation (2) and the lower structure (1) a vapour sealing air barrier, especially a polyethylene film is arranged.
17. Insulating element for a roof construction in a flat and/or flat inclined form, said insulating element being in the form of an insulating board (8) made from mineral fibres, preferably glass and/or rock fibres, and comprising two mutually parallel extending major surfaces (9) that are arranged at distance to each other, two mutually parallel extending longitudinal sides (10) oriented at right angles to said major surfaces (9), and narrow sides (11) arranged at right angles to the longitudinal sides and to the major surfaces, wherein said insulating board in its condition for installation rests by a partial area thereof on upper chords of a lower structure,
    characterized in
    that said insulating board (8) consists of at least two layers (14), of which at least one layer (14), namely that layer which in its condition for installation rests on said lower structure or on any other support, is formed to be tension-resistant, and that the mineral fibres show a flat orientation relative to the major surfaces (9) in the region of the narrow sides (11) and a steep orientation relative to the major surfaces (9) in the region of the longitudinal sides (10).
18. Insulating element according to claim 17,
    characterized in
    that said tension-resistant layer (14) is glued to said at least one further layer.
19. Insulating element according to claim 17,
    characterized in
    that said tension-resistant layer (14) consists of a glass fibre mat (17), in particular reinforced by threads and/or a non-tearing fabric (16), especially a grid-like fabric made of glass, plastic and/or textile fibres.
20. Insulating element according to claim 17,
    characterized in
    that said tension-resistant layer (14) has an increased bulk density compared to that of said further layer.
21. Insulating element according to claim 17,
    characterized in
    that said further layer includes an increased binder content in the region close to the surface and facing said tension-resistant layer (14), which increased binder content serves both for a better connection of the mineral fibres there arranged and for a connection of said two layers (14).
22. Insulating element according to claim 19,
    characterized in
    that said glass fibre mat (17) and/or the non-tearing fabric (16) are embedded in said tension-resistant layer (14), especially before the height and length compression of a fibre web forming said tension-resistant layer (14).
23. Insulating element according to claim 19,
    characterized in
    that said glass fibre mat (17) and/or the non-tearing fabric (16) are arranged between said tension-resistant layer (14) and said further layer.
24. Insulating element according to claim 17,
    characterized in
    that said tension-resistant layer (14) is formed as a partial length of said further layer and, after compression, is supplied to said further layer, especially under the interposition of said non-tearing fabric (16) and/or said glass fibre mat (17).
25. Insulating element according to claim 17,
    characterized in
    that said tension-resistant layer (14) is glued together with said further layer by organic and/or inorganic binders.
26. Insulating element according to claim 17,
    characterized in
    that said tension-resistant layer (14) includes short to very short glass fibres especially in the region of the non-tearing fabric (16) and/or the glass fibre mat (17).
27. Insulating element according to claim 26,
    characterized in
    that said glass fibres are contained in a fibre mass with a settled apparent density of between 200 and 300 kg/m³ at an additional compression of between 400 and 800 kg/m³.
28. Insulating element according to claim 26,
    characterized in
    that said glass fibres are bound with 5 to 20 % by mass, in particular 6 to 14% by mass of duroplastic resins and/or resin mixtures and inorganic binders like especially nano-scale silica sol, silica sol, water glass or mixtures thereof with or without organic binders or binder mixtures or adhesive binders.
29. Insulating element according to claim 17,
    characterized in
    that said tension-resistant layer (14) and/or said further layer include water-repellent substances.
30. Insulating element according to claim 17,
    characterized in
    that said tension-resistant layer (14) and/or said further layer are formed diffusion open.
31. Insulating element according to claim 17,
    characterized in
    that a tension-resistant film, especially of metal, a length of bitumen or the like is glued to the said tension-resistant layer (14) and/or said further layer, over the full surface thereof or partially and especially strip-like.
32. Insulating element according to claim 17,
    characterized in
    that between the insulation (2) and the lower structure (1) a vapour sealing air barrier, especially a polyethylene film is arranged.

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