WO1998028501A1

WO1998028501A1 - An insulating element for clamping installation between roof rafters or beams of other wooden constructions

Info

Publication number: WO1998028501A1
Application number: PCT/EP1997/007234
Authority: WO
Inventors: Joachim Schlögl; Karl-Hans Bugert
Original assignee: Isover Saint-Gobain
Priority date: 1996-12-23
Filing date: 1997-12-22
Publication date: 1998-07-02
Also published as: AU5762998A; DE69711365T2; NO983870L; CZ300498A3; TR199801257T1; PL208971B1; CZ295020B6; NO983870D0; HU224187B1; JP2000505851A; ES2172037T3; EP0886704B1; ATE215158T1; PL328825A1; KR100442955B1; EP0886704B2; EP0886704A1; DK0886704T3; CA2246716A1; JP3819039B2

Abstract

The invention relates to an insulating element (1) for clamping installation between limiting surfaces, in particular between rafters (4) of roofs such as steep roofs, or between beams or the like, in particular of wooden frame constructions for outside or inside walls of buildings or wooden beam ceilings and the like, in particular made of mineral wool in the form of an insulating panel or insulating sheet wrappable into a roll or insulating panels obtained by cutting the insulating sheet, the panel/sheet having a plurality of insulating layers (2, 3) extending perpendicular to the thickness of the insulating element, at least one of which is designed as a clamping-type holding element (3) over the remaining insulating layers for clamping installation of the panel/sheet such that said holding element (3) exerts a greater pressure on the limiting surfaces in the installed state than the remaining insulating layers due to its higher elastic force, transmitted to said surfaces through its side surfaces.

Description

An insulating element for clamping installation between roof rafters or beams of other wooden constructions

This invention relates to an insulating element according to the preamble of claim 1.

Such insulating elements (or insulating material elements) are known and used in particular for clamping installation of sheets, or singled insulating panels cut off the sheet, between roof rafters, balcony or other limiting surfaces. This is a market with production figures that have been rising for decades, the insulating sheet being installed on the spot by experts from the building trade, but also very often by untrained personnel, i.e. do-it-yourselfers. In particular since it has become common on the market to insulate steep roofs with mineral wool, such insulating sheets, also referred to as clamping felts, have been able to increase their market share constantly.

In the production and stock keeping of an insulating element the manufacturer must take into account quite generally that the clear widths between the rafters of roofs or beams of other wooden constructions and the heights thereof, i.e. latticework depths, can differ to a considerable degree. For these reasons e.g. so-called shoulder mats for adapting to different widths between the rafters or beams are produced and kept in stock in finely graded widths, for example in width gradations of 100 mm. Further, clamping felt thicknesses of about 80 mm to 220 mm and more are offered today. This of course involves enormous stock keeping in production, sale and distribution, but also on the building site.

Another special problem with such products is the necessary expenditure of material, which should always be reduced for reasons of cost, but which is especially important because large surfaces must be covered with insulating material in the preferred cases of application such as steep roof insulation. Further, the considerable material costs are not least due to the fact that mineral wool is increasingly produced from biodegradable compositions or must be produced according to specific national regulations, which can lead to much higher prices. The problem of the invention is to provide an insulating sheet or insulating panel for clamping installation between roof rafters, beams or other limiting surfaces which permits the expenditure of material to be reduced with no loss of necessary insulating properties, i.e. an optimization of the product to the use of material necessary for fulfilling the technical service value, in particular the thermal insulating ability.

According to a further aspect, insulating elements for clamping installation between roof rafters or beams of wooden frame constructions are to be provided not only with a saving of material over conventional insulating elements and nevertheless an optimal clamping effect, but also storage, transport and packaging advantages through a reduction of the package volume in view of the fact that such insulating elements are marketed within a foil package.

A further aspect of the invention is to provide an insulating sheet or insulating panels in a thickness range which ensures full insulation as an insulating element with a certain thickness at different and varying beam thicknesses (latticework depths) and in particular permits continuous compensation of different thicknesses. The insulating sheet should nevertheless be easy to produce, and the installation of the insulating sheet or of insulating panels by mere clamping in no way impaired.

This problem is solved according to the invention by the features contained in the characterizing part of claim 1, whereby expedient, in particular advantageous embodiments are characterized by the features contained in the sub- claims.

The invention is characterized mainly in that the insulating sheet or panel has a special clamping-type holding element, also referred to in the following as a clamping layer. This allows a very considerable reduction of material in the total insulating layer since only the clamping-type portion of the panel or sheet necessary for clamping installation need be designed in view of its clamping function property in order to ensure a perfect and lasting hold of the material. The rest or the remaining layers of the panel or sheet can be adjusted suitably with no reference to the clamping and holding function, for example with lower elastic force than the clamping layer, in particular with lower bulk density, and need be de- signed solely for the requirement of thermal insulation. By e.g. grading the bulk density within the panel or sheet one obtains an accordingly great saving of material in particular with consideration of the fact that considerable surfaces must be insulated in the intended cases of application of steep roof insulation. In the present case the properties of the clamping layer are obtained by a higher bulk density over the remaining layer. Higher bulk density is used here to attain the clamping function of the clamping-type holding element. The bulk density in the remaining area of the insulating sheet or panel can be selected according to the particular requirement profile, in particular with respect to thermal conductivity. The clamping layer of course also fulfills the requirement for thermal insulation.

In a particularly preferred embodiment the panel or sheet is divided into two layers, one of which forms the clamping layer and has a higher elastic force, in particular due to a higher bulk density, than the remaining layer which performs only the fUling function or insulating function. The properties, such as elastic force of the clamping-type holding element, can be achieved not only by increased bulk density but also by suitable adjustment of binder content and/or fiber quality and/or fiber orientation.

The multipartition, in particular bipartition, of the insulating element into at least two portions with different natures achieves a reduction of material according to the invention while retaining or optimizing the clamping effect over conventional mineral wool insulating materials, whereby at least one portion acts in clamping fashion. In this connection a certain sag occurs in the installed state e.g. between roof rafters by reason of the dead weight of the insulating element, so that the clamping layer preferably located above in this case exerts a clamping- inducing effect on the remaining insulating layer below. Since the bulk density of the remaining insulating layer serving as a filling layer can be minimized according to the invention, one obtains not only a saving of material but also considerable packaging advantages, since the product can then be compressed better. This is of special advantage for insulating elements supplied in roll form since it permits the package volume to be considerably reduced, resulting in reduced transport and storage volumes. Alongside the particularly preferred double-layer embodiment of the insulating sheet or insulating panel it is also possible to provide two filling layers or two clamping layers in the case of only one filling layer, etc. The number and arrangement of filling layers and clamping layers can be selected accordingly by the expert.

As mentioned above, the property of the clamping layer can also be adjusted, rather than via bulk density, through fiber geometry, fiber position, fiber forming, fiber orientation, binder content or other additives strengthening the clamping layer. It is essential that the clamping layer has a sufficient spreading or elastic force to ensure the necessary frictional forces between clamping layer and limiting surfaces. It generally holds that the clamping layer is stiff enough so that the insulating element can be clamped between the rafters with sufficient pressure and has a press fit there, whereas the filling layer can be soft and compressible enough to permit a thickness compensation function at different latticework depths. When elastic force is adjusted via bulk density, it is expedient for the ratio of clamping layer bulk density to filling layer bulk density to be > 1, preferably > 1.5.

In the following, preferred embodiments of the invention will be described with reference to the schematic drawing, in which:

Figure 1 shows a perspective partial view of an inventive insulating element,

Figure 2 shows a sectional view illustrating the installation conditions of an insulating sheet or insulating panel within a square of a steep roof,

Figure 3 shows a sectional view through an insulating sheet or insulating panel in the state at the beginning of installation between beams or posts of a vertical wooden frame construction for a building wall or the like, if the thickness of the insulating element is to be adjusted to a latticework depth smaller than the thickness of the insulating element,

Figure 4 shows a view like Figure 3 but in the installed position of the insulating sheet or insulating panel, Figure 5 shows an insulating sheet wrapped into a roll, partly in a stretched state to show the singling of insulating panels from this insulating sheet for clamping installation between rafters,

Figure 6 shows a diagram to illustrate the saving potential when using the inventive insulating element.

The insulating element in the form of insulating sheet or insulating panel 1 shown in a perspective partial view in Figure 1 is constructed from two layers, namely filling layer 2 designated FS and clamping layer 3 designated KS. The two layers have different natures and thus also different properties. In a preferred case of application, namely for clamping installation of insulating sheet or insulating panel 1 between rafters of a roof construction or between posts of a wooden frame construction, the layers produced from mineral wool with suitable binders are designed with different bulk densities. Clamping layer 3 is designed in its density with a view to clamping installation of the sheet or panel and has in particular a greater bulk density than filling layer 2. The latter can be designed independently of clamping function and therefore have reduced bulk density, its density being selected solely with a view to the desired insulating properties.

Figure 2 shows insulating sheet 1 cut off a sheet rolled into the insulating material roll according to Figure 5 in the installed position between two adjacent rafters 4 of a steep roof construction, reference sign 5 designating waterproof sheeting customarily used in roof works and disposed on the upper side of rafters 4. In the shown embodiment of Figure 2, clamping layer 3 is disposed above, i.e. on the roof side, and thus adjacent waterproof sheeting 5, whereas filling layer 2 is disposed toward the room, i.e. below. Insulating sheet 1 shown in Figure 2 is adjusted in terms of thickness to thickness d3 of the rafters, but this is not necessarily the case. The layer thicknesses of clamping layer 3 and filling layer 2 are stated as dl and d2. For installation, insulating sheet 1 is cut off a roll according to Figure 5 with an overmeasure over clear width D between adjacent rafters 4, the overmeasure being such that insulating sheet 1 is inserted in clamping fashion between adjacent rafters and then held by the clamping effect. A useful overmeasure for conventional squares is about 1 cm. Both layers 2 and 3 are formed from mineral wool, as stated above, but they differ with respect to their mechanical properties. These different properties are achieved in the embodiment of Figure 2 by different bulk densities of layers 2 and 3. Filling layer 2 has a bulk density lower than the bulk density of clamping layer 3. Clamping layer 3 with its greater bulk density has a higher elastic force between the limiting surfaces than filling layer 2, the elastic force being such that the insulating panel can be disposed firmly with a press fit when incorporated between adjacent rafters so that no special fastening means are necessary. Suitable bulk densities for the clamping layer are > 10 kg/m³, a preferred range of application for clamping installation between rafters or posts of a wooden frame construction being a density value in the range of 10 kg/m³ to 30 kg/m³. An especially preferred range for bulk density is from 15 kg/m³ to 25 kg/m³ and especially preferred bulk densities for the clamping layer are for instance in the range of 17 to 19 kg/m³.

It is essential for the bulk density adjustment of clamping layer 3 in the case of application for roof insulation, in particular for insulating horizontal wooden latticework constructions, such as so-called frames between opposing rafters and squares at a roof slope of < 60°, that clamping layer 3 is sufficiently strong and stiff but nevertheless flexible without buckling under the dead weight of insulating element 1 consisting of layers 2 and 3. In the installed position of Figure 2 the insulating sheet can sag slightly under its dead weight, this weight- induced slight sag or downward bulge resulting in a spread of the insulating sheet clamped between rafters 4 especially in the lower area of filling layer 2, thereby building up spreading forces. The clamping fixation of the insulating sheet between rafters 4 is effected mainly by the restoring and frictional forces built up because of clamping layer 3, which are additionally supported by the spreading forces within filling layer 2 induced by clamping layer 3, whereby the frictional forces of filling layer 2 over rafters 4 of course also contribute to the clamping effect. Clamping is therefore effected in the embodiment of Figure 2 both by actual clamping layer 3, whose strength is designed for the purpose of the clamping function, and by filling layer 2 via the spreading forces induced there because of sag by reason of the dead weight of the insulating sheet. A reverse arrangement of insulating sheet 1 between the limiting surfaces of roof rafters or beams of vertical wooden frame constructions is of course also possible, whereby filling layer 2 is located adjacent waterproof sheeting 5 in the roof area and the clamping layer facing the room. However, with vertical wooden frame constructions, filling layer 2, with the outside surface of clamping layer 3 flush with the outside surface of beams 4, fills the remaining space up to wall panel 5, e.g. derived timber panel, and can thereby act as a compensation layer. That is, because of the good compressibility of filling layer 2 designed with low bulk density, different beam thicknesses d3 can be bridged with one and the same insulating element. For example it is conceivable to bridge different thicknesses in the range of 140 mm to 220 mm continuously with insulating panel 1 with a thickness of 220 mm by filling layer 2 being compressed to a greater or lesser degree and thus performing a compensation function when the insulating panel is incorporated. The aforementioned value of 220 mm for total thickness dl and d2 of insulating sheet 1 is of course an exemplary value, because the thickness of the product can also be adjusted to other latticework depths. It is further possible to use two products of different thicknesses with uniform gradation or else three products of different thicknesses with uniform gradation, if required. This is ultimately dependent on market behavior, in particular on the expected differences of rafter or beam thicknesses as are used in the individual constructions. This can vary from country to country, possibly with corresponding consideration of building regulations.

Figures 3 and 4 show installation conditions for an insulating panel or insulating sheet between a vertical wooden frame construction with posts or beams 4, as are used for example for building walls, in particular industrially prefabricated room cell modules. Merely by way of example the outer side is illustrated here by the wall panel of derived timber product or paneled wall 5'. Figure 3 shows the beginning of the installation process, the filling layer formed as compensation layer 2' being located in the space between the two beams 4'. Clamping layer 3 is then pressed between beams 4' with application of force P so that the outside surface of clamping layer 3 extends flush with the outside surface or outside edge of beams 4', as Figure 4 shows. When clamping layer 3 is pressed in, compensation layer 2' is accordingly compressed and thus also performs a compensation function along with the insulating function, since different beam thicknesses can be bridged with one and the same product, i.e. with an insulating element of equal thickness. In this case of application clamping layer 3 is again designed with higher strength over compensation layer 2', in particular with higher bulk density, the aforementioned ranges being applicable here too. The bulk density in both cases of application for the filling layer is < 30 kg/m³, in particular < 15 kg/m³ and preferably < 10 kg/m³, the two bulk densities being coordinated with each other such that the ratio of clamping layer bulk density to filling layer bulk density is > 1.

Particular thickness dl of clamping layer 3 is minimized in all cases of application to the technically necessary thickness required for fixing the insulating layer between the corresponding limiting surfaces of roof rafters or beams of wooden latticework constructions. The particular values for the thicknesses also depend on the design of the wooden frame construction and in particular on the width to be bridged between adjacent rafters or beams. With respect to filling layer 2 it is quite generally advantageous for it to more compressible than clamping layer 2, which permits the above-described compensation function, on the one hand, but in particular also provides advantages in packaging, on the other hand. One can thus achieve an insulating roll with reduced diameter but equal length of the insulating sheet, which reduces the package volume and thus provides considerable transport and storage advantages. The insulating sheet in the form of a roll is compressible to ranges of 1 : 2.5 to 1 : 4.5. With such an insulating sheet or insulating panel cut thereoff one can also obtain a classification in thermal conductivity group 040 according to DIN 18165, the filling layer falling within thermal conductivity group 045 by reason of its bulk density and the clamping layer within thermal conductivity group 035 by reason of its bulk density, while in the middle the insulating panel or insulating sheet fulfills the criteria of thermal conductivity group 040 according to DIN 18165. By suitably selecting the bulk densities (RD), it being well known that (lambda) λ = f (RD), one can also obtain a total thermal conductivity group of 035. Figure 5 shows an especially preferred embodiment, namely an insulating sheet wrapped into a roll for clamping installation between the limiting surfaces of rafters or beams, in particular rafters of a steep roof. Insulating sheet 6 is shown partly in the stretched state. Number 2 again designates the filling layer with a compensation function and number 3 the clamping layer, which is disposed here on the outside in the rolled position of the insulating roll. The clamping layer can also be disposed on the inside in the rolled position, which depends on the case of application in accordance with the statements according to Figure 2, i.e. the actual installation conditions. On surface 7 of the layer located on the inside in the rolled position, that is the filling layer in the described embodiment here, there are marking lines 8 extending perpendicular to lateral edges 9 of insulating sheet 6. In the example, marking lines 8 are applied at equal distances, distance d between two adjacent marking lines preferably being 100 mm. As Figure 5 illustrates, marking lines 8 need not be executed as continuous lines but can also be broken lines. Marking lines 8 are expediently not formed by cuts or the like but are merely optically effective without influencing the handling and effectiveness of the material of mineral wool sheet 6. To fill a square with a given width of for example 700 mm, one measures longitudinal portion L with a length of 710 mm starting out from leading edge 10 of insulating sheet 6 along marking lines 8 with consideration of the overmeasure of for example 1 cm necessary for press fit and cuts it off at 11. For this purpose one sets knife 12 at the measured cutting line in the way indicated in Figure 5 and draws it through the material in the direction of arrow 13 parallel to adjacent marking line 8.

Insulating panel 14 thereby singled is rotated for installation so that previously lateral edges 9 of insulating sheet 6 come to be above and below and longitudinal portion L thus determines the width of mineral wool panel 14. In this position mineral wool panel 14 is inserted into the square between two adjacent rafters 4. Overmeasure U of longitudinal portion L over width D of the square at the place of installation of 10 mm or a little more in the example results in the desired press fit of mineral wool panel 14. After insertion between rafters 4 mineral wool panel 14 therefore has a press fit between the rafters through the clamping effect. Thus formed insulating sheet 6 can be used with uniform width for laying in squares with different width D between adjacent rafters if panel 14 is cut off the insulating sheet in accordance with width D between the rafters. Because of the simultaneous possibihty of compensation one can therefore use the insulating sheet shown in Fig. 5 with a uniform width dimension of the insulating sheet and uniform thickness of the insulating sheet for squares or bays with differing width D and differing rafter and beam thicknesses d3. This results in a considerable saving of assortment, because insulating sheet 6 need no longer be kept in finely graded thicknesses but one insulating sheet of uniform width and thickness can cover a variety of roof and wooden frame constructions with different width between the rafters or beams and with different latticework depths.

Fig. 6 shows the saving potential for insulating material in percentages over conventional insulating sheets available on the market. One thus obtains considerable savings in the range of 10 to 23% over the thicknesses of insulating sheets or panels customarily used in particular for insulating roofs, which leads to a considerable saving of material in view of the quantities of insulating sheet used per year for these purposes.

Table 1 shows by way of example variants of layer combinations with different thicknesses, bulk densities and weights per unit area of the individual partial layers.

This table indicates that all variants according to the invention have lower weights per unit area than the standard version and thus lead to a noticeable saving of material. One can further see that layer thickness, bulk density and weights per unit area of the partial layers can thereby be varied.

If e.g. the filling layer is adjusted so that its thickness can be compressed during installation depending on the rafter height or wooden latticework depth, one can not only save material, albeit to a smaller extent, but also optimize the assortment. One thus sees in Table 1 that if e.g. a sheet/panel of variant 3 with a thickness of 220 mm and with a weight per unit area of 2.82 kg/m² is compressed to a beam thickness of 180 mm, one can even obtain a saving of material of 0.06 kg/m² over a sheet/panel of the standard version with a thickness of 180 mm and a weight per unit area of 2.88 kg/m². The advantage in this example lies mainly in the optimized assortment. A clearer saving of material is given e.g. with beam thickness d3 of 200 mm, however, since here the weight per unit area of the standard version of 3.00 kg/m² is considerably higher compared to variant 3 again with 220 mm thickness and a weight per unit area of 2.82 kg/m². The saving of material is therefore 0.18 kg/m³ in this example.

Table 1

Comparison of weights per unit area in kg/m² of insulating sheets/panels in various combinations of layers with different bulk densities

BH = Height of limiting surface or wooden latticework depth (mm) d = Thickness KS = Clamping layer (3) djjs ⁼ Thickness of clamping layer FS = Filling layer (2) dps = Thickness of filling layer Rrj = Bulk density (kg/m³)

Claims

1. An insulating element for clamping installation between limiting surfaces, in particular between rafters (4) of roofs such as steep roofs, or between beams (4') or the Hke, in particular of wooden frame constructions for outside or inside walls of buildings or wooden beam ceilings and the like, in particular made of mineral wool in the form of an insulating panel or insulating sheet (6) wrap- pable into a roll or insulating panels (1) obtained by cutting the insulating sheet, characterized in that the panel/sheet (1, 6) has a plurality of insulating layers extending perpendicular to the thickness of the insulating element, at least one of which is designed as a clamping-type holding element over the remaining insulating layers for clamping installation of the panel/sheet such that said holding element exerts a greater pressure on the limiting surfaces in the installed state than the remaining insulating layers due to its higher elastic force, transmitted to said surfaces through its side surfaces.

2. The insulating element of claim 1, characterized in that the elastic force of the clamping-type holding element formed as a clamping layer (3) is obtained by suitably fixing the bulk density and/or binder content and/or fiber quality and/or fiber orientation and/or other suitable strengthening means.

3. The insulating element of claim 1 or 2, characterized in that the clamping-type holding element limits an outside surface of the panel/sheet (1, 6) or is disposed within the panel/sheet.

4. The insulating element of any of the above claims, characterized in that the clamping layer (3) is aligned in its thickness substantially with the clamping function technically necessary for fixation between the limiting surfaces.

5. The insulating element of any of the above claims, characterized in that the panel/sheet (1, 6) is formed in at least two layers from the clamping layer (3) and a remaining insulating layer as a filling layer (2).

6. The insulating element of any of the above claims, characterized in that the thickness of the clamping layer (3) is < 50% of the total thickness of the panel/sheet (1, 6) comprising the clamping and filling layers (2, 3) before instal- lation, being preferably in the range of 20 to 50%, in particular 20 to 40% and particularly preferably 30 to 40%.

7. The insulating element for clamping installation between nonvertical limiting surfaces, in particular between rafters (4) of steep roofs or between beams of other wooden constructions, such as wooden beam ceilings and the like, in particular according to at least one of claims 1 to 6, characterized in that the clamping-type holding element (clamping layer (3)) is disposed facing away from the room in the installed position of the panel/sheet (1, 6) e.g. between roof rafters (4).

8. The insulating element for clamping installation between vertical limiting surfaces, in particular between beams (4') of wooden frame constructions for outside or inside walls of buildings and the hke, according to claims 5 and 6, characterized in that the fining layer is formed as a compensation layer (2') for adaptation to different beam heights (latticework depths).

9. The insulating element of claim 8, characterized in that the compensation layer (2') is formed as a flexible compressing zone.

10. The insulating element of any of the above claims, characterized in that the clamping layer (3) has a bulk density > 10 kg/m³, being preferably in the range of 10 to 30 kg/m³, in particular in the range of 15 to 25 kg/m³.

11. The insulating element of any of the above claims, characterized in that the filling or compensation layer (2; 2') has a bulk density of < 30 kg/m³, in particular preferably < 15 kg/m³.