EP0203987A1

EP0203987A1 - Means of attachment for covering plates on buildings, particularly roofing sheets

Info

Publication number: EP0203987A1
Application number: EP19860900312
Authority: EP
Inventors: Leif Eriksson; Lars Gidlund
Original assignee: Granges Aluminium AB
Current assignee: Granges Aluminium AB
Priority date: 1984-12-04
Filing date: 1985-12-02
Publication date: 1986-12-10
Also published as: DE3590635T1; GB8618431D0; GB2178774A; SE8406137L; WO1986003537A1; SE8406137D0; SE445657B; GB2178774B

Abstract

Moyen comprenant une traverse de fixation allongée (12) conçue pour constituer une surface de fixation des plaques de couverture (11), et au moins deux fers de fixation (15) de la traverse sur l'immeuble. Ces fers de fixation (15) s'étendent sur au moins une partie de la traverse (12) qu'ils maintiennent de sorte que celle-ci puisse être déplacée le long de la surface de l'immeuble perpendiculairement à son sens longitudinal, de manière à absorber les mouvements thermiques des tôles. Les fers de fixation (15) peuvent être constitués de pièces métalliques recourbées couvrant la largeur de la traverse, laquelle est pourvue de surfaces glissantes conçues pour s'appuyer contre une surface glissante (20).Means comprising an elongated fixing crosspiece (12) designed to constitute a surface for fixing the cover plates (11), and at least two fixing irons (15) of the crosspiece on the building. These fixing irons (15) extend over at least part of the crosspiece (12) which they hold so that it can be moved along the surface of the building perpendicular to its longitudinal direction, from so as to absorb the thermal movements of the sheets. The fixing irons (15) may consist of curved metal parts covering the width of the cross-member, which is provided with sliding surfaces designed to bear against a sliding surface (20).

Description

Means of attachment for covering plates on buildings, particularly roofing sheets

Technical Field

The present invention relates to a means of attachment for covering plates on buildings, particularly roofing sheets, comprising an elongated mounting crossbar, which is intended to form a mounting surface for the covering pla¬ tes, and at least two clamps, which are attached to the building and adapted to secure the mounting crossbar. The means of attachment is primarily intended for roofing sheets but can also be used for fastening other plates, for example facade panels. Background Art

It is previously known to use resilient fastening means for attaching roofing sheets. Such fastening means may be bolts or screws which are inserted through holes in the roofing sheets and the tips of which are adapted to be fastened to a sub-roof or a girder in such a way that the fastening means can be tilted within an angle range. This will give the attached roofing sheets a degree of freedom, for example for thermal movements. However, these fastening means have to be rather long in order to give the roofing sheets a sufficient ability of movement, and this is often a disadvantage. Furthermore, it is difficult to provide a satisfactory sealing between the heads of the movable fas¬ tening means and the roofing sheets. If fastening means having little or no flexibility are used, the attachment of the sheets will become comparatively rigid, so that the sheets obtain a low ability of taking up thermal stress. Therefore, only comparatively short sheets can be used which makes the construction work more difficult and more expensive.

Disclosure of Invention

The main object of the invention is to provide a means of attachment for covering plates on buildings, particular- ly roofing sheets, which will give the attached plates a high freedom of motion, so that very long plates can be used, and does not cause difficult leakage and sealing problems. A further object is to provide a means of attach- ment having a low height, so that the covering plates can be applied very close to an existing roof. Theese objects are achieved according to the invention by giving the means of attachment the features set forth in the claims. Due to the fact that the clamps of the means of attachment are adapted to extend over at least a portion of the mounting crossbar and to hold the crossbar in such a way that the crossbar can be moved along the surface of the building perpendicularly to its longitudinal direction, the covering plates can be attached to the cross bar by means of usual, rigid screw means which are cheap to manufacture and easy to apply and, furthermore, which are easy to seal against the plates, because they can be drawn tight and not are subject to any movements. Due to the fact that the clamps may consist of-strip-shaped elements running across the crossbar, which can be provided with a low height,the covering plates can be applied very close to the existing building surface to be covered. This is a great advantage, particularly when roofing sheets are applied, because the roofing sheets then are exposed to smaller wind forces and the underlying roof surface can provide a counter pressure on the plate, so that a heavy spot load on the sheet, for example when a person steps on the plate, is distributed over a large area. Thus, the roofing sheets do not have to be made self-supporting. By providing the mounting crossbar with sliding surfaces and positioning a slide plate at least in some positions between the existing roof surface and the mounting crossbar, the crossbar can be made very easy to move. Brief Description of Drawings The means of attachment according to the invention will now be further described below with reference to the accompanying drawings. Fig. 1 is a perspective view showing the mounting of a roofing sheet on an existing roof surface by means of one embodiment of the means of attachment according to the in¬ vention. Fig. 2 is a cross section through the means of attach¬ ment according to Fig. 1 along the line II-II.

Fig. 3 is a cross section through a modified embodi¬ ment of the invention. Best Mode for Carrying Out the Invention Fig. 1 shows a portion of a roof surface 10 that is to be covered with shaped roofing sheets 11, of which only one is shown on the drawing. A mounting crossbar 12 is provided on the existing roof surface 10 and runs along the whole length of the pitch. Thus, the crossbar runs in parallel with the ridge of the house. The roofing sheet 11 is attached to the crossbar 12 by means of screws 13,14 in such a way that the crossbar runs perpendicularly to the direction of the ridges of the sheet. The crossbar is secu¬ red by means of clamps 15, of which only one is shown. The ends 16,17 of the clamps 15 are attached to the roof on either side of the crossbar 12 by means of screws 18,19. The clamps are adapted to extend over the whole crossbar perpendicularly to the longitudinal direction of the cross¬ bar and are so shaped that the cross bar can be moved along the roof surface perpendicularly to its longitudinal direc¬ tion. A slide plate 20 is provided on the roof surface 10 under the crossbar to facilitate the moving of the cross¬ bar. The slide plate extends under the whole length of the crossbar 12 and has a width that is slightly larger than the distance between the attaching screws 18,19, so that it can be attached to the roof surface by means of these screws.

The crossbar 12 consists of an elongated sheet, the longitudinal edges 21,22 of which are bent downwards and slightly rounded, so that the central portion of the sheet forms a ridge 23 which runs in the longitudinal direction of the sheet and which has a substantially plane top side, as shown in Fig.2. The plane top side of the ridge 23 forms a fastening surface for the sheets 11. The attaching screws 13,14 of the sheets can be screwed into the fastening sur¬ face, as shown in Fig. 2, and sealed by means of gaskets or sealing rings, if necessary. The rounded edges 21,22 of the sheet are adapted to form sliding surfaces for the sheet 12, so that the sheet easily can slide on the slide plate 20.

The clamp 15 consists of an elongated, comparatively narrow sheet strip, the ends 16,17 of which are bent down¬ wards and bent again to form bearing surfaces for the attaching screws 18,19, so that the central portion 24 of the strip forms a bridge-shaped portion running across the crossbar 12 and extending on both sides of the crossbar, as clearly shown in Fig. 2. The clamp 15 has an inside height HI which is as high as or slightly higher than the outside height H2 of the crossbar 12, so that the crossbar can be moved between the downwards bent ends 16,17 of the strip in the space 25 formed between the central portion 24 of the strip and the slide plate 20. The ends 16,17 of the strip are bent in such a way that they run obliquely from the central portion 24 of the strip to give the strip the best possible stability.

The slide plate 20 can preferably be a thin plate of plastics or any other material having a low surface fric¬ tion coefficient.

Fig. 3 shows a modified embodiment of the means of attachment in which the mounting crossbar 32 is provided with plane ends 26A,26B as sliding surfaces and the clamp 27 consists of a flexible metal strip. The strip is attach¬ ed by means of long screws 28,29 extending through an upper layer 30 of the roof surface. A slide plate 31 is provided on the roof surface under the crossbar 32 and attached by means of the screws 28,29 passing through the slide plate 31. The slide plate may consist of a strip of stainless steel having a thickness of 2-3 millimetres. This strip will then form a spacing element between the screws 28,29, so that the screws cannot be moved in relation to each other. The roofing sheets 11, not shown in Fig. 3, are attached to the crossbar by means of screws in the same way as shown in Figs. 1 and 2. Also in this case the crossbar can be moved between the attaching screws of the clamp during longitudinal movements of the roofing sheets. How¬ ever, the clamp abuts against the crossbar with a certain pressure and thus provides a better attachment of the crossbar. When the crossbar is moved, the shape of the clamp is slightly changed, i. e. the top of the clamp is moved towards one or the other of the attaching screws. In case the roof surface consists of a brittle or soft mate¬ rial, it is important that the slide plate forms a spacing element between the screw heads, so that the heads cannot be pulled towards each other, when the crossbar is moved, because in such a case the roof surface may be damaged, so that the screws are loosened.

Shaped sheets can be manufactured in long lengths, i. e. having a long length in the direction of the ridges. Sheets of 10-20 metres in length can be manufactured and handled. In sheets of these lengths the thermal movements at the sheet ends may be considerable. However, due to the fact that the crossbar is positioned perpendicularly to the direction of the ridges of the sheets, sheets of maximum length can be used, because the crossbar easily can be pro¬ vided with the necessary mobility under the clamps 15,27, as shown in Figs. 2 and 3, to take up the appearing thermal movements. Due to the fact that the crossbar is provided with sliding surfaces and these sliding surfaces rest upon a slide plate, the frictional resistance during the move¬ ment of the crossbar is negligible, which contributes to the reduction of the thermal stress in the sheets.

By manufacturing the clamps of thin sheet strips or metal straps and giving the crossbar a minimum height, the roofing sheets can be applied very close to the existing roof surface. This will reduce the load on the sheets from a blowing wind. Furthermore, spot loads on the sheets can be distributed over a large area, so that there is no need to make the sheets self-supporting. Therefore, the sheets can be made thinner and the attaching means can be fewer and/or weaker. This will reduce the material costs and simplify the mounting work, which implies a substantial reduction of costs.

While only one embodiment of the means of attachment according to the invention has been shown and described above, it is evident that many variations and modifications are possible within the scope of invention. For example, it is not necessary that the clamps extend across the whole crossbar, as the clamps can be designed with a projecting arm whih extends over only a portion of the width of the crossbar and which forms a pocket into which the crossbar can run in part. Such an attachment may be sufficient, when the sheets in any place are rigidly connected to the buil¬ ding surface to be covered with the sheets. Furthermore, the clamps m.i,, consist of straight strips or bars spaced from the slide surface by means of spacing means and may be attached on only one side of the crossbar by means of one or more screws. The crossbar may have a different cross section shape, for example with inwardly bent edges, and does not have to form a plane mounting surface. The sliding surfaces of the crossbar may consist of a number of separa- te, semi-spherical projections which for example have been stamped into the sheet, and not of longitudinal edges or rims. Alternatively, the crossbar may consist of an extru¬ ded section of aluminium. The crossbar can also be substan¬ tially thicker and consist of, for example, insulating material which has a sufficient inherent flexibility or which has been provided with a sliding surface, if the sur¬ face of the building is to be provided with additional insulation. In this case, the clamps can also pass through holes or extend into cavities in the crossbars. The slide surface may consist of a continuous plate or of a number of separate, spaced plates or strips which not necessarily have to be positioned under the clamps.

Claims

1. Means of attachment for covering plates on buildings, particularly roofing sheets, comprising an elongated moun¬ ting crossbar (12;32), which is intended to form a mounting surface for the covering plates (11), and at least two clamps (15; 27), which are attached to the building and adapted to secure the mounting crossbar, charcaterized in that the clamps (15; 27) are designed with a projecting arm extending over at lest a portion of the crossbar (12; 32) and having an inside height (HI) which is as high as or slightly higher than the outside height (H2) of the cross¬ bar (12;32) in such a way that the crossbar can be moved along the surface of the building (10) perpendicularly to its longitudinal direction in the space (25) formed between each clamp arm and the surface of the building.

2. Means of attachment according to claim 1, characterized in that each clamp consists of a hold (15; 27), the ends of which are attached to the building on either side of the crossbar (12;32), the distance between the attaching points of the hold (18, 19; 28, 29) being larger than the width of the crossbar (12;32).

3. Means of attachment according to claim 2, characterized in that the hold consists of a strip-shaped element (15), the central portion (24) of which is bent outwards along a distance longer than the width of the crossbar (12).

4. Means of attachment according to claim 2, characterized in that the hold consists of a flexible strap (27) which has a curved shape and is adapted to abut against the crossbar (32) .

5. Means of attchment according to any one of the prece- ding claims, characterized in that a slide surface (20;31) is provided on the surface (10) of the building and that the crossbar (12;32) abuts against this slide surface.

6. Means of attachment according to claim 5, characterized in that the slide surface consists of at least one slide plate (20; 31) running under at least a portion of the crossbar (12;32).

7. Means of attachment according to claim 6, characterized in that the slide plate (20;31) extends between the attach¬ ing points (18,19;28,29) and is of a rigid material, so that it forms a spacing means between the attaching points.

8. Means of attachment according to claim 1 for shaped roofing sheets, the mounting crossbar (12;32) being posi¬ tioned perpendicularly to the direction of the ridges of the roofing sheets (11) and the roofing sheets being attac¬ hed to the crossbar by means of screws (13,14), characteri¬ zed in that the crossbar (12;32) has such a low height (H2) that the roofing sheets can be applied close to the exis¬ ting roof surface, so that spot loads on the sheets can be distributed over a larger roof area.