NO20180177A1

NO20180177A1 - A sandwich panel and system thereof

Info

Publication number: NO20180177A1
Application number: NO20180177A
Authority: NO
Inventors: Jan-Christer Mäki
Original assignee: Lindab Ab
Priority date: 2015-07-28
Filing date: 2018-02-02
Publication date: 2018-02-02
Also published as: WO2017016833A1; SE1551043A1; SE539184C2

Abstract

The present invention relates to a sandwich panel (10) and a system of such panels (10) for isolation of a building, each panel (10) comprising an external plate (13) and an internal plate (12) with intermediate isolation (33) between the plates (12, 13), where the sandwich panel (10) comprises at least one expansion section (14) and where at least an upper edge (21) of the external plate (13) has a hook-shape (21) for attaching to a fastening stud (19) and at least an lower edge (20) of the external plate (13) has a groove-shape (20) for receiving the hook-shape (21) such that sandwich panels (10) may be stacked to a system forming an isolating layer.The present invention relates to a sandwich panel (10) and a system of such panels (10) for insulation of a building, each panel (10) comprising an external plate (13) and an internal plate (12) with intermediate insulation (33 ) between the plates (12, 13), where the sandwich panel (10) comprises at least one expansion section (14) and where at least an upper edge (21) of the external plate (13) has a hook-shape (21 ) for attaching to a fastening stud (19) and at least an lower edge (20) of the external plate (13) has a groove-shape (20) for receiving the hook-shape (21) such that sandwich panels (10) may be stacked to a system forming an isolating layer.

Description

A SANDWICH PANEL AND SYSTEM THEREOF

The present invention relates to a sandwich panel and a system of at least two such panels for isolation of a building e.g. at renovation. The sandwich panels of the system comprise an external plate and an internal plate with intermediate isolation material arranged between the plates. The internal plate comprises at least one expansion section in a load bearing direction. An upper edge of at least the external plate has a hook-shape for attaching to a fastening stud. The lower edge of at least the external plate has a grooveshape for receiving the hook-shape of another plate such that sandwich panels may be stacked to form an isolating layer.

Background of the invention

Sandwich elements are used in the construction industry primarily for outer walls and roofs. Industrial buildings typically comprise a body of pillars and laying sandwich element extending between the pillars and stacked on top of each other to form isolating outer walls. However, these systems are commonly associated with a number of problems. Firstly, it may occur that an external plate and an internal plate of the sandwich panel do not expand uniformly, having the result that the sandwich panel may bend outwards e.g. during warm summer conditions orinwards e.g. during cold winter conditions. This phenomenon typically arises when the external plate is subject of thermal expansion due to heating e.g. due to exposure to the sun while the internal plate is subjected to less heat and thereby less expansion than the external plate.

A further problem which may be encountered by sandwich panel systems according to the prior art are so-called thermal bridges. The effect may for example arise when sandwich panels are mounted to a surface or pillar by means of thoroughgoing fastening means of attachment such as screws and bolts, rivets or like means which provide a thermal link, often referred to as a bridging of cold, between the ambient air and the surface of attachment. A thermal bridge may thus counteract the isolating capability of the sandwich panel system.

A yet further problem which stem from the same principle as a thermal bridge is that of moisture conductivity of thoroughgoing means of attachment, which attachment or like may allow moisture to migrate from moist or wet ambient conditions through the isolating layer into the surface of attachment and inner space via the channel created by the thoroughgoing means.

Brief description of the invention

It is an object of the present invention to provide a sandwich panel and a system made up of at least one or more such panels, which solve or at least mitigate the problems of such a panel and systems taught in the prior art.

One object of the present disclosure is achieved by providing a sandwich panel for isolation of a building, said panel comprising an internal plate, an external plate, a core of isolating material arranged between said plates and connected/fixed thereto, i.e. to said plates, e.g. mechanically and/or by being moulded; melted and cured; or adhered thereto. The internal plate of the panel comprises at least one expansion section extending in a loadbearing direction of said sandwich panel between a lower edge and an upper edge of said internal plate, and wherein/which at least one expansion section is adapted to facilitate horizontal lengthwise play of said internal plate in response to a corresponding lengthwise thermal expansion of said external plate in response to a corresponding/inwards transferred lengthwise thermal expansion of said external plate. This inventive individual panel enjoys advantages corresponding to the ones for the panel system comprising more than one such panel when assembled.

Another object of the present disclosure is achieved by providing a sandwich panel system for isolation of a building, the system comprising a plurality of sandwich panels each comprising an internal plate, an external plate, an isolating material arranged between the plates and connected/fixed thereto, i.e. to said plates, e.g. mechanically and/or by being moulded; melted and cured; or adhered thereto and wherein said internal plate comprises at least one expansion section extending in a loadbearing direction of the sandwich panel between a lower edge and an upper edge of said internal plate and wherein said expansion section is adapted to facilitate horizontal lengthwise play of the internal plate in response to a corresponding lengthwise thermal expansion of the external plate.

The expansion sections of the sandwich panels may be adapted to provide a certain play in terms of a horizontal longitudinal length of the internal plate. One object of facilitating such play is that an internal plate may to a certain extent expand in response to a corresponding thermal expansion of an external plate, as the external plate is e.g. subjected to heating, transferred inwards to the internal plate.

According to one aspect, the expansion sections are only arranged in a loadbearing direction of the sandwich panel.

A further object of the present disclosure is achieved by providing a fastening stud which aligns a panel vertically, from which a panel may be suspended and on which stud a panel may rest and which fastening stud does not extend though the whole panel or through the external plate to an external side of the panel layer.

A further object of the present disclosure is achieved by providing a sealing strip in the upper and/or lower edges of the external plate.

According to one aspect, the at least one expansion section or said or each section may comprise at least one pleat.

The pleat or fold is configured such that it may provide the internal plate with a certain amount of stretch such that the plate attains a function similar to that of an accordion in that it is capable of expanding and contracting in response to a corresponding expansion or contraction of the external plate.

In order to facilitate such movements, the intermediate isolation material may be resilient or porous enough to allow the expansion or contraction without exerting sufficient resistance or counter force to hinder stretching and/or movements of the internal and/or external plate.

According to one aspect, the pleat is configured such that it is flush with the internal plate of the panel and does not protrude out from the internal plate of the panel.

According to one aspect, the thickness of the internal plate may be made thinner at the locations where the pleats are disposed such as to facilitate easier expansion of the pleats.

The distance between the expansion sections or the number of expansion sections per unit length of the sandwich panel may differ depending on the appliance of the sandwich panel system and dimensions of each panel. An environment characterised by large differences in temperature may for example require a larger number of expansion sections and/or the distance between the expansion sections to be relatively smaller or that expansion sections are capable of more expansion individually.

According to a further aspect, the internal plate may be comprised of one or more partial plates. According to a further aspect, the expansion section comprises at least one gap between the partial plates. According to yet a further aspect, the internal plate comprises one or more partial plates and the expansion section comprises at least one gap between the partial plates.

By arranging a gap between the partial plates, the partial plates of which the internal plate is comprised, may be allowed to expand without interfering with each other or allowed to be parted in response to an expansion of the external plate.

According to still a further aspect, the expansion section comprises overlapping of the partial plates. According to a further aspect, the internal plate may be comprised of one or more of partial plates wherein the expansion sections comprises overlapping of the partial plates.

By arranging an overlap between the partial plates, the partial plates of which the internal plate is comprised, may expand without restraining each other or be parted in response to an expansion of the external plate.

According to a further aspect the external plate may have an upper edge and a lower edge, the upper edge having a hook-shape and the lower edge having a groove-shape. According to a further aspect the hook-shape and/or said groove-shape extend along the length of said upper edge and/or said lower edge of the sandwich panel . According to a further aspect, the external plate may have an upper edge where the upper edge may have a hookshape. The hook-shape may have an opening towards the internal plate. According to a further aspect, the external plate may have a lower edge where the lower edge has a groove shape.

The hook may feature resilience, for receiving a fastening stud in a resilient attachment. The hook-shape may extend along a length of the upper edge of the sandwich panel and the groove-shape may extend along a length of the lower edge of the sandwich panel.

The groove-shape for receiving the hook-shaped upper edge may preferably have a width corresponding substantially to the width of the hook-shaped upper edge or slightly smaller. A slightly smaller groove-shape may have the result that parts of the periphery of a hook-shaped edge resiliently abut the inside of a groove-shaped edge. Such resilience may assure a proper seal between an upper edge of a first sandwich panel/plate and a lower edge of another sandwich panel/plate.

According to a further aspect, the sandwich panel may be suspended and aligned vertically by means of said groove-shape being configured to receive a hook-shape or a fastening stud and said hook-shape being configured to engage with a fastening stud. The engagement may be resilient in that the hook-shape is biased when receiving a fastening stud.

According to a further aspect, the fastening stud extends lengthwise along a substrate and/or a sandwich panel. According to a further aspect, the sandwich panel may be suspended and/or aligned vertically by means of the groove-shape being configured to receive a hook shape and/or a fastening stud. According to a further aspect, the hook-shape and said groove-shape and said fastening stud forms a lengthwise extendable/extending joint.

According to a further aspect the joint comprises a seal strip between the groove-shape and said hook-shape such that a water tight joint is achieved.

According to a further aspect, the joint, the hook-shape and the grooveshape are displaceable in a lengthwise direction of the fastening stud in response to a lengthwise expansion of a sandwich panel.

According to a further aspect, the sandwich panel slidably rests on the fastening stud or is slidably suspended by the fasteing stud. Slidably resting or suspended here imply that the fastening stud is capable of supporting the weight of a sandwich panel while allowing for the panel to slide along the fastening stud in a longitudinal direction of the fastening stud. The above described interplay between the design of the upper and lower edge of the external plate of the sandwich panel having a hook and groove shape and the fastening stud, allows for an expansion or contraction of the sandwich panel in response to thermal conditions, thereby the movement of a panel is unconstrained in a horizontal direction in parallel with the substrate when attached to a substrate. It may here be emphasized that an expansion of the external plate may give rise to forces in the core of the sandwich panel which cause the expansion sections to expand and thereby also the internal plate, thus, the external plate may indirectly stretch or pull out the expansion sections of the internal plate.

According to a further aspect, the fastening studs may extend in a plane transverse a substrate and extend horizontally parallel to the surface such as to provide support and/or suspension of at least one sandwich panel.

In further aspects, the internal plate may be comprised of different materials such as wood, metal, plastic, composites or recycled material etc.

Another object of the present disclosure is achieved by providing a sandwich panel for isolation of a building, the panel comprising an internal plate, an external plate, a core of isolating material arranged between and connected and/or fixed to the plates, e.g. mechanically and/or by being moulded; melted and cured; or adhered thereto. The internal plate of the panel comprises at least one expansion section extending in a loadbearing direction of the sandwich panel between a lower edge and an upper edge of the internal plate, which at least one expansion section is adapted to facilitate horizontal lengthwise play of the internal plate in response to a corresponding lengthwise thermal expansion of the external plate. This inventive individual panel enjoys advantages corresponding to the ones for the panel system comprising more than one such panel when assembled.

In one object of the invention, if more than one sandwich panel is utilised, i.e. if at least two sandwich panels are assembled side-by-side or in serial or end to end or after each other in a system, the possibility/range of expansion is at least doubled compared to only one sandwich panel if the at least two sandwich panels correspond to each other. If at least two sandwich panels that are to at least some extent different in dimension, or have a differing/varying number, size and shape of their expansion sections and similar parameters are assembled into the sandwich panel system, the extent/amount of expansion of these panels together is of course proportional to/dependent on these varying parameters and achieves a great flexibility and ability to be adapted to any surroundings, hot (high surrounding temperatures and/or high solar incident radiation) or cold (low temperatures, i.e. above or below or close to or at freezing point, e.g. zero degrees).

In another aspect, the sandwich panel system comprises at least two sandwich panels according to any preceding aspect.

In a further aspect the invention relates to a method of assembling a sandwich panel system comprising the steps of providing a first fastening stud on a substrate; arranging a first sandwich panel according to any preceding aspect such that a groove-shaped lower edge of said first panel receives the fastening stud; and providing a second fastening stud on the substrate such that a hook-shaped upper edge of the first sandwich panel receives the second fastening stud.

According to a further aspect, the method further comprises the steps of arranging a second sandwich panel such that a groove shaped lower edge of the second panel receives the hook-shaped upper edge of said first panel; and providing a third fastening stud on said substrate such that a hookshaped upper edge of said second panel receives said third fastening stud.

In another aspect the invention relates to the method utilising a second sandwich panel according to any preceding aspect.

The inventive method of the sandwich panel system achieves interplay between the sandwich panels and the fastening studs in that the panels are unconstrained in their respective engagement with the fastening studs and/or each other in a lengthwise direction. The assembly of interconnecting individual sandwich panels and fastening studs is facilitated as the interplay makes the system of panels more forgiving regarding tolerances between the entities when mounted and during varying ambient conditions, e.g. starting mounting the panels and studs at lower temperatures, e.g. in the morning, and finishing in the middle of the day at high temperatures has no negative effect as the panels may expand freely along the studs without jamming at joints or be hindered by any stud or unevenly bent, similar to heat distortion.

In another aspect, the method according to any preceding aspect further comprises the step of arranging at least one sandwich panel with a length different than the first sandwich panel above or below or side-by-side of the first sandwich panel at assembly.

In still another aspect, the method according to any preceding aspect further comprises the step of arranging the at least one sandwich panel with the different length with its short or long side/edge in engagement with a side/end of the first sandwich panel.

Further objects, features, advantages and properties of the sandwich panel system and method according to the invention will become apparent from the detailed description.

Brief description of the drawings

In the following detailed portion of the present description, the invention will be explained in more detail with reference to the exemplary aspects shown in the drawings, in which:

Fig. 1 is a perspective depiction of a sandwich panel according to the present invention.

Fig. 2a is a perspective depiction of a sandwich panel comprising an embodiment of an expansion section.

Fig. 2b is a planar cross-section of a sandwich panel comprising a pleated embodiment of an expansion section.

Fig. 2c is a planar cross-section of a sandwich panel comprising an overlapping embodiment of an expansion section.

Fig. 2d is a planar cross-section of a sandwich panel comprising an embodiment of an expansion section comprising a gap.

Fig. 3a is a perspective cross sectional depiction of an upper part of a sandwich panel according to the invention.

Fig. 3b is a perspective cross sectional depiction of a lower part of a sandwich panel according to the invention.

Fig. 4a is a diagrammatic depiction of a method of sandwich panel assembly according to the invention.

Fig. 4b is a diagrammatic depiction of a method of sandwich panel assembly according to the invention.

Fig. 4c is a diagrammatic depiction of a method of sandwich panel assembly according to the invention.

Detailed description of the invention

In the following detailed description, a sandwich panel 10 and a system 25 of such panels according to the invention will be described. Fig. 1 to 4c show the inventive sandwich panel 10, which may, as a typical non-limiting example measure from 0,5 m to 2 m or preferred from 1 m to 1.2 m in height and 5 to 9 m in a lengthwise direction A. The panel may be comprised of two outer layers 12, 13 of stainless, galvanised and/or painted steel plate with a core 33 of isolation material arranged there between. The core 33 may typically be comprised of mineral wool or expanded polystyrene.

According to the invention, the isolation material of the core 33 may be arranged between the internal plate 12 and the external plate 13 by means of fixation, e.g. by moulding, melting and curing, mechanical adhesion or other means of attachment, such as adhesive compounds. The thickness of the core 33 may typically range from 10 - 100 mm or be in other dimensions depending on the desired characteristics of the sandwich panel 10.

The expansion sections 14 extend in the loadbearing direction indicated by double arrow B from a lower edge 26 of the internal plate 12 to an upper edge 27 or the internal plate 12. The number of expansion sections 14 illustrated in Figure 1 is for exemplary purposes only. The number of expansion sections 14 on each panel 10 is at least one. In Figure 1 there is shown seven expansion sections 14, but the panel 10 could comprise between one and twenty or preferred two to fifteen expansion sections 14, but this number depends among others on the length of the panel itself, the expansion characteristics of the materials making up each panel, and the required/calculated amount of expansion that the panel may be subjected to/has to adapted to due to surrounding temperatures or the like.

Figure 2a, illustrate a limited part of a sandwich panel 10 according to the invention comprising at least one expansion section 14 further comprising a pleat 15.

Figure 2b, illustrates a top cross-sectional view of a limited part of a sandwich panel 10 according to the invention comprising an internal plate 12, an external plate 13 and at least one expansion section 14 further comprising a pleat 15. The dimensions of the pleat may as a typical non-limiting examples range from 6 - 10 mm, the depth of the pleats typically extend 4-8 mm into the core 33 and the pleats typically dimensioned such as to provide a lengthwise play of 1 mm or more per meter sandwich panel 10 length.

Figure 2c, illustrates a top cross-sectional view of a limited part of a sandwich panel 10 according to one aspect of the invention comprising an internal plate 12, an external plate 13 and at least one expansion section 14 further comprising an overlap 16 between partial plates 24. The overlap may for example be in the range of 5 mm.

Figure 2d, illustrates a top cross-sectional view of a limited part of a sandwich panel 10 according to one aspect of the invention comprising an internal plate 12, an external plate 13 and at least one expansion section 14 further comprising a gap 17 between partial plates 24. The gap may be dimensioned as a column, gap or slit along the whole length of the internal plate 12 or it may comprise a perforation along only a part of the length and/or height of the internal plate or a combination, i.e. a slit beside perforations.

As shown in Figure 3a, the external plate 13 has a hook-shaped upper edge 21. Inside the hook-shape of the upper edge 21 there may in one aspect be arranged a sealing strip 18 extending continuously along the length of the upper edge 20.

As shown in Figure 3b, the external plate 13 has a groove-shaped lower edge 20. Inside the groove-shape of the lower edge there may in one aspect be arranged a sealing strip 18 extending continuously along the length of the lower edge 20.

A sealing strip in the upper 21 and/or lower 20 edges of the external plate 13 may contribute to the isolation capacity of the panel system 25 in that the joint 28 between two sandwich panels 10 provide a water tight seal.

In further aspects of the invention, also the edges of the internal plate 12 comprise corresponding hook and groove shapes or a tongue and groove shape such that the sandwich panels may be stacked on each other to form an isolating wall.

Figures 4a-c illustrate an aspect of the sandwich panel system 25 comprising at least one fastening stud 19. The fastening stud 19 comprises an inner part 32 attached to a substrate 11 , an intermediate part 31 and an outer part 30. The transitions between the parts 30, 31 , 32 typically constitute right angles although they may be altered or inclined in other angles in relation to each other to ensure proper function of the sandwich panels 10 and the system 25. The fastening stud 19 or plurality of fastening studs 19 typically extend along the lengthwise extension of the substrate 11 and/or the sandwich panel 10 and/or a plurality of substrates/sandwich panels 11/10.

The fastening stud 19 may engage with a hook-shaped upper edge 21 or a groove-shaped lower edge 20 individually or simultaneously to form a joint 28 which may comprise a sealing strip 18 as depicted in Fig 4 a-c. The system 25 thereby achieves that the internal plates 12 and the external plates 13 of the sandwich panels 10 are unconstrained in their respective lengthwise and/or broad wise direction as they expand or collapse. Depending on if the panels 10 are stacked standing or laying down when being larger in one direction, the internal plate 12 of the sandwich panels may slide and be displaced in a lengthwise direction along the fastening stud 19 as the internal plate slidably rest on the intermediate part 31 of the fastening stud 19. The hook-shaped upper edge 21 of the external plate may further slide in its engagement with the outer part 30 or the fastening stud 19 and/or the lower edge 20 of the external plate may alike slide in its engagement with a hookshaped upper edge 21 of a sandwich panel.

Thereby, the sandwich panel system 25 achieves interplay between the sandwich panels 10 and the fastening studs 19 in that the panels 10 are unconstrained in their respective engagement with the fastening studs 19 and/or each other in a lengthwise direction A.

Figures 4a-c provides schematic depictions of a method according to one aspect of the invention. In a first step at least one fastening stud 19 comprises an inner part 32, an intermediate part 31 and an outer part 30 is attached to a substrate 11. A first fastening stud 19 is provided on a substrate 11. The transitions between the parts 30, 31 , 32 of the fastening stud 19 typically constitute right angles although they may be altered or inclined in other relative angles to ensure proper function and assembly of the sandwich panels 10 and the system 25.

The fastening stud 19 is fastened to an arbitrary substrate such as substrate 11 by suitable means of attachment 29. The fastening stud 19 or a plurality of fastening studs 19 may extend along a preferred length of the substrate 11 depending e.g. on the width of the substrate 11 which is to be isolated. The fastening stud 19 extends longitudinally, i.e. along the length of the panel 10, in principle horizontally, along the substrate 11. In another aspect, the fastening stud 19 extends vertically, i.e. along the height/width of the panel 10 along the substrate 11 , if the panel extends vertically instead of horizontally as shown in Figs.1 to 4c.The fastening stud 19 is fastened to the arbitrary substrate 11 at certain positions determined by the surface of the substrate 11. The substrate 11 is continuous or discontinuous, e.g. a wall made of bricks or a wall having vertical or horizontal beams. The fastening stud 19 is for example fastened to the brick wall at positions along the stud being regular and/or evenly distributed along the length of the stud. The fastening stud 19 is for example transversely fastened to the wall of beams with attachments 29 at positions at the ends of the stud 19.

Following the first step, a sandwich panel/plate 10 is arranged on the fastening stud 19 such that the outer part 30 of the fastening stud is received by a groove-shaped lower edge 20 of an external plate 13 of the panel 10, preferably having a sealing strip 18 arranged between the lower edge 20 and the outer part 30 of the fastening stud which is received by the lower edge 20 (see Fig 3b). In the resulting arrangement, the sandwich panel 10 rests on the fastening stud 19 while being aligned vertically and horizontally by the fastening stud and lower edge 20 while being able to slide along the length of the fastening stud 19. By arranging a first sandwich panel 10, the grooveshaped lower edge 20 of the first panel 10 receives the fastening stud 19.

In a subsequent step, the sandwich panel 10 is aligned and suspended at its hook-shaped upper edge 21 by means of a further fastening stud 19 (not shown). The fastening stud has the outer part 30 having the same height as the hook-shaped upper edge 21 , measured from the core 33 of the sandwich panel 10. The outer part 30 of the fastening stud 19 may be inserted into the hook-shaped upper edge 21 and subsequently rotated in the direction of arrow C, about its longitudinal axis such that the intermediate part 31 of the fastening stud 19 abut the core 33 of the sandwich panel 10 and the outer part 30 extend inside the hook-shaped upper edge 21. The further fastening stud 19 is subsequently fastened to the substrate 11. By providing a second fastening stud 19 on said substrate 11 , the hook-shaped upper edge 21 of the first sandwich panel 10 receives the second fastening stud 19.

In a following step, a second sandwich panel 10 is stacked on top of the further fastening stud 19 and the first sandwich panel 10 in that the grooveshaped lower edge 20 of the second panel receives the hook-shaped upper edge 21 of the first sandwich panel 10, so that a joint 28 is created between the first and the second panel, as illustrated in Figure 4c. The joint 28, comprising the upper edge 21 , the fastening stud 19 and the lower edge 20 thereby provide a water tight joint which isolates against moisture without facilitating thermal bridging between the substrate 11 and the ambient 23. By arranging a second sandwich panel 10, the groove shaped lower edge 20 of the second panel 10 receives the hook-shaped upper edge 21 of the first panel 10. Then, a third fastening stud 19 is provided on the substrate 11 , whereby the hook-shaped upper edge 21 of the second panel 10 receives the third fastening stud.

By the shape of the fastening stud 19 and the method/way of fastening it to the substrate 11 , each panel 10 is supported/upheld/carried from one longside to the other longside instead of short side to short side as in prior art panels being fastened at their short sides to a substrate. This fastening stud 19 according to the invention eliminates the need of strong/sturdy fastening means at the short sides/ends of panel 10 as required when fastening prior art panels. The fastening stud 19 according to the invention eliminates any dependency to where the joints between panels 10 are positioned at the substrate 11 as the inventive panels 10 are able to be arranged/slid anywhere along the stud 19. This advantage is lacking for prior art panels as they must be placed with their short sides/ends at fixed positions, such as at the beams of a wall that are arranged at fixed distances to each other, and the prior art panels must have the same length, so that the ends of each panel reaches a beam to be able to fasten the ends of each panel to a corresponding beam. The inventive stud 19 and method/way of fastening it makes it possible to have panels of different lengths and/or positioned at different positions, i.e. the joints of the inventive panels 10 do not have to be aligned from one row of panels to another panel row. The stud 19 and method/way of fastening it makes it possible to have panels 10 of different lengths within the same panel row when assembled to the substrate 11. The inventive stud 19 and method/way of fastening it makes it possible to have panels 10 with short lengths and long lengths within the same panel row and/or between different panel rows when assembled. Hence, panels 10 according to the invention of varying lenghts are possible to mix in the same row and/or in different rows and/or over at least a part of or over the whole substrate 11 during and after assembly.

Hence, in one aspect, the way or method of assembling the sandwich panels 10 according to the invention further comprises the step of arranging at least one sandwich panel 10 with a length different than the first sandwich panel 10 above or below or side-by-side of the first sandwich panel at assembly.

Hence, in another aspect, the way or method of assembling the sandwich panels 10 according to the invention further comprises the step of arranging the at least one sandwich panel 10 with the different length with its short or long side/edge in engagement with a side/end of the first sandwich panel 10.

Claims

1. Sandwich panel (10, 25) for isolation of a building, said sandwich panel (10) comprising an internal plate (12), an external plate (13), a core of isolating material (33) arranged between said plates and fixed thereto, characterized in that said internal plate (12) comprises at least one expansion section (14) extending in a loadbearing direction (B) of said sandwich panel (10) between a lower edge (26) and an upper edge (27) of said internal plate (12) and wherein said at least one expansion section (14) is adapted to facilitate horizontal lengthwise (A) play of said internal plate in response to a corresponding lengthwise (A) thermal expansion of said external plate (13).

2. The sandwich panel according to claim 1, said expansion section (14) comprising at least one pleat (15).

3. The sandwich panel according to any claim 1 or 2, said internal plate (12) being comprised of one or more partial plates (24).

4. The sandwich panel according to claim 3, wherein said expansion section (14) comprises at least one gap (17) between said partial plates (24).

5. The sandwich panel according to claim 3, wherein said expansion section (14) comprises overlapping (16) of said partial plates (24).

6. The sandwich panel according to any preceding claim 1 - 5, said external plate (13) having an upper edge (21 ) and a lower edge (20), said upper edge (21) having a hook-shape and said lower edge (20) having a groove-shape.

7. The sandwich panel according to claim 6, wherein said hook-shape and/or said groove-shape extending along the length of said upper edge (21) and/or said lower edge (20) respectively.

8. The sandwich panel according to any claim 1 - 7, said sandwich panel (10) being suspended and aligned vertically by means of a groove-shape (20) being configured to receive a hook-shape (21) or a fastening stud (19) and said hook-shape being configured to engage with the fastening stud.

9. The sandwich panel according to claim 8, wherein said fastening stud (19) extends lengthwise along a substrate (11 ) and/or the sandwich panel

(10).

10. The sandwich panel according to any of claims 8 - 9, wherein said hookshape (21) and said groove-shape (20) and said fastening stud (19) form a lengthwise extending joint (28).

11.The sandwich panel according to claim 10, wherein said joint (28) comprises a seal strip (18) between said groove-shape (20) and said hook-shape (21 ) such that a water tight joint (28) is achieved.

12. The sandwich panel according to any claim 10 - 11, wherein said joint (28), said hook-shape (21) and said groove-shape (20) are displaceable in a lengthwise direction (A) of said fastening stud (19) in response to a lengthwise expansion of the sandwich panel (10).

13. A sandwich panel system (25) comprising at least one or more sandwich panels (10) according to any preceding claim.

14. Method of assembling a sandwich panel system (25) comprising the steps of:

- providing a first fastening stud (19) on a substrate (11 );

- arranging a first sandwich panel (10) according to any preceding claim such that a groove-shaped lower edge (20) of said first panel (10) receives said fastening stud (19); and

- providing a second fastening stud (19) on said substrate (11 ) such that a hook-shaped upper edge (21 ) of said first sandwich panel (10) receives said second fastening stud (19).

15. Method according to claim 13, further comprising the steps of:

- arranging a second sandwich panel (10) such that a groove shaped lower edge (20) of said second panel (10) receives said hook-shaped upper edge (21 ) of said first panel (10); and

- providing a third fastening stud (19) on said substrate (11 ) such that a hook-shaped upper edge (21) of said second panel (10) receives said third fastening stud (19).

16. Method according to claim 14 or 15, further comprising the step of:

- arranging at least one sandwich panel (10) with a length different than the first sandwich panel (10) above or below or side-by-side of the first sandwich panel at assembly.

17. Method according to claim 16, further comprising the step of:

- arranging the at least one sandwich panel (10) with the different length with its short and/or long side/edge in engagement with a side/end of the first sandwich panel (10).