Building panel and coupling system for such building panels

Description

[0001] The present disclosure relates to a roof structure comprising a coupling system for coupling sandwich building panels, the building panels comprising two cover sheets and a core of insulating material sandwiched between the two cover sheets.

[0002] DE 8803615 and US 5,613,338 disclose examples of such a building panel for a roof structure. Other examples are sandwich panels available from SAB-profiel BV, the Netherlands, such as the SAB WB and SAB W panels. These sandwich panels are designed as wall panels, with the coupling edges extending vertically. If such building panels are used for roofing, the coupling edges are horizontal or inclined and exposed to ingress of rain water. Therefore, the joints must be sealed to prevent leaking of rainwater or melting snow. Usually, one or two parallel seals are applied, extending along the full length of the joint. This requires large amounts of sealing compound. One sealing must be applied before mounting and one after placing of the roofing, so the job is labour-intensive. Sealing compounds must be applied under favourable weather conditions, which means that it must not be too cold or rainy. Even dew can limit daily mounting hours for application of the sealing compounds.

[0003] It is an object of the invention to provide building panels which are more suitable for use in a non-vertical position, in particular for building a roof which is less sensitive for water leakage.

[0004] The object of the invention is achieved with a roof structure according to claim 1.

[0005] Rather than trying to fully block any leakage of water, the water discharge channel discharges water seeping between the coupling edges. By coupling the building panels, the coupling edges enclose the water discharge channel, viewed in cross section. When mounted, building panels of roofing structure are typically inclined and mounted side by side, so the coupled edges are also inclined. Hence, water collected in the water discharge channel flows down to an open lower end of the discharge channel where the water can be collected, e.g., in a gutter. The top end of the water discharge channel can be capped, e.g., by a ridge, and / or sealed to avoid direct ingress of rain water.

[0006] The cover sheets typically include an inner cover sheet and an outer cover sheet. The outer cover sheet is configured for outdoor conditions, e.g., the outer cover sheet may for example be thicker than the inner cover sheet and / or be provided with a weather resistant coating, while the inner cover sheet is configured for indoor conditions. The cover sheets are typically parallel and aligned to form building panels of substantially even thickness which can be coupled to form a substantially flush surface.

[0007] The coupling system of the roof structure comprises one or more compressible seals between the coupling edges at a position between the water discharge channel and the outer cover sheets. As a result, the main part of the rain water will be blocked by the seal and will flow from the roof, while the water discharge channel or channels are needed only for the discharge of water seeping through the seal. Combining a seal with a water discharge channels facilitates efficient management of water.

[0008] At the coupling edges of the building panel, the cover sheets have bent sheet edges piercing into the insulating material. This way, sharp edges of the sheets are shielded by the insulating material. It also serves to avoid any thermal bridges between the inner and outer cover sheets. Moreover, such bent edges provide resiliency during coupling and improve the clamping fit between two coupled coupling edges.

[0009] With such building panels having inwardly bent and shielded cover sheet edges, the coupling edge of one of the building panels is a female coupling edge recessed between the two bent sheet edges, while the coupling edge of the other building panel is a matching male coupling edge with the bent edges being offset from the outer surfaces of the panel, so as to form a projection fitting within the recess of the female coupling edge. The male and / or female coupling edge is provided with a recess for forming the water discharge channel extending substantially parallel to the coupling edges.

[0010] The female coupling edge is offset from an exterior surface of the building panel, while the male coupling edge comprises a flange extending the outer surface of the building panel, and overlapping the female coupling edge, so as to be flush with the outer surface of the building panel with the female coupling edge. The flange overlaps the water discharge channel.

[0011] Optionally, the overlapped water discharge channel can be configured to receive a fastener in a sunk manner, e.g., a fastener serving to bolt the panel to a roof support. This way, the water discharge channel and the fasteners are hidden from view, and the roof has a smooth appearance, allowing rain water and snow top slide off the roof without obstacles.

[0012] In a specific embodiment the overlapping flange may have a stepped cross section with an outer tip of reduced thickness and a main part of increased thickness, the main part overlapping the water discharge channel, the outer tip matching a recess in the female coupling edge and overlapping the compressible seal. The compressible seal can for example be partly received in a matching recess.

[0013] The compressible seal can be any suitable type of seal, including but not limited to hollow strips or hoses, e.g., of a rubber or elastomeric material.

[0014] Optionally, an additional compressible sealing strip can be compressed by a transversal surface bridging the outer tip and the main part of the overlapping flange of the male coupling edge.

[0015] An alternative, or additional, water discharge channel can be formed in one or more recesses used for coupling the building panels. For example, the bent sheet edges of the female coupling edge can be received in respective matching recesses in the male coupling edge, one or both of the recesses being extended to form a water discharge channel. The recess with the water discharge channel can for example be adjacent the overlapping flange of the male coupling edge.

[0016] The insulating material of the building panels can for example comprise polyisocyanurate (PIR), polyurethane (PUR) or any other suitable insulating material. The cover sheets are typically sheets of a suitable coated steel, e.g., of about 0,5 - 1 mm thickness. Other materials, such as aluminium and / or other thicknesses can also be used of so desired.

[0017] The coupling system can be realized using building panels comprising at least one male and / or female coupling edge of the coupling system of any one of the claims. In a specific embodiment the building panel comprises a male coupling edge at one side and a female coupling edge at an opposite side of the building panel.

[0018] The roof structure comprises coupled building panels mounted side by side on a roof support, e.g., with the coupling edges being inclined extending from one or both side of a roof ridge to respective lower edges. The lower edges of the roof structure may be provided with a gutter. The upper and lower edges of the building panels can be covered to protect the insulating layer or for decorative reasons.

[0019] The above-described aspects will hereafter be more explained with further details and benefits with reference to the drawings showing a number of embodiments by way of example. Figure 1: shows in cross section a coupling system for building panels of a roof structure according to the present invention; Figure 2: shows a roof structure according to the present invention; Figure 3A: shows an alternative embodiment; Figure 3B: shows the panels of Figure 3A after coupling.

[0020] Figure 1 shows an embodiment of a coupling system 30 for a roof structure according to the invention. The coupling system couples two building panels 31, 32, both comprising an interior cover sheet 33, 34 at an interior side 35, an outer cover sheet 36, 37 at an exterior side 38, and a core 39 of an insulating material, such as PIR or PUR, sandwiched between the inner and outer cover sheets 33, 36; 34, 37.

[0021] The building panels 31, 32 having matching coupling edges 40, 41. The cover sheets 33, 36; 34, 37 have bent sheet edges 42, 43, 44, 45 at the coupling edges 40, 41. The bent sheet edges 42, 43, 44, 45 pierce into the insulating material of the core 39 of the respective building panel 31, 32.

[0022] The coupling edge 41 of one of the building panels 32 is a female coupling edge with a coupling recess 46 between the two bent sheet edges 42, 43. The coupling edge 40 of the other building panel 31 is a male coupling edge with the bent sheet edges 44, 45 being offset from the interior and exterior surfaces 35, 38 of the building panel 31, so as to form a coupling projection 47 fitting within the coupling recess 46 of the female coupling edge 41. In this embodiment, the coupling projection 47 of the male coupling edge 40 is flanked by a smaller flange 48 at the interior side 35 of the building panel 31 and a larger flange 49 at the exterior side 38 of the building panel 31. Between the smaller flange 48 and the coupling projection 47 is a first recess 50 receiving a bent sheet edge 43 of the female coupling edge 41. Similarly, between the larger flange 49 and the coupling projection 47 is a second recess 51 receiving a bent sheet edge 42 of the female coupling edge 41. The short flange 48 is flush with the outer surface of the interior side 35 of the two building panels 31, 32, while the larger flange 49 is flush with the outer surface of the exterior side 38 of the two building panels 31, 32.

[0023] The female coupling edge 41 is offset from the exterior surface 38 of the building panel 32 to form a recess 52 receiving the larger flange 49 of the male coupling edge 40.

[0024] The larger flange 49 of the male coupling edge 40 and the matching recess 52 of the female coupling edge 41 have a matching stepped configuration. Hence, the larger flange 49 has a main part 53 and an outer tip 54 of reduced thickness. At the exterior side 38 of the flange 49, the tip 54 is flush with the main part 53 and the outer surface of the remainder of the building panel 31. At the opposite side of the flange 49, a transversal face 55 closes the outline between the tip 54 and the main part 53. Similarly, the matching recess 52 has a first surface 56 facing the main part 53 of the flange 49, a second surface 57 facing the transversal surface 55 of the flange 49, and a third surface 58 facing the outer tip 54.

[0025] This first surface 56 is provided with a water discharge channel 59 running substantially parallel to the coupling edges 40, 41, i.e., in a direction perpendicular to the drawing. The main part 53 of the larger flange 49 of the male coupling edge 40 overlaps the water discharge channel 59, thus closing the water discharge channel 59 in cross section.

[0026] The overlapped water discharge channel 59 is configured to receive the bolting heads of one or more fasteners 60 in a sunk manner. The fasteners 60 serve to mount the building panel 32 to a roof support. The overlapping flange 49 of the male coupling edge 40 hides the fasteners 60 from view.

[0027] The third surface 58 overlapped by the outer tip 54 of the flange 49 has a slot 61 receiving a compressible seal 62, formed by a rubber or rubber-like hose. The seal 62 and the slot 61 run substantially parallel to the coupling edges 40, 41. This seal 62 is between the water discharge channel 59 and the exterior surface 38 of the building panels 31, 32.

[0028] Between the transversal face 55 of the male coupling edge 40 and the second face 57 of the female coupling edge 41 is a compressible seal 63.

[0029] A second water discharge channel 64 is formed by a slot in the recess 51 between the larger flange 49 and the coupling projection 47 of the male coupling edge 40.

[0030] The building panels 31, 32 can be identical, having a male coupling edge 40 at one side and a female coupling edge 41 at the opposite side, so they can be mounted side by side.

[0031] Rain water falling upon the roof may seep into the joint between the two building panels 31, 32. This water will mainly be stopped by the first compressible seal 62. A minor portion of the water will pass the seal 62 and will be stopped by the seconds compressible seal 63. Water passing both seals 62, 63 is collected in the water discharge channel 59. Since this water discharge channel 59 is inclined, water will flow down to an open lower end of the water discharge channel 59 where it is collected, e.g., by means of a gutter. In the rare case that this water discharge channel 59 might overflow, the water will also be collected and discharged in the second water discharge channel 64.

[0032] Figure 2 shows schematically a roof structure 70 comprising a roof 71 with a roof ridge 72 and inclined building panels 73, e.g., the building panels of Figure 1 or any other type of building panels according to the invention. Each of the building panels 73 extend from the roof ridge 72 downwards to a gutter 74 on a support. The building panels 73 have oppositely arranged inclined coupling edges 76 and substantially horizontal upper and lower edges 77, 78. The upper edges 78 connect to the roof ridge 72 and are sealed off by a foam body 79 protecting the insulating cores and closing off the top ends of the water discharge channels of the respective coupling edges 76. The foam body 79 of the roof ridge 72 is capped by a flashing 80. The lower edges 77 of the building panels 73 are also covered by a matching profile 81 connecting the building panels 73 to the gutter 74.

[0033] Figures 3A and 3B show an alternative embodiment comprising a pair of building panels, in particular roof panels 141, 142 with matching coupling edges 143, 144. The two panels 141, 142 comprise a core 145 of an insulating material sandwiched between an outer cover sheet 146 forming the exterior roof surface, and an inner cover sheet 147 facing the roofed interior space.

[0034] The coupling edge 143 of the panel 141 shown left in the drawing is a female coupling edge, while the coupling edge 144 of the other panel 142 is a male coupling edge. The cross section shown in Figures 3A and 3B is substantially constant over the length of the coupling edges 143, 144.

[0035] The cover sheets 146, 147 of both panels 141, 142 have sheet edges, which are bent inwardly (i.e., towards a center face X' of the panel 141, 142) to form projections 148A, 148B, 149A, 149B extending substantially parallel to the outer surfaces of the cover sheets 146, 147 of the panels 141, 142.

[0036] The female coupling edge 143 of the left panel 141 comprises the two projections 148A, 148B and a coupling recess 151 between the two projections 148A, 148B. The coupling recess 151 comprises a compressible foam backbone 152 between the two projections 148A, 148B and extending over the full length of the coupling edge 143. The projections 148A, 148B are offset from the rest of the respective cover sheets 146, 147 to define receiving recesses 153, 154 for receiving the respective projections 149A, 149B of the male coupling edge 144, in such a manner that the outer coversheets 146 of the two panels 141, 142 are flush with each other, just as the inner cover sheets 147.

[0037] The male coupling edge 144 comprises the projections 149A, 149B, a middle protrusion 155, a first recess 156 between the projection 149A and the middle protrusion 155, and a second recess 157 between the projection 149B and the middle protrusion 155. The first recess 156 is configured to receive the projection 148A of the female coupling edge 143. The second recess 157 is configured to receive the projection 148B of the female coupling edge 143. The middle protrusion 155 of the male coupling edge 143 forms a tight clamping fit with the coupling recess 151 of the female coupling edge 144.

[0038] At the male coupling edge 143, the sheet edge of the outer cover sheet is bent inwardly with a U-turn to form the projection 149A. At the root of this projection 149A, the sheet edge is again bent inward to define a broadest width of the first recess 156 which is larger than the width of the received projection 148A. Then, the sheet edge is bent back to an outer end of the middle protrusion 155 at an inclination angle such that the width of the first recess 156 between the tips of the middle protrusion 155 and the projection 149A is less than the broadest width. When the two panels 141, 142 are mated, the projection 148A fits in the narrower opening of the first recess 156, but at the broader part of the first recess 156 a first water discharge channel 158 is defined between the projection 148A of the female coupling edge 143 and the middle protrusion 155 of the male coupling edge 144.

[0039] The projection 148A extending from the outer cover sheet 146 of the female coupling edge 143 has a root section 159 and a receding tip 160. When mated, the root section 159 engages the tip of the projection 149A while the receding tip 160 is spaced from the projection 149A of the male coupling edge 144. In this position the receding tip 160 and the projection 149A jointly define a seal receiving recess 161. A seal 162 is received in the seal receiving recess 161.

[0040] In the second recess 157 of the male coupling edge 143, the projection 148B has a substantially flat surface. The projection 149B has a concave or kinked surface facing the projection 148A to form a concavity 163. When the two coupling edges 143, 144 are mated, this concavity 163 and the projection 148B of the female coupling edge 144 jointly enclose a second water discharge channel 164 running along the length of the coupling edges 143, 144.

[0041] Rain water or melting snow seeping into the coupling is primarily blocked by the seal 162. Water that still passes the seal 162 is collected and discharged in the first water discharge channel 158. If part of the water still leaks through, it is collected and discharged via the second water discharge channel 164.

[0042] The disclosure is not restricted to the above described embodiments which can be varied in a number of ways within the scope of the claims.

Claims

1. Roof structure comprising building panels and a coupling system (30) for coupling the building panels (31, 32) the building panels comprising two cover sheets (33 34, 36, 37) including an inner cover sheet (33, 34) and an outer cover sheet (36, 37), and a core of insulating material sandwiched between the two cover sheets; wherein the building panels are mounted side by side on a roof support, the building panels having matching coupling edges (40, 41), wherein the coupling edges are inclined extending from one or both sides of a roof ridge to respective lower edges, wherein the coupling edges are profiled to define one or more water discharge channels (59, 64) running substantially parallel to the coupling edges, and the coupling system comprises one or more compressible seals (62, 63) between the coupling edges at a position between the one or more water discharge channels (19; 59, 64) and the outer cover sheets, wherein the cover sheets have bent sheet edges (42, 43, 44, 45) at the coupling edges, the bent sheet edges extending into the core (39) of insulating material; wherein the coupling edge of one of the building panels is a female coupling edge (41) recessed between the two bent sheet edges (42, 43), and the coupling edge of the other building panel is a male coupling edge (40) with the bent sheet edges (44, 45) being offset from the outer surfaces of the building panel, so as to form a coupling projection (47) fitting within the coupling recess (46) of the female coupling edge; wherein at least one of the male and female coupling edges is provided with the water discharge channel (59, 64) extending substantially parallel to the coupling edges (40, 41); wherein the female coupling edge (41) is offset from an exterior surface (38) of the building panel and wherein the male coupling edge comprises a flange (49) extending the outer surface of the building panel (31) with the male coupling edge (40), and overlapping the female coupling edge (41) so as to be flush with the outer surface of the building panel (32) with the female coupling edge, characterized in that the water discharge channel (59) is overlapped by the flange (49) of the male coupling edge.

2. Roof structure according to claim 1, wherein the overlapped water discharge channel (59) is configured to receive a fastener (60) in a sunk manner.

3. Roof structure according to claim 2, wherein the overlapping flange (49) has a stepped cross section with an outer tip (54) of reduced thickness and a main part (53) of increased thickness, the main part overlapping the water discharge channel (59), the outer tip matching a recess in the female coupling edge (41) and overlapping the compressible seal (62).

4. Roof structure according to claim 3, wherein the compressible seal (62) is partly received in a matching recess (61).

5. Roof structure according to claim 3 or 4, wherein the compressible seal (62) is a hollow strip or hose.

6. Roof structure according to claim 3, 4 or 5, comprising a compressible sealing strip (63) compressed by an edge (55) between the outer tip (54) and the main part (53) of the overlapping flange (49) of the male coupling edge.

7. Roof structure according to any one of the preceding claims, wherein at least one of the bent sheet edges (42) of the female coupling edge (41) is received in a matching recess (51) in the male coupling edge (40), the recess being extended to form a water discharge channel (64).

8. Roof structure according to claim 7, wherein the recess (51) with the water discharge channel (64) is adjacent the overlapping flange (49) of the male coupling edge (40).