AU717362B2 - Clip assembly - Google Patents

Description

'I

AUSTRALIA

Patents Act COMPLETE SPECIFICATION

(ORIGINAL)

Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority Related Art: Name of Applicant: Stramit Corporation Limited Actual Inventor(s): David John Lawrence Christopher Lee Healy Robert Charles Labbett Address for Service: PHILLIPS ORMONDE FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Invention Title: CLIP ASSEMBLY Our Ref 519101 POF Code: 100/169406 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): -1-

I

do CLIP ASSEMBLY BACKGROUND OF THE INVENTION The present invention relates generally to a clip assembly for the concealed fixing of roofing or other cladding sheets and to a clip assembly and cladding sheet for use in such a system. The application is a divisional application from the Applicant's copending applications nos. 64898/94, 64899194 and 74160/94; the contents of which are herein incorporated by cross reference.

Throughout the specification, the invention is described with reference to the orientation for use in roof cladding where the plane of the sheets is generally horizontal. This, however, should not be construed as limiting the invention to that orientation, as the cladding may be laid in other orientations. Accordingly, reference to a particular orientation is to be construed to encompass these other orientations.

Cladding sheets for concealed fixing have a plurality of longitudinal, re-entrant ribs, with pan sections between the ribs. The edges of the sheet are adapted for interengagement with the adjacent sheets, so that an end rib of one sheet fits over the end portion of the adjacent sheet.

The sheets are typically secured to the roof structure by elongated clips which secure the trailing edge end portion of the previously laid sheet and the end rib and intermediate ribs of the sheet to be laid. The clip has retaining formations spaced along the length thereof to coincide with the rib spacing. An endmost retaining formation of the clip is engaged with the trailing edge portion of the previously laid sheet, with the remainder of the clip extending in the direction of i l progress, and is fixed to the roof structure. The next sheet is then pressed onto 25 the clip so that the leading edge rib and intermediate ribs are engaged with the retaining formations and the leading edge rib also locks over the trailing edge portion of the previous sheet.

o°o The prior art clips are formed as a strap, which is folded to form a series of humps. The humps have detents for engagement with re-entrant portions of the ribs of the sheet.

o eI pa52817-9 8 specd.doc:17/0 SUMMARY OF THE INVENTION The present invention seeks to provide an improved cladding system. In particular an aim of the present invention seeks to provide a clip assembly which more securely fixes the cladding sheet to the roof structure and which is more easily able to be installed than prior art arrangements.

In a first aspect, the present invention relates to a clip assembly for use in the concealed fixing of a series of successively laid cladding sheets, said series including three successively laid sheets (hereinafter referred to respectively as the first, second and third laid sheet), said first, second and third laid sheets being of the type having a trailing edge portion, one or more intermediate ribs and a leading edge portion adapted for engagement with the trailing edge portion of a previously laid sheet, the clip assembly including a strap and a plurality of clips, said strap being elongate and including spaced apart first and second ends, an endmost one of said clips being adjacent said first end, and said other clips being located intermediate said first and second ends such that said strap forms a tail portion which extends beyond said other clips to said second end, said endmost clip being adapted for engagement with both the trailing edge portion of said first sheet and the leading edge portion of the second sheet, and said other clips being adapted for engagement with respective intermediate ribs of the second sheet, said tail portion being configured to underlie the region of engagement between the trailing t edge portion of said second sheet and the leading edge portion of the third sheet, said clip assembly further including locating means enabling the tail portion of the o* S clip assembly to locate the first end of a subsequent clip assembly relative to the o tail portion to provide correct positioning of said subsequent clip assembly relative to said clip assembly.

In the prior art clips the positioning and alignment of the clips had to be individually measured. No such measurement is required for the assembly of the t.oto.

above clip. This is of great practical benefit. With the assembly, the location of the straps on which the clips are positioned will determine this spacing. Further, installation of the sheeting is simplified over the prior art as the strap can be easily aligned along the roof structure through use of the locating means. In addition, as pa5281 7 9 8 specl.doc:7100 iP the endmost clip engages both the trailing edge portion of the previously laid sheet and the leading edge portion of the next sheet, a reference is created between the position of the clips and the location of the sheets which, in conjunction with the operation of the locating means, ensures that each clip assembly is correctly positioned relative to the sheets and clip assemblies which have been installed.

Further, the manufacturing tolerances of the sheets are typically much larger than the clip assemblies and the engagement arrangement of the endmost clip ensures that the leading edge of the overlapping sheet is not required to be held in place solely by engagement with the trailing edge of the underlapping sheet. Such an arrangement is undesirable as it provides an uncertain, and therefore, significantly weaker, fixing arrangement by virtue of the build up in the design tolerance which occurs by the overlapping of the sheets. A further advantage is that the strap can be used to press any insulation fitted below the deck.

Preferably the locating means includes a pair of apertures, one being disposed adjacent the first end, the other being disposed in the tail portion. In installation of the assemblies, the aperture in the tail portion is arranged to align with the aperture adjacent the first end of a strap of a subsequent clip assembly.

Preferably the pair of apertures are of similar dimensions in the direction of the strap to correctly position the assemblies on alignment of the apertures. Further, the apertures are designed to receive a fastener to secure the assemblies together.

*C.:Preferably on correct alignment of the leading edge of the clip assembly with a tail portion of a like clip assembly, the clip assemblies are adapted to overlap with the region of overlap underlying the endmost clip. Preferably the clip assemblies includes apertures which extend through respective ones of the clips and through the strap which underlies the respective clips. Preferably each aperture is arranged to receive a fastener to secure the clip assembly to the underlying ~structure and to secure the clip to the strap. A hexagonal head screw may be used as the fastener and the clip is configured to provide a space to enable access for 30 tightening of the screw to the underlying structure.

C Preferably the aperture in the endmost clip forms one of the pair of apertures of the locating means.

Preferably the strap includes a part extending from the first end formed as a downwardly facing channel and the tail portion includes an upwardly facing channel which forms at least part of the locating means which is adapted to receive the downwardly facing channel of the strap of a like clip assembly. In this way, the overlapping straps are able to nest together.

In a further aspect, the present invention relates to a concealed fix cladding system including cladding sheets of the type having spaced apart leading and trailing longitudinal edge portions and one or more ribs located intermediate the edge regions and extending along the sheet in the longitudinal direction, the cladding sheets being arranged to be laid in three successively laid series (hereinafter referred to respectively as the first, second the third laid sheets) with the leading edge portion of a said sheet being arranged to be juxtaposed to overlap with the trailing edge portion of a previously laid sheet to form a longitudinal rib at said overlapping edge region, and a clip assembly, the clip assembly including a strap and a plurality of clips, said strap being elongate and extending between spaced apart first and second ends, an endmost one of said clips being at or adjacent said first end and the or each of the other of said clips being located "20 intermediate said first and second ends such that said strap forms a tail portion which extends beyond said other clips to said second end, wherein in use, the strap is secured to an underlying structure and the clips are arranged to engage with associated ones of said cladding sheets so as to fix the cladding sheets to the underlying structure with said endmost clip engaging both the trailing edge portion 25 of said first sheet and the leading edge portion of the second sheet, and the other clips engaging with a respective one of the intermediate ribs of the second sheet, the tail portion being configured to underlie the region of engagement between the trailing edge portion of the second sheet and the leading edge portion of the third sheet, and wherein the clip assembly further includes locating means enabling the 30 tail portion of the clip assembly to locate the first end of a subsequent clip assembly relative to the tail portion in a predetermined position after securing of pa52817.98 speci.doc:l/1oo said second sheet, such that in installation of the system, the subsequent clip assembly is correctly positioned relative to the second sheet and the clip assembly by operation of the locating means and through engagement of the endmost clip of the subsequent clip assembly with the trailing edge portion of said second sheet.

A cladding system accordingly to this aspect of the present invention provides substantial benefits in installing the system and to the resulting performance of the system. In particular, by virtue of the fact that each clip assembly is required to both engage with the tail portion of a previous clip assembly and the trailing edge of a previous sheet, the cladding system ensures that the clip assembly is being laid correctly. The system is structured such that it effectively re-aligns or re-sets the system each time a clip assembly is laid, thereby avoiding any accumulated build-up in tolerance error of the sheet across the roof.

Further, the system dictates the position of each clip assembly by virtue of the locating means and the endmost clip's engagement with the previously laid sheet, thereby minimising the prospects that the sheet will be incorrectly laid.

Preferably the cladding system uses a clip assembly as described above wherein the locating means includes a pair of apertures wherein, in installation, one of the pair of apertures aligns with the other of the pair of a subsequent clip.

Further, the strap may include a part extending from the first end which forms a downwardly facing channel and the tail portion includes an upwardly facing 9 i channel which forms at least part of the locating means and which is adapted to receive the downwardly facing channel of the strap of a like clip assembly.

.o Preferably, on engagement of the first sheet of the endmost clip, at least too part of the endmost clip is exposed to allow for engagement of the leading edge portion of the second sheet to the endmost clip. In a preferred form, the endmost clip includes a pair of downwardly facing surfaces, and the clip is adapted for partial insertion under the trailing edge of the first sheet when laid such that an endmost one of the downwardly facing surfaces engages the first sheet with the other downwardly facing surface of the endmost clip being free for engagement 30 with the leading edge of the second cladding sheet. In this way, the overlapping 'i pa5217-98 specidoc:l/7100 edge regions between the first and second sheets can be secured to the underlying structure through the direct engagement with the endmost clip.

In a preferred form, the trailing edge portion of the cladding sheet includes an upwardly facing shoulder and a distal edge having a downwardly turned lip. In this arrangement, when the endmost clip is inserted under the trailing edge of the first sheet, the endmost one of the downwardly facing surfaces locates in a retained position above the upwardly facing shoulder of the trailing edge region and the endmost clip includes means for engaging the lip so as to retain the trailing edge in the retained position.

In a third aspect, the present invention relates to a method of fixing a plurality of cladding sheets to an underlying structure, the cladding sheet having at least one longitudinal extending rib and including longitudinal extending male and female edge regions, the female edge region being in the form of a rib part, the or each rib and rib part including an interior space bounded by opposing interior walls, the cladding sheet being fixed to the underlying structure by a plurality of clip assemblies, each clip assembly including a plurality of clips, and a strap, the strap extending along an axis and having a leading and trailing edge spaced along the axis, the clip assembly including an endmost clip located at or adjacent the leading edge of the strap, and the other clip or clips being located intermediate the leading 2"O and trailing edge such that the strap forms a tail portion which extends beyond the S other clip or clips to said trailing edge; the method including the steps of: fixing a first cladding sheet to the underlying structure, the cladding sheet being fixed by a first clip assembly fastened to the underlying structure, with the endmost clip of the first clip assembly engaging the rib part of the female edge region and the other clip or clips engaging the rib or ribs of the sheet; bringing a second clip assembly into engagement with the first clip assembly and the first cladding sheet, so that the second clip assembly engages the tail portion of the first clip assembly and the endmost clip of the second clip assembly engages the male edge region of the first cladding sheet; :.*eo pa52817-98 speci.doc:1/7/00 fastening the second clip assembly to the underlying structure whilst the second clip assembly is in engagement with both the first clip assembly and the first cladding sheet; and fixing a second cladding sheet to the underlying structure by locating the female edge region of the second cladding sheet over the endmost clip of the second clip assembly and the male edge region of the first cladding sheet and locating the rib or ribs of the second cladding sheet over the other clip or clips of the second clip assembly.

Preferably the first and second clip assemblies are guided into alignment on engagement of the second clip assembly with the tail portion of the first clip assembly.

BRIEF DESCRIPTION OF THE DRAWINGS Further preferred embodiments of the invention will now be described with reference to the accompanying drawings, in which: Fig. 1 is a schematic perspective showing installation of a roofing sheet using a prior art clip; Fig. 2 is a plan view of a preferred clip assembly in accordance with the present invention; Fig. 3 is a side view of the clip assembly of Fig. 2; "'20 Fig. 4 is a perspective view of the clip assembly of Fig. 2; Fig. 5A is a left hand end view of the clip assembly of Fig. 2; %00. Fig. 5B is a right hand end view of the clip assembly of Fig. 2; Fig. 6 illustrates the cladding sheet profile for use with the clip assembly of Fig. 2; Figs. 7A to 7D are schematic side views illustrating the installation procedure; and 8 is a detailed side view of a retaining formation of a clip engaged with the leading edge rib of a sheet and the trailing edge portion of the previous sheet.

S DETAILED DESCRIPTION OF THE DRAWINGS 30 With reference to Fig. 1, the prior art fixing system includes a clip consisting of a flat strap which has been folded along lines 900 to its length to form pa5281 7 98 speci.doc:1/7100 hump shaped retaining formations 11 a, 11 b at its ends. These formations have detents 12 therein to engage inside the female 13b and intermediate 14 ribs of the roofing sheets 15a, 15b. In use, the first hump 11 a of the clip is positioned over the male rib 16a on the trailing edge of the previously laid sheet 15a, and the clip is fixed to purlin 17 by screws at positions 18a and 19b. The second sheet 15b is then positioned with its female 13 band intermediate 14b ribs over the respective formations 11 a, 11 b and is pressed downwards to snap home over the detents 12 and to engage the female rib over the full length of the male rib 16a. The procedure is repeated for subsequent sheets, with the male rib of the final sheet being held by a finishing clip.

Figs. 2 to 5 illustrate the clip assembly. The clip assembly 20 includes a strap 21, the strap being elongate and having a leading and trailing end (22, 23 respectively). The strap 21 is shaped for most of its length as a shallow, downwardly facing channel 24 (as best shown in Fig. 5A). In the region of the trailing end 23, the channel inverts to form an upwardly facing channel 25 (best shown in Figs. 4 and 5B). The strap is arranged to be engaged and aligned in end to end configuration with a like strap and the channel 25 is configured to enable the leading end 22 of a like strap 21 to be received therein to facilitate alignment of the straps 21.

0,20 Three clips 26 are attached to the strap21 at predetermined intervals.

~These positions are arranged to correspond to distance between the leading edge rib 51 and to intermediate ribs 52 of the roofing sheet 50 of Fig. 6. Typically the clips 26 are riveted to the strap. However, any other suitable fixing arrangement may be used to locate the clips on the strap 21. As will become apparent later, it is 25 not necessary to secure the clips to the strap as this is achieved on fixing of the clip assembly 20 to the roof structure. Consequently, the fixing means for securing the clips to the strap is only required to withstand the loading expected during transportation and installation.

9o9l In the illustrated arrangement, each clip 26 is formed as a generally channel 30 shaped element 27 in the end view and comprises a base 28 and opposed upstanding retaining elements 29. The retaining elements are formed from sheet pa52817- 98 specl.doc:l/00OO material, preferably sheet metal, with each retaining element having a profile generally similar to the profile of the ribs in the rib sheet 50. Each retaining element includes a body portion 30 and a pair of opposed fixing portions 31 which are spaced from the base. The body portion 30 extends across the base and upwardly therefrom and the fixing portion extends from the body portion from an upstanding transition region 32.

Each fixing portion 31 includes first and second planar generally upstanding portions 33 and 34 respectively. The first portion 33 extends outwardly from the transition region 32 and the second portion 34 extends transversely to the first portion. In this way, a pair of downwardly facing shoulders or edge surfaces 43 are formed which are adapted for engagement with the re-entrant portions 53 of the respective ribs of the roof sheet 50. The second planar portion takes the form of an inwardly angled longitudinal flange which incorporates a pair of outwardly facing abutment surfaces 35. The outwardly facing abutment surfaces are arranged to engage the interior surface 54 of the respective ribs. A crown tab 56 in the form of an inwardly turned longitudinal top flange extends from an upper end 37 to the body portion 30 and forms the upper surface of the retaining element 29. There preferably is some clearance of the upper surface of the retaining element and the top of the interior 55 of the rib to allow the rib to flex while being snap-fitted onto "*20 the clip. Further, an upper edge 38 of the respective fixing portions 31 are spaced from the crown tab 36 to thereby form respective recesses 39 at the upper end 37 of the retaining element 29.

S* The base 28 includes a fixing location 40. In the illustrated arrangement, the fixing location is in the form of an aperture through which a fastening screw 41 25 is adapted to be received. As best seen in Fig. 2, the retaining elements 29 are located on opposing sides of the fixing location 40 and are disposed such that the fixing portions 31 of these elements are substantially symmetrical about the fixing location 40. Further, a space 42 is provided between the retaining elements 29 to enable access to the fastening screw 41 to effect fixing of the clip.

:'0o 30 Fig. 6 illustrates the profile of the cladding sheet 50. In the illustrated arrangement, the sheet 50 is generally planar and has two intermediate ribs 52.

pa52817-98 spec.doc:7/OO Each rib includes an interior space 54, which is bounded by opposing walls 56 and 57 interconnected by a bridging or apical portion 58. Each wall includes a re-entrant portion 53 to form opposingly upwardly facing abutment surfaces 59.

Furthermore, each sheet 50 includes a male 60 and female 61 longitudinal edge region. the sheet 50 is arranged to be juxtaposed with a like cladding sheet with the female edge region of one sheet overlapping the male edge region of the other sheet. In this way, a longitudinal rib is formed at the overlapping edge region.

The male edge region is upstanding from the plane of the sheet and forms a first rib part 62. The first rib part includes a side portion having a re-entrant zone 63 to provide offset upper and lower side walls 64, 65 interconnected by an intermediate wall 66. The intermediate wall has opposing upwardly and downwardly facing bearing surfaces 67, 68 and the upper side wall 64 extends from the intermediate wall 66 to a hooked terminal edge 69 of the cladding sheet 50. The female edge region 61 is also upstanding from the plane of the cladding sheet to form a second rib part 70. The second rib part has opposed first and second side portions 71, 72 interconnected by an apical portion 73. The first side portion extends from the sheet to the apical portion and includes a re-entrant zone 74 to provide offset upper and lower side walls 75, 76 interconnected by an intermediate wall 77. The intermediate wall 77 has opposing upwardly and oo** downwardly facing bearing surfaces 78, 79. The second side portion 72 extends :o downwardly from the apical portion 73 to the other terminal end 80. The second side portion 72 includes a re-entrant zone 81 to form offset upper and lower side S walls 82, 83 interconnected by an intermediate wall 84 having upwardly and 25 downwardly facing bearing surfaces 85, 86.

As illustrated in Figs. 7A to 7D, the first clip assembly 20a is secured to the purlin 87 by fasteners 41 passing through the fastener holes 40 in the strap between the retaining elements of each clip. Securing the clip assembly also compresses the insulation blanket 88.

30 As shown in Fig. 7B, the roofing sheet50a is aligned above the clip assembly 20a and pushed downwardly to snap fit the top portions of the ribs over 2 8 1 7 9 8 specl.doc:1/7/00 corresponding fixing portions of the retaining elements. Engagement between downwardly facing surfaces 43 of the retaining elements and opposed re-entrant parts 59 of each rib then prevent the sheet from being lifted out of engagement.

The outer surfaces 35 of the fixing portions above the surfaces 59 fit tightly inside upwardly convergent top walls 56, 57 of the rib to prevent twisting of the retaining elements.

The next clip assembly 20b is installed with the upper edge 38 of the endmost fixing portion 31 hooking under the lip 69 of the trailing edge portion 69 of the previously laid roofing sheet 50a such that the terminal end is held within the recess 39. The clip assembly20b is pivoted downwardly and brought into alignment with the assembly 20a so that the fastener holes 40 in the end 23 of the assembly 20a is aligned with the fastener hole 40 in the endmost clip 26 of the assembly 20b. The alignment of the circular fastener holes ensures exact positioning of the clip for correct roof pitching. The clip assemblies 20a and are secured to the purlin 87 by fasteners 41 passing through the aligned fastener holes 40 (Fig. 7C).

The next roofing sheet 50 is then aligned above clip assembly 20b and snapped home as described above for roofing sheet 50a, except that the leading female edge rib part 70 snaps over both the endmost clip 26 and the male trailing 20 end rib part 62 of the previous sheet. The engagement between the two clip assemblies 20a and 20b and the two sheets 50a and 50b is described below with t:= reference to Fig. 8.

As mentioned above, initially the male edge region having the hooked edge is received within the recess 39 of the leading end clip of the next clip assembly 20b. Once in this position, the side portion of the first rib part of the sheet 50 is engaged with the adjacent fixing portion of the clip such that the upwardly facing bearing surface is located against the downwardly facing abutment surface of the fixing portion of the respective retaining elements and the male edge region is retained in this position by this combined engagement.

30 Subsequently, the clip assembly 20b is pivoted downwards into position.

The clip assembly 20b is correctly positioned relative to the clip assembly 20a by pa5281 7 98 specidoc:ll7/00 its engagement with the tail portion of the previously laid assembly 20a through its nesting within the channel 25 and alignment of the circular fastener holes Because the male edge region is located at one edge of the retaining element, the space 42 provided to enable access for the fastening screw is not covered and therefore the clip 26 at the leading end can be fastened to the purlin 87 through the aligned apertures.

With this arrangement, on securing the clip assembly 20b in place, the clip assembly 20b is located correctly relative to the clip assembly 20a. Further, the trailing end 60 of the sheet 50 is also located in correct position relative to the clip assembly 20b by virtue of the engagement of the endmost clip 26 with the male trailing end rib part 62. As a result of this, the clip assembly 20b is correctly positioned in relation to the whole previously laid system with the clip assembly 20b ready to receive the next sheet 50 with each of the clips, including the inner side of the endmost clip exposed for engagement with the ribs of the sheet. This has the particular advantage that it avoids any accumulated tolerance error building up in the roofing system over the entire roof. Each time a clip assembly 20 is laid, this tolerance error is taken up by virtue of the dual engagement of the clip assembly both with the previously laid sheet and the previous clip assembly and is not carried over onto the next sheet.

Once the clip assembly 20b is fastened to the purlin, the next sheet is positioned with the rib part of the female edge end region overlapped with the male end region of the preceding sheet. The female region 61 is then snapped home with the outer surface of the side portion of the male edge region interlocking with the inner surface of the second side portion of the female edge region. In particular, the upwardly facing bearing surface of the second rib part engages the downwardly facing bearing surface of the side portion of the first rib part.

Furthermore, on the opposing side of the retaining elements the upwardly facing bearing surface of the first side portion of the female edge region is arranged to S engage the downwardly facing abutment surface of the fixing portion of the clip.

The illustrated clips and the manner of connection with the projecting edge portion of the sheet allow fasteners to be positioned centrally below the longitudinal pa52817-98 specd.doc:l7I00 rib of the roofing sheet for greater wind uplift resistance and allows direct engagement between the fixing portions and the leading edge rib. Furthermore, the short trailing edge portion allows greater material efficiency in the roofing sheet compared to the prior art.

The alignment of the retaining elements across the rib profile results in the fold line 44 between the retaining elements and the base 28 of the retaining member being parallel to the clip length, rather than perpendicular as in the prior art. Furthermore, the angled flanges 34 of the fixing portion are closely received in the top portion of the rib, restraining against bending of the clip in both the parallel or perpendicular directions. Consequently, the wind uplift forces acting through the flanges 34 act substantially parallel to the plane of the restraining element.

Extreme uplift forces attempt to twist the clip. This mechanism results in considerably greater resistance to wind uplift forces than the prior art hump-shaped retaining formation, in which the uplift forces attempt to unfold the hump by bending along the existing perpendicular fold lines.

As the retaining elements substantially correspond to the rib profile, separate bird proofing accessories are not required.

Unlike prior art clips, the tail 25 of the clip assembly extends past the final Sclip, thus supporting the full sheet profile and compressing the insulation blanket 88 in the region of connection of the laid sheet with the next clip. Further, as go0@ discussed above, this arrangement also allows the head of the next clip to nest Go .o within the channel section 25 at the tail of the previous clip, and the alignment of the circular fastener holes 40 ensures exact positioning of the clips for correct roof pitching.

While particular embodiments of the invention have been described, it will be evidence to those skilled in the art that the present invention may be embodied in other specific forms without departing from the essential characteristics thereof.

0 S The present embodiments and examples are therefore to be considered in all S. respects as illustrative and not restrictive, the scope of the invention being 30 indicated by the appended claims rather than the foregoing description, and all pa52817-98 speci.doo:l117100 changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

000 @0 0 00 P a21-8 pddcRS 0 e 1* 4

Claims (31)

1. A clip assembly for use in the concealed fixing of a series of successively laid cladding sheets, said, series including three successively laid sheets (hereinafter referred to respectively as the first, second and third laid sheet), said first, second and third laid sheets being of the type having a trailing edge portion,. one or more intermediate ribs and a leading edgpepotion adapted for engagement with the trailing edge portion of a previously laid sheet, the clip assembly including a strap and a plurality of clips, said strap being elongate and including spaced apart first and second ends, an endmost one of said clips being adjacent said first end, and said other clips being located intermediate said first and second ends such that said strap forms a tail portion which extends beyond said other clips to said second end, said endmost clip being adapted for engagement with both the trailihg edge portion of said first sheet and the leading edge portion of the second sheet, and said other clips being adapted for engagement with respective intermediate ribs of the second sheet, said tail portion being configured to underlie •:.000 the ,region of engagement between the trailing edge portion of said second sheet and the leading edge portion of the third sheet, said clip assembly further including S: locating means enabling the tail portion of the clip assembly to locate the first end S: of a subsequent clip assembly relative to the tail portion to provide correct positioning of said subsequent clip assembly relative to said clip assembly.

2. A clip assembly according to claim 1, wherein the locating means includes a t. ll pair of apertures, one being disposed adjacent the first end, the other being disposed in the tail portion, wherein in installation of the assemblies, the first end of the subsequent clip assembly overlaps with the tail portion of the clip assembly and 25 the aperture in the tail portion aligns with the aperture'adjacent the first end of the strap of the subsequent clip assembly.

3. A clip assembly according to claim 2, wherein the pair of apertures are of similar dimensicfris in the direction of the strap to correctly position the assemblies on alignment of the apertures.

4. A clip assembly according to claim 2 or 3, wherein the aligned apertures are designed to receive a fastener to secure the assemblies together.

A clip assembly according to any one of claims 2 to 4, wherein each clip includes a generally planar base and a retaining formation which upstands from the base, each of the clips being fastened to the strap by connection between its respective base and the strap, and the clip assembly further includes apertures which extend through respective ones of said bases and the strap which underlies said respective clips, with each aperture being configured to receive a fastener which is engagable with its associated base to secure said clip assembly to said underlying structure.

6. A clip assembly according to claim 5, wherein the aperture in the endmost clip forms one of the pair of apertures of the locating means.

7. A clip assembly according to either claim 5 or 6, wherein the clips are tack mounted to said strap, and are arranged to be secured to said strap by said fasteners.

8. A clip assembly according to any preceding claim, wherein said strap includes a part extending from said first end formed as a downwardly facing channel and said tail portion includes an upwardly facing channel which forms at least part of said locating means and which is adapted to receive the downwardly facing channel of the strap of a like clip assembly.

9. A clip assembly according to any preceding claim, wherein at least part of 20 the endmost clip is exposed on securing the trailing edge portion of the first sheet to said endmost clip to allow for engagement of the leading edge portion of the second sheet to said endmost clip.

10. A clip assembly according to claim 9, wherein said endmost clip includes a •5S55 pair of downwardly facing surfaces, said clip being adapted for partial insertion 25 under the trailing edge of said first sheet such that an endmost one of said downwardly facing surfaces engages the first sheet, with the other downwardly facing surface of the endmost clip being free for engagement with the leading edge of the second cladding sheet.

11. A concealed fix cladding system including cladding sheets of the type having spaced apart leading and trailing longitudinal edge portions and one or more ribs located intermediate the edge portions and extending along the sheet in pa52817-98 spec.doa:116/00 the longitudinal direction, the cladding sheets being arranged to be laid in three successively laid series (hereinafter referred to respectively as the first, second the third laid sheets) with the leading edge portion of a said sheet being arranged to be juxtaposed to overlap with the trailing edge portion of a previously laid sheet to form a longitudinal rib at said overlapping edge region, and a clip assembly, the clip assembly including a strap and a plurality of clips, said strap being elongate and extending between spaced apart first and second ends, an endmost one of said clips being at or adjacent said first end and the or each of the other of said clips being located intermediate said first and second ends such that said strap forms a tail portion which extends beyond said other clips to said second end, wherein in use, the strap is secured to an underlying structure and the clips are arranged to engage with associated ones of said cladding sheets so as to fix the cladding sheets to the underlying structure with said endmost clip engaging both the trailing edge portion of said first sheet and the leading edge portion of the S15 second sheet, and the other clips engaging with a respective one of the intermediate ribs of the second sheet, the tail portion being configured to underlie *the region of engagement between the trailing edge portion of the second sheet and the leading edge portion of the third sheet, and wherein the clip assembly I* further includes locating means enabling the tail portion of the clip assembly to locate the first end of a subsequent clip assembly relative to the tail portion in a predetermined position after securing of said second sheet, such that in installation of the system, the subsequent clip assembly is correctly positioned relative to the second sheet and the clip assembly by operation of the locating means and through engagement of the endmost clip of the subsequent clip assembly with the 25 trailing edge portion of said second sheet.

12. A cladding system according to claim 11, wherein the locating means includes a pair of apertures, one being disposed adjacent the first end, the other being disposed in the tail portion, wherein in installation of the system, the first end of the subsequent clip assembly overlaps with the tail portion of the clip assembly with the aperture in the tail portion aligning with the aperture adjacent the first end of the strap of the subsequent clip assembly. Spa52817-98

13. A cladding system according to claim 12, wherein the pair of apertures are of similar dimensions in the direction of the strap to correctly position the assemblies on alignment of the apertures.

14. A cladding system according to either claim 12 or 13, wherein the aligned apertures are designed to receive a fastener to secure the assemblies together.

A cladding system according to any one of claims 12 to 14, wherein each clip includes a generally planar base and a retaining formation which upstands from the base, each of the clips being fastened to the strap by connection between its respective base and the strap, and the clip assembly further includes apertures which extend through respective ones of the bases and the strap which underlies said respective clips, with each aperture being configured to receive a fastener which is engagable with its associated base to secure said clip assembly to said underlying structure.

16. A cladding system according to claim 15, wherein when the first sheet is in V, 15 engagement with the endmost clip, its trailing edge portion is spaced from the aperture in the endmost clip to enable access for a fastener to be located through said aperture to secure said clip assembly to said underlying structure.

17. A cladding system according to either claim 15 or 16, wherein the aperture in the endmost clip forms one of the pair of apertures of the locating means. 20

18. A cladding system according to any one of claims 15 to 17, wherein the clips are tack mounted to said strap, and are arranged to be secured to said strap by said fasteners.

19. A cladding system according to any one of claims 11 to 18, wherein said strap includes a part extending from said first end formed as a downwardly facing 25 channel and said tail portion includes an upwardly facing channel which forms at least part of said locating means and which is adapted to receive said downwardly facing channel of the strap of a like clip assembly.

A cladding system according to any one of claims 11 to 19, wherein on engagement of the first sheet with the endmost clip, at least part of the endmost clip is exposed to allow for engagement of the leading edge portion of the second sheet to said endmost clip. pa52817-98 spec.doc:16100

21. A cladding system according to claim 20, wherein said endmost clip includes a pair of downwardly facing surfaces, said clip being adapted for partial insertion under the trailing edge of said first sheet when laid such that an endmost one of said downwardly facing surfaces engages the first sheet with the other downwardly facing surface of the endmost clip being free for engagement with the leading edge of the second cladding sheet so as to enable the overlapping edge regions between the first and second sheets to be secured to the underlying structure by said endmost clip.

22. A cladding system according to claim 21, wherein the trailing edge portion of said cladding sheet includes an upwardly facing shoulder and a distal edge having a downwardly turned lip, and when said endmost clip is inserted under said trailing edge of said first sheet, the endmost one of said downwardly facing surfaces locates in a retained position above the upwardly facing shoulder of said trailing edge region, said endmost clip including means for engaging said lip so as to retain said trailing edge region in said retained position.

23. A cladding system according to claim 21, wherein the leading edge portion of said cladding sheet includes a rib part having a pair of opposed re-entrant portions, and wherein said rib part of said second sheet overlaps with the trailing *i end region of said first sheet in said retained position with one of said re-entrant portions locating under said shoulder of the trailing edge region of the first sheet and the other re-entrant portion engages said free downwardly facing surface of said endmost clip.

24. A cladding system according to claim 23, wherein the leading edge rib part of said second sheet overlaps in a snap fit engagement with the endmost clip and 25 said trailing edge region of said first sheet in said retained position.

25. A method of fixing a plurality of cladding sheets to an underlying structure, the cladding sheet having at least one longitudinal extending rib and including longitudinal extending male and female edge regions, the female edge region being in the form of a rib part, the or each rib and rib part including an interior space bounded by opposing interior walls, the cladding sheet being fixed to the underlying structure by a plurality of clip assemblies, each clip assembly including pa52817-98 spec.doc:ll/600 a plurality of clips, and a strap, the strap being elongate and extending between spaced apart first and second ends, said clip assembly including an endmost clip located at or adjacent the first end of said strap, and the other clip or clips being located intermediate the first and second ends such that said strap forms a tail portion which extends beyond said other clips to said second end; the method including the steps of: fixing a first cladding sheet to the underlying structure, the cladding sheet being fixed by a first clip assembly fastened to said underlying structure, with the endmost clip of the first clip assembly engaging the rib part of the female edge region and the other clip or clips engaging the rib or ribs of said sheet; bringing a second clip assembly into engagement with the first clip assembly and the first cladding sheet, so that the second clip assembly engages the tail portion of the first clip assembly and the endmost clip of the second clip assembly engages the male edge region of the first cladding sheet; fastening said second clip assembly to the underlying structure whilst o the second clip assembly is in engagement with both the first clip assembly and the first cladding sheet; and fixing a second cladding sheet to the underlying structure by locating "the female edge region of the second cladding sheet over the endmost clip of the second clip assembly and the male edge region of the first cladding sheet and o locating the rib or ribs of the second cladding sheet over the other clip or clips of the second clip assembly.

26. A method according to claim25, wherein the first and second clip do to.. assemblies are guided into alignment on engagement of the second clip assembly with the tail portion of the first clip assembly.

27. A method according to claim 25 or 26, wherein the second clip assembly overlaps with the tail portion of the first clip assembly and wherein, when fastening said clip assembly to said underlying structure, a fastener is located through said overlap between the tail portion and the second clip assembly.

28. A method according to claim 27, wherein the clip assemblies each include an aperture both in the tail portion and adjacent to the first end and wherein on pa52817-98 speci.doc:1/6/00 aligning the first end of the second clip assembly with the tail portion of the first clip assembly, the aperture adjacent the leading edge in the second clip assembly aligns with the aperture in the tail portion of the first clip assembly.

29. A method according to claim 28, wherein a fastener is secured to the underlying structure through said aligned apertures.

A method according to any one of claims 25 to 29, wherein in fastening said clip assemblies to said underlying structure, fasteners are secured to said underlying structure through said respective clips.

31. A cladding system when concealed fixed to an underlying structure by a method according to any one of claims 25 to DATED: 20 January 2000 PHILLIPS ORMONDE FITZPATRICK Attorneys for STRAMIT CORPORATION LIMITED 4 4 9