AU2016206190A1

AU2016206190A1 - Roof clip

Info

Publication number: AU2016206190A1
Application number: AU2016206190A
Authority: AU
Inventors: Michael Celeban; Rodney John Gallaty
Original assignee: BlueScope Steel Ltd
Current assignee: BlueScope Steel Ltd
Priority date: 2015-01-07
Filing date: 2016-01-07
Publication date: 2017-07-13
Anticipated expiration: 2036-01-07
Also published as: AU2016206190B9; AU2021201732B2; AU2016206190B2; AU2023201975A1; AU2021201732A1; WO2016109871A1

Abstract

A two-part interlocking clip allows movement of the parts of the clip relative to each other and is adapted to secure a cladding sheet, such as a roof cladding sheet, such as a "pierce-fixed" or a closed-rib roof cladding sheet, on a support structure.

Description

PCT/AU2016/050004 WO 2016/109871

ROOF CLIP TECHNICAL FIELD 5 The present invention relates to a two-part interlocking clip that allows movement of the parts of the clip relative to each other.

The present invention relates particularly, although by no means exclusively, to a clip for securing a cladding sheet, such as a roof cladding sheet, on a support structure that allows relative movement of parts of the clip in a way that can accommodate 10 movement of the cladding sheet in a longitudinal direction of the sheet relative to the support structure.

The relative movement may be relative movement during installation of the cladding sheet on the support structure.

By way of further example, the movement may be relative movement due to 15 thermal expansion and contraction of the cladding sheet after installation of the cladding sheet on the support structure.

The present invention also relates particularly, although by no means exclusively, to a clip for securing two longitudinally aligned cladding sheets, such as two longitudinally aligned roof cladding sheets, on a support structure at an overlap of 2 0 the ends of the cladding sheets that allows relative movement of parts of the clip in a way that can accommodate relative movement of the cladding sheets in a longitudinal direction of the sheets. The relative movement may be relative movement during installation of the cladding sheets in end to end relationship. By way of further example, the relative movement may be relative movement due to thermal expansion 25 and contraction of the cladding sheets after installation of the cladding sheets.

The present invention relates more particularly, although by no means exclusively, to a roof or other structure that includes a support structure, a plurality of cladding sheets secured on the support structure, and at least one clip that secures a cladding sheet on the support structure or two longitudinally aligned cladding sheets at 30 an overlap of the ends of the cladding sheets on the support structure that allows relative movement of parts of the clip in a way that accommodates relative movement 1 PCT/AU2016/050004 WO 2016/109871 of the cladding sheet and the support structure in a longitudinal direction of the sheet or relative movement of the two cladding sheets in a longitudinal direction of the sheets.

The invention is particularly concerned with a clip that is adapted to secure roof cladding sheets to roof support structures and the following description focuses on this 5 use of the clip of the invention.

However, the clip of the invention is not limited to use with roof cladding sheets and can be used in other applications, such as with cladding sheets for walls and fences.

BACKGROUND ART 10

The term “clip assembly” as used herein is understood to mean a clip and fasteners, such as nails and screws, for securing the clip to an underlying structure.

The term “cladding sheet” is understood herein to mean a profiled metal sheet, typically roll-formed or pressed, that includes one or more parallel ribs with opposed 15 sides, pan sections, and side edge formations that enable a plurality of the sheets to be positioned in side by side overlapping relationship. The structure of the sheet is such that a plurality of the sheets can be positioned in end-to-end overlapping relationship. The ribs may be open ribs or closed ribs.

Cladding sheets may be roll-formed or pressed from painted or unpainted steel 2 o strip or formed from extruded aluminium or plastics material.

As is indicated above, the invention is particularly concerned with securing roof cladding sheets to roof support structures.

The installation of roof cladding sheets to form a roof involves the placement of sheets in side by side overlapping relationship across a section of the roof and in end to 2 5 end relationship along the length of the roof in situations where roof cladding sheets are not sufficiently long and wide to cover a required roof area.

It is known to secure roof cladding sheets to an underlying support structure, such as roof purlins, by fastening the sheets directly to the underlying structure using fasteners, such as roofing nails and screws, which pierce the sheets and penetrate the 3 o underlying structure. These sheets are commonly referred to as “pierce-fixed” roof cladding sheets. Typically, the ribs of “pierce-fixed” roof cladding sheets are open ribs, 2 PCT/AU2016/050004 WO 2016/109871 i.e. with side walls that diverge outwardly and downwardly from opposite side edges of a top wall of the rib.

The invention has particular, although not exclusive, application for “pierce-fixed” roof cladding sheets. 5 One known “pierce-fixed” roof cladding sheet having open ribs is marketed under the Registered Trade Mark “Trimdek” by the applicant. It is noted that the invention is not confined to the Trimdek roof cladding sheet.

It is also known to secure cladding sheets having closed ribs to an underlying structure by using clips that are secured to the structure by fasteners and are formed to 10 extend into the ribs and include retaining members or tabs that can engage re-entrant portions of the closed ribs and thereby retain the sheets to the clips. These clip assemblies are often preferred over nails and other fasteners because they enable concealed fixing of cladding sheets to an underlying structure.

In use, the concealed fixing retaining clips are secured to an underlying structure 15 at spaced intervals related to the spacing between the ribs of the cladding sheets.

Thereafter, cladding sheets are positioned on the clips in overlapping relationship by successively pressing the sheets down onto the clips so that the sides of the ribs are initially forced outwardly to allow the re-entrant portions of the ribs to pass over the retaining members and then snap inwardly into engagement with the retaining 2 o members.

The invention also is applicable for use with cladding sheets having closed ribs.

One known roof cladding sheet having closed ribs that is suitable for use with concealed fixing retaining clips is marketed under the Registered Trade Mark “Lysaght Klip-Lok” by the applicant. It is noted that the invention is not confined to use with the 2 5 Lysaght Klip-Lok roof cladding sheet.

It is noted that the clip of the invention is not confined to any particular type of roof cladding sheet.

The following description of the invention focuses on the use of the invention in relation to “pierce-fixed” roof cladding sheets such as the Trimdek roof cladding sheet. 3 o However, it is emphasized that the invention is not confined to use with this type of roof cladding sheet. 3 PCT/AU2016/050004 WO 2016/109871

The Trimdek roof cladding sheet is a popular roofing profile used in commercial and industrial roofing applications in Australia and has become commoditized. It is popular due to the production economics and suitability for long roof runs.

However, screw-fixing of the Trimdek and other “pierce-fixed” roof cladding 5 sheets to a support structure at spaced locations along the lengths of the sheets prevents thermal expansion and contraction of the sheets in a longitudinal direction and, as a consequence, there is a restriction on the maximum sheet length before end to end overlapping of sheets, with an expansion/contraction joint at the overlaps, is required to accommodate thermal expansion and contraction of the sheets. Restricting the 10 maximum length of “pierce-fixed” roof cladding sheets can be inefficient in terms of production and installation costs. In addition, known step/expansion joints are a costly construction detail and are subject to poor construction practices.

The above-described thermal expansion and contraction issue with the Trimdek and other “pierce-fixed” roof cladding sheets also applies to the Lysaght Klip-Lok and 15 other closed-rib roof cladding sheets and other types of roof cladding sheets that are retained to support structures by concealed fixing retaining clips.

The above references to the background art do not constitute an admission that the art forms a part of the common general knowledge of a person of ordinary skill in the art. The above references to the background art are also not intended to limit the 2 o application of the clip of the invention and the separate parts of the clip as disclosed herein.

SUMMARY OF THE DISCLOSURE 25 In broad terms, the present invention provides a two-part interlocking clip that allows movement of the parts of the clip relative to each other and is adapted to secure a cladding sheet, such as a roof cladding sheet, such as a “pierce-fixed” or a closed-rib roof cladding sheet, on a support structure.

In broad terms, the present invention provides a clip for securing a cladding 30 sheet, such as a roof cladding sheet, such as a “pierce-fixed” or a closed-rib roof cladding sheet, on a support structure, with the clip including a first part adapted to be fastened to the support structure and a second part adapted to have the cladding sheet 4 PCT/AU2016/050004 WO 2016/109871 secured to it, with the first part and the second part being adapted to interlock together in a way that allows relative movement of the parts, for example by being slidable relative to each other, that can accommodate relative movement of the cladding sheet and the support structure in a longitudinal direction of the sheet. 5 The applicant has found that the above-described relative movement that is possible with the clip of the invention facilitates installing roof cladding sheets (and other cladding sheets) on support structures.

The applicant has also found that the clip of the invention makes it possible to form an effective thermal expansion/contraction coupling of roof cladding sheets and 10 roof support structures (and other cladding sheets and support structures).

The first part and the second part of the clip may be adapted to interlock together in a way that allows the parts to be slidable with respect to each other. With this arrangement, the clip can accommodate movement of the cladding sheet relative to the support structure, such as during installation or due to thermal expansion and 15 contraction of the cladding sheet after installation, by relative sliding movement of the parts. With this arrangement, in use, the first part of the clip is secured to a support structure and the cladding sheet is secured to the second part of the clip and the parts can slide relative to each other in a longitudinal direction of the cladding sheet in response to relative movement such as during installation or thermal expansion and 2 o contraction after installation of the cladding sheet. The parts are formed to accommodate the sliding movement whilst still being operatively coupled together to retain the cladding sheet on the support structure.

It is noted that the invention is not confined to interlocking the first and the second parts together by forming the parts to be slidable with respect to each other, 2 5 although slidable movement is preferred, and extends to any type of interlock that can accommodate relative movement such as during installation or thermal expansion and contraction after installation of the cladding sheet in the longitudinal direction of the sheet with the parts of the clip still being operatively coupled together and retaining the cladding sheet on the support structure together. 30 The cladding sheet may be a profiled sheet with at least one pan and at least one upstanding rib.

The cladding sheet may be a roof cladding sheet. 5 PCT/AU2016/050004 WO 2016/109871

The roof cladding sheet may be a profiled sheet with at least one pan and at least one upstanding rib.

The profiled roof cladding sheet may include two pans separated by the upstanding rib. 5 The clip of the invention may be adapted for securing two longitudinally aligned “pierce-fixed” or closed-rib or other types of roof cladding sheets to the support structure at an overlap of the ends of the roof cladding sheets, with the roof cladding sheets being in end-to-end, i.e. end lap, overlapping relationship.

The first part of the clip may be adapted to be positioned on an upper surface of ίο a lower roof cladding sheet that is positioned on the support structure and to be fastened to the support structure and thereby clamp the lower cladding sheet to the support structure, and the second part of the clip may be adapted to have an upper roof cladding sheet secured to it, whereby the upper roof cladding sheet can move relative to the support structure and the lower cladding sheet in the longitudinal direction of the sheets 15 via relative movement of the parts of the clip.

The second part of the clip may be adapted to have the upper roof cladding sheet secured to it by means of a fastener extending through the upper roof cladding sheet into the second part of the clip.

The second part of the clip may be adapted to have the upper roof cladding sheet 2 o secured to it by engagement of the second part of the clip with internal parts of the ribs of upper roof cladding sheet.

With this arrangement, in use, the upper roof cladding sheet can move relative to the lower roof cladding sheet in response to relative movement such as during installation or thermal expansion or contraction after installation of the upper roof 25 cladding sheet by virtue of the interlock between the first and the second parts of the clip that allows relative movement of the parts, with the first part securing the lower roof cladding sheet to the support structure and the second part securing the upper roof cladding sheet to it, and with the parts of the clip still being operatively coupled together and holding the roof cladding sheets and the support structure together. 3 0 The clip may include an opening in the first part of the clip to allow a fastener to be inserted through the opening to secure (a) the first part of the clip to the support structure where there is a single roof cladding sheet only or (b) the first part of the clip 6 PCT/AU2016/050004 WO 2016/109871 and the lower roof cladding sheet to the support structure thereby clamping the lower cladding sheet to the support structure, where there are upper and lower roof cladding sheets in end-to-end, i.e. end lap, overlapping relationship.

The clip may include an opening in the second part of the clip to allow a 5 fastener to be inserted through the opening to fasten (a) the roof cladding sheet to the second part in a situation where there is a single roof cladding sheet only or (b) the upper roof cladding sheet to the second part in a situation where there are upper and lower roof cladding sheets in end-to-end, i.e. end lap, overlapping relationship.

The second part of the clip may include formations such as tabs or other 10 members that are adapted to engage internal parts of the ribs of (a) the roof cladding sheet in a situation where there is a single roof cladding sheet only or (b) the upper roof cladding sheet in a situation where there are upper and lower roof cladding sheets in end-to-end, i.e. end lap, overlapping relationship.

The first and the second parts of the clip may be formed so that the clip can 15 provide sufficient resistance to vertical separation and resultant uplift of roofing sheets during wind loading.

The first and the second parts of the clip may be formed so that the clip can provide sufficient downward support during installation of a roof and for foot traffic on the roof. The sufficient support may be a consequence of materials selection and/or the 2 o profile of one or both of the parts.

The first part of the clip may include a body portion in the form of a web and two flanges extending outwardly and optionally downwardly from opposite side edges of the web. The purpose of the flanges is to facilitate interlocking the first and the second parts together. 2 5 The first part of the clip may be formed so that, in use, the web contacts and is supported by a rib of a lower roof cladding sheet with the flanges of the first part extending outwardly and downwardly from the rib when the lower cladding sheet is a profiled sheet having at least two pans separated by a rib.

The web of the first part of the clip may include the above-described opening for 3 o the fastener to be inserted through the opening.

The second part of the clip may include a body portion in the form of a web and two flanges extending outwardly and downwardly from opposite side edges of the web 7 PCT/AU2016/050004 WO 2016/109871 and in-turned lips at the ends of the flanges, with the flanges and the in-turned lips of the second part defining parallel channels on opposite sides of the web that are adapted to receive outer end sections of the flanges of the first part and interlock the first and the second parts together so that the parts are slidable with respect to each other. 5 The web of the second part of the clip may include the above-described opening for the fastener to be inserted through the opening.

The first and second parts of the clip may be formed so that the second part can be interlocked with the first part by positioning the second part so that the channels are aligned longitudinally with the ends of the flanges of the first part and then moving the 10 second part towards the first part so that the channels slide along the end sections of the flanges of the first part and, in effect, position the end sections in the channels.

The clip may include an assembly for locking the first and second parts together. This is a useful feature to hold the parts together prior to and during installation of the clip on a roof. The locking assembly is formed so that the parts can move relative to 15 each other as required during installation and in response to thermal expansion and contraction of the roof cladding sheet(s).

The locking assembly may include locking elements on the first and second parts that are adapted to cooperate together to lock the parts together.

The locking assembly may include a notch or other suitable formation in the 2 o outer end section of each flange of the first part and a complementary projection extending inwardly into each channel of the second part. With this arrangement, in use, when the parts are positioned together with the projections extending into the notches, the notches provide resistance to sliding movement of the second part relative to the first part until an applied force on the parts (for example due to expansion/contraction 25 of the roofing sheet(s)) is such as to disengage the notches and the projections.

The web of the second part of the clip may include an opening that is aligned vertically with the opening in the web of the first part of the clip so that a fastener can be inserted through the aligned openings and secure (a) the first part to the support structure where there is a single cladding sheet only or (b) the first part of the clip and 30 the lower cladding sheet to the support structure where there are upper and lower cladding sheets in end-to-end, i.e. end lap, overlapping relationship, thereby clamping the lower cladding sheet to the support structure. 8 PCT/AU2016/050004 WO 2016/109871

The web of the second part of the clip may include two other flanges extending outwardly and downwardly from opposite side edges of the web for contacting the web of the first part of the clip and spacing the second part above the first part with a predetermined clearance of the second part above the first part. 5 The web of the first part of the clip may include two upwardly curved side walls on opposite side edges of the web to facilitate locating the two other flanges of the second part of the clip in relation to the first part.

The spacing between the two upwardly curved side walls of the first part of the clip may be greater than the spacing between the two other flanges of the second part of 10 the clip so that, in use, the two other flanges of the second part fit inside the two upwardly curved side walls of the first part and the two upwardly curved side walls prevent lateral movement of the second part with respect to the first part.

The web and the flanges of the second part of the clip may be formed so that a rib of the upper roof cladding sheet can fit snuggly over the web and the flanges when 15 the upper cladding sheet is a profiled sheet having at least two pans separated by a rib.

The first and the second parts of the clip may be formed to ensure that there is a sufficient clearance fit to prevent vertical separation of the parts during installation of the roof cladding sheet or sheets.

The clip may be sold in a pre-assembled arrangement of the first and the second 2 o parts.

The clip may be sold with the first and the second parts as separate parts that are assembled together on site.

The clip may be made from sheet steel or any other suitable material. For example, the clip may be made from aluminium or a plastics material. The steel may be 25 G300 or G550 steel.

The clip may be any suitable length and any suitable height.

The first part of the clip may be adapted to retain a weather strip in a selected position, for example on a lower cladding sheet.

The weather strip may be an elongate weather strip for at least partially filling a 30 space between the upper roof cladding sheet and the lower roof cladding sheets in a situation where there are two roof cladding sheets in end-to-end, i.e. end lap, overlapping relationship. 9 PCT/AU2016/050004 WO 2016/109871

The weather strip may be formed from a compressible material.

The weather strip may be any suitable weather strip and, by way of example only, may be as described in International application PCT/AU2013/001325 (WO/2014/075149) in the name of the applicant. The disclosure in International 5 application PCT/AU2013/001325 is incorporated herein by cross-reference.

The weather strip may include a pan section that in use is positioned in and fills a gap between overlapping pans of the upper and the lower cladding sheets, with the pan section including an upper surface having a series of troughs and ridges along the length of the pan section that provide the pan section with a variable height along the ίο length of the pan section, whereby in use the ridges of the pan section compress when the upper cladding sheet is positioned on and engaged with the lower cladding sheet in an overlapping relationship with the pan section at least partially filling the gap between the overlapping pans of the cladding sheets.

The upper surface may be a scalloped surface. 15 The upper surface of the pan section of the elongate weather strip makes it possible to use lower forces to position the upper cladding sheet, which typically has pans that have a flat under surface, onto the lower cladding sheet and nevertheless fill the gap between the overlapping pans of the cladding sheets than would be required if the pan section of the weather strip had a constant height. 2 0 It is noted that there may be situations where it is not necessary for the weather strip to completely fill the space between the upper cladding sheet and the lower cladding sheet.

More particularly, the present invention provides a clip for securing two longitudinally aligned roof cladding sheets, such as a “pierce-fixed” or a closed-rib 25 roof cladding sheet, to a support structure at an overlap of the ends of the cladding sheets, with the clip including a first part adapted to be positioned on an upper surface of a lower roof cladding sheet that is positioned on the support structure and to be fastened to the support structure and thereby clamp the lower cladding sheet to the support structure, and a second part adapted to have an upper roof cladding sheet 30 secured to it, with the first part and the second part being adapted to interlock together in a way that allows the parts to be slidable with respect to each other to allow the upper roof cladding sheet to move relative to the support structure and the lower cladding to PCT/AU2016/050004 WO 2016/109871 sheet in the longitudinal direction of the sheets via relative movement of the parts of the clip.

The present invention also provides a clip assembly that holds a cladding sheet, such as a roof cladding sheet, on a support structure, with the clip assembly including 5 the above-described clip and fasteners, with at least one fastener fastening the first part of the clip to the support structure, and with the first and the second parts of the clip being interlocked together in a way that allows relative movement of the parts that can accommodate relative movement, such as via sliding movement, of the cladding sheet and the support structure. The relative movement may be relative movement during 10 installation of the cladding sheet on the support structure or due to thermal expansion and contraction of the cladding sheet after installation.

The present invention also provides a clip assembly that holds together a first cladding sheet and a second cladding sheet in an end to end, i.e. end lap, relationship on a support structure with the second sheet overlapping the first sheet, and with the clip 15 assembly including the above-described clip and fasteners, with the first cladding sheet positioned on the support structure and at least one fastener fastening the first part of the clip and the first cladding sheet to the support structure, with the second cladding sheet secured to the second part of the clip, and with the first part and the second part of the clip being interlocked together in a way that allows relative movement of the parts 2 o that can accommodate relative movement of the cladding sheets. The relative movement may be relative movement during installation of the cladding sheets in end to end relationship or due to thermal expansion and contraction of the cladding sheets after installation.

The first and second cladding sheets described in the preceding paragraph may 25 be upper and lower roof cladding sheets, respectively,

The present invention also provides a structure, such as a roof, that includes a support structure, a plurality of cladding sheets, and a line of the above-described clips holding the cladding sheets on the support structure.

The present invention also provides a structure, such as a roof, that includes a 30 support structure, a plurality of first cladding sheets in side by side overlapping relationship, a plurality of second cladding sheets in side by side overlapping relationship, with the first and the second cladding sheets being in an end to end, i.e. 11 PCT/AU2016/050004 WO 2016/109871 end lap, relationship, a line of the above-described clips holding the first and the second cladding sheets on the support structure,

The present invention also provides a roof that includes a roof support structure, a plurality of roof cladding sheets in side by side and end-to-end overlapping 5 relationship, a line of the above-described clips holding the roof cladding sheets on the support structure, and a line of weather strips at least partially filling gaps between the cladding sheets and the roof support structure on one side of the line of clips.

The present invention also provides a roof that includes a roof support structure, a plurality of upper roof cladding sheets in side by side overlapping relationship, a 10 plurality of lower roof cladding sheets in side by side overlapping relationship, with the upper and the lower cladding sheets being in an end to end, i.e. end lap, relationship, a line of the above-described clips holding the upper and the lower roof cladding sheets on the support structure, and a line of the weather strips at least partially filling gaps between the upper and the lower cladding sheets on one side of the line of clips. 15 The roof may further include another line of the above-described weather strips at least partially filling gaps between the upper and the lower cladding sheets on the opposite side of the line of clips.

The construction of the weather strips and the position of the weather strips in relation to the clips may be selected to facilitate engagement of an upper cladding sheet 2 0 on the clip by acting as a cushion that prevents excessive downward force on the clip that could damage the clip and a lower cladding sheet or the upper cladding sheet when the upper cladding sheet is pushed down onto the clip.

The present invention also provides a method of installing a roof cladding sheet on a support structure of a roof using the above-described clip (i.e. with the two parts of 25 the clip assembled together) that includes the steps of: (a) fastening the first part of the above-described clip onto the underlying roof support structure; and (b) securing, for example by means of fasteners, the cladding sheet onto the second part of the clip. 30 The method may include positioning a weather strip on the support structure before step (b) of securing the cladding sheet onto the second part of the clip.

The weather strip may be the above described weather strip. 12 PCT/AU2016/050004 WO 2016/109871

The present invention also provides a method of installing a plurality of roof cladding sheets in end to end overlapping relationship on a support structure of a roof using the above-described clip (i.e. with the two parts of the clip assembled together) that includes the steps of: 5 (a) laying a plurality of lower cladding sheets onto an underlying roof support structure in side by side overlapping relationship; (b) positioning a plurality of the above-described clip on the lower cladding sheets and forming a line of clips across the width of the sheets; (c) fastening the clips to the lower cladding sheets and the underlying roof 10 support structure, thereby clamping the lower cladding sheet to the support structure; and (d) successively laying a plurality of upper cladding sheets in side by side overlapping relationship and in end to end overlapping relationship onto the second parts of the clips; and 15 (e) securing, for example by means of fasteners, each upper cladding sheet to the second parts of the clips.

The method may include positioning a plurality of weather strips across the upper section of the lower cladding sheets in a continuous line before step (b) of forming the line of clips across the width of the sheets. 2 o The method may include positioning another a plurality of weather strips across the upper section of the lower cladding sheets in another continuous line that is parallel to the existing line of weather strips before step (b) of forming the line of clips across the width of the sheets.

The weather strip may be the above described weather strip. 25 The roof cladding sheets may be profiled sheets with each sheet having at least two pans separated by an upstanding rib.

Step (b) of the method may include positioning the clips on the ribs of the lower cladding sheets.

The method may include turning up the upper ends of the pans of the lower 3 o cladding sheets before step (d) of laying the upper cladding sheets onto the second parts of the clips. 13 PCT/AU2016/050004 WO 2016/109871

The method may include turning down the lower ends of the pans of the upper cladding sheets before step (d) of laying the upper cladding sheets onto the second parts of the clips.

BRIEF DESCRIPTION OF THE DRAWINGS

Notwithstanding any other forms which may fall within the scope of the invention, specific embodiments of the invention will now be described, by way of 10 example only, with reference to the accompanying drawings of which:

Figures 1 to 3 are perspective views illustrating the two parts of a first embodiment of a clip in accordance with the invention and how the two parts are assembled together to form an assembled and operative clip and different steps in an embodiment of a method of installing two longitudinally aligned “pierce-fixed” profiled 15 roof cladding sheets in end to end overlapping relationship on a support structure of a roof using the first embodiment of the clip in accordance with the invention;

Figure 4 is a perspective view of the installed roof cladding sheets at the end of the embodiment of the installation method shown in Figures 1 to 3;

Figure 5 is a perspective view of the installed roof cladding sheets shown in 2 o Figure 4 in another direction;

Figures 6 to 9 are a series of perspective views illustrating further the sequence of steps shown in Figures 1 to 3 in the embodiment of the method of installing two longitudinally aligned “pierce-fixed” profiled roof cladding sheets in end to end overlapping relationship on a support structure of a roof using the first embodiment of 2 5 the clip in accordance with the invention;

Figure 10 is a vertical cross-section through installed roof cladding sheets shown in Figures 4 and 5 illustrating the assembly of the two parts of the first embodiment of the clip and the position of the clip in relation to the profiled roof cladding sheets; 30 Figure 11 is an exploded side view illustrating the positions of the first embodiment of the clip shown in Figures 1 to 3 and 6 to 9, the roof cladding sheets, and 14 PCT/AU2016/050004 WO 2016/109871 the weather strips prior to securing the assembly with fasteners to an underlying roof support structure;

Figure 12 is a perspective view of a slightly modified form of the assembled two-part clip of the invention shown in Figures 1 to 3 and 6 to 9; 5 Figures 13 to 17 are perspective, upper, end and side views of the first part of the embodiment of the two-part clip of the invention shown in Figures 1 to 3 and 6 to 9;

Figures 18 to 21 are upper, end and side views of the second part of the embodiment of the two-part clip of the invention shown in Figures 1 to 3 and 6 to 9;

Figure 22 is a transverse cross-section of two longitudinally aligned “pierce- 10 fixed” roof cladding sheets in end to end overlapping relationship that are secured to a support structure of a roof using a second embodiment of a two-part clip in accordance with the invention;

Figure 23 is a side view of the first part of the two-part clip of the embodiment shown in Figure 22; 15 Figure 24 is a side view of the second part of the two-part clip of the embodiment shown in Figure 22;

Figure 25 is a transverse cross-section of two longitudinally aligned “pierce-fixed” roof cladding sheets in end to end overlapping relationship that are secured to a support structure of a roof using a third, although not the only other possible, 2 o embodiment of a two-part clip in accordance with the invention;

Figure 26 is a side view of the first part of the two-part clip of the embodiment shown in Figure 17;

Figure 27 is a side view of the second part of the two-part clip of the embodiment shown in Figure 26; and 2 5 Figures 28 to 30 are upper, end and side views of the first part of a fourth, although not the only other, embodiment of the two-part clip of the invention.

DESCRIPTION OF EMBODIMENTS 3 o The invention is a two-part interlocking clip that allows movement of the parts of the clip relative to each other and is adapted to secure a cladding sheet, such as a roof 15 WO 2016/109871 PCT/AU2016/050004 5 10 15 20 25 cladding sheet, such as a “pierce-fixed” or a closed-rib profiled roof cladding sheet, on a support structure. The relative movement of the parts makes it possible for “pierce-fixed” and closed rib profiled roof cladding sheets and any other types of profiled roof cladding sheets to move relative to each other or to a roof support structure in a longitudinal direction of the sheets and thereby accommodate relative movement such as during installation or thermal expansion and contraction after installation. The following description focuses on relative movement due to thermal expansion and contraction after installation. The clip of the invention may be used with any type of profiled roof cladding sheet and with cladding sheets generally. The term “profiled roof cladding sheet” is understood herein to mean a metal cladding sheet that is roll-formed or press-formed or otherwise formed to include at least two flat pans separated by an upstanding rib extending along the length of the sheet. The following description relates to four of a number of embodiments of the clip of the invention. • A first-described embodiment secures the ends of longitudinally aligned “pierce-fixed” profiled roof cladding sheets together at the overlap of the sheets and clamps two lines of weather strips in position on a lower one of the two sheets. • A second-described embodiment secures the ends of longitudinally aligned “pierce-fixed” profiled roof cladding sheets together at the overlap of the sheets and clamps only one line of weather strips in position on a lower one of the two sheets. • A third-described embodiment secures a “pierce-fixed” profiled roof cladding sheet to a support structure. • A fourth-described embodiment is a modification of the first part of the first embodiment 30 First embodiment Figures 1 to 3 are perspective views illustrating the first embodiment of the two-part clip of the invention, particularly how the two parts 9, 11 of the clip interlock 16 PCT/AU2016/050004 WO 2016/109871 together in an assembled and operative position (see Figure 3) and can slide relative to each other, and a method of installing two longitudinally aligned “pierce-fixed” profiled roof cladding sheets 3, 5 in end to end overlapping relationship on a support structure of a roof that is based on the use of the clip. Figures 6 to 9 are a series of perspective 5 views illustrating further the sequence of steps in the embodiment of the method of installing the sheets 3, 5 shown in Figures 1 to 3. Figures 13 to 17 are perspective, upper, end and side views of the first part of the first embodiment of the two-part clip. Figures 18 to 21 are upper, end and side views of the second part of the first embodiment of the two-part clip. 10 The part 9 is hereinafter referred to as a “first” part 9 and the part 11 is hereinafter referred to as a “second” part 11.

The structural details of the first and second parts 9, 11 are described with reference to Figures 5 to 16.

The “pierce-fixed” profiled roof cladding sheets 3, 5 are standard Trimdek roof 15 cladding sheets manufactured by the applicant. The roof cladding sheets 3, 5 include lengthwise extending ribs 15 separated by flat pans 61. The invention is not confined to these particular profiled roof cladding sheets.

Figure 4 illustrates a final installation step for the two roof cladding sheets 3, 5, with the sheet 5 (which is an upper sheet) positioned in end-end overlapping 20 relationship on the sheet 3 (which is a lower sheet). Basically, Figure 4 also illustrates the installed roof cladding sheets 3, 5. The final step involves inserting screw fasteners 7 through the upper sheet 5 into the second part 11 of the clip. The Figure also illustrates that a plurality of fasteners 7 (and associated clips - not shown) are required to install a plurality of the roof cladding sheets 3, 5 in side by side and end to end 25 overlapping relationship to an underlying roof support structure 51 (not shown in Figures 1 to 3 but shown in Figures 7 to 10).

Figure 5 illustrates the installed roof cladding sheets shown in Figures 1 to 3 in another direction to that shown in Figure 4.

With reference to Figures 1 to 4 and 6, a first step in the installation procedure 30 in relation to one clip involves positioning the lower sheet 3 on the roof support structure 51 (Figure 6). The roof support structure may be any suitable arrangement of rafters and purlins made from any suitable material and being of any suitable structure, 17 PCT/AU2016/050004 WO 2016/109871 and the details of the structure are not part of the invention. In Figures 6 to 9, the roof support structure 51 is shown as a plurality of parallel purlins. Figure 6 shows two purlins 51. The lower end of the lower sheet 3 is secured by fasteners 63 to one purlin 51 and the upper end of the lower sheet 3 rests on the other purlin 51. 5 With reference to Figure 7, after the lower sheet 3 is secured in position by the fasteners 63 as shown in Figure 6, an installer then positions two parallel lines of weather strips 17 across the width of the lower sheet 3 (and across any side by side overlapping roofing sheets 3) at locations spaced back from an upper end 19 of the lower sheet 3. The spacing may be any suitable spacing based on a required overlap of 1 o the upper and lower sheets 3, 5. The purpose of the weather strips 17 is to prevent wind-driven water flowing upwardly along the lower sheet 3 and through a gap between the overlapping sheets 3, 5 into the roof cavity. Basically, the purpose of the weather strips 17 is to close the gap. The weather strips 17 may be any suitable weather strips. For example, the weather strips shown are weather strips described in International 15 application PCT/AU2013/001325 (WO/2014/075149) in the name of the applicant.

With reference firstly to Figures 1 to 3, in the next step in the installation procedure, the installer secures the clip shown in Figure 3 to the support structure by means of a fastener 13. Figure 3 illustrates the clip positioned on a lengthwise extending rib 15 of the lower sheet 3 in an interlocked assembled and operative 2 o position. The clip is positioned in relation to the weather strips 17 so that the first part 9 contacts the upper surface of the weather strips 17 and thereby clamps the weather strips 17 to the rib 15 and holds the weather strips 17 in position. This can best be seen in Figure 1.

Figure 1 illustrates the parts 9, 11 as separate parts. Figure 2 illustrates the parts 2 5 9, 11 as partially interlocked parts. Typically, the parts 9, 11 will be preassembled together in the operative interlocked position shown in Figure 3 with the second part 11 directly on top of and interlocked with the first part 9.

It can be appreciated from Figures 2 and 3 that the first and second parts 9, 11 can be interlocked together by aligning the second part 11 of the clip with the first part 30 9 as shown in Figure 1 and sliding the second part 9 into the operative interlocked position shown in Figure 3. Figure 2 illustrates partially interlocked parts 9, 11. 18 PCT/AU2016/050004 WO 2016/109871

In addition to illustrating the interlocking of the parts 9, 11, Figures 1 to 3 also illustrate the relative sliding movement of the parts 9, 11, for example as would occur in use in response to thermal expansion and contraction of the roofing sheets 3, 5. This relative sliding movement is important in response to thermal expansion and 5 contraction of the installed roofing sheets 3,5- i.e. in the fixed positions shown in

Figure 4.

The above-described step in the installation method is also illustrated in Figure 8. This Figure shows a plurality of the clips positioned on respective ribs 15 of the lower cladding sheet 3 shown in the Figure. Figure 8 also shows two fasteners 13 1 o positioned to secure two clips to the purlin 51.

With reference to Figures 4 and 9, in the next step in the installation procedure, the installer positions the upper roof cladding sheet 5 over the clip(s) with a required overlap and with a rib(s) 15 of the upper sheet(s) 5 positioned on the second part 11 of the clip(s). As can be seen from the Figures, the second part 11 of the clip(s) is shaped 15 to generally conform to the internal shape of the ribs 15 of the roof cladding sheets so that the upper sheet(s) 5 sits snuggly on the second part 11 of the clip(s). Essentially, the second part 11 of the clip(s) is shaped to form a suitable mounting platform for a rib(s) 15 of the upper sheet(s) 5.

In the final step of the installation procedure, the installer then inserts the 2 o fasteners 7 through the upper sheet(s) 5 and into the second part 11 of the clip(s) to secure the upper sheet 5 to the second part 11 of the clip(s) - as illustrated in Figures 4 and 9 - with the result being positioning the upper and lower sheets 3, 5 in end-to-end overlapping relationship.

Figures 10 and 11 illustrate the installed roof described above. Figure 10 is a 25 vertical cross-section through installed roof cladding sheets 3, 5 illustrating the assembly of the two parts 9, 11 of the first embodiment of the clip and the position of the clip in relation to the profiled roof cladding sheets. Figure 11 is an exploded side view illustrating the positions of the first embodiment of the clip, the roof cladding sheets 3, 5, and the weather strips 17 prior to securing the assembly with fasteners 7, 13 3 0 to the underlying roof support structure 51.

Figure 12 is a perspective view of a slightly modified form of the assembled two-part clip of the invention shown in Figures 1 to 3, 8 and 9. 19 PCT/AU2016/050004 WO 2016/109871

In summary, typically, in use of the clip to hold together upper and lower roof cladding sheets 3, 5 in end-to-end overlapping relationship, the first part 9 of the clip is hard-fixed to the top of the rib 15 of the lower roof cladding sheet 3 and the underlying roof support structure using standard screw fasteners (i.e. same fasteners #12-14x45, or 5 equivalent, that fix the lower sheet). The second part 11 of the clip interlocks with the first part and provides a nominal gap of 20mm (or any other suitable gap) and thus reduces the traditional step/expansion 45mm gap by 25mm. As can be appreciated from Figures 1 to 3, the first and second parts 9, 11 of the clip interlock in a way that allows easy sliding movement between the parts. The rib of the upper roofing sheet 5 ίο fits snugly onto the second part 11 of the clip and the upper roofing sheet 5 is hard-fixed to the second part 11. Screw fasteners 7 fix the upper roofing sheet 5 to the second part 11. These fasteners need only be short screws. These short screws may be standard walling screw fasteners (i.e. the standard #10-16x16 screws specified for wall pan fixing of Trimdek and other walling installations). 15 Two additional optional steps in the installation procedure are steps that are carried out after the installer has fastened the clip to the lower sheet 3 and the support structure 51. The optional steps involve turning up the upper ends 19 of the lower sheet 3 to form barriers at the upper end of the lower sheet 3 and turning down the lower ends of the upper sheet 5 to form barriers at the lower end of the upper sheet 5. It can readily 2 0 be appreciated that when the upper sheet 5 is positioned in end-to-end overlapping relationship on the lower sheet 3, the upturned and downtumed ends prevent vermin and birds accessing the roof.

With reference to Figures 5 to 9, the first part 9 of the clip includes a body portion in the form of a web. The web has three sections, namely a central section 21a 25 and two outer sections 21b. The first part 9 of the clip also includes two flanges 23 having outer end sections 35 extending outwardly and in this embodiment downwardly from opposite side edges of the central web section 21a. The purpose of the flanges 23 is to facilitate interlocking the first and the second parts 9, 11 together. The central web section 21a includes an opening 25 for a fastener, such as the fastener 13 shown in 3 0 Figure 1. 20 PCT/AU2016/050004 WO 2016/109871

The first part 9 of the clip is formed so that, in use as shown in Figure 3, the web contacts and is supported by the top wall of the rib 15 of the lower roof cladding sheet 3 and the flanges 23 extend outwardly and downwardly from opposite sides of the rib 15.

The outer sections 21b of the web of the first part 9 include two upwardly 5 curved side walls 41 on opposite side edges of the web sections 21b to facilitate locating the second part 11 of the clip on the first part 9. The outer sections 21b of the web also act as elements that, in use, extend over and retain the weather strips 17 in position in the above-described two lines of the weather strips 17.

With reference to Figures 10 to 13, the second part 11 of the clip includes a ίο body portion in the form of a web. The web has three sections, namely a central section 27a and two outer sections 27b. The web is formed to substantially overlie the web of the first part 9 when the clip is in the assembled and operative position.

The second part 11 of the clip also includes two flanges 29 extending outwardly and downwardly from opposite side edges of the central web section 27a and in-turned 15 lips 31 at the ends of the flanges 29. The flanges 29 and the in-turned lips 31 of the second part 11 define parallel channels 33 (see Figure 12) on opposite sides of the web 27 that are adapted to receive the outer end sections 35 of the flanges 23 of the first part 9 and interlock the first and the second parts 9, 11 together.

The central web section 27a of the second part 11 includes an opening 37 that is 2 o aligned vertically with the opening 25 in the central web section 21 of the first part 9 when the parts 9, 11 are in the operative interlocked position of the clip shown in Figure 3 so that the fastener 13 shown in Figure 1 can be inserted through the aligned openings and secure the first part 9 to the support structure.

The second part 11 also includes end flanges 69 extending downwardly from 25 ends of the outer web sections 27b. The end flanges are formed as barriers for vermin and birds to end the roof via the clip.

The outer web sections 27b of the second part 11 of the clip include two other flanges 39 extending outwardly and downwardly from opposite side edges of the outer web sections 27b for contacting the outer web sections 21b of the first part 9 and 30 spacing the second part 11 above the first part 9 with a predetermined clearance of the second part 11 above the first part 9. 21 PCT/AU2016/050004 WO 2016/109871

In the assembled and operative position of the clip, the outer web sections 27b of the second part 11 are directly above the two outer web sections 21b of the first part 9 and when a person stands on the clip there is load transfer directly through the second part 11 to the first part 9 and then to the underlying roof support structure 51. 5 The spacing between the two upwardly curved side walls 41 of the first part 9 is greater than the spacing between the two other flanges 39 of the second part 11 so that, in use, the two other flanges 39 of the second part 11 fit inside the two upwardly curved side walls 41 of the first part 9 and the two upwardly curved side walls 9 prevent lateral movement of the second part 11 with respect to the first part 9. ίο Further to the description above in relation to Figures 1 to 3, the first and second parts 9, 11 of the clip are formed so that the second part 11 can be interlocked with the first part 9 by positioning the second part 11 so that the channels 33 are aligned longitudinally with the ends 35 of the flanges 23 of the first part 9 and then moving the second part 11 towards the first part 9 so that the channels 33 of the second part 11 slide 15 along the end sections 35 of the flanges 23 of the first part 9. In effect, the interlocked position is a position in which the end sections 35 of the flanges 23 of the first part 9 are received in the channels 33 of the second part 11.

It can be appreciated that this sliding movement of the parts 9, 11 that allows the parts 9, 11 to be interlocked together in the first instance during assembly of the clip 2 o also allows subsequent sliding movement of the upper and lower roof cladding sheets 3, 5 in a lengthwise extending direction of the sheets 3, 5 for example in response to thermal expansion and contraction of the sheets 3, 5 when the sheets 3, 5 are in an installed position on the clip. More particularly, in the installed position, the lower part 9 of the clip is fixed to the lower sheet 3 and the support structure and the upper part 11 25 is fixed to the upper sheet 5. The parts 9, 11, by virtue of being slidable relative to each other, therefore allow relative sliding movement of the sheets 3, 5 in response to thermal expansion and contraction.

The clip also includes an assembly for locking the parts 9, 11 together on assembly of the clip and prior to and during installation of the clip on a roof. The 3 o locking assembly is formed so that the parts 9, 11 can move relative to each other as required during installation and in response to thermal expansion and contraction of the roof cladding sheets 3, 5 when an applied force exceeds a threshold value. 22 PCT/AU2016/050004 WO 2016/109871

The locking assembly includes locking elements in the form of (a) a notch 73 in the outer end section 35 of each flange 23 of the first part 9 and (b) a projection 75 extending inwardly into each channel 33 of the second part 11. The projections 75 are pressed in sections of the flanges 29 of the second part 11. With this arrangement, in 5 use, when the parts 9, 11 are positioned together in an assembled clip with the projections 75 extending into the notches 73, the notches 73 provide resistance to sliding movement of the second part 11 relative to the first part 9 until an applied force on the parts 9, 11 (for example due to expansion/contraction of the roofing sheets 3, 5) is such as to disengage the notches 73 and the projections 75. 10

Second embodiment

The same reference numerals are used in Figures 22 to 24 to describe the same structural features in the first embodiment shown in Figures 1 to 21.

Figure 23 is a side view of the first part 9 of the second embodiment of the clip, 15 Figure 24 is a side view of the second part 11 of the clip, and Figure 22 is an end view of an assembled second embodiment of the clip and fasteners 7, 13 retaining the ends of longitudinally aligned “pierce-fixed” profiled roof cladding sheets 3, 5 together and to an underlying roof support structure 51 at the overlap of the sheets 3, 5.

The clip is formed to be used in situations where there is only one line of 2 o weather strips 17 (not shown in the Figures).

Basically, as a consequence of the use of the clip with a single line of weather strips 17, the clip of the second embodiment is a cut-down version of the clip of the first embodiment.

More particularly, the first part 9 of the clip comprises a central web section 21a 2 5 and only one outer web section 21b, with the outer web section 21b being provided to hold down weather strips 17 in the single line of weather strips . In addition, the second part 1 lof the clip comprises a central web section 27a and only one outer web section 27b adapted to overlie the corresponding web sections of the first part 9 when the clip is in the assembled and operative position shown in Figure 22. 30 The installation method for the second embodiment is the same as that described above for the first embodiment, with the exception that there is a single rather than two lines of weather strips 17. 23 PCT/AU2016/050004 WO 2016/109871

Third embodiment

The same reference numerals are used on Figures 25 to 27 to describe the same structural features in the first and second embodiments shown in Figures 1 to 22. 5 Figure 26 is a side view of the first part 9 of the third embodiment of the clip,

Figure 27 is a side view of the second part 11 of the clip, and Figure 25 is an end view of an assembled third embodiment of the clip and fasteners 7, 13 retaining the end of a “pierce-fixed” profiled roof cladding sheet 5 to an underlying roof support structure 51.

The clip is structurally the same as the second embodiment of the clip. 10 In use of the third embodiment, the first part 9 of the clip is secured by means of the fastener 13 to the roof support structure 51, with a block 53 of insulation material positioned as a spacer, and the roof cladding sheet 5 is secured by means of the fastener 7 to the second part 11 of the clip. 15 Fourth embodiment

The fourth embodiment of the clip shown in Figures 28 to 30 is a modification of the first embodiment of the clip shown in Figures 1 to 13, with the modification being to include stiffeners (in the form of ribs 65, 67) in the first part 9 of the clip to improve the overall strength of the clip. 2 o The required strength of the clip in any given situation can be provided by a combination of selection of the material(s) from which the clip is made, the thickness of the parts 9, 11 of the clip, and the structure of the parts 9, 11 of the clip including providing the clip with stiffeners.

The same reference numerals used in Figures 1 to 21 for the first embodiment 25 are used in Figures 28 to 30 to describe the same structural features.

Figures 28 to 30 are upper, end and side views respectively of the first part 9 of the fourth embodiment of the clip. The Figures show that the first part 9 includes (a) a rectilinear rib 65 pressed outwardly from the plane of the central web section 21a of the first part 9 and (b) two elongate ribs 67 (which may be described as “radial” ribs) 30 extending from the rectilinear rib 65 part way along the length of each outer web sections 21b. 24 PCT/AU2016/050004 WO 2016/109871

It is noted that the arrangement of ribs 65, 67 shown in Figures 28 to 30 is not the only possible arrangement of reinforcing ribs for the first part 9 of the clip.

In addition, whilst not shown in any specific Figures, it is noted that embodiments of the second part 11 of the clip may include stiffeners in the form of 5 reinforcing ribs or other suitable structural elements.

Many modifications may be made to the embodiment of the invention described herein without departing from the spirit and scope of the invention.

By way of example, whilst the description of the invention in relation to the drawings focuses on embodiments of the clip that are adapted to secure longitudinally 10 aligned “pierce-fixed” roof cladding sheets to a support structure at the overlap of the sheets, the invention is not confined to use with this type of roof cladding sheet.

By way of example, whilst the description of the clip of the invention focuses on the use of the clip in relation to roof cladding sheets, it can readily be appreciated that the invention is not so limited and the clip of the invention may be used with cladding 15 sheets that are used in other applications, such as to form fences and walls.

By way of example, whilst the embodiments of the clip shown in the Figures include particular arrangements of stiffeners in the form of ribs, it can readily be appreciated that the invention is not so limited and the clip of the invention may include any suitable arrangements of stiffeners. 2 0 In the claims which follow, and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word “comprise” and variations such as “comprises” or “comprising” are used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the end lap system and 2 5 components of the end lap system as disclosed herein. 25

Claims

1. A clip for securing two longitudinally aligned roof cladding sheets, such as a “pierce-fixed” or a closed-rib roof cladding sheet, to a support structure at an overlap of the ends of the cladding sheets, with the clip including a first part adapted to be positioned on an upper surface of a lower roof cladding sheet that is positioned on the support structure and to be fastened to the support structure and thereby clamp the lower cladding sheet to the support structure, and a second part adapted to have an upper roof cladding sheet secured to it, with the first part and the second part being adapted to interlock together to be slidable with respect to each other in a way that allows the upper roof cladding sheet to move relative to the support structure and the lower cladding sheet in the longitudinal direction of the sheets via relative movement of the parts of the clip.

2. The clip defined in claim 1 includes an opening in the first part of the clip to allow a fastener to be inserted through the opening to secure the first part of the clip and the lower roof cladding sheet to the support structure.

3. The clip defined in claim 1 or claim 2 wherein the second part of the clip is adapted to have the upper roof cladding sheet secured to it by means of a fastener extending through the upper roof cladding sheet into the second part of the clip.

4. The clip defined in claim 3 includes an opening in the second part of the clip to allow the fastener to be inserted through the opening to fasten the upper roof cladding sheet to the second part.

5. The clip defined in claim 1 or claim 2 wherein the second part of the clip is adapted to have the upper roof cladding sheet secured to it by engagement of the second part of the clip with internal parts of the ribs of upper roof cladding sheet.

6. The clip defined in claim 5 wherein the second part of the clip includes formations such as tabs or other members that are adapted to engage internal parts of the ribs of the upper roof cladding sheet.

7. The clip defined in any one of the preceding claims wherein the first and the second parts of the clip are formed so that the clip can provide sufficient downward support during installation of a roof and for foot traffic on the roof.

8. The clip defined in any one of the preceding claims wherein the first part of the clip includes a body portion in the form of a web and two flanges extending outwardly and optionally downwardly from opposite side edges of the web to facilitate interlocking the first and the second parts together.

9. The clip defined in claim 8 wherein the first part of the clip is formed so that, in use, the web contacts and is supported by a rib of the lower cladding sheet with the flanges of the first part extending outwardly and downwardly from the rib when the lower cladding sheet is a profiled sheet having at least two pans separated by a rib.

10. The clip defined in claim 8 or claim 9 wherein the web of the first part of the clip includes an opening for a fastener to be inserted through the opening to secure the first part and the lower cladding sheet to the support structure, thereby clamping the lower cladding sheet to the support structure.

11. The clip defined in any one of claims 8 to 10 wherein the second part of the clip includes a body portion in the form of a web and two flanges extending outwardly and downwardly from opposite side edges of the web and in-turned lips at the ends of the flanges, with the flanges and the in-turned lips of the second part defining parallel channels on opposite sides of the web that are adapted to receive outer end sections of the flanges of the first part and interlock the first and the second parts together so that the parts are slidable with respect to each other.

12. The clip defined in claim 11 wherein the first and second parts of the clip are formed so that the second part can be interlocked with the first part by positioning the second part so that the channels are aligned longitudinally with the ends of the flanges of the first part and then moving the second part towards the first part so that the channels slide along the end sections of the flanges of the first part and, in effect, position the end sections in the channels.

13. The clip defined in claim 11 or claim 12 includes an assembly for locking the first and second parts together

14. The clip defined in claim 13 wherein the locking assembly includes locking elements on the first and second parts of the clip that are adapted to cooperate together to lock the parts together.

15. The clip defined in claim 14 wherein the locking assembly includes a notch or other suitable formation in the outer end section of each flange of the first part of the clip and a complementary projection extending inwardly into each channel of the second part of the clip, whereby in use when the parts are positioned together with the projections extending into the notches, the notches provide resistance to sliding movement of the second part relative to the first part until an applied force on the parts is such as to disengage the notches and the projections.

16. The clip defined in any one of the claims 11 to 15 wherein the web of the second part of the clip includes an opening that is aligned vertically with the opening in the web of the first part of the clip so that a fastener can be inserted through the aligned openings and secure the first part and the lower cladding sheet to the support structure, thereby clamping the lower cladding sheet to the support structure.

17. The clip defined in claim 16 wherein the web of the second part of the clip includes two other flanges extending outwardly and downwardly from opposite side edges of the web for contacting the web of the first part of the clip and spacing the second part above the first part with a predetermined clearance of the second part above the first part.

18. The clip defined in any one of the preceding claims 11 to 17 wherein the web of the first part of the clip includes two upwardly curved side walls on opposite side edges of the web to facilitate locating the two other flanges of the second part in relation to the first part.

19. The clip defined in claim 18 wherein the spacing between the two upwardly curved side walls of the first part is greater than the spacing between the two other flanges of the second part so that, in use, the two other flanges of the second part fit inside the two upwardly curved side walls of the first part and the two upwardly curved side walls prevent lateral movement of the second part with respect to the first part.

20. The clip defined in any one of claims 11 to 19 wherein the web and the flanges of the second part of the clip are formed so that a rib of the upper roof cladding sheet can fit snuggly over the web and the flanges when the upper cladding sheet is a profiled sheet having at least two pans separated by a rib.

21. The clip defined in any one of the preceding claims being sold in a preassembled arrangement of the first and the second parts of the clip.

22. The clip defined in any one of the preceding claims wherein the first part of the clip is adapted to retain a weather strip in a selected position on the lower cladding sheet.

23. A roof support structure, a plurality of upper roof cladding sheets in side by side overlapping relationship, a plurality of lower roof cladding sheets in side by side overlapping relationship, with the upper and the lower cladding sheets being in an end to end, i .e. end lap, relationship, a line of the clips defined in any one of claims 1 to 22 holding the upper and the lower roof cladding sheets on the support structure, and a line of the weather strips at least partially filling gaps between the upper and the lower cladding sheets on one side of the line of clips.

24. The roof defined in claim 23 further includes another line of weather strips at least partially filling gaps between the roof cladding sheets and the support structure or gaps between the upper and the lower cladding sheets on the opposite side of the line of clips.

25. A method of installing a roof cladding sheet on a support structure of a roof using the clip defined in any one of claims 1 to 22 that includes the steps of: (a) fastening the first part of the clip onto the underlying roof support structure; and (b) securing, for example by means of fasteners, the cladding sheet onto the second part of the clip.

26. A method of installing roof cladding sheets in end to end overlapping relationship on a support structure of a roof using the clip defined in any one of claims 1 to 22 that includes the steps of: (a) laying a plurality of lower cladding sheets onto an underlying roof support structure in side by side overlapping relationship; (b) positioning a plurality of the above-described clip on the lower cladding sheets and forming a line of clips across the width of the sheets; (c) fastening the clips to the lower cladding sheets and the underlying roof support structure, thereby clamping the lower cladding sheet to the support structure; and (d) successively laying a plurality of upper cladding sheets in side by side overlapping relationship and in end to end overlapping relationship onto the second parts of the clips; and (e) securing, for example by means of fasteners, each upper cladding sheet to the second parts of the clips.

27. The method defined in claim 26 further includes positioning a plurality of weather strips across the upper section of the lower cladding sheets in a continuous line before step (b) of forming the line of clips across the width of the sheets.

28. The method defined in claim 27 further includes positioning another a plurality of weather strips across the upper section of the lower cladding sheets in another continuous line that is parallel to the existing line of weather strips before step (b) of forming the line of clips across the width of the sheets.

29. The method defined in any one of claims 26 to 28 wherein the roof cladding sheets are profiled sheets with each sheet having at least two pans separated by an upstanding rib and step (b) of the method includes positioning the clips on the ribs of the lower cladding sheets.

30. The method defined in claim 29 includes turning up the upper ends of the pans of the lower roof cladding sheets before step (d) of laying the upper cladding sheets onto the second parts of the clips.

31. The method defined in claim 29 or claim 30 includes turning down the lower ends of the pans of the upper cladding sheets before step (d) of laying the upper cladding sheets onto the second parts of the clips.

32. A clip for securing a cladding sheet, such as a “pierce-fixed” or a closed-rib roof cladding sheet, on a support structure, with the clip including a first part adapted to be fastened to the support structure and a second part adapted to have the cladding sheet secured to it, with the first part and the second part being adapted to interlock together in a way that allows relative movement of the parts that can accommodate relative movement of the cladding sheet and the support structure in a longitudinal direction of the sheet.