CA2751134A1

CA2751134A1 - Snap-lock trim systems for wall panels and related methods

Info

Publication number: CA2751134A1
Application number: CA 2751134
Authority: CA
Inventors: Austin Daniel Holder
Original assignee: General Trim Products Ltd.; Austin Daniel Holder
Current assignee: GENERAL TRIM PRODUCTS Ltd
Priority date: 2011-08-30
Filing date: 2011-08-30
Publication date: 2011-12-19

Abstract

The invention relates to a multi-component butt-end or corner perimeter trim structure. The structure comprises a back plate having a base portion and a connecting portion, and a top cap having a cap portion and a connecting portion.
The back plate and the top cap are coupled via coupling of the back plate connecting portion and the top cap connecting portion to form an assembled butt perimeter trim structure wherein the assembled perimeter trim structure defines at least a channel for trimming the edges of the wall panels.

Description

SNAP-LOCK TRIM SYSTEMS FOR WALL PANELS AND RELATED
METHODS
Technical Field [0001] The present invention relates to trim systems for wall panels.
Particular embodiments provide trim systems, components therefor, and related methods for producing paneled walls.

Background [0002] It has become increasingly common and fashionable to install wall panels on the exterior or interior of walls. The wall panels may provide functional benefits (e.g., insulation) and/or improve the aesthetics of the walls. The wall panels may be made of fiber cement, similar cementitious materials, composite materials or the like.
When assembling an array of individual wall panels to produce a finished wall surface, trim components are typically used to trim the edges of the wall panels and to thereby provide a finished appearance to the wall. A typical wall panel trim system comprises vertically extending perimeter trim components, vertically extending internal trim components, and horizontally extending trim components. The vertically extending and horizontally extending trim components form a grid-like pattern on the wall surface. Perimeter trim components are used at edges of a wall surface, e.g., at a vertically extending corner of the wall, or at a break in the wall pattern such as a window or door. Internal trim components are used at internal locations on a wall surface spaced apart from the edges.

[0003] FIG. 1 shows in cross section an example prior art perimeter trim component I OA. Prior art perimeter trim component 1 OA is a single-piece extruded elongate member having a U-shaped cross section that has a channel l OC for receiving an edge 14A of a wall panel 14. FIG. 1 also shows an example prior art single-piece internal trim component IOB having an H-shaped cross-section which defines a pair of U-shaped channels I OD and a wall panel 14 installed between components IOA and I OB. In operation, perimeter trim component IOA and internal trim component 1 OB are initially mounted to a wall substrate 16 at spaced apart locations and then wall panel 14 is installed into channels l OC, I OD of trim components 1 OA, l OB. It is not easy to insert an edge 14A of wall panel 14 into the U-shaped channels l OC, I OD of trim component I OA, I OB. It is typically necessary to insert one edge 14A of wall panel 14 into a corresponding one of U-shaped channels l OC, I OD and then bend or deform panel 14, so that the other edge 14A of panel 14 may be inserted into the other one of channels l OC, I OD. Edges 14A
of wall panel 14 and/or wall panel 14 itself may be damaged, broken or deformed when panel 14 is deformed to insert edges 14A into the U-shaped channels IOC, IOD.
Additionally, once wall panel 14 is installed, it is not easy to remove wall panel 14 as edges 14A of wall panel 14 are inserted into U-shaped channels l OC, I OD and wall panels 14 must be bent or deformed to remove panel 14.

[0004] There is a general desire for trim systems, components, and methods that would allow efficient installation and/or removal of wall panels.

Brief Description of Drawings [0005] In drawings which show non-limiting embodiments of the invention:

[0006] FIG. 1 shows a wall panel installed between a prior art perimeter trim component and an internal trim component.

[0007] FIG. 2A is a cross-sectional view of a back plate of a perimeter trim structure according to an embodiment of the invention.

[0008] FIG. 2B is an isometric view of the FIG. 2A back plate.

[0009] FIG. 2C is an enlarged cross-sectional view of a portion of the FIG. 2A
back plate.

t Y

[0010] FIG. 3A is a cross-sectional view of a top cap of a perimeter trim structure according to an embodiment of the invention.

[0011] FIG. 3B is an isometric view of the FIG. 3A top cap.

[0012] FIG. 3C is an enlarged cross-sectional view of a portion of the FIG. 3A
top cap.

[0013] FIG. 4 is a cross-sectional view of a perimeter trim structure comprising the FIG. 2A back plate and the FIG. 3A top cap according to an embodiment of the invention.

[0014] FIGS. 5A to 5C show an example method of using the FIG. 4 perimeter trim structure to trim a wall panel.

[0015] FIG. 6A is a cross-sectional view of a back plate of an outside corner perimeter trim structure according to an embodiment of the invention.

[0016] FIG. 6B is an isometric view of the FIG. 6A back plate.

[0017] FIG. 7A is a cross-sectional view of a top cap of an outside corner perimeter trim structure according to an embodiment of the invention.

[0018] FIG. 7B is an isometric view of the FIG. 7A top cap.

[0019] FIG. 8A is a cross-sectional view of an outside corner perimeter trim structure comprising the FIG. 6A back plate and the FIG. 7A top cap according to an embodiment of the invention.

[0020] FIG. 8B is a cross-sectional view of the FIG. 8A outside corner perimeter trim structure with two wall panels.

[0021] FIG. 9A is a cross-sectional view of another example embodiment of a top cap of an outside corner perimeter trim structure.

[0022] FIG. 9B is a cross-sectional view of another example embodiment of a top cap of an outside corner perimeter trim structure.

[0023] FIG. 1 OA is a cross-sectional view of a back plate of an inside corner perimeter trim structure according to an embodiment of the invention.

[0024] FIG. I OB is an isometric view of the FIG. 1 OA back plate.

[0025] FIG. 11A is a cross-sectional view of a top cap of an inside corner perimeter trim structure according to an embodiment of the invention.

[0026] FIG. 11B is an isometric view of the FIG. 11A top cap.

[0027] FIG. 12A is a cross-sectional view of an inside corner perimeter trim structure according to an embodiment of the invention.

[0028] FIG. 12B is a cross-sectional view of the FIG. 12A outside corner perimeter trim structure with two wall panels.

[0029] FIG. 13A is a cross-sectional view of a horizontal trim component which may be used in trim systems according to various embodiments.

[0030] FIG. 13B is an isometric view of the FIG. 13A horizontal trim component.

[0031] FIG. 14A is a cross-sectional view of a J-shaped soffit trim component.

[0032] FIG. 14B is an isometric view of the FIG. 14A J-shaped soffit trim component.

[0033] FIGS. 15A to 15C are cross-sectional views of an internal trim structure, which may be used in trim systems according to various embodiments.

[0034] FIGS. 16A to 16C are cross-sectional views of another internal trim structure which may be used in trim systems according to various embodiments.

[0035] FIGS. 17 and 18 are exploded and assembled isometric views showing a horizontal trim component interacting with a perimeter trim back plate and an internal trim back plate.

[0036] FIG. 19 is a front plan view of a wall section comprising an array of wall panels and a trim system which trims the wall panels.

[0037] FIGS. 20 and 21 are exploded and assembled isometric views showing a perimeter trim top cap interacting with two perimeter trim back plates in an offset fashion according to a particular embodiment.

[0038] FIGS. 22 and 23 are exploded and assembled isometric views showing an outside corner top cap interacting with two outside corner back plates in an offset fashion according to a particular embodiment.

[0039] FIG. 24 is a cross-sectional view of a perimeter trim structure according to another embodiment used to trim an edge of a wall panel.

[0040] FIG. 25 is a cross-sectional view of an outside corner trim perimeter structure according to another embodiment used to trim the edges of a pair of wall panels.

[0041] FIG. 26 is a cross-sectional view of an inside corner perimeter trim structure according to another embodiment used to trim the edges of a pair of wall panels.

Detailed Description [0042] Throughout the following description, specific details are set forth in order to provide a more thorough understanding of the invention. However, the invention may be practiced without these particulars. In other instances, well known elements have not been shown or described in detail to avoid unnecessarily obscuring the invention. Accordingly, the specification and drawings are to be regarded in an illustrative, rather than a restrictive, sense.

[0043] One aspect of the invention provides a trim system for wall panels. The trim system may comprise a number of components for installing a paneled wall having an array of individual wall panels. The trim system may comprise various multi-component perimeter trim structures including one or more of. a multi-component butt-end perimeter trim structure, a multi-component outside corner perimeter trim structure and a multi-component inside corner perimeter trim structure.
The system may also include multi-component internal trim structures, and horizontal trim components.

[0044] One aspect of the invention provides a multi-component butt-end trim structure. FIG. 4 is a cross-sectional view of a multi-component butt-end trim structure 12 according to a particular embodiment. Trim structure 12 is a type of perimeter trim structure which may be used at a butt edge of a wall surface, at a wall intersection, at door and window openings, and/or the like. Trim structure 12 of the illustrated embodiment comprises a butt-end back plate 12A and a butt-end top cap A

- / -12B shown best in FIGS. 2B and 3B respectively. When installed on a vertically extending wall, butt-end trim structure 12 extends vertically along an edge of a wall surface and trims the vertical edges of wall panels. Of course, butt-end trim structure 12 may also be used on walls that are not vertically extending. The orientation and angle of butt-end trim structure 12 as installed may vary depending on the orientation and angle of the wall surface on which butt-end trim structure 12 is mounted.

[00451 Butt-end trim structure 12 of the FIG. 4 embodiment comprises a butt-end back plate 12A shown in FIGS. 2A and 2B and a butt-end top cap 12B shown in FIGS. 3A and 3B. Butt-end back plate 12A and butt-end top cap 12B may be fabricated from metal (e.g. aluminum), plastic (e.g., PVC) or other suitable material.
Butt-end back plate 12A and butt-end top cap 12B may be fabricated by extrusion and may therefore have uniform cross sections. In other embodiments, back plate and top cap 12B may be fabricated using molding (e.g., injection molding) techniques or other suitable fabrication techniques. Both butt-end back plate 12A and butt-end top cap 12B may be fabricated to have any desired longitudinal lengths (e.g., 10 feet.
16 feet, 20 feet, or the like). After fabrication, butt-end back plate 12A and butt-end top cap 12B may be cut into any desired length for shipping, storage, or installation.
As explained in more detail below, when top cap 12B is coupled to back plate 12A, top cap 12B and back plate 12A together define a U-shaped channel 12C for receiving the edge 14A of a wall panel 14.

[0046) FIGS. 2A and 2B are cross-sectional and isometric views of a butt-end back plate 12A. Butt-end back plate 12A comprises a base portion 12D and a connecting portion 12E connected to base portion 12D. Base portion 12D defines a generally flat surface for abutting against wall substrate 16. FIGS. 3A and 3B
are cross-sectional and isometric views of a butt-end top cap 12B. Butt-end top cap 12B
comprises a cap portion 121 and a connecting portion 12J. Cap portion 121 defines an outer surface. In FIG. 3A, the outer surface of cap portion 121 is generally flat, although this is not mandatory. In other embodiments, the outer surface of cap portion 121 may be curved. Connecting portion 12J of top cap 12B and connecting portion 12E of back plate 12A are adapted to allow top cap 12B and back plate to be coupled together, by coupling connecting portion 12J of top cap 12B to connecting portion 12E of back plate 12A. Connecting portion 12E and connecting portion 12J may be complementary connecting portions, e.g., connecting portion and connecting portion 12J comprise complementary coupling features.

[0047] The coupling between coupling portions 12E and 12J may provide a "snap lock" coupling wherein one or both of connecting portions 12E and 12J is deformed during coupling thereof and restorative deformative forces which tend to restore the shape of connecting portions 12E, 12J snap the connecting portions 12E, 12J
into a locked coupling configuration with one another.

[0048] In the FIGS. 2A, 2B, 3A, 3B embodiments, connecting portion 12E
comprises a female connecting portion 12S and connecting portion 12J comprises a male connecting portion 12T, and female connecting portion 12S receives a portion of male connecting portion 12T in a concavity thereof. In other embodiments, this configuration could be reversed.

[0049] In the FIG. 2A embodiment, female connecting portion 12S of back plate 12A comprises bars 12F and 12G extending generally orthogonally from base portion 12D. In the illustrated embodiment, bar 12F defines a transverse edge of back plate 12A and bar 12G is spaced apart from bar 12F to define a channel 12H between bars 12F and 12G. In the FIG. 3A embodiment, butt-end top cap 12B comprises a male connecting portion 12T. Male connecting portion 12T of top cap 12B and female connecting portion 12S of back plate 12A are adapted to allow top cap 12B and back plate 12A to be coupled together.

[0050] In the FIG. 2A embodiment, bars 12F, 12G of connecting portion 12E
have transverse protrusions 12K, 12L which project into channel 12H and toward one another near the distal ends from base portion 12D of bars 12F, 12G. FIG. 2C
is an enlarged view of an example transverse protrusion 12K. A person skilled in the art would recognize that transverse protrusion 12L may have features similar to transverse protrusion 12K. In FIG. 2C, transverse protrusion 12K has a first beveled edge 40 distal from base portion 12D and a second beveled edge 42 proximal to base portion 12D. FIG. 2C shows an imaginary line 44 intersecting edge 40 and edge 42.
Imaginary line 44 is parallel to butt-end edge 46 of transverse protrusion 12K. In FIG. 2C, angle a between edge 42 and line 44 is greater than angle I between edge 40 and line 44. In some embodiments, angle a is greater than 45 , whereas angle (3 is less than 45 . Therefore, it is easier to insert male connecting portion 12T
into female connecting portion 12S, but more difficult to get male connecting portion 12T
out of female connecting portion 12S.

100511 In the FIG. 3A embodiment, male connecting portion 12T has a bulbous head 12M. FIG. 3C is an enlarged view of bulbous head 12M. Bulbous head 12M
has beveled edges 48, 50 which may be complimentary to edges 40, 42 of transverse protrusions 12K, 12L. Bulbous head 12M forces bars 12F, 12G apart as inward force is applied to top cap 12B. In FIG. 3C, bulbous head 12M has first (distal) beveled edge 48 and second (proximal) beveled edge 50. FIG. 3C shows an imaginary line intersecting first edge 48 and edge 50. Imaginary line 52 is parallel to the distal-proximal axis 54 of male connecting portion 12T. In FIG. 3C, the angle y between edge 48 and line 52 is greater than the angle 8 between edge 50 and line 52.
In some embodiments, angle y is greater than 45 , whereas angle 6 is less than 45 .
Therefore, it is easier to insert male connecting portion 12T into female connecting portion 12S, but more difficult to get male connecting portion 12T out of female connecting portion 12S.

[00521 The dimensions and shapes of protrusions 12K, 12L and bulbous head 12M are such that male connecting portion 12T can be forcibly inserted into and locked in female connecting portion 12S. When male connecting portion 12T is forcibly inserted into female connecting portion 12S, male connecting portion causes bars 12F, 12G to flex slightly outwardly, allowing bulbous head 12M to pass beyond transverse protrusions 12K, 12L. Once bulbous head 12M has passed beyond transverse protrusions 12K, 12L, the resilience (i.e., restorative deformative forces) of bars 12K, 12L causes bars 12K, 12L to flex back inwardly, thereby locking bulbous head 12M in female connecting portion 12S. The coupling between top cap 12B
and back plate 12A may be reversible. Top cap 12B may be decoupled from back plate 12A by exerting a large enough pulling force on top cap 12B to pull male connecting portion 12T out of female connecting portion 12S.

[0053] Back plate 12A may comprise a convexity 12N at or near the corner of base portion 12D and inner bar 12L. In the FIG. 2A embodiment, convexity 12N
has a generally curved cross section, although this is not necessary. Convexity 12N has a number of advantages. Convexity 12N adds rigidity and stability at the curved junction of base portion 12D and inner bar 12L thereby reducing the potential for warping and twisting. As will be described in more detail below, convexity 12N
also lifts wall panel 14 off of base portion 12D thereby supplying a channel for water drainage and ventilation. As will be explained further below, convexity 12N
also functions as a stop for all the horizontal trim components 26 in the rest of the trim system, enabling the horizontal trim components 26 to fit with unfinished edges hidden behind the top caps 12B while ensuring that the wall panel 14 and top caps 12B appear to be all on the same plane.

[0054] FIGS. 5A-5C show a method of using multi-component butt-end trim structure 12. First, back plate 12A is installed on a wall substrate 16.
Substrate 16 may comprise any suitable structural material (e.g., cement, wood frame, steel frame and/or the like). In FIGS. 5A-5C, wall substrate 16 is shown as continuous, although this is not mandatory. In other embodiments, wall substrate 16 may be discontinuous.
Back plate 12A may be mounted on substrate 16 by any suitable techniques such as nailing, screwing, adhesive and/or the like. Second, a wall panel 14 is mounted on top of base portion 12D of back plate 12A. Wall panel 14 may be mounted on substrate 16 by any suitable techniques such as nailing, screwing, adhesive and/or the like. If back plate 12A is provided with convexity 12N, edge 14A of wall panel may rest on convexity 12N, leaving a space 12P between wall panel 14 and base portion 12D as well as between wall panel 14 and substrate 16 within the wall.
The space 12P provides a channel for water drainage and ventilation. After installation of wall panel 14, top cap 12B is coupled to back plate 12A by forcing connecting portion 12J of top cap 12B into coupling engagement with connecting portion 12E of back plate 12A of back plate 12A. Top cap 12B covers edge 14A of wall panel 14 from the outside such that edge 14A of wall panel 14 may not be seen from the outside of wall. When viewed from the outside, only top cap 12B and wall panel are exposed. Back plate 12A, substrate 16 and edges 14A of wall panel 14 are hidden from view.

[00551 In addition to the snap-lock mechanism described above, a bonding agent may also be applied to connecting portion 12E (e.g., in channel 12H) and or connecting portion 12J to couple connecting portion 12E to connecting portion 12J.
When a bonding agent is used, connecting portion 12J may be provided with or without bulbous head 12M and connecting portion 12E may be provided with or without transverse protrusions 12K, 12L. In some embodiments, the bonding agent may be applied to one or both of connecting portions 12E, 12J to minimize the transmission of moisture through the joint between components 12A, 12B. Such a bonding agent may be co-extruded. Additionally or alternatively, connecting portion 12J and connecting portion 12E may also be coupled using other coupling means, such as friction fit, an adhesive, welding, or a fastener.

100561 Wall panels 14 may be of any suitable shape (e.g., rectangular or square). Wall panels 14 may be of any suitable thicknesses (e.g., 5/16 inch, inch, '/2 inch, 5/8 inch, 1 inch, etc.). Back plate 12A and top cap 12B may be manufactured to have suitable dimensions to accommodate wall panels 14 of any particular thickness. Wall panels 14 may be fiber cement panels, wood panels, composite panels, and/or other types of wall panels. Wall panels 14 may be provided with a desired surface finish. For example, wall panels 14 may be provided with simulated wood grain, abstracts, masonry surfaces and the like. Similarly, wood panels 14 may be provided with a wood veneer, a metal finish, high pressure laminates, and the like. Examples of wall panels 14 include wall panels commercially available under the trademark of James Hardie, Certain Teed, Prodema, Ceraclad, Swiss Pearl, or Eternit.

[00571 One aspect of the invention provides a multi-component outside corner perimeter trim structure. FIG. 8A is a cross-sectional view of an example multi-component outside corner perimeter trim structure 18. Outside corner perimeter trim structure 18 may be used at an outside corner of a wall intersection. When installed on a vertically extending wall intersection, outside corner perimeter trim structure 18 extends vertically along the vertically extending wall intersection. Outside corner perimeter trim structure 18 may also be used on wall intersections that are not vertically extending.

100581 Outside corner perimeter trim structure 18 comprises a generally L-shaped back plate 18A and a generally L-shaped top cap 18B. When back plate 18A and top cap 18B are coupled together, they define two generally U-shaped channels 18C, generally orthogonal (or other substantially non-parallel angle) to each other, each channel 18C capable of receiving edge 14A of wall panel 14.

[00591 FIGS. 6A and 6B are cross-sectional and isometric views of an outside corner back plate 18A. Back plate 18A comprises a generally L-shaped base portion 18D. In FIG. 6A, base portion 18D comprises two arms in a generally orthogonal relationship to one another and define a generally L-shaped surface for abutting against a wall substrate. In other embodiments, the two arms of base portion 18D are in a substantially non-parallel angled relationship to one another (e.g., greater than 5 and less than 175 ). Back plate 18A also comprises a connecting portion 18E
connected to the outside corner at the intersection of the two arms of the generally L-shaped base portion 18D. Connecting portion 18E may have similar features as connecting portion 12E of butt-end perimeter trim structure 12 described above. In the FIG. 6A embodiment, connecting portion 18E is a female connecting portion that comprises bars 18F and 18G extending generally outwardly from the intersection of the two arms of the generally L-shaped base portion 18D. Bars 18F and 18G are spaced apart from each other, defining a channel 18H therebetween.

[0060] FIGS. 7A and 7B are cross-sectional and isometric views of outside corner top cap 18B. In FIG. 7A, top cap 18B comprises a generally L-shaped cap portion 181 and a connecting portion 18J extending from the inside corner at the intersection of the two arms of the generally L-shaped cap portion 181. Connecting portion may have similar features as connecting portion 12J of the butt-end perimeter trim structure described above. Connecting portion 18J of top cap 18B can be inserted and locked into connecting portion 18E of back plate 18A such that the top cap 18B
and back plate 18A are coupled together.

[0061] In the FIG. 6A embodiment, bars 18F, 18G of back plate 18A have transverse protrusions 18K, 18L near the distal end of bars 18F, 18G. In the FIG. 7A
embodiment, connecting portion18J is a male connecting portion and has a bulbous head 18M. The dimensions and shapes of protrusions 18K, 18L and bulbous head 18M are such that connecting portion 18J can be inserted into connecting portion 18E
and then locked therein. However, top cap 18B may be decoupled from back plate 18A if a worker exerts a force large enough to pull connecting portion 18J out of connecting portion 18E.

[0062] Back plate 18A may comprise first convexity 18N at the intersection of base portion 18D and bar 18F and a second convexity 180 at the intersection of base portion 18D and bar 18G. In the FIG. 6A embodiment, convexities 18N, 180 each has a generally curved cross section, although this is not mandatory. The functions and advantages of convexity 18N, 180 are similar to the aforementioned convexity 12N.

[0063] In use, back plate 18A is first mounted on an outside wall corner. The two arms of back plate 18A overlay the two intersecting surfaces of the outside wall corner. Second, two wall panels 14 are mounted, one wall panel on top of each arm of the back plate 18A. If back plate 18A is provided with convexities 18N, 180, edge 14A of wall panel 14 may rest on convexity 18N, 180, leaving a space 18P
between wall panel 14 and base portion 18D (see FIG. 8B). The space 18P provides a channel for water drainage and ventilation. Third, top cap 18B is coupled to back plate 18A
by inserting and locking connecting portion 18J into connecting portion 18E.
Top cap 18B covers the edges of wall panels 14. When viewed from the outside, only top cap 18B and wall panels 14 are exposed. Back plate 18A is hidden from view. As can be seen in FIG. 8B, there is a space 18R between edge 14A of wall panel 14 and top cap 18B. Space 18R provides an additional channel for water drainage and ventilation.

[0064] FIGS. 9A, 9B are alternative embodiments of top cap 18P, 18Q. Top cap 18P comprises two L-shaped structures joined together, with male connecting portion 18J extending from the joint of the two L-shaped structures. Top cap 18Q has a rounded corner, rather than a square corner. Top caps 18Q, 18P may be coupled with back plate 18A in a similar fashion as top cap 18B.

[0065] One aspect of the invention provides a multi-component inside corner perimeter trim structure. FIG. 12A is a cross-sectional view of an example multi-component inside corner perimeter trim structure 20. Inside corner perimeter trim structure 20 may be used at an inside corner of a wall intersection. When installed on a vertically extending wall intersection, inside corner perimeter trim structure 20 extends vertically along the vertically extending wall intersection. Inside corner perimeter trim structure 20 may also be used on wall intersections that are not vertically extending.

[0066] Inside corner perimeter trim structure 20 comprises a generally L-shaped back plate 20A and a generally L-shaped top cap 20B. When back plate 20A and top cap 20B are coupled together, they define two generally U-shaped channels 20C, generally orthogonal to one another, each channel 20C capable of receiving the edge 14A of a wall panel 14.

[0067] FIGS. 1 OA and I OB are cross-sectional and isometric views of an inside corner back plate 20A. Back plate 20A comprises a generally L-shaped base portion 20D and a connecting portion 20E connected to the inside corner at the intersection of the two arms of the generally L-shaped base portion 20D. Connecting portion may have similar features as connecting portion 12E of the butt-end perimeter trim structure described above. In the FIG. 1 OA embodiment, connecting portion 20E
is a female connecting portion and comprises bars 20F and 20G extending from an inside corner at the intersection of the two arms of the generally L-shaped base portion 20D.
Bars 20F and 20G are spaced apart from each other, defining a channel 20H
therebetween.

[0068] FIGS. 11 A and 11 B are cross-sectional and isometric views of inside corner top cap 20B. Top cap 20B comprises a generally L-shaped cap portion 201 and a connecting portion 20J extending outwardly from the corner at the intersection of the two arms of the generally L-shaped cap portion 201. Connecting portion may have similar features as connecting portion 12J of the butt-end perimeter trim structure described above. Connecting portion 20J of top cap 20B can be inserted and locked into the connecting portion 20E of back plate 20A such that the top cap and back plate 20A are coupled together.

[0069] In the FIG. 1 OA embodiment, bars 20F, 20G of back plate 20A have transverse protrusions 20K, 20L near the distal end of bars 20F, 20G. In the FIG.
11A embodiment, connecting portion 20J is a male connecting portion and has a bulbous head 20M. The dimensions and shapes of protrusions 20K, 20L and bulbous head 20M are such that male connecting portion 20J can be inserted into female connecting portion 20E and then locked therein. However, top cap 20B may be decoupled from back plate 20A if a worker exerts a force large enough to pull connecting portion 20J out of connecting portion 20E.

[00701 Back plate 20A may comprise a first convexity 20N near the intersection of base portion 20D and bar 20F and a second convexity 200 at the intersection of base portion 20D and bar 20G. In the FIG. I OA embodiment, convexities 20N, each has a generally curved cross section, although this is not mandatory. The functions and advantages of convexities 20N, 200 are similar to the aforementioned convexity 12N.

[00711 In use, back plate 20A is first mounted on an inside wall corner. The two arms of back plate 20A overlay the two intersecting surfaces of the inside wall corner.
Second, two wall panels 14 are mounted, one wall panel on top of each arm of the back plate 20A. If back plate 20A is provided with convexities 20N, 200, an edge 14A of wall panel 14 may rest on convexity 20N, 200, leaving a space 20P
between wall panel 14 and base portion 20D (see FIG. 12B). The space 20P provides a channel for water drainage and ventilation. Third, top cap 20B is coupled to back plate 20A by inserting and locking connecting portion 20J into connecting portion 20E. Top cap 20B covers the edges of wall panels 14. When viewed from the outside, only top cap 20B and wall panels 14 are exposed. Back plate 20A is hidden from view. As can be seen in FIG. 12B, there is a space 20R between edge 14A
of wall panel 14 and top cap 20B. Space 20R provides an additional channel for water drainage and ventilation.

[00721 One aspect of the invention provides a multi-component internal vertical trim structure. FIG. 16C is a cross-sectional view of an example multi-component internal vertical trim structure 24. Internal vertical trim structure 22 may be used to trim the edges of two adjacent wall panels at an internal location on a wall (i.e., not at a perimeter or terminal edge of a wall). When installed on a vertically extending wall, internal trim structure 24 extends vertically.

[00731 Internal trim structure 24 comprises a back plate 24A and a top cap 24B.
When back plate 24A and top cap 24B are coupled together, they define two generally U-shaped channels 24C, generally parallel and facing away from each other, and each channel 24C capable of receiving the edge 14A of a wall panel 14.
[0074] FIG. 16B is a cross-sectional view of back plate 24A. Back plate 22A
comprises a base portion 24D and a connecting portion 24E extending from a middle region of base portion 24D. In the FIG. 16B embodiment, connecting portion 24E
is a female connecting portion comprises bars 24F and 24G extending orthogonally from base portion 24D. Bars 24F and 24G are spaced apart from each other, defining a channel 24H therebetween.

[0075] FIG. 16A is a cross-sectional view of top cap 24B. Top cap 24B
comprises a cap portion 241 and a connecting portion 24J that extends from the cap portions 241. In the FIG. 16A embodiment, connecting portion 24J of top cap 24B is a male connecting portion and can be inserted and locked into connecting portion 24E
of back plate 24A such that the top cap 24B and back plate 24A are coupled together.
[0076] In the FIG. 16B embodiment, bars 24F, 24G of back plate 24A have transverse protrusions 24K, 24L near the tip of bars 24F, 24G. In the FIG. 16A
embodiment, connecting portion 24J has transverse protrusions 24M. Connecting portion 24J can be inserted into connecting portion 24E and then locked therein.
However, top cap 24B may be decoupled from back plate 24A if a worker exerts a force large enough to pull connecting portion 24J out of connecting portion 24E.
[0077] Back plate 24A may comprise a first convexity 24N near the intersection of base portion 24D and bar 24F and a second convexity 240 at the intersection of base portion 24D and bar 24G. In the FIG. 16B embodiment, convexities 24N, 240 each has a curved cross section. The functions and advantages of convexity 24N, 240 are similar to the aforementioned convexity 12N.

[0078] In use, back plate 24A is first mounted on wall substrate 16. Second, two wall panels are mounted, one on each side of the back plate 24A. Third, top cap 24B
is coupled to back plate 24A by inserting and locking male connecting portion into female connecting portion 24E. Top cap 24B covers the edges of wall panels.
When viewed from the outside, only top cap 24B and wall panels 14 are exposed.
Back plate 24A is hidden from view.

[0079] FIGS. 15A-15C show an alternative embodiment of a multi-component internal vertical trim structure 22. The structure and function of internal vertical trim structure 22 is similar to internal vertical trim structure 24, but the connecting portions 22E, 22J of structure 22 have larger dimensions than structure 22.
Similar structures in FIGS. 15A-15C are labeled using similar reference numerals as in FIGS.

16A-I6C, except that "24" is replaced with "22".

[0080] The trim system according to the present invention may also include horizontally extending trim components such as horizontal trim components 26 and soffit J pieces 28.

[00811 Horizontal trim component 26 may be used to trim a top or bottom horizontal edge of a wall panel 14. FIGS. 13A and 13B are cross-sectional and isometric views of a horizontal trim component 26. Horizontal trim component comprises a flange portion 26A, a ledge portion 26B and a tab portion 26C.
Flange portion 26A is generally parallel to tab portion 26C. The angle between flange portion 26A and ledge portion 26B may be in the range of 90 to 120 . In a particular embodiment, the angle is 96.6 . When the angle is greater than 90 , ledge portion 26B slopes downwardly. The slope of ledge portion 26B allows water to drain away from the wall.

[0082] Horizontal trim component 26 may be used on internal location on a wall surface, or above windows or doors, or at the base of a wall. For finishing or capping the top of a wall, soffit J piece 28 may also be used. FIGS. 14A and 14B are cross-sectional and isometric views of an example soffit J piece 28.

[00831 FIGS. 17 and 18 are exploded and assembled isometric views of a horizontal trim component 26 and two vertical trim structures (a butt-end trim structure 12 and an internal vertical trim structure 22). To better show the interaction between horizontal trim component 26 and butt-end trim structure 12 and internal vertical trim structure 22, top caps 12B, 22B and wall panels 14 are not shown in FIGS. 17 and 18. Horizontal trim component 26 extends from butt-end trim structure 12 to internal vertical trim structure 22. The ends of horizontal trim component 26 stop at convexities 12N and 22N. Flange portion 26A of horizontal trim component 26 overlies base portion 12D of butt-end trim structure 12 and base portion 22D of internal vertical trim structure 22. In some embodiments, because of the overlying feature, a single fastener (not shown) may pass through both flange portion 26A and base portion 12D or both flange portion 26A and base portion 22D to secure horizontal trim component 26, butt-end trim structure 12, and internal vertical trim structure 22 to wall substrate 16 (not shown).

[00841 FIG. 19 is a front plan view of a vertically extending wall section comprising an array of 3x3 wall panels 14. The array of wall panels is trimmed by two butt-end trim structures 12 at the vertical perimeter edges of the wall section, and two internal trim structure 24. It should be recognized that internal trim structures 22 may be used instead of internal trim structure 24. In the FIG. 19 embodiment, only top caps 12A, 24A of butt-end trim structure 12 and internal trim structure 24 are visible to the viewer. Butt-end trim structures 12 and internal trim structures 24 extend from top to bottom of the wall section. The horizontal edges of wall panels 14 are trimmed by a plurality of horizontally extending horizontal trim components 26 which are placed between the vertically extending butt-end trim structures 12 and internal trim structures 24 to form a grid-like pattern. It should be noted that in the FIG. 19 embodiment horizontal trim components 26 are not continuous along the horizontal dimension of the wall section.

100851 The installation of a wall section comprising an array of wall panels may be carried out as follows. First, back plates 12A of butt-end trim structures 12 and back plate 22A or 24A of internal trim structures 22 or 24 are mounted on wall substrate 16. Second, a plurality of horizontal trim components 26 is mounted on wall substrate 16 generally orthogonal to back plates 12A and 22A or 24A in appropriately spaced-apart rows to form a grid. Third, an array of wall panels 14 is mounted on wall substrate 16 in spaces defined by the grid. The upper edge of wall panel 14 is received under tab portion 26C of horizontal trim component 26 above.
The bottom edge of wall panels 14 lies above ledge portions 26B of horizontal trim component 26 below. The two lateral edges of wall panel 14 may sit upon convexities of butt-end trim structures 12 and internal vertical trim structure 22 (or 24). Fourth, top caps 12B and 22B (or 24B) are placed on top of back plates 12A and 22A (or 24A) and locked together. Top caps 12B and 22B (or 24B) cover the two lateral edges of wall panel 14.

[00861 Although it is possible to assemble a butt-end trim structure 12 from a single back plate 12A and a single top cap 12B, it is also possible to assemble a butt-end trim structure 12 from two or more back plate 12A and two or more top cap 12B.
Two or more back plate 12A can join together in an end-to-end relationship to form a back plate assembly. Similarly, two or more top caps 12B can join together in an end-to-end relationship to form a top cap assembly. In an assembly, top caps 12B, may be coterminous with back plates 12A. Alternatively, top caps 12B and back plates 12A may be in an offset or staggered fashion, i.e., the uppermost longitudinal end of top cap 12B is offset from the uppermost longitudinal end of back plate and/or the lowermost longitudinal end of top cap 12B is offset from the lowermost longitudinal end of back plate 12A. Such coterminous and/or offset assemblies can also be assembled from multi-component outside corner perimeter trim structures 18 and multi-component inside corner perimeter trim structures 20.

[00871 FIGS. 20 and 21 are exploded and assembled isometric views of two butt-end trim structure back plates 12A and one butt-end trim structure top cap 12B
in an offset assembly. FIGS. 22 and 23 are exploded and assembled isometric views of two outside corner back plates 18A and one outside corner top cap 18B in an offset assembly. The offset feature is made possible because each trim structure comprises two pieces, i.e., a back plate and a top cap. The offset feature provides a number of advantages. It strengthens the integrity of the assembly and makes the assembly more resistant to bending, warping or twisting. The top caps may visually conceal any bending or twisting commonly taking place at the junction of two abutting back plates. It allows back plates and top caps of different lengths to be assembled together, permitting more versatility. It also allows back plates and top caps to be cut into shorter lengths for ease of transportation and storage and then be assembled at the work site. These advantages would not be achieved if the trim structure is of a single-piece construction.

[0088] The multi-component perimeter trim structure (multi-component butt-end trim structure 12, outside corner perimeter trim structure 18, and inside corner perimeter trim structure 20) according to the present invention provides a number of additional advantages over prior art one-piece perimeter trim components. It allows a wall panel to be easily installed without the risk of the wall panels being damaged, broken or deformed as with prior art one-piece perimeter trim components. It allows a worker to inspect the edge of a wall panel during installation to ensure that the edge has been sealed as per manufacturer's instructions or is not damaged or broken or deformed before installing the top cap to cover the edge. With the prior art one-piece perimeter trim component, a worker cannot inspect the edge of the wall panel when it is forcibly inserted into the channel in the one-piece perimeter trim piece.
The multi-component perimeter structure also allows a worker to remove the top cap to allow removal and replacement of a wall panel that has already been installed or damaged.
With the prior art one-piece perimeter trim component, there is no easy way to remove a wall panel that has already been installed, as the edge of the wall panel is inserted in the U-shaped channel of the one-piece perimeter trim component on both sides of the wall panel .

[0089] The multi-component perimeter trim structure (multi-component butt-end trim structure 12, outside corner perimeter trim structure 18, and inside corner perimeter trim structure 20) according to the present invention is also advantageous over the aluminum reveals wall systems commercially available under the trademark EasyTrim. The EasyTrim system does not use multi-component perimeter trim structures, although it uses multi-component internal trim structures. As a result, in many instances where a wall panel must be installed between two vertical perimeter pieces, the installer experiences the same frustrations as described in the prior art.
The EasyTrim system also requires horizontal trim components to extend the entire horizontal length of a wall section, and the internal trim structures are not continuous from top to bottom of a wall section. As a result, not only is bending, warping and twisting of trim visible at all their vertical perimeter pieces, but also all horizontal joints between the top caps. In contrast, the trim system comprising the multi-component perimeter trim structure according to the present invention allows the internal trim structures to run continuously from top to bottom of a wall section. This increases the strength and integrity of the internal trim structure and hides both horizontal and vertical bending.

100901 As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. For example: the configuration of male and female connecting portions in perimeter trim structures may be reversed. FIGS. 24-26 shows alternative embodiments of butt-end trim structure 12, outside corner perimeter trim structure 18 and inside corner perimeter trim structure 20 respectively wherein the female connecting portion is located on the top cap and the male connecting portion is located on the back plate.

Claims

1. A trim system for trimming edges of wall panels that are mounted over a wall substrate to provide a finished wall, the trim system comprising:
an internal trim structure having a pair of substantially parallel, longitudinally extending internal channels which open to opposing transverse sides of the internal trim structure for receiving a corresponding pair of internal edges of a corresponding pair of wall panels; and a multi-component perimeter trim structure comprising:
a longitudinally extending back plate comprising a base portion defining a substantially flat surface abutting against the wall substrate and a back plate connecting portion on a side of the base portion opposite the abutting surface;
a longitudinally extending top cap comprising a cap portion defining an outer surface and a top cap connecting portion located on a side of the cap portion opposite the outer surface;
wherein the back plate connecting portion is coupled to the top cap connecting portion to thereby couple the back plate to the top cap and to define a longitudinally extending, transversely opening perimeter channel for receiving a perimeter edge of a perimeter wall panel;
the perimeter trim structure located at a longitudinally extending perimeter edge of the wall, the perimeter edge of the wall comprising at least one of: a corner of the wall; and a butt edge that defines an opening in the wall.

2. The trim system according to claim 1 wherein the back plate connecting portion and the top cap connecting portion have complementary shapes.

3. The trim system according to claim 1 wherein the back plate connecting portion is a female connecting portion and the top cap connecting portion is a male connecting portion.

4. The trim system according to claim 1 wherein the back plate connecting portion is a male connecting portion and the top cap connecting portion is a female connecting portion.

5. The trim system according to any one of claims 3 and 4 wherein the female connecting portion comprises two spaced apart bars extending away from the base portion to define a concavity for receiving a protrusion of the male connecting portion.

6. The trim system according to claim 5 wherein one of the bars defines a transverse edge of the perimeter trim structure.

7. The trim system according to claim 5 wherein the protrusion of the male connecting portion comprises a bulbous head and the female connecting portion comprises a pair of transverse protrusions which project from the spaced apart bars inwardly and toward one another for locking the bulbous head in the concavity.

8. The trim system according to claim 7 wherein each of the transverse protrusions comprises a distal beveled edge located relatively far from a base of the concavity and a proximal edge located relatively close to the base of the concavity and an angle between the distal beveled edge and a surface of a corresponding one of the bars is less than the angle between the proximal edge and the surface of the corresponding one of the bars.

9. The trim system according to claim 8 wherein the bulbous head comprises a convexity that is shaped to abut against the distal beveled edges of the transverse protrusions and to thereby force the bars apart from one another, when coupling the back plate connecting portion to the top cap connecting portion.

10. The trim system according to any one of claims 1 to 9 wherein the back plate connecting portion and top cap connecting portion are shaped to provide a snap-lock coupling wherein, during the formation of the snap-lock coupling, one or both connecting portions is first deformed and then restored at least partially toward its original shape and into a locked coupling configuration by restorative deformation forces.

11. The trim system according to any one of claims 1 to 10 wherein the base portion of the back plate extends transversely further than the cap portion of the top cap.

12. The trim system according to any one of claims 1 to 10 wherein the cap portion of the top cap extends transversely further than the base portion of the black plate.

13. The trim system according to any one of claims 1 to 12 wherein a longitudinal edge of the top cap is offset from longitudinal edges of the back plate.

14. The trim system according to any one of claims 1 to 13 wherein the trim system comprises a plurality of longitudinally abutting back plates and a plurality of longitudinally abutting top caps and wherein abutment joints between pairs of longitudinally adjacent back plates are longitudinally offset from abutment joints between pairs of longitudinally adjacent top caps.

15. The trim system according to claim 1 wherein the back plate connecting portion and the top cap connecting portion are coupled via a bonding agent.

16. The trim system according to claim 1 wherein the back plate connecting portion and the top cap connecting portion are coupled by friction fit.

17. The trim system according to any one of claims 1 to 16 wherein the base portion of the back plate comprises a convexity adjacent the connecting portion and inside the transversely opening perimeter channel for spacing the perimeter edge of the wall panel from the base portion of the back plate.

18. The trim system according to any one of claims 1 to 17, further comprising a horizontally extending trim component.

19. The trim system according to claim 18 wherein the horizontally extending trim component is mounted between the internal trim structure and the multi-component perimeter trim structure such that the transverse ends of the horizontally extending trim component are located between the internal trim structure and the multi-component perimeter trim structure.

20. The trim system according to any one of claims 1 to 19 wherein the internal trim structure is a multi-component trim structure comprising a back plate and a top cap.

21. The trim system according to any one of claims 1 to 20 wherein the back plate connecting portion is located at a transverse end of the base portion of the back plate.

22. The trim system according to any one of claims 1 to 21 wherein the top cap connecting portion is located at a transverse end of the top cap of the back plate.

23. The trim system according to any one of claims 1 to 22 wherein:
the base portion of the back plate defines a second substantially flat abutting surface abutting against the wall substrate, the second abutting surface oriented at a non-parallel angle relative to the abutting surface;
the back plate connecting portion is located at an angled intersection of the base portion of the back plate and on the side of the base portion opposite the abutting surface and the second abutting surface;
the cap portion of the top cap defines a second outer surface, the second abutting surface oriented at a non-parallel angle relative to the outer surface;
the top cap connecting portion is located at an angled intersection of the top cap and on a side of the cap portion opposite the outer surface and the second outer surface.

24. The trim system according to claim 23 wherein the coupled back plate and top cap define a second longitudinally extending perimeter channel for receiving a perimeter edge of a second perimeter wall panel, the second perimeter wall panel oriented at a non-parallel angle relative to the perimeter wall panel.

25. A multi-component butt-end perimeter trim structure for trimming perimeter edges of perimeter wall panels mounted over a wall substrate to provide a finished wall, the trim structure comprising:
a longitudinally extending back plate comprising a base portion defining a substantially flat surface for abutting against the wall substrate and a back plate connecting portion located at one transverse end of the base portion and on a side of the base portion opposite the abutting surface, a longitudinally extending top cap comprising a cap portion defining an outer surface and a connecting portion located at a transverse end of the top cap and on a side of the cap portion opposite the outer surface;
wherein the back plate connecting portion is coupleable to the top cap connecting portion to thereby couple the back plate to the top cap and to define a longitudinally extending, transversely opening perimeter channel for receiving a perimeter edge of a perimeter wall panel.

26. The trim structure according to claim 25 wherein the back plate connecting portion and the top cap connecting portion have complementary shapes.

27. The trim structure according to claim 25 wherein the back plate connecting portion is a female connecting portion and the top cap connecting portion is a male connecting portion.

28. The trim structure according to claim 25 wherein the back plate connecting portion is a male connecting portion and the top cap connecting portion is a female connecting portion.

29. The trim structure according to any one of claims 27 and 28 wherein the female connecting portion comprises two spaced apart bars extending away from the base portion to define a concavity for receiving a protrusion of the male connecting portion.

30. The trim structure according to claim 29 wherein one of the bars defines a transverse edge of the perimeter trim structure.

31. The trim structure according to claim 29 wherein the protrusion of the male connecting portion comprises a bulbous head and the female connecting portion comprises a pair of transverse protrusions which project from the spaced apart bars inwardly and toward one another for locking the bulbous head in the concavity.

32. The trim structure according to claim 31 wherein each of the transverse protrusions comprises a distal beveled edge located relatively far from a base of the concavity and a proximal edge located relatively close to the base of the concavity and an angle between the distal beveled edge and a surface of a corresponding one of the bars is less than the angle between the proximal edge and the surface of the corresponding one of the bars.

33. The trim structure according to claim 32 wherein the bulbous head comprises a convexity that is shaped to abut against the distal beveled edges of the transverse protrusions and to thereby force the bars apart from one another, when coupling the back plate connecting portion to the top cap connecting portion.

34. The trim structure according to any one of claims 25 to 33 wherein the back plate connecting portion and top cap connecting portion are shaped to provide a snap-lock coupling wherein, during the formation of the snap-lock coupling, one or both connecting portions is first deformed and then restored at least partially toward its original shape and into a locked coupling configuration by restorative deformation forces.

35. The trim structure according to any one of claims 25 to 34 wherein the base portion of the back plate extends transversely further than the cap portion of the top cap.

36. The trim structure according to any one of claims 25 to 34 wherein the cap portion of the top cap extends transversely further than the base portion of the black plate.

37. The trim structure according to any one of claims 25 to 36 wherein a longitudinal edge of the top cap is offset from longitudinal edges of the back plate.

38. The trim structure according to any one of claims 25 to 37 wherein the trim system comprises a plurality of longitudinally abutting back plates and a plurality of longitudinally abutting top caps and wherein abutment joints between pairs of longitudinally adjacent back plates are longitudinally offset from abutment joints between pairs of longitudinally adjacent top caps.

39. The trim structure according to claim 25 wherein the back plate connecting portion and the top cap connecting portion are coupleable via a bonding agent.

40. The trim structure according to claim 25 wherein the back plate connecting portion and the top cap connecting portion are coupleable by friction fit.

41. The trim structure according to any one of claims 25 to 40 wherein the base portion of the back plate comprises a convexity adjacent the connecting portion and inside the transversely opening perimeter channel for spacing the perimeter edge of the wall panel from the base portion of the back plate.

42. The trim system according to any one of claims 25 to 41 wherein the outer surface of the cap portion is generally flat.

43. The trim system according to any one of claims 25 to 41 wherein the outer surface of the cap portion is curved.

44. A multi-component corner trim structure for trimming perimeter edges of perimeter wall panels mounted over a wall substrate to provide a finished wall, the trim structure comprising:
a longitudinally extending back plate comprising: a base portion defining first and second substantially flat surfaces for abutting against corresponding surfaces of a corner of the wall substrate, the first and second abutting surfaces oriented, with respect to one another, at a non-parallel angle; and a back plate connecting portion located at an angled intersection of the base portion and on a side of the base portion opposite the first and second abutting surfaces;
a longitudinally extending top cap comprising: a cap portion defining first and second outer surfaces, the first and second outer surfaces oriented, with respect to one another, at a non-parallel angle; and a top cap connecting portion located at an angled intersection of the top cap and on a side of the top cap opposite the first and second outer surfaces;
wherein the back plate connecting portion is coupleable to the top cap connecting portion to thereby couple the back plate to the top cap and to define a pair of longitudinally extending perimeter channels for receiving perimeter edges of a corresponding pair of perimeter wall panels, the corresponding pair of perimeter wall panels oriented, with respect to one another, at a non-parallel angle.

45. The trim structure according to claim 44 wherein the back plate connecting portion and the top cap connecting portion have complementary shapes.

46. The trim structure according to claim 44 wherein the back plate connecting portion is a female connecting portion and the top cap connecting portion is a male connecting portion.

47. The trim structure according to claim 44 wherein the back plate connecting portion is a male connecting portion and the top cap connecting portion is a female connecting portion.

48. The trim structure according to any one of claims 46 and 47 wherein the female connecting portion comprises two spaced apart bars extending away from the base portion to define a concavity for receiving a protrusion of the male connecting portion.

49. The trim structure according to claim 48 wherein the protrusion of the male connecting portion comprises a bulbous head and the female connecting portion comprises a pair of transverse protrusions which project from the spaced apart bars inwardly and toward one another for locking the bulbous head in the concavity.

50. The trim structure according to claim 49 wherein each of the transverse protrusions comprises a distal beveled edge located relatively far from a base of the concavity and a proximal edge located relatively close to the base of the concavity and an angle between the distal beveled edge and a surface of a corresponding one of the bars is less than the angle between the proximal edge and the surface of the corresponding one of the bars.

51. The trim structure according to claim 50 wherein the bulbous head comprises a convexity that is shaped to abut against the distal beveled edges of the transverse protrusions and to thereby force the bars apart from one another, when coupling the back plate connecting portion to the top cap connecting portion.

52. The trim structure according to any one of claims 44 to 51 wherein the back plate connecting portion and top cap connecting portion are shaped to provide a snap-lock coupling wherein, during the formation of the snap-lock coupling, one or both connecting portions is first deformed and then restored at least partially toward its original shape and into a locked coupling configuration by restorative deformation forces.

53. The trim structure according to any one of claims 44 to 52 wherein the base portion of the back plate extends transversely further than the cap portion of the top cap.

54. The trim structure according to any one of claims 44 to 52 wherein the cap portion of the top cap extends transversely further than the base portion of the black plate.

55. The trim structure according to any one of claims 44 to 54 wherein a longitudinal edge of the top cap is offset from longitudinal edges of the back plate.

56. The trim structure according to any one of claims 44 to 55 wherein the trim system comprises a plurality of longitudinally abutting back plates and a plurality of longitudinally abutting top caps and wherein abutment joints between pairs of longitudinally adjacent back plates are longitudinally offset from abutment joints between pairs of longitudinally adjacent top caps.

57. The trim structure according to claim 44 wherein the back plate connecting portion and the top cap connecting portion are coupleable via a bonding agent.

58. The trim structure according to claim 44 wherein the back plate connecting portion and the top cap connecting portion are coupleable by friction fit.

59. The trim structure according to any one of claims 44 to 58 wherein the base portion of the back plate comprises a convexity adjacent the connecting portion and inside the transversely opening perimeter channel for spacing the perimeter edge of the wall panel from the base portion of the back plate.

60. A method for assembling a trim system for trimming edges of wall panels that are mounted over a wall substrate to provide a finished wall, the method comprising:
providing a longitudinally extending back plate comprising a substantially flat abutment surface and a back plate connecting portion on a side of the back plate opposite the abutment surface;
providing a longitudinally extending top cap comprising an outer surface and a top cap connecting portion located on a side of the top cap opposite the outer surface;
abutting the abutment surface of the back plate against a corresponding portion of the wall substrate to mount the back plate to the wall substrate;
mounting a wall panel so that the wall panel covers a portion of the back plate and leaves the back plate connecting portion exposed;
coupling the top cap connecting portion to the back plate connecting portion to thereby couple the top cap to the back plate and to locate a perimeter edge of a perimeter wall panel in a longitudinally extending, transversely opening channel defined by the coupled top cap and back plate.

61. A method according to claim 60 wherein mounting the wall panel comprises inserting an internal edge of the perimeter wall panel into a longitudinally extending internal channel of an internal trim structure, the internal trim structure mounted to the wall substrate and the internal edge of the perimeter wall panel opposing the perimeter edge of the perimeter wall structure.

62. A trim system kit for trimming edges of wall panels that are mounted over a wall substrate to provide a finished wall, the kit comprising:
an internal trim structure having a pair of substantially parallel, longitudinally extending internal channels which open to opposing transverse sides of the internal trim structure for receiving a corresponding pair of internal edges of a corresponding pair of wall panels; and a multi-component perimeter trim structure comprising:
a longitudinally extending back plate comprising a base portion defining a substantially flat surface for abutting against the wall substrate and a back plate connecting portion on a side of the base portion opposite the abutting surface;
a longitudinally extending top cap comprising a cap portion defining an outer surface and a top cap connecting portion located on a side of the cap portion opposite the outer surface;
wherein the back plate connecting portion is coupleable to the top cap connecting portion to thereby couple the back plate to the top cap and to define a longitudinally extending, transversely opening perimeter channel for receiving a perimeter edge of a perimeter wall panel;
the perimeter trim structure locatable at a longitudinally extending perimeter edge of the wall, the perimeter edge of the wall comprising at least one of: a corner of the wall; and a butt edge that defines an opening in the wall.
trim structure defines a pair of channels for trimming the edges of the wall panels.

63. The trim system kit according to claim 62 wherein the back plate connecting portion is located at a transverse end of the base portion of the back plate.

64. The trim system kit according to any one of claims 62 to 63 wherein the top cap connecting portion is located at a transverse end of the top cap of the back plate.

65. The trim system kit according to claim 62 wherein:
the base portion of the back plate defines a second substantially flat abutting surface abutting against the wall substrate, the second abutting surface oriented at a non-parallel angle relative to the abutting surface;
the back plate connecting portion is located at an angled intersection of the base portion of the back plate and on the side of the base portion opposite the abutting surface and the second abutting surface;
the cap portion of the top cap defines a second outer surface, the second abutting surface oriented at a non-parallel angle relative to the outer surface;
the top cap connecting portion is located at an angled intersection of the top cap and on a side of the cap portion opposite the outer surface and the second outer surface.

66. The trim system kit according to claim 65 wherein the coupled back plate and top cap define a second longitudinally extending perimeter channel for receiving a perimeter edge of a second perimeter wall panel, the second perimeter wall panel oriented at a non-parallel angle relative to the perimeter wall panel.