Patent Application
20180171621
The present disclosure relates in general to precast cladding panels, and in particular to hangers cast into precast cladding panels to facilitate mounting of the panels on a supporting structure.
Precast panels of various sizes and shapes are widely used as cladding on building walls, serving as components of building envelope systems intended to prevent infiltration of rain and outside air into the building. Precast cladding panels are commonly made of concrete, but may also be made with other cast materials known in the construction field. Concrete cladding panels are common on large structures such as office buildings, but they are also used on residential housing structures as an alternative to traditional cladding materials such as wood siding and brick.
Whether installed on large or small buildings, it is desirable for cladding panels to be mounted in such a way that there will be a continuous air space between the rear (i.e., inner) faces of the panels and the supporting structure, while at the same time providing reliable structural support for the panels, both to transfer the vertical weight of the panels to the supporting structure and to provide anchorage against lateral forces (such as wind) that may act on the panels.
The purpose of the air space is to provide a passage through which any water or moisture vapour that gets behind the cladding can be directed away from the building envelope before it infiltrates other parts of the building. Although caulking or other sealant materials are typically used to seal the spaces between cladding panels, the possibility of moisture infiltration behind the cladding—as a result of vapour migration, direct penetration of rainwater (due to sealant deterioration or other factors), or leakage at roof-to-wall junctures—cannot be entirely eliminated. If such moisture is not removed from the building envelope fairly promptly, it will tend to migrate further into the building, potentially causing a variety of problems that could entail costly maintenance and repairs and could detract from the building's overall durability and value. Such problems may include drywall damage due to moisture absorption, rot and mold in wooden construction components (e.g., studs and sheathing), corrosion of non-rust-resistant construction hardware, and staining on interior building finishes.
When an air space is provided behind the cladding, moisture can run downward behind the cladding to exit points such as weepholes built into the cladding system at appropriate locations. The air space also facilitates or enhances air circulation behind the cladding, helping to remove moisture vapour before it can condense inside the wall structure, and helping to dry out any wall structure components that may have become damp due to moisture infiltration.
One of the challenges facing designers of cladding panel support systems is to provide hangers or brackets that can adequately support weight of the panels at a distance away from the face of the supporting structure (i.e., so as to provide the desired air space), without significantly impeding the passage of water or water vapour through the air space. In this regard, it is particularly desirable to avoid or minimize hanger-to-panel connection details where moisture might become trapped or which might impede the downward vertical flow of moisture along the back of the panel. Depending on design preferences and panel manufacturing process constraints, hangers for precast cladding panels can be mechanically mounted to the panels after the panels have cured (such as by means of bolts, or by field-welding to mounting plates embedded in the panels), or they can be embedded into the panels during the panel-casting process.
It is desirable for precast cladding panels to be stackable as compactly as possible to minimize space requirements during storage and shipping. Accordingly, it is desirable for precast cladding panels to be configured such that they can be stacked in a way that minimizes or substantially eliminates space between stacked cladding panels, thus minimizing storage space requirements.
For the foregoing reasons, there is a need for improved precast cladding panel systems and hanger systems that enable secure mounting of panels at a uniform distance away from a vertical supporting structure without introducing significant impediments to air flow and moisture flow through the air space thus created between the panels and the supporting structure. In addition, there is a need for improved cladding panel hangers that can be embedded in precast panels during the casting process and which, although protruding from the finished panels, do not significantly impede the ability to stack the panels with minimal if any space between adjacent panels in the stack. The present disclosure is directed to these needs.
The present disclosure teaches embodiments of a hanger adapted to be cast into a precast cladding panel and which facilitates mounting of the panel onto a wall or other supporting structure without need for additional mounting hardware except for fasteners such as screws or nails. The hanger is configured such that an air space will be created between the precast cladding and the supporting structure, with air circulation through the air space being facilitated by openings formed in the hanger.
Accordingly, in a first aspect the present disclosure teaches an elongate hanger for embedment in a precast cladding panel, wherein the hanger defines:
The first, second, and third angles may be obtuse angles.
The mounting band may have a plurality of fastener holes in a lower region of the mounting band. In preferred embodiments, the center-to-center spacing of adjacent fastener holes will not be greater than 1.50 inches, and in particularly preferred embodiments will be approximately 1.25 inches.
The anchorage band preferably defines a plurality of anchorage openings, which may be of any configuration including but not limited to rectangular and triangular. The anchorage band also may include corrugated portions.
The abutment band may incorporate one or more bendable tabs.
The mounting band may be provided with one or more holes for facilitating mounting of the hanger in formwork for a precast panel.
In a second aspect, the present disclosure teaches a precast panel having an inner face, an outer face, a top edge face, and a bottom edge face, and further having a hanger as described above, with its anchorage band embedded in an upper portion of the panel such that:
Embodiments in accordance with the present disclosure will now be described with reference to the accompanying Figures, in which numerical references denote like parts, and in which:
As shown in
As shown in
Fastener holes 115 in mounting band 110 may be spaced as necessary or desired to suit the requirements of particular cladding panel installations. In one embodiment particularly suitable for mounting cladding panels to supporting walls framed with vertical wood studs, fastener holes 115 may be spaced at regular intervals of 1.25 inches (or less). Because standard wood studs are 1.50 inches thick, a fastener hole spacing of 1.25 inches ensures that there will always be a fastener hole 115 available at each stud, regardless of the stud spacing.
As indicated by reference numbers 119 in
In preferred embodiments, anchorage band 140 defines a plurality of openings 145 to enhance the effectiveness of its anchorage into a precast panel, by allowing the fluid panel material (e.g., concrete or liquid stone) to flow through openings 145 during the casting process and thus create a mechanical interlock between anchorage band 140 and the cured panel material. Optionally (and as best seen in
As shown in
Another optional feature of hanger 100A is the provision of one or more bendable tabs 118 formed into abutment band 130. In their initial configuration, tabs 118 are oriented into the plane of ventilation band 120 (as shown in
As shown in
As shown in
Ventilation band 120, which is contiguous with mounting band 110, preferably will have a generally horizontal orientation when panel 50 is mounted to a vertical support structure 60 (such as a wall), and in preferred embodiments may have a downward tilt away from mounting band 110 so as to promote drainage of any condensation in air space 70 away from support structure 60 and toward the mounted assembly of panels 50.
A typical procedure for installing panels 50 having hangers 100 may be readily understood with reference to
Provided that hangers 100 have suitable structural strength and stiffness, the installation of fasteners F into support structure 60 will have the beneficial effect of urging the lower portions of the corresponding panels 50 inward toward support structure 60) and into lateral contact with abutment bands 130 of the hangers 100 below (as discussed above). This happens because the lateral forces acting on mounting band 110 (due to the installation of fasteners F) will induce a counter-clockwise moment (as viewed in
In addition to facilitating the inducement of a beneficial moment about upper longitudinal edges 112 of mounting bands 110 as described above, the fact that mounting bands 110 lie in a tilted plane extending downward and away from support structure 60 makes it possible to adjust the lateral position of the upper edges of panels 50 relative to support structure 60 by tightening or loosening fasteners F as necessary.
Exterior wood-framed walls are typically covered with plywood or other exterior sheathing, but in some cases exterior wood-framed walls may be left unsheathed. As well, although exterior wood-framed walls commonly have wood studs (or other vertical framing elements) at a maximum horizontal spacing of 16 inches, in some cases the studs may be spaced up to or more than 24 inches apart. Panel hangers 100 in accordance with the present disclosure can be adapted for mounting precast panels to virtually any sheathed stud wall regardless of the width of the panels.
However, a problem can arise in the case of unsheathed stud walls where the width of some or all of the cladding panels is less than the clear space between studs, since the length of hanger 100 for a given precast panel will typically correspond to approximately the width of that panel. In such cases, the situation may arise where a panel's width and its position in the cladding assembly are such that the panel does not overlap any stud, such that there is no stud available for installing a fastener F to mount the panel. Another situation that may arise is where the a panel overlaps only a single stud and can therefore be mounted with only a single fastener F, resulting in the panel being “wobbly” (which would typically be unsatisfactory).
As illustrated in
Clip 150 may be of any functionally-effective configuration, but in the illustrated embodiment it is essentially a folded plate having a “hairpin” cross-sectional profile, comprising a pair of side plates 152 extending between an upper folded edge 156 and lower edges 154, and defining a gap 158 between side plates 152. Preferably, the width of gap 158 will closely correspond to the thickness of mounting bands 110 of hangers 100 onto which clip 150 is to be mounted, and may in fact be slightly less than the mounting band thickness so that clip 150 will be retained on mounting bands 110 by a friction fit, or by a clamping effect induced by elastic bending of clip 150 as gap 158 is forced to widen to receive mounting bands 110 (i.e., if the thickness of mounting bands 110 is greater than gap 158). Alternatively or in addition, clip 150 may be connected to mounting bands 110 using sheet metal screws or other suitable fasteners to enhance structural continuity between the panel hangers 100 (or 100A) to which clip 150 is mounted.
The dimensions of clip 150 may be selected to suit the requirements of specific panel installations and the dimensions of specific panel hangers 100 (or 100A).
Panel hangers 100, 100A, and 100B (and hanger clips 150) in accordance with the present disclosure may be fabricated from metal plate or sheet metal of appropriate thickness and structural properties to suit expected service conditions for a given installation. The material used for hangers 100, 100A, and 100B (and hanger clips 150) could be galvanized steel or another corrosion-resistant metal. However, the material used to fabricate hangers in accordance with the present disclosure is not restricted to metallic materials, and in alternative embodiments could be fabricated from a suitable plastic material. Hangers 100, 100A, and 100B preferably will be of unitary construction, but this is not essential; in alternative embodiments the hangers could be made up from multiple components or pieces joined together by suitable means.
Although hangers 100A and 100B are shown as having fastener holes 115 in mounting band 110, this is not essential to all embodiments of hangers within the scope of the present disclosure. Alternative embodiments could be fabricated without fastener holes in the mounting band (such as in hanger 100 in
It will be readily appreciated by those skilled in the art that various modifications to embodiments in accordance with the present disclosure may be devised without departing from the present teachings, including modifications that may use structures or materials later conceived or developed. It is to be especially understood that the scope of the present disclosure and claims should not be limited to or by any particular embodiments described, illustrated, and/or claimed herein, but should be given the broadest interpretation consistent with the disclosure as a whole. It is also to be understood that the substitution of a variant of a described or claimed element or feature, without any substantial resultant change in functionality, will not constitute a departure from the scope of the disclosure or claims.
In this patent document, any form of the word “comprise” is intended to be understood in a non-limiting sense, meaning that any element or feature following such word is included, but elements or features not specifically mentioned are not excluded. A reference to an element or feature by the indefinite article “a” does not exclude the possibility that more than one such element or feature is present, unless the context clearly requires that there be one and only one such element or feature. Any use of any form of any term describing an interaction between recited elements is not meant to limit the interaction to direct interaction between the elements in question, but may also extend to indirect interaction between the elements such as through secondary or intermediary structure.
Relational terms such as but not limited to “vertical”, “horizontal”, “parallel”, “uniform”, “planar”, and “coplanar”, are not intended to denote or require absolute mathematical or geometrical precision. Accordingly, such terms are to be understood as denoting or requiring substantial precision only (e.g., “substantially horizontal” or “generally parallel”) unless the context clearly requires otherwise. Any use of any form of the term “typical” is to be interpreted in the sense of being representative of common usage or practice, and is not to be interpreted as implying essentiality or invariability.
| Number | Date | Country | |
|---|---|---|---|
| 62437346 | Dec 2016 | US |
