Welded Wire Lath

Abstract

A welded wire mesh for use in securing stucco, plaster or other exterior finishing material to a building wall or other structure wherein the mesh comprises a matrix of longitudinally and transversely extending wires. The wires define intersections where the transversely extending wires are welded to the transversely extending wires and a plurality of deformations are formed in at least a portion of the wires between the intersections. The deformations cooperate with the stucco, plaster or other exterior finishing material to define a mechanical locking keys therebetween. The mesh can be disposed adjacent a flexible backing for providing a water vapor barrier, fire retardant or other desired property to the lath.

Description

BACKGROUND OF THE INVENTION

The present invention relates to an improvement in welded metal wire mesh for enabling stucco, plaster or other exterior finishing materials to bond to the surface of building walls or other structures. Welded wire mesh provides a strong mechanical securement key for the stucco, plaster or other exterior material that would not otherwise be provided by the wall surface. The use of welded wire mesh or lath for such purposes is well known. Typically, such products are formed of a matrix of smooth, longitudinal and transverse wires defining a plurality of squares or rectangles. The wires are welded together at the intersections of the horizontal and transverse wires to provide a strong, durable mesh that can be used as a stand alone product secured to the surface to which the stucco, plaster or other material is to be applied or, more commonly, with a moisture barrier backing sheet. In the latter configuration, the wire mesh can be secured to the backing in a variety of ways, including the use of a mechanical locking system in which the backing is comprised of a sheet of uncoated haft paper and a sheet of building paper or other material providing the moisture barrier that is bonded to the kraft paper. During fabrication, the longitudinal or horizontal wires of the mesh are sandwiched between the two backing sheets. The vertical wires that traverse the horizontal wires are disposed in front of the haft paper. Elongated perforations are provided in the haft paper to expose portions of the horizontal wires so that the vertical wires can be welded to the horizontal wires at their points of intersection to mechanically couple the paper/rectangular wire lath composite. The present invention is directed to improving the mechanical keying of the stucco or other building material to the welded wire mesh or lath and thereby enhancing the securement of stucco or other material to the building wall without significantly impacting the cost of the lath or its ease of use.

SUMMARY OF THE INVENTION

Briefly, the present invention comprises an improved welded wire mesh for use in a wire mesh lath for enhancing the securement of stucco, plaster and other exterior finishing materials to a building wall or other surface. The enhanced securement is obtained by providing deformations in the wire comprising the mesh, thereby creating a mechanical interference fit between the wire mesh and the stucco, plaster or other material adjacent each deformation in the mesh as the material hardens about the wire mesh. The deformations in the wire, can be formed by flattening longitudinally spaced portions along the otherwise smooth cylindrical wire, preferably, but not necessarily, on opposed sides of each wire. The deformations can be preformed in the wire or imparted to the wire during the construction of the lath, preferably prior to the welding together of the intersecting wires. The mesh can be disposed adjacent to a flexible backing for providing a water vapor barrier, fire retardant and/or other desired property to the lath.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a frontal plan view of a welded wire mesh lath comprising the present invention.

FIG. 2 is a frontal plan view of paper-backed welded wire mesh lath embodying the present invention.

FIG. 3A is an enlarged perspective view of a portion of a wire employed in the mesh of the present invention illustrating an example of deformations therein in accordance with the present invention formed therein.

FIG. 3B is an enlarged side view of a portion of a wire employed in the mesh of the present invention illustrating an example of deformations therein in accordance with the present invention formed therein.

FIG. 4 is a cross-sectional view taken along the line 4-4 in FIG. 3A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now in detail to the drawings, an example of welded wire mesh lath employing the present invention is illustrated in FIG. 1. The lath 10 illustrated therein comprises a plurality of vertically spaced horizontally extending wires 12 and a plurality of laterally spaced vertically extending wires 14 traversing wires 12 at intersections 16. Defoe nations 18 in the form of flattened surfaces are provided in a spaced disposition along wires 12 and 14. Wires 12 and 14 are welded together at intersections 16 to define the welded wire reinforcing mesh or lath 10. So configured, the lath 10 can be readily secured to a building wall or other structure, slightly proud of the outer surface thereof, to provide an enhanced mechanical keying of the wire, adjacent the deformations 18 therein, with the stucco, plaster or other exterior surface material as the material hardens about the wire mesh. The mesh is typically positioned such that it is about half way through the thickness of the stucco or other material. This is accomplished by the use of furring nails or in some cases a portion of the wire is bent to form a “stand off.” The enhanced keying effect results from the irregularities in the wire surfaces at the transitions 20 between the smooth outer surfaces and deformed areas in the wire that abut the hardened stucco or other material. As a result of this enhanced keying, a more secure coverage of the building wall or other structure is obtained.

In the embodiment of the invention illustrated in FIGS. 1 and 2, self-furred, zinc coated 0.51 in. nominal diameter wire, cylindrical in cross-section, is employed for both wires 12 and 14 at 1.5 inch vertical and horizontal spacings. The wires 12 and 14, however, can be formed of any desired ferrous or non-metallic material including, bright, galvanized, plated or coated iron, carbon or alloyed steel or from aluminum, stainless steel or brass and the spacing between the wires can be varied. Also, both the horizontal and vertical wires 12 and 14 are provided with spaced deformations 18 on opposed sides thereof to define interference fits between the mesh 10 and the stucco or other building material (not shown). It is to be understood, however, that, if desired, the deformations could be formed in only the horizontal wires 12 or only in vertical wires 14 and/or at different locations along the wire. Also, while longitudinally spaced deformations in the form of flattened areas are preferably provided along the wires, other deformity configurations could be provided in the wires to provide the desired interference fits with the stucco, plaster or other building material. Further, the deformations could be pre-formed in the wire or formed therein during or after the formation of the wires 12 and 14 into the desired matrix pattern, but preferably, prior to the welding together of the vertical and horizontal wires.

A second embodiment of welded metal wire mesh or lath 100 is illustrated in FIG. 2. This embodiment differs from the prior embodiment in that it employs a conventional backing 115 disposed about the plurality of welded horizontal wires 120 and vertical wires 140. In this embodiment, the mesh 100 can be identical to mesh 10 of the prior embodiment. The backing 115 can be of a composite configuration comprised of, for example, a rearwardly disposed water vapor permeable sheet 160 made of, for example, asphalt paper, known as black paper, and a front sheet 165 of separator paper, such as kraft paper, having a plurality of rows of elongated perforations 170 formed therein. The wire mesh 100 can be sandwiched between the rear and forward sheets 165 and 170 which can be secured together by a suitable adhesive (not shown) such that the intersections 116 of the horizontal and vertical wires 120 and 140 are disposed within perforations 170 to provide access to the intersections for the welding together of the wires, thereby securing together the wire mesh 100 and the composite backing 115 to form the lath 100. In this second embodiment, the horizontal wires 120 and vertical wires 140 can be formed of the same materials as wires 12 and 14 of the prior embodiment and can be spaced apart distances ranging from about one to two inches. In the embodiment of FIGS. 3 and 4, the deformations 180 are preferably preformed in the wires to facilitate construction but could be formed during construction, as with the stand alone mesh 10 of the prior embodiment. The deformations 180 in the wires 120 and 140 also could vary in size, shape and location as in the prior embodiment. Different backings 115 could be employed to add additional or different properties to the lath, such as a sheet of a fire retardant material.

Various changes and modifications can be made in carrying out the present invention without departing from the spirit and scope thereof. Insofar as these changes and modifications are within the purview of the appended claims, they are to be considered as part of the present invention.

Claims

1. A welded wire mesh for use in securing an exterior finishing material to a building wall or other structure as the material dries about and bonds to the wire mesh, said mesh comprising a matrix of longitudinally and transversely extending wires, said wires defining intersections, said longitudinally extending wires being welded to said transversely extending wires at said intersections, and a plurality of spaced surface deformations formed in at least a portion of said longitudinally and/or transversely extending wires between said intersections, said surface deformations defining variations in the cross-sectional configuration of said wires between said intersections and cooperating with the exterior finishing material to define a plurality of mechanical locking keys therebetween.

2. The wire mesh of claim 1 wherein said longitudinally and transversely extending wires are cylindrical in cross-section and said deformations define intermittent flattened surfaces in said wire between cylindrical portions of said wire and wherein the juncture of said flattened and cylindrical portions of said wire comprise said mechanical locking keys with the finishing material.

3. A welded wire lath structure for use in securing an exterior finishing materials to a building wall or other structure as the material dries about and bonds to the wire mesh, said lath structure comprising a backing and a matrix of longitudinally and transversely extending wires secured to said backing, said wires comprising a matrix of longitudinally and transversely extending wires, said wires defining intersections, said longitudinally extending wires being welded to said transversely extending wires at said intersections, and a plurality of spaced surface deformations formed in at least a portion of said longitudinally and/or transversely extending wires between said intersections, said surface deformations defining variations in the cross-sectional configuration of said wires between said intersections and cooperating with the exterior finishing material to define a plurality of mechanical locking keys therebetween.

4. The lath of claim 3 wherein said longitudinally and transversely extending wires are cylindrical in cross-section and said deformations define intermittent flattened surfaces in said wire between cylindrical portions of said wire and wherein the juncture of said flattened and cylindrical portions of said wire comprise said mechanical locking keys with the finishing material.

5. The lath of claim 4 wherein said sheet of backing material defines a water vapor barrier for said lath.