Thermally coated wall anchor and anchoring systems with in-cavity thermal breaks for cavity walls

Abstract

Thermally-isolating wall anchors and reinforcement devices and anchoring systems employing the same are disclosed for use in masonry cavity walls. A thermally-isolating coating is applied to the wall anchor, which is interconnected with a wire formative veneer tie. The thermally-isolating coating is selected from a distinct grouping of materials, that are applied using a specific variety of methods, in one or more layers and cured and cross-linked to provide high-strength adhesion. The thermally-coated wall anchors provide an in-cavity thermal break that severs the thermal threads running throughout the cavity wall structure, reducing the U- and K-values of the anchoring system by thermally-isolating the metal components.

Claims

1. A wall anchor for use in a cavity wall having an outer wythe and an inner wythe in a spaced apart relationship and forming a cavity therebetween, the wall anchor comprising: one or more leg portions configured to extend into the cavity and formed from wire formative; a veneer tie receptor portion contiguous with the one or more leg portions, the veneer tie receptor portion formed from wire formative and configured to engage a veneer tie mounted in the outer wythe; and a thermally-isolating coating disposed on the veneer tie receptor portion and retained with the veneer tie receptor portion prior to installation of the wall anchor in the cavity wall, the coating being selected to have low thermal conductivity and transmissivity, the coating forming a thermal break in the cavity; wherein upon installation in the cavity wall, the wall anchor restricts thermal transfer between the veneer tie and the wall anchor and between the wall anchor and the veneer tie.

2. The wall anchor of claim 1, wherein the veneer tie receptor portion and the one or more leg portions are made from mill galvanized, hot galvanized, or stainless steel.

3. The wall anchor of claim 2, wherein the one or more leg portions is free from thermal coating.

4. The wall anchor of claim 2, wherein the thermally-isolating coating is disposed on only the veneer tie receptor portion.

5. The wall anchor of claim 2, wherein the thermally-isolating coating is disposed on the one or more leg portions.

6. The wall anchor of claim 2, wherein the veneer tie receptor portion comprises an eyelet defined by an interior surface of the receptor portion, the thermally-isolating coating being disposed on the interior surface defining the eyelet.

7. The wall anchor of claim 6, wherein at least parts of the interior surface of the receptor portion are in opposed relation with each other.

8. The wall anchor of claim 6, wherein the wall anchor comprises two leg portions extending into the cavity and the veneer tie receptor portion eyelet interconnects the two leg portions.

9. The wall anchor of claim 1, wherein the one or more leg portions is free from thermal coating.

10. The wall anchor of claim 1, wherein the thermally-isolating coating is disposed on only the veneer tie receptor portion.

11. The wall anchor of claim 1, wherein the thermally-isolating coating is disposed on the one or more leg portions.

12. The wall anchor of claim 1, wherein said one or more leg portions comprises two leg portions extending into the cavity and a rear leg extending between the two leg portions.

13. The wall anchor of claim 12, wherein the thermally-isolating coating is further applied to the leg portions and the rear leg.

14. The wall anchor of claim 1, wherein the veneer tie receptor portion comprises an eyelet defined by an interior surface of the receptor portion, the thermally-isolating coating being disposed on the interior surface defining the eyelet.

15. The wall anchor of claim 14, wherein the wall anchor comprises two leg portions extending into the cavity and the veneer tie receptor portion eyelet interconnects the two leg portions.

16. The wall anchor of claim 1, wherein the thermally-isolating coating is one or more layers of a compound selected from the group consisting of thermoplastics, thermosets, natural fibers, rubbers, resins, asphalts, ethylene propylene diene monomers, and admixtures thereof.

17. The wall anchor of claim 16, wherein the selected compound is an isotropic polymer selected from the group consisting of acrylics, nylons, epoxies, silicones, polyesters, polyvinyl chlorides, and chlorosulfonated polyethylenes.

18. The wall anchor of claim 16, wherein the thermally-isolating coating includes a prime coat; and wherein outer layers of the thermally-isolating coating are cross-linked to the prime coat to provide high-strength adhesion to the wall anchor cavity portion.

19. The wall anchor of claim 16, wherein the thermally-isolating coating reduces the K-value of the wall anchor to a level not to exceed 1.0 W/m.sup.2K.

20. The wall anchor of claim 16, wherein the thermally-isolating coating reduces the U-value of the wall anchor to a level not to exceed 0.35 W/m.sup.2K.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following drawings, the same parts in the various views are afforded the same reference designators.

(2) FIG. 1 shows a perspective view of this invention with an anchoring system having a thermally isolating wall anchor, as applied to a cavity wall with an inner wythe of masonry construction with insulation disposed on the cavity-side thereof and an outer wythe of brick interconnected with a veneer tie and a reinforcement wire;

(3) FIG. 2 is a perspective view of an alternative anchoring system with a truss reinforcement with an anchor without a rear leg interconnected with a veneer tie;

(4) FIG. 3 is a perspective view of another alternative design thermally-isolating anchoring system interconnected with a veneer tie set on a masonry cavity wall;

(5) FIG. 4 is a perspective view of another alternative design thermally-isolating wall anchoring system for emplacement within a cavity wall, the anchoring system is interconnected with a veneer tie and reinforcement wire;

(6) FIG. 5 is a perspective view of a cross-section of the thermally-isolating wall anchor of FIG. 4 showing the wire formative wall anchor with the thermally-isolating coating applied thereon;

(7) FIG. 6 is a side view of a cross-section of the thermally-isolating wall anchor of FIG. 2 showing the wire formative wall anchor with the thermally-isolating coating applied to the veneer tie receptor portion; and,

(8) FIG. 7 is a cross-sectional view of the leg portion of the wall anchor of FIG. 5 with the thermally-isolating coating applied thereon.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(9) Before entering into the detailed Description of the Preferred Embodiments, several terms which will be revisited later are defined. These terms are relevant to discussions of innovations introduced by the improvements of this disclosure that overcome the technical shortcoming of the prior art devices.

(10) In the embodiments described hereinbelow, the inner wythe is optionally provided with insulation and/or a waterproofing membrane. In the cavity wall construction shown in the embodiments hereof, this takes the form of exterior insulation disposed on the outer surface of the inner wythe. Recently, building codes have required that after the anchoring system is installed and, prior to the inner wythe being closed up, that an inspection be made for insulation integrity to ensure that the insulation prevents infiltration of air and moisture. Here the term insulation integrity is used in the same sense as the building code in that, after the installation of the anchoring system, there is no change or interference with the insulative properties and concomitantly substantially no change in the air and moisture infiltration characteristics.

(11) In a related sense, prior art wire formative anchors and anchoring systems have formed a conductive bridge between the wall cavity and the interior of the building. Here the terms thermal conductivity and thermal conductivity analysis are used to examine this phenomenon and the metal-to-metal contacts across the inner wythe. The present anchoring system serves to sever the conductive bridge and interrupt the thermal pathway created throughout the cavity wall by the metal components, including a reinforcement wire which provides a seismic structure. Failure to isolate the metal components of the anchoring system and break the thermal transfer, results in heating and cooling losses and in potentially damaging condensation buildup within the cavity wall structure.

(12) In the detailed description, the wall anchor and reinforcement and the veneer ties and reinforcement wires are wire formatives. The wire used in the fabrication of veneer joint reinforcement conforms to the requirements of ASTM Standard Specification A951-00, Table 1. For the purpose of this application tensile strength tests and yield tests of veneer joint reinforcements are, where applicable, those denominated in ASTM A-951-00 Standard Specification for Masonry Joint Reinforcement.

(13) The thermal stability within the cavity wall maintains the internal temperature of the cavity wall within a certain interval. Through the use of the presently described thermally-isolating coating, the underlying metal wire formative wall anchor, obtains a lower transmission (U-value) and thermal conductive value (K-value), providing a high strength anchor with the benefits of thermal isolation. The term K-value is used to describe the measure of heat conductivity of a particular material, i.e., the measure of the amount of heat, in BTUs per hour, that will be transmitted through one square foot of material that is one inch thick to cause a temperature change of one degree Fahrenheit from one side of the material to the other. The lower the K-value, the better the performance of the material as an insulator. The metal wire comprising the components of the anchoring systems generally have a K-value range of 16 to 116 W/m K. The thermal coating disposed on the wall anchor of this invention greatly reduces such K-values to a low thermal conductive (K-value) not to exceed 1 W/m K. Similar to the K-value, a low thermal transmission value (U-value) is important to the thermal integrity of the cavity wall. The term U-value is used to describe a measure of heat loss in a building component. It can also be referred to as an overall heat transfer co-efficient and measures how well parts of a building transfer heat. The higher the U-value, the worse the thermal performance of the building envelope. Low thermal transmission or U-value is defined as not to exceed 0.35 W/m.sup.2K for walls. The U-value is calculated from the reciprocal of the combined thermal resistances of the materials in the cavity wall, taking into account the effect of thermal bridges, air gaps and fixings.

(14) Referring now to FIGS. 1 through 7, the present invention shows an anchoring system with a thermally isolating wall anchor that provides an in-cavity thermal break. This system is suitable for recently promulgated standards and, in addition, has lower thermal transmission and conductivity values than the prior art anchoring systems. The system discussed in detail hereinbelow, has a thermally-isolating wall anchor and reinforcement device with a veneer tie receptor portion for interengagement with a veneer tie. The reinforcement device is mounted in the bed joint of the inner wythe. Where insulation is shown on the (FIG. 1), a cavity wall having an insulative layer of 2.5 inches (approx.) and a total span of 3.5 inches (approx.) is chosen as exemplary.

(15) The thermally-isolating anchoring system for cavity walls is referred to generally by the numeral 10. A cavity wall structure 12 is shown having an inner wythe or backup wall 14 of successive courses of masonry block 16 with mortar-filled bed joints 22 of a predetermined height between each adjacent course 16 and an outer wythe or facing wall 18 of brick 20 construction. Between the inner wythe 14 and the outer wythe 18, a cavity 23 is formed. The inner wythe 14 has optional attached insulation 26.

(16) Successive bed joints 30 in the outer wythe 18 and bed joints 22 in the inner wythe 14 are substantially planar and horizontally disposed and in accord with building standards are a predetermined 0.375-inch (approx.) in height. Selective ones of bed joints 30, which are formed between courses of bricks 20, are constructed to receive therewithin the insertion portion 68 of the veneer tie 44 of the anchoring system hereof. Selective ones of bed joints 22, which are formed between courses of masonry block 16, are constructed to receive therewithin the wall reinforcement 46 of the anchoring system hereof. The wall reinforcement 46 is constructed from a pair of side wires 50, 52 disposed parallel to each other. The pair of side wires 50, 52 each have a longitudinal axis 17. Intermediate wires 54 are affixed to the interior sides 56, 58 of the side wires 50, 52 configuring the wall reinforcement 46 in either a truss (FIGS. 1 and 2) or a ladder formation (FIGS. 3 and 4). The intermediate wires 54 have longitudinal axes 19 and when the wall reinforcement 46 is mounted within the inner wythe 14, the longitudinal axes 17 and 19 are disposed in a substantially horizontal plane.

(17) For purposes of discussion, the cavity surface 24 of the inner wythe 14 contains a horizontal line or x-axis 34 and an intersecting vertical line or y-axis 36. A horizontal line or z-axis 38, normal to the xy-plane, passes through the coordinate origin formed by the intersecting x- and y-axes. As shown in FIG. 1, thermally-isolating wall anchors 40 are constructed from a wire formative. Alternative design wall anchors 40 are shown in FIGS. 2 and 3. The wall anchor 40 is fusibly attached to the wall reinforcement 46 either along the side wire 50 or on the side wire 50 and intermediate wires 54. The wall anchor 40 has leg portions 62, which are optionally interconnected by a rear leg 63, that extend toward and into the cavity 23. A veneer tie receptor portion 64 is contiguous with the leg portion 62 and configured to interengage a veneer tie 44. The veneer tie receptor portion takes varied forms and is shown as an eyelet 80 with a predetermined diameter to interengages with the veneer tie 44 interengaging end portion 90 in FIGS. 1, 4, and 5 and an elongated eyelet in FIGS. 2 and 6. The eyelet 80 is optionally welded closed. A further variation is of the wall anchor 40 shown in FIG. 3. This variation has a single eyelet 80 that interconnects the leg portions 62 per QS.

(18) A thermally-isolating coating or thermal coating 85 is applied to the veneer tie receptor portion 64 (as shown in FIG. 6) to provide a thermal break in the cavity. The thermal coating 85 is optionally applied to the leg portions 62 and the rear leg 63 (as shown in FIG. 5) to provide ease of coating and additional thermal protection. The thermal coating 85 is selected from thermoplastics, thermosets, natural fibers, rubbers, resins, asphalts, ethylene propylene diene monomers, and admixtures thereof and applied in layers. The thermal coating 85 optionally contains an isotropic polymer which includes, but is not limited to, acrylics, nylons, epoxies, silicones, polyesters, polyvinyl chlorides, and chlorosulfonated polyethelenes. The initial layer of the thermal coating 85 is cured to provide a precoat and the layers of the thermal coating 85 are cross-linked to provide high-strength adhesion to the veneer tie to resist chipping or wearing of the thermal coating 85.

(19) The thermal coating 85 reduces the K-value and the U-value of the underlying metal components which include, but are not limited to, mill galvanized, hot galvanized, and stainless steel. Such components have K-values that range from 16 to 116 W/m K. The thermal coating 85 reduces the K-value of the veneer tie 44 to not exceed 1.0 W/m K and the associated U-value to not exceed 0.35 W/m.sup.2K. The thermal coating 85 is not combustible and gives off no toxic smoke in the event of a fire. Additionally, the thermal coating 85 provides corrosion protection which protects against deterioration of the anchoring system 10 over time.

(20) The thermal coating 85 is applied through any number of methods including fluidized bed production, thermal spraying, hot dip processing, heat-assisted fluid coating, or extrusion, and includes both powder and fluid coating to form a reasonably uniform coating. A coating 85 having a thickness of at least about 5 micrometers is optimally applied. The thermal coating 85 is applied in layers in a manner that provides strong adhesion to the wall anchor 40. The thermal coating 85 is cured to achieve good cross-linking of the layers. Appropriate examples of the nature of the coating and application process are set forth in U.S. Pat. Nos. 6,284,311 and 6,612,343.

(21) The veneer tie 44 is a wire formative generally with a pintle design and shown in FIGS. 1 and 3 as being emplaced on a course of bricks 20 in preparation for embedment in the mortar of bed joint 30. The thermally-isolating anchoring system 10 includes a wall anchor 40, a reinforcement device 46, a veneer tie 44, and optionally a reinforcement wire 71.

(22) The dimensional relationship between wall anchor 40 and veneer tie 44 limits the axial movement of the construct. The veneer tie 44 is a wire formative. Each veneer tie 44 has an interengaging end portion 90 which is in close fitting functional relationship with the diameter of the veneer tie receptor portion 64 and an insertion portion 68 for insertion within the outer wythe 14. The veneer tie receptor portion 64 is constructed, in accordance with the building code requirements, to be within the predetermined dimensions to limit the z-axis 38 movement and permit y-axis 36 adjustment of the veneer tie 44. The dimensional relationship of the interengaging end portion 80 to the veneer tie receptor portion 64 limits the x-axis movement of the construct.

(23) The insertion portion 68 is optionally (FIG. 3) compressively reduced in height to a combined height substantially less than the predetermined height of the bed joint 30 ensuring a secure hold in the bed joint 30 and an increase in the strength and pullout resistance of the veneer tie 44. Further to provide for a seismic construct, an optional compression or swaged indentation 69 is provided in the insertion portion 68 to interlock in a snap-fit relationship with a reinforcement wire 71 (as shown in FIG. 4).

(24) As shown in the description and drawings, the present invention serves to thermally isolate the components of the anchoring system reducing the thermal transmission and conductivity values of the anchoring system to low levels. The novel coating provides an insulating effect that is high-strength and provides an in-cavity thermal break, severing the thermal threads created from the interlocking anchoring system components.

(25) In the above description of the anchoring systems of this invention various configurations are described and applications thereof in corresponding anchoring systems are provided. Because many varying and different embodiments may be made within the scope of the inventive concept herein taught, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirement of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.