This invention relates to building systems which use fiber reinforced polymeric. (FRP) construction panels to make structural walls and wall systems as primary support structures in buildings. Such reinforced construction panels largely replace concrete, for example ready-mix concrete, pre-fabricated concrete blocks, other pre-fabricated concrete products, or wood, or steel, or other conventional wall structure materials, in construction projects. In general, the invention replaces concrete in e.g. below-grade frost walls and foundation walls; can replace either concrete or wood or steel in above-grade walls. Thus, in the invention, structures based on resin-impregnated, fiber-based layers, as composite materials, also known as fiber-reinforced polymer materials (FRP) replace such conventional materials and structures. Structures of the invention typically include thermally insulating foam, and optionally include regularly-spaced “studs”, as part of a wall panel.
Any construction materials used to enclose inhabited living space are subject to fire safety codes. For example, for residential construction, the inside surface of a wall containing insulating foam must satisfy certain fire rating tests such as e.g. ASTM E119, or UL 1715, or NFPA 286.
There is a need, in the construction industry, for relatively light weight, e.g. FRP, structural construction panels which satisfy such fire test requirements.
Where a panel, itself, or the collective components which make up the panel, do not meet fire code/fire rating test requirements, the panel can still be used, but with the remedial step of installing, on that side of the panel which faces the inhabited living space, drywall or other material which does satisfy the fire rating tests. In such instance, typically the panel is first furred out with. e.g. 2×4, 2×6 wood or steel studs, creating utility run channels inwardly of the panel and then adding a layer of drywall or other sheet material which meets the fire rating requirements, over the studs, thus enclosing the utility run channels between the panels and the drywall. Such furring takes up valuable interior space inside the building as well as adding to the cost, and time, needed for construction of the building.
There is thus a need for a stand-alone relatively light weight FRP construction panel which can satisfy the appropriate fire-rating test(s) without requiring remedial addition of any material between the panel and the inhabited living space.
There is yet further a need for such construction panels where the exposed major surfaces of the panels are largely polymeric whereby a wide range of attachment options and decoration options are available.
These and other needs are alleviated, or at least attenuated, or partially or completely satisfied, by the novel articles and methods of the invention.
This invention provides construction panels, and methods of making construction panels for a building system which provides wall, ceiling, and/or floor building panels and corresponding walls and wall sections, ceilings and ceiling sections, and floors and floor sections. The walls, taken in a vertical orientation, have both vertical compression-resistance strength, and horizontal bending-resistance strength, sufficient that the wall system can be used in below-ground building structural applications, as well as above-ground applications, including applications where such wall systems are exposed to severe wind and other weather, such as hurricanes, tornadoes, and the like as well as meeting all current United States of America fire-test requirements for panels devoid of any drywall covering. Construction panels of the invention, and corresponding walls, can replace concrete, meeting required strength specifications for use in single family residential, commercial, and industrial applications.
A construction panel of the invention has an outer fiber-reinforced polymeric layer, and an inner fiber-reinforced polymeric layer. One or more structurally-reinforcing members can extend the full height of the erected construction panel, and can extend from locations at or proximate the inner surface of the outer layer to locations at or proximate the inner surface of the wall structure, at spaced locations along the length of the construction panel. Thermally insulating foam, generally occupies, fills, that space, which is not otherwise occupied, between the inner and outer layers. A fire-rated capacity is provided by a fire-rated board product, rated to pass at least a 15-minute fire test, incorporated as part of the finally-completed panel. Such fire-rated board can be foam-based, or non-foam-based. The fire-rated board product, whether a foam-based product or a non-foam-based product, can be enclosed in the panel between the inner and outer layers. Where the board is non-foam-based, the fire-rated board can be disposed, as part of the panel, as one or both outer surfaces of the panel structure, optionally between studs which protrude from the inner layer. Where the fire-rated board is a foam-based product, the fire-rated board can be the thermally insulating foam which generally occupies, fills the space which is not otherwise occupied between the inner and outer layers.
Taken in an upright orientation, the construction panel has a top, a bottom, opposing ends, a length between the ends, a height between the top and the bottom, and a thickness between the inner and outer surfaces of the panel.
The inner layer, the outer layer, and the reinforcing members are typically all part of a unitary fiber-reinforced resinous structure. But in some embodiments, the reinforcing members are omitted, whereby the inner and outer layers represent separate fiber-reinforced resinous structures on opposing sides of the foam.
The structurally-reinforcing members may be integral with the inner and outer layers, whereby the structurally-reinforcing members extend between the inner and outer layers, and thus function in a capacity similar to the web of an I-beam, and associated portions of the thus—integral/unitary inner and outer layers function in capacities similar to the functioning of flanges of such I-beam.
In some embodiments, the fire-rated capacity is provided by a first such fire-rated board, disposed on the interior of the panel between the foam and the inner layer, and a second such fire-rated board is optionally disposed on the interior of the panel between the foam and the outer layer.
In some embodiments, the fire-rated board is disposed outwardly of the inner layer such that the inner layer is between the fire-rated board and the foam, and optionally a second fire-rated board is disposed outwardly of the outer layer such that the outer layer is between the fire-rated board and the foam.
In some embodiments, the fire rating capability is provided by using, as the thermally insulating foam, between the inner and outer layers, a foam product which has, separate from the construction panel, achieved a passing rating in an appropriate fire-rating test.
In some embodiments, a plurality of studs are spaced from each other on the inner surface of the panel, protruding from the inner layer. A stud can originate at either the inner layer or the outer layer. Such studs typically comprise first and second legs, spaded from each other and extending from the inner layer to an end panel. Such studs can be integral members of the panel, or can be mounted onto the panel after primary fabrication of the panel has been completed.
In some embodiments, one of the stud legs, on a given stud, overlies one of the reinforcing members, such that the stud leg acts as an extension of the reinforcing member and thereby functions as though that leg had originated at or proximate the outer layer.
In a first family of embodiments, the invention comprehends a construction panel, comprising an outer side of the construction panel, configured to be used as an outward-facing side on a building, such outer side comprising an outer fiber-reinforced polymeric layer proximate or at a first outermost surface of the construction panel; an inner side of the construction panel configured to be used as an inward-facing side on such building, such inner side comprising an inner fiber-reinforced polymeric layer proximate or at a second opposing outermost surface of the construction panel; the construction panel having a height defined between a top and a bottom of the construction panel when the construction panel is in an upright use orientation, the construction panel further having a length, and a thickness between the outer side and the inner side, thermally insulating foam between the inner layer and the outer layer, the thermally insulating foam extending between the top of the construction panel and the bottom of the construction panel; and at least one of (i) a layer of at least 15-minute fire-rated board extending the full height and substantially the full length of the construction panel between the inner layer and the outer layer and (ii) as the thermally insulating foam, a fire-rated foam which has, separate from the construction panel, achieved a passing rating in an appropriate fire-rating test, the construction panel having a thermal insulation rating of at least R8, and a vertical crush strength of at least about 3000 pounds per linear foot (4463 kg per meter) of the construction panel.
In some embodiments, the fire-rating capacity is provided by such layer of fire-rated board, having at least a 15-minute fire rating, disposed between the thermally insulating foam and at least one of the inner layer and the outer layer.
In some embodiments, the thermally insulating foam comprises a plurality of elongate foam blocks extending along the height of the construction panel, the foam blocks having inner surfaces disposed toward the inward-facing side of the construction panel, outer surfaces facing toward the outward-facing side of the construction panel, and opposing side surfaces connecting the inner and outer surfaces, the inner, outer, and side surfaces of respective ones of the foam blocks defining perimeters of the respective foam blocks, the layer of fire-rated board being disposed between the inner surfaces of the foam blocks and the inner layer as separate board elements overlying respective ones of the foam blocks.
In some embodiments, the fire-rated board is omitted, and the fire-rating capacity is provided by using as the foam blocks, foam blocks which, themselves, have the requisite fire rating capacity, whereby no fire-rating testing of the respective construction panel is needed after completion of assembly of the panel because such fire-rated foam, in the panel: satisfies the requirements of fire-rating testing.
In some embodiments, fiber-reinforced polymeric wrapping layers extending about the perimeters of the foam blocks on at least the inner surfaces, separate such fire-rated board elements between the inner surfaces of the foam blocks and the wrapping layers.
In some embodiments, the wrapping layers extend across the opposing side surfaces of the foam blocks, the wrapping layers, at the side surfaces having lengths extending along the height of the construction panel, and depths extending along the thickness of the construction panel, the foam blocks being in abutting side-by-side relationship with each other, the construction panel further comprising a plurality of studs spaced along the length of the construction panel, the studs extending along the height of the construction panel, and extending away from the outer layer, a given stud having first and second legs spaced from each other, and extending to an end panel, the stud legs having lengths extending along the height of the construction panel and depths extending from the end panel to the outermost surface of the construction panel, one of the legs being aligned, along the length of the leg, with the depth of a respective wrapping layer, along the length of, and aligned with, the respective wrapping layer at a respective side of a corresponding one of the foam blocks, such that the respective leg of the stud acts as a depth extension of the respective wrapping layer at the respective side of the respective foam block and along the height of the construction panel.
In some embodiments, side edges of adjacent ones of the board elements are spaced from each other by gaps of at least about 0.05 inch (0.13 cm) at the side surfaces of the foam blocks.
In some embodiments, the panel comprises a plurality of studs spaced along the length of the construction panel, the studs extending along the height of the construction panel, and extending away from both the fire-rated component of the construction panel, and away from the outermost surface.
In some embodiments, the panel either comprises a layer of at least 15-minute fire-rated board extending about the studs or the foam board elements between the inner and outer layers have the requisite fire rating, themselves.
In some embodiments, fire-rated boards extending about the studs are disposed between fiber-reinforced polymeric layers on the studs and core structures of the studs.
In some embodiments, the panel further comprises a second layer of at least 15-minute fire-rated board extending the full height and substantially the full length of the construction panel between the outer layer and the thermally insulating foam.
In some embodiments, the second layer of fire-rated board is disposed between the outer surfaces of the foam blocks and the outer layer as separate board elements overlying respective ones of the foam blocks, optionally between the outer surfaces of the foam blocks and the wrapping layers.
In some embodiments, the core structures of the studs are, themselves, elongate fire-rated foam boards.
In some embodiments, the wrapping layers further extend across the side surfaces, and to the inner surfaces of the foam blocks, further comprising studs spaced along the length of the construction panel, and extending away from both the inner surfaces of the foam blocks and the outermost surface, a given stud having first and second legs spaced from each other, and extending to an end panel, the stud legs having lengths extending along the height of the construction panel and depths extending from the end panel to the second outermost surface of the construction panel, one of the legs being aligned, along the length of the leg, with the depth of a respective wrapping layer, along the length of the respective wrapping layer at a respective side of a corresponding one of the foam blocks, such that the respective leg of the stud acts as a depth extension of the respective wrapping layer at the respective side of the respective foam block and along the height of the construction panel.
In a second family of embodiments, the invention comprehends a construction panel, comprising an outer side of the construction panel, configured to be used as an outward-facing side on a building, such outer side comprising an outer fiber-reinforced polymeric layer proximate or at a first outermost surface of the construction panel; an inner side of the construction panel, configured to be used as an inward-facing side on such building, such inner side comprising an inner fiber-reinforced polymeric layer proximate or at a second opposing outermost surface of the construction panel; the construction panel having a height defined between a top and a bottom of the construction panel when the construction panel is in an upright use orientation, the construction panel further having a length, and a thickness between the outer side and the inner side, thermally insulating foam between the inner layer and the outer layer, the thermally insulating foam extending between the top of the construction panel and the bottom of the construction panel; a plurality of studs spaced along the length of the construction panel, the studs extending along the height of the construction panel, and extending away from both of the inner and outer layers; channels being defined between respective ones of the studs, a given channel extending on first and second opposing sides of the channel to adjacent ones of the studs, a third side of such channel extending across the second outermost surface, and such channel being open on a fourth side opposing the third side; and boards, having at least 15-minute fire ratings; extending the full height and substantially the full length of the construction panel in the respective channels at or proximate the second outermost surface, sides of the fire-rated boards being disposed proximate sides of respective ones of the studs, the construction panel having a thermal insulation rating of at least R8, and a vertical crush strength of at least about 3000 pounds per linear foot (4463 kg per meter) of the construction panel.
In some embodiments, the construction panel further comprises a second layer of the at least 15-minute fire-rated board extending the full height and substantially the full length, of the construction panel at or proximate the first outermost surface and outwardly of the outer layer.
In a third family of embodiments, the invention comprehends a construction panel, comprising an outer side of the construction panel, configured to be used as an outward-facing side on a building, the outer side comprising a first outermost fiber-reinforced polymeric layer; an inner side of the construction panel, configured -to be used as an inwardly-facing side on such building, the inner side comprising a second outermost fiber-reinforced polymeric layer, the construction panel having a height defined between, a top and a bottom of the construction panel when the construction panel is in an upright use orientation, the construction panel further having a length, and a thickness between the outer side and the inner side, the outer layer and the inner layer defining a panel body therebetween, thermally insulating foam between the inner layer and the outer layer, the thermally insulating foam extending between the top of the construction panel and the bottom of the construction panel; first and second boards, having at least 15-minute fire ratings, extending the full height and substantially the full length of the construction panel and overlying the respective outer and inner layers respectively so as to enclose substantially all of the panel body therebetween; and a plurality of studs on the inner side of the construction panel, and mounted to the second board, the studs being spaced along the length of the construction panel, the second board being disposed between the inner layer and the studs, the construction panel having a thermal insulation rating of at least R8, and a vertical crush strength of at least about 3000 pounds per linear foot (4463 kg per meter) of the construction panel.
The invention further comprehends a wall structure fabricated using a plurality of construction panels of the invention.
The invention is not limited in its application to the details of construction, or to the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various other ways. Also, it is to be understood that the terminology and phraseology employed herein is for purpose of description and illustration and should not be regarded as limiting. Like reference numerals are used to indicate like components.
Referring to
In the invention, a fire-rated board which protects a construction panel of the invention can be disposed as an interior layer on the interior of the panel, e.g. between the inner layer and the outer layer of the panel, or as an exterior layer defining at least a portion of the exterior surface of the panel.
Panel 10 also has an inner layer 18 which forms the inwardly-facing side 20 of the panel, namely that side of the panel which is intended to face inwardly, into the. interior of the building into which the panel is incorporated in the process of being used. The exposed surface of inner layer 18 defines a second outermost surface 22 of the panel, on the opposing side of the panel from first outermost surface 16.
A layer 24 of thermally insulating foam is disposed between outer layer 12 and inner layer 18. In the embodiment illustrated in
A fire-rated layer 26 is disposed between foam layer 24 and inner layer 18. In the embodiment illustrated in
Fire-rated layer 26 is selected for its ability to protect foam layer 24 for a period of time required by a respective fire code. In a common instance of residential codes, the fire code requires that the foam be protected from ignition, from a fire directed at the second outermost surface 22 of the panel, namely the surface facing the interior of the building, for a period of 15 minutes in a corner structure, known as the 15-minute corner fire test. In a common instance of commercial and industrial codes, the fire code requires that the foam be protected from ignition, from a fire directed at either or both of the first or second outermost surfaces of the panel, namely from the inner side of the panel or the outer side of the panel.
Examples of suitable test procedures which can be used to demonstrate satisfaction of the respective fire codes are ASTM E119, UL 1715, and/or NFPA 286.
A fire-rating standard commonly used for residential construction is UL 1715, which requires that any polymeric foam not respond inappropriately to fire for 15 minutes. UL 1715 can be met by providing a fire-protective barrier between such foam and the surface, of the panel which may be exposed to fire. UL 1715 is also met where any foam in the assembled e.g. panel meets the requirements of UL 1715, which means that the assembled panel meets the requirements of UL 1715 without specific testing of the assembled panel.
In the embodiment illustrated in
Outer layer 12 and inner layer 18 are fiber-reinforced polymeric layers. Namely the compositions of layers 12 and 18 are part fiber and part reaction-cured polymer.
A typical foam block is about 3 inches thick and about 8 inches wide. The three inch thickness provides three inches of thermal insulation value to that portion of the panel which is between the inner and outer layers. Using the 8-inch width, two or three such blocks span a portion of the length of the panel corresponding to the usual 16-inch or 24-inch spacing between studs where studs are used on the inner surface of a wall. Such cooperative spacing of blocks and studs is further illustrated hereinafter.
Each foam block 32 is surrounded by a fiber-reinforced polymeric wrapping layer 34. Outer fire-rated layer/board 26, in the embodiment of
In the embodiment illustrated in
Thus, in
The embodiment of
The embodiment of
As used herein, a “structurally reinforcing member” is that structure which results, between the sides of adjacent ones of the foam blocks, when reaction curable resin is infused into, or otherwise caused to flow through, a panel precursor. Thus, a structurally reinforcing member incorporates the fiber, e.g. fiberglass, of the wrapping layers 34 (
As illustrative of the unitary nature of the entire structure which makes up the fiber-reinforced polymeric structure of panel 10, the boundary lines between the wrapping layers and the inner and outer layers have been omitted in
In the alternative, layer 60 can be omitted and wrapping layers 34 can optionally extend about the entire outer perimeters of the foam blocks with the fire-rated boards trapped between the wrapping layers and the foam blocks.
So far, construction panels 10 have been discussed in terms of their use in “fixed-location” buildings. Such panels can also be used in mobile structures, e.g. transport vehicles such as trains, busses, and other mass transit vehicles; as well as truck boxes, shipping containers, mobile storage units, and the like.
Construction panels 10 of the invention can be made by a variety of known processes. A vacuum infusion molding process is illustrated following.
In a typical vacuum infusion process, dry fiberglass, containing no resin is loaded into a mold, the mold is closed and sealed; air is evacuated from the closed and sealed mold, and resin is infused into the mold as the air is being evacuated from the mold. In general, a vacuum infusion mold includes a lower e.g. female mold element and an upper e.g. male or gender-neutral mold element. Depending on the product being made either or both of the upper and lower mold elements can have either or both male and female features, as well as gender-neutral features.
At the beginning of the process, the interior surfaces of the upper and lower mold elements, including any recesses, are optionally coated with conventional mold release material. Such release materials are known in the art, and are selected according to the materials in the surfaces of the mold, as well as the specific resin being used to fabricate the construction board. In the alternative, a mold release agent can be incorporated into the resin. Next, the respective dry elements of the panel members are loaded into the mold, starting with elements which fit into any female cavities in the mold. Thus, in a mold for making a panel as in
Next, a layer of fiberglass fabric, representative of layer 60, is placed over the full length and width of the lower mold element, from the right side to the left side, top to bottom of what will be the construction panel. The layer of fabric is laid over the entirety of the length and width of the lower mold element, including over the top surfaces of stud cores 36.
Next, foam blocks 32, pre-wrapped with layers 34 of fiberglass on three surfaces of the foam blocks, with fire-rated boards 26 stapled to the foam blocks through overlying edges of the wrapping layers 34 (
Fiberglass fabric, representative of outer layer 12, is then laid over the foam blocks, covering the lengths and widths of all the foam blocks.
The upper and lower mold elements are brought together, with a seal therebetween, so as to form a closed and sealed mold, with the respective dry elements of the construction panel in the mold cavity.
The mold cavity is then evacuated at a first end/side of the mold, drawing a vacuum which removes substantially all of the air out of the mold cavity. As the air is withdrawn from the mold cavity, resin is introduced into the cavity at one or more resin feed ports located at e.g. an opposing second end of the mold. The resin flows to all areas of the mold where air has been removed, thus filling the voids left by the evacuating air and forming the continuous resin matrix about and through all of layers 12, 18, 34, 60, and 62 of fiberglass which encompass foam blocks 32 and stud cores 36.
Thus, resin flows into intimate bonding contact with the surfaces of the foam blocks 32 which are not overlaid by fire-rated boards 26. Resin also flows into intimate bonding contact with the surfaces of stud cores 36. As a result, the resin in the mold flows to all areas which have been evacuated by the removed air, thus creating a continuous matrix of resin throughout the structure in all of the fiberglass layers which are in the mold.
Resin flow channels, not illustrated in the drawings, can be used as desired in the respective foam boards 32 and stud cores 36 to facilitate the flow of resin to all parts of the mold, thus to fully infuse all areas of the fiber-based layers with resin.
Once the mold has been closed and evacuated, and the necessary quantity of resin has been infused into the mold, the mold is maintained in its closed and sealed condition until the resin in the mold has cured. In the process of curing the resin, the mold may be heated, or not, depending on the thermal requirements associated with the curing of the specific resin being used. Where heat is required, heat is applied. Where heat is not required, the resin is typically cured at ambient temperature of e.g. 60-80 degrees F. (16-27 degrees C.).
The thus-produced fiber-reinforced polymeric construction panel product is removed from the mold upon sufficient progress of the curing of the polymer.
The polymer which is used in the fiber-reinforced polymeric layers can be selected from a wide variety of conventionally available multiple-part reaction-curing resin compositions. Typical reaction curing resin is a 2-part liquid where two liquid parts are mixed together before the resin is applied to the fiber substrate. Third and additional components can be used in the reaction mixture as desired in order to achieve the desired level of reaction curing of the resin, as well as to achieve desired properties in the cured resin. The uncured resin mixture should be sufficiently liquidous to be readily incorporated into a fiber base sheet/substrate thereby to fill in all of the voids in the substrate and/or to so flow over, under, around, and through the fiber composite in a forming and/or molding process. Examples of useful 2-part reaction curing resins include, without limitation, acrylic resins, epoxy resins, vinyl ester resins, polyester resins, polyurethane resins, and phenolic resins.
Those skilled in the art know that each of the above noted reaction curable resins represents a large family of chemically reactable materials from which a user can select to make the resultant reaction-cured construction panel, and those skilled in the art are capable of selecting reaction resin combinations for the uses contemplated in the invention. A suitable reaction curable experimental resin is an acrylic resin available as MODAR® from Ashland Chemical Company, Covington, Ky. Another suitable resin family is the phenolic resins, available from a variety of suppliers. An exemplary such phenolic resin is CELLOBOND® J2042L available from Momentive Specialty Chemicals Inc., Louisville, Ky.
Where desired for resin compounding purposes, more than two such resins can be mixed to obtain a desired set of properties in the reacted product or the reaction process.
The resin can be modified by addition of filler to the polymeric composition, in the amount of up to about 200 parts filler by weight to each 100 parts polymer, optionally 30 parts filler to about 100 parts filler per 100 parts polymer, optionally about 40 parts filler to about 60 parts filler per 100 parts polymer. About 50 parts filler to 100 parts polymer has been found to be highly satisfactory.
For any set of reaction materials which are used in the invention, any conventional additive package can be included such as, for example and without limitation, catalysts, anti-oxidants, UV inhibitors, fire retardants such as ATH, fillers, intumescent material, fluidity-control agents, whether organic, inorganic, or polymeric, to enhance the process of applying the resin and/or curing the resin, and/or to enhance the properties of the finished product such as weather resistance, fire resistance, hardness, shrink control, mold lubrication, colorants, fillers, and other desired features.
However where, as in the invention, a fire-rated layer is incorporated into the construction panel, the efficacy of a fire retardant or an intumescent material in the polymer is of less importance.
Each set of two or more materials, along with suitable additives, can be mixed and reacted. to make the resultant resin product. Further, each set of such two or more reaction materials develops its own set of resultant physical and chemical properties in light of the curing or plasticizing, and molding processes. Especially the physical properties of resultant fiber-reinforced structural material are influenced by the affect of the included fibers and fillers, such that more than two such reactants may be useful in achieving, in the finished polymer, a desired set of physical properties.
In general, dry fiber is used as the fiber base for the polymer/fiber composite. E.g. dry fiber substrate, woven cloth, fiber matt and/or rovings are used for structural elements of the construction panels, along with foam blocks 32, and any core material which may be used to establish the shapes of the studs. Enough resin is added to the fiber substrate to fill all voids, whereby there should be no air inclusions, or so few air inclusions as to have no material effect on the physical or chemical stability, or the physical properties, of the construction panel. Overall, the glass/resin ratio is as high as can be achieved while not leaving any significant, deleterious voids in the resultant structural element once the resin is cured.
Given the requirement to minimize voids, and using conventional layer-development techniques, the resultant structural layer product, e.g. layer 12 or 18, or the structurally reinforcing members, is about 30 percent by weight to about 65 percent by weight fiber, and correspondingly about 70 percent by weight to about 35 percent by weight resin. Optionally, the resultant layer is about 40 percent by weight to about 60 percent by weight fiber and about 60 percent by weight to about 40 percent by weight resin. A typical resultant cross-section is about 45 percent by weight to about 55 percent by weight fiber and about 55 percent by weight to about 45 percent by weight resin, optionally about 50 percent by weight fiber and about 50 percent by weight resin. Where filler is used, the weight of the filler, as well as all other resin additives, is taken to be part of the above-recited resin fraction.
According to well-known technology, where fiberglass is used as the fiber, the number of layers of fiberglass, in combination with the weight of the fiberglass per layer, in general determines the thickness of the resultant layer after the resin-impregnated layer is cured. For example, multiple layers of a 12-30 ounce per square yard (407-1016 g/m2) layer of woven fiberglass cloth can be impregnated to fill all voids, and to thereby achieve a resultant cured structure which is typically between about 1 millimeter and about 12.7 millimeters (about 0.04 inch and about 0.50 inch) thick. The greater the number of layers of fiberglass, of a given thickness, which are impregnated, typically the greater the thickness of the resulting impregnated and cured composite reinforced layer.
The purpose of foam 24, such as foam blocks 32, can be two-fold. First, the foam can optionally provide some contribution to the structural integrity and strength of the construction panel structure by being sufficiently rigid, namely a rigid foam, and sufficiently affixed to the adjacent panel elements, that the foam acts as part of the unitary panel structure, namely contributes significantly to fixing the outer 12 and inner 18 layers, and any structural reinforcing members, in their designed configurations under normal loading of the panel, whether vertical gravitational loading, or lateral loading such as lateral ground loads in below-grade applications, and lateral wind and/or water loads in above-grade applications. Thus, the foam can make a substantial contribution to the dimensional stability of construction panel 10. However, in other embodiments, the foam can be substantially resiliently deformable such that the rigidity contribution of the foam 24 or foam blocks 32 may be as little as substantially nil.
Second, the foam contributes a substantial thermal insulation property to the resulting construction panel construct. In achieving a desired level of thermal insulation while e.g. retaining the foam as a dosed-cell material, the foam has a density of about 1 pound per cubic foot (pcf) (16 kg/m3) to about 12 pcf (192 kg/m3), optionally about 2 pcf (32 kg/m3) to about 8 pcf (128 kg/m3), optionally about 2 pcf (32 kg/m3) to about 5 pcf (80 kg/m3). Lighter weight foams can be used so long as the desired level of thermal insulation is achieved and the desired level, if any, of structural contribution to the strength of the panel is achieved. While heavier weight foams can be used, and typically provide greater increments of structural strength, relatively heavier weight foams may provide less than the desired level of thermal insulation properties, and require use of additional mass of the foamed material which adds to the cost. In general, the foams used in the invention are relatively lighter weight closed-cell foams of about 2 pcf (32 kg/m3) to about 5 pcf (80 kg/m3). Regarding foam layer 24, corresponding foam blocks 32 can be made from a wide variety of compositions including, without limitation, extruded polystyrene foam, expanded bead polystyrene foam, rigid urethane foam, phenolic foam, or polyisocyanurate foam. The foam is moisture resistant, preferably moisture proof, and is chemically and physically compatible with, and thus does not chemically react with, the compositions and structures of outer layer 12 and inner layer 18, as well as any structurally reinforcing webs. A suitable foam board is 2 pounds per cubic foot (32 kg/m3) polyisocyanurate foam, available from Elliot Company, Indianapolis, Ind.
Foam, e.g. boards 24 or blocks 32, optionally fills all, or substantially all, of the spaces between the respective surfaces of outer and inner layers 12 and 18, and between the structurally-reinforcing webs, and in some embodiments the foam board is in surface-to-surface contact with the respective layers and structurally reinforcing members as such layers define the cavities in which the foam is received. In addition, the foam is adhered to the respective structural layers and structurally reinforcing members with which it is in contact so as to absorb sheer forces between the foam and the respective structural layers and reinforcing members.
Blocks of the foam can be brought into surface-to-surface relationship with the fiberglass and resin as part of the process of fabricating the construction panel, whereby the foam is in surface-to-surface contact with the respective layer precursors and becomes wetted by the uncured resin. With the foam in contact with the in-process fiber-reinforced layer precursor, and wetted by the fiber-reinforced layer precursor, the setting of the resin as the reaction curing resin polymerizes, bonds the foam to the respective outer and inner layers, and/or wrapping layers, and any reinforcing members as applies, whereby no separate adhesive is typically required to bond the foam to the respective structural elements.
Given a typical thickness of the main run core section of a construction panel, namely between the first and second outermost surfaces 16, 22, of about 3 inches (7.6 cm), given that the spaces between the inner and outer layers are filled with light weight insulating foam, construction panels of the invention typically provide thermal insulation factors between layers 12, 18 of about R15. An additional e.g. R13 can be achieved by installing fiberglass insulation batts in channels 52 between any studs, thus to achieve an overall insulation factor capability of about R28 in typical walls made with panels of the invention, and thus achieving thermal insulation properties far superior to most concrete wall products, even insulated concrete wall products, currently available to the consuming public. Such superior insulation value can thus decrease heat loss to a substantially greater extent than most foundation wall products currently available to the consuming public.
Non-foam-based fire-rated boards 26, 30, 42, 46, 54, and 56 can all be sourced using a common material or common board product. Any board, typically a non-foam-based board, capable of meeting the fire testing requirements can be used. Typically, such boards are based on either gypsum or concrete compositions, and are reinforced with some fiber content.
Examples of conventionally-available materials which can be cut to size to serve as the fire-rated layers or fire-rated boards, are the following products which are believed to have the recited general compositions:
DUROCK®—cement+aggregate+fiberglass
FIBEROCK®—Gypsum+fiberglass
DENSGUARD®—Gypsum 30 fiberglass+an acrylic coating (nonflammable)
HARDIBACKER®—Board−Cement+sand+cellulose fiber
WONDERBOARD®—cement+nylon mesh
The above-noted non-foam-based boards are all believed to be commercially available. None of such boards are believed to contain foam which contributes either to thermal efficiency of construction panel 10, or to dimensional variability of the respective board. However, any presence of foamed materials is insignificant in the invention so long as the foam does not detract from the fire-rating features of the board.
Suitable non-foam-based fire-rated boards have thicknesses of about 0.25 inch to 0.5 inch. The specific thickness will depend on the specific test used in determining fire-rating suitability. In many instances, thickness of 0.25 inch (6.3 mm) or 0.38 inch (9.6 mm) is entirely satisfactory.
Given the small thicknesses of the non-foam-based boards, the relative fraction of the thickness of the construction panel occupied by e.g. boards 26 or 54 is nominal compared to thickness of the panel, and/or depth of the channel in the case of the board serving as the outside surface of the panel. For example, in a panel which is nominally 3 inches thick, a board 0.25 inch thick occupies only 8% of the thickness of the panel. If the board is 0.5 inch thick, or where two boards, each 0.25 inch thick, are used on both the inner and outer sides of the panel, the board occupies only about 17% of the thickness of the panel.
The embodiments illustrated herein show the fire-rated non-foam-based boards as either entirely enclosed within the panel, such as boards 26 and 46, or on the surface of the panel, such as boards 54 and 56. Boards 42 are shown either enclosed in the studs in the enclosed embodiments or on the surfaces of the studs in the surface embodiments. While not illustrated, the invention fully comprehends embodiments where fire-rated non-foam-based board is enclosed inside the panel on one side of the panel, such as the inner side of the panel, and is on the exterior surface of the panel on the other side. Or the e.g. boards 26 can be enclosed inside the panel on the inner side and boards 42 can be on the outer surfaces of studs 28.
Exemplary of fire-rated foam-based boards which can be used for layer 24 or foam blocks 32 and/or stud core 36, non-limiting of foam materials which satisfy respective ones of the fire-rating requirements, and which negate the need to use the above-recited non-foam-based fire-rated barrier boards, there can be mentioned THERMAX™ sheathing, available from Dow Chemical Company, Midland, Mich. THERMAX is a foam-based board which has a polyisocyanurate foam core at about 2 pounds per cubic foot (32 kg/m3) density laminated on opposing surfaces with 1 mil (0.25 mm) thick aluminum foil facing sheets. The THERMAX board is reinforced with fiberglass reinforcement.
Another exemplary fire-rated foam board product, tested successfully per UL 1715, which board can be used for. layer 24 or foam blocks 32 is the TSX-8500™ series of foam boards available from RMax, Dallas, Tex. The TSX-8500™ series of foam boards have polyisocyanurate foam cores at about 2 pounds per cubic foot (32 kg/m3), laminated on opposing surfaces with fiberglass-reinforced aluminum foil facing sheets. The aluminum foil on the side of the board which is more likely to be exposed to fire conditions is 1.5 mil (0.4 mm) thick.
In still another embodiment, not illustrated in the drawings, a fire-rated foam-based board can be used as layer 26, 26A, etc in the main body of the panel, e.g. adjacent a wrapping layer 34, adjacent an inner layer 18, or adjacent an interior fiberglass layer 60; and a non-fire-rated board 32, 32A can be used between the fire-rated board and the outer layer of the construction panel. For example, a THERMAX board 0.5 inch (12.5 mm) thick can be used as a layer 26A and a non-fire-rated board can be used as foam block 32A.
Similarly, a fire-rated foam-based board can be used as a board layer 42 in the studs, between the core 36, which is in such cases typically a non-fire-rated foam, and the surface of the stud which is exposed to the ambient environment.
In light of the above, the invention provides the necessary fire rating for construction panels without substantially intruding on the thicknesses of the remaining materials which provide other desired features/properties to the panel.
The invention generally comprises construction panels, and methods of fabricating construction panels in controlled-environment manufacturing facilities. Thus, walls and wall panels can be delivered from the manufacturing facility in a variety of lengths and/or heights. In addition, the panels can be cut as needed at the construction site such as to accommodate specific length requirements as well as to create rough openings for windows and/or doors.
Although the invention has been described with respect to various embodiments, it should. be realized this invention is also capable of a wide variety of further and other embodiments within the spirit and scope of the appended claims.
Those skilled in the art will now see that certain modifications can be made to the apparatus and methods herein disclosed with respect to the illustrated embodiments, without departing from the spirit of the instant invention. And while the invention has been described above with respect to the preferred embodiments, it will be understood that the invention is adapted to numerous rearrangements, modifications, and alterations, and all such arrangements, modifications, and alterations are intended to be within the scope of the appended claims.
To the extent the following claims use means plus function language, it is not meant to include there, or in the instant specification, anything not structurally equivalent to what is shown in the embodiments disclosed in the specification.
Number | Date | Country | |
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61571290 | Jun 2011 | US | |
61573799 | Sep 2011 | US |