Patent Grant
9500023
Field of the Invention
The present invention relates generally to structural elements for a building, and more particularly to a device, method, and system for framing openings in building walls.
Description of the Related Art
Buildings, such as houses and other structures, are commonly constructed of frame-constructed walls that separate the inside of the building from the outside, and that separate rooms from one another, as well as that support a roof and possibly upper floors of the building. The frame-constructed walls are formed by so-called stick members, which include vertical studs, horizontal wall plates, and horizontal load-bearing headers or lintels over portals, doors, windows and fireplaces. The stick members for a stick-built wall may be of wood, steel, or other materials. The frame-constructed walls serve as a base for wall coverings, such as wallboard, siding, wall sheathing, etc.
The walls typically have openings for doors and windows, for example, that are formed in the wall and provided with framing that forms a rough opening for the window or door and that supports the window or door in the wall. In one example, a framed rough window opening has a vertical king stud on each side of the opening extending from the bottom or sole plate of the wall to the top plate of the wall structure. Vertical jack studs are provided below the window opening and vertical cripple studs are provided in the wall above the window opening. Horizontal members of the rough window opening include a sill at the bottom of the window opening and a header or lintel extending horizontally across the top of the opening. Vertical trimmer studs are provided on the sides of the opening extending from the sill to the header or from the sole plate to the header. Doors may be framed in the same way but without the use of a sill and jack studs that form the wall below a window.
Every structural opening of a standard stick-built structure requires at least two king studs, two jack studs, and one header. Typically, these three elements are constructed using solid virgin lumber, the construction of which requires multiple calculations and cuts by the contractor, resulting in pieces of scrap wood and using valuable time. These calculations are based off of the expert knowledge that the professional construction worker has gained. Following this process, the three elements are commonly nailed together to form the opening. In the majority of new construction, walls are framed flat on the floor and then stood up and set in place. With this form of framing, doors and windows are laid out first.
The process of remodeling, although different, also places a major focus on the importance of structural openings. With the top plates and sole plates already installed, studs are cut and installed vertically, to create new openings.
In both cases, the king studs are installed first. The king stud is the piece of lumber that runs from the bottom plate or sole plate of the wall (a horizontal piece of wood usually 1.5 inches thick that acts as the base of the wall to which vertical pieces may be attached) to the top plate of the wall (a horizontal piece that runs parallel to the sole plate that forms the top of the wall). In most states, building codes require that the top plate is to be doubled, making it a total of 3 inches thick. The purpose of the king studs is to uphold the structural integrity of the stud wall and to hold the header in place laterally. King studs can be purchased in pre-cut lengths for standard ceiling heights. For example, for a ceiling height of 8 feet (96 inches), a pre-cut king stud is 92⅝ inches in length. This accounts for a 1.5 inch thick sole plate and a 3 inch top plate. This same calculation is applied to ceilings that are 9 feet and 10 feet high.
Second components of a structural opening are the jack studs (also called trimmers). Jack studs are cut and nailed at the inside surfaces of the king studs relative to the wall opening. The jack studs also rest on the sole plate of the wall. The jack studs are responsible for carrying the header and for distributing the bearing weight that the header carries, down to the base plate, ensuring structural stability. The jack studs are typically cut on the job site, and are measured depending on the door, window, or opening height. For example, for a 6 feet, 8 inch (80 inch) tall door, the jack studs are cut to 80.5 inches and installed on the sole plate. It is common knowledge to construction professionals that in order to fit a 6 feet 8 inch door, the opening in the wall must have a height of roughly 82 inches. The same calculation applies to doors that are 7 feet tall and 8 feet tall. Both jack studs and king studs of a typical building structure are formed of flat pieces of conventional lumber.
The final component of the three components of a structural opening, according to certain embodiments, is the header. The header can be described simply as the structural piece that spans the opening formed by the jack and king studs. The header is placed on top of the jack studs. Whatever weight the header bears is therefore transferred to the jack studs and down to the sole plates. The header is typically placed directly under the top plate, between the two king studs, and bearing on the two jack studs. The amount of weight that the header bears can vary as it is responsible for supporting the weight of the ceiling, as well as any floors above. The load can often determine the height, width, and composition of the header. Headers are normally built using solid conventional lumber. However, headers can also be of engineered materials, sometimes including sandwich structures of steel or plywood depending on the structural strength required. If the only bearing responsibility for the header is to support sheet rock or other wall portion above the header, a hollow header may be used to reduce cost and save material. Headers are easily manipulated and can also be insulated in order to increase the R-value (insulating value) of that area of the building structure. The R-value is the ability of a given space to resist heat flow. A high R-value means less escaping heat or influx of heat when an air conditioner is in use, which can lead to increased savings on energy bills.
The typical necessary dimensions (especially width) of the header are also common knowledge to house construction professionals, for example. The two 1.5 inch jack studs must be accounted for. For a 24 inch wide door, which requires a rough 26 inch wide opening, the header must be cut to 29 inches. When the opening is much larger, it is common for two jack studs to be used on either side of the opening. As a result, the length of the header must account for an added 3 inches on each side, for a total of 6 inches of additional length.
Certain embodiments of the present invention provide a pre-fabricated framing kit and/or framing elements for structural openings in walls, such as for doors, windows, and the like. In certain embodiments, the window framing components are formed to fit together in interlocking fashion. The framing kit and/or framing elements of certain embodiments includes modified king studs having a C-shaped cross section, modified jack studs that fit together with and extending partially into the C-shaped king studs, and a header that interlocks into the king studs.
Certain embodiments use one or more brackets to secure the framing elements to one another and to other elements of the wall. Certain embodiments include a window sill plate and jack studs below the window sill plate well as jack studs between the window sill plate and the header as a trimmer stud. Certain embodiments include jack studs above the header as cripple studs.
Certain embodiments provide a kit for framing a wall opening, such as a window or door, the kit including brackets to connect the kit components to one another and to wall elements. The brackets may be provided as flat elements that are bent into shape during building of the wall opening. The brackets may instead be provided as formed elements that are pre-bent to shape.
Certain embodiments provide components for locating a wall opening, such as a window or door, adjacent a wall junction.
Referring to the figures, in
The king stud 10 may have a generally uniform width and thickness along its length. Embodiments of the king stud are possible that have variations in width and thickness, variations in shape or cross section, or variations in other characteristics. The king stud 10 may be of any length and may have any width and thickness dimension. The king stud 10 is dimensioned to fit in and form a part of a wall of a building, for example. In certain embodiments, the king stud 10 has the dimensions of a standard 2×4 (two by four) building member. Current standard dimensions of a 2×4 building member are nominally 1.74 inches by 3.5 inches. The king stud 10 may be provided in other building member dimensions, including standard 2×3 (two by three) and 2×6 (two by six) building member dimensions, or in any other dimension known in the building trade.
The channel 12 may be of any width and depth. In a certain embodiments, the channel is 1.5 inches deep and has a width of 3.5 inches to 5.5 inches. Other dimensions are of course possible.
A jack stud 20 is provided as a second element of the kit or system. The jack stud 20 is a structural member that has a predetermined length and a generally rectangular shape. The jack stud 20 includes two edge channels 22 formed along opposite edges on one side of the jack stud 20 that extend the length of the jack stud 20. The edge channels 22 form a raised strip 24 that extends the length of the jack stud 20. Embodiments are possible in which the edge channels 22 and/or the raised strip 24 extend along only a portion of the jack stud's length. In certain embodiments, the raised strip 24 is of a width to fit into the channel 12 of the king stud 10. The raised strip 24 may be of a thickness corresponding to the depth of the channel 12, or may be of a thickness less than the depth of the channel 12, or may even be of a thickness greater than the depth of the channel 12.
The jack stud 20 has a back panel 26 on the side opposite the edge channels 22. The back panel 26 of certain embodiments has a width that is approximately the same as the width of the king stud 10. The jack stud 20 may be of a width greater than the king stud 10 or less than the king stud 10 in other embodiments. The back panel 26 forms ears 28 that extend beyond the raised strip 24 along the opposite edges of the jack stud 20.
A header 30 is provided as another element of the kit or system. The header 30 is a structural member that has a predetermined length and is generally rectangular in shape. The header 30 includes an elongated body 32 and an end projection 34. A similar end projection extends from the opposite end of the header 30. The end projection 34 is of a size and shape to fit into the channel 12 of the king stud 10. The end projection 34 may extend from the elongated body 32 by a distance approximately equal to the depth of the channel 12, or may have a length that is greater than or less than the channel depth. The end projection 34 is formed by an end block 36 that is mounted between two header planks 38. The header planks 38 form the elongated body 32. The header planks 38 are spaced from one another by the thickness of the end block 36. A space 40 between the header planks 38 may be either left empty or filled. For example, the space 40 may be filled by a plank, by insulation, or by other structural elements or material.
The king stud 10, jack stud 20, and header 30 may be formed of wood lumber, composite material, manufactured wood, metal such as steel or aluminum, or other building materials. Each may be of the same material or the elements of the kit or system may be of two or more different materials.
The king stud 10, jack stud 20, and header 30 fit together as interlocking parts. The king stud 10, jack stud 20, and header 30 may be fastened to one another by nails, screws, glue and/or other fasteners. The fasteners may be provided where the elements interlock.
Turning to
The door frame 42 is provided as part of a wall structure 48 of a building, such as a wall between rooms of the building. The wall structure 48 may instead be an outside wall of the building. At the base of the wall is a bottom plate 44 on which the lower ends of the king stud 10 and jack stud 20 are mounted. The bottom plate 44, also referred to as a sole plate, rests on the floor, indicated generally at 46, of the building. A portion of the bottom plate 44 is cut out at the doorway being framed by the door frame 42. In some walls, the bottom plate 44 extends across the bottom of the door opening.
Wall studs 50 extend from the bottom plate 44 to a top plate 52. The top plate 52 extends along the top of the entire wall, although the top plate is shown cut away for the sake of clarity. The king stud 10 extends from the bottom plate 44 to the top plate 52. Additional wall studs 50 and potentially other framing elements are provided to form the wall frame for the whole wall of the building. The top plate 52 is formed by a double structural member, in the illustrated embodiment. Other constructions for the top plate are of course possible, including single beams or constructed beams. The top plate 52 extends above the door frame 42 and the king studs 10 extend into contact with the underside of the top plate 52, although this is not shown in
A structural panel 56 is provided on the bottom plate 54 that includes two support strips 58. The structural panel 56 and support strips 58 are the subject of U.S. Pat. No. 8,429,863, which is incorporated herein by reference. The structural panel 56 and support strips 58 are provided at a wall junction of two walls. Although cut off in the drawing to provide a clearer view of the door frame, the structural panel 56 and support strips extend from the base plate to the top plate in certain embodiments. The user may wish to build a door frame, window frame, or doorway adjacent the wall junction. In certain embodiments, the structural panel 56 and support strips 58 take the place of the king stud for the side of the doorway or window closest to the adjoining wall. The support strips 58 are spaced apart by a distance to accommodate the raised strip of the jack stud and the header end or sill plate end. The jack stud is positioned into the gap between the support strips 58 and is fastened in place. The header and/or sill plate are attached to form the doorway or window opening. The side of the opening opposite the support strips 58 and structural panel 56 is formed with the king stud and jack stud as shown herein. The structural panel 56 and support strips may be attached to the base plate 54 by a bracket, as shown in the above-referenced patent.
The illustrated wall structure is but one example of a wall structure in which the door frame 42 may be provided. Other wall structures are also possible and within the scope of this invention. The wall may be completed by providing electrical wiring, plumbing, heating, and other utilities, adding insulation, and finishing the wall with drywall board, plaster, paneling, or other wall materials. Outside walls may include a vapor seal layer, and may be finished using siding, brick, shingles, or other external wall treatment or material.
The depth of the channel 12 is greater than the height of the raised strip 24 in the illustrated embodiment. The dimensions result in an interior space 60 within a beam 62 formed by the joined king stud 10 and jack stud 20. The beam 62 may be formed to have a greater or lesser interior space. For example, the raised strip 24 of the jack stud 20 may completely fill the channel 12 so that no interior space is provided within the beam 62. Or only a small interior space 60 may be provided, or a large interior space may be provided.
The king stud 10 and jack stud 20 may be fastened together, such as by nails, screws, glue, rivets, or other fasteners or fastening means. Any fastener to affix the king stud 10 and jack stud 20 to one another may be used.
Referring to
The dimensions of the illustrated embodiment result in, a king stud 10 and jack stud 20 and header 30 that are all of the same thickness within the wall and have even outside surfaces. It becomes easier to form the wall of wall board, paneling, or other materials without irregularities in the wall surface or the requirement to shim wall panels or add large quantities of drywall compound to achieve a smooth and even wall.
The king stud 10 and header 30 are fastened to one another by nails, screws, glue, rivets, or other fasteners or fastening means. Any fastener to affix the king stud 10 and the header 30 to one another may be used.
Turning now to
The bracket 64 is fastened to the king stud 10 and the bottom plate 44 by nails 76 in the illustrated embodiment. The bracket 64 includes circular nail openings 78 in the side portions 74 for receiving nails 76 inserted at generally right angles to the bracket 64. The bracket 64 includes angled nail receiving openings 80 for receiving nails 76 at an angle to the bracket 64. The angled nail receiving openings 80 are partial cup-shaped projections extending from the surface of the bracket 64 to receive a nail 76 at, for example, an approximately 45 degree angle to the surface of the bracket 64. The projections form guideways for the nails or other fasteners.
The jack stud 20b of
In
The header 30b of
With reference to
In
Between the sill plate 100 and the header 104 are provided second jack studs 108. The second jack studs 108 include raised strips that extend into channels on the king studs 96 and 98, like other jack studs shown herein. The second jack studs 108 face toward one another at the window opening 102. Said another way, the second jack studs 108 face the window opening 102. The second jack studs 108 may be referred to as trimmer studs.
Above the header 104 may be provided third jack studs 110 that extend from the header 104 to the top plate 94. The third jack studs 110 may be referred to as cripple studs. The third jack studs 110 may have raised strips that extend into channels on the king studs 96 and 98. Similar jack studs as cripple studs may be provided on embodiments forming a door opening or doorway.
The window sill plate 100 and the header 104 shown in
Turning to
The bracket 166 is shown on what may be referred to as the front of the frame. A bracket 180 may also be provided on the back of the frame. The bracket 180 on the back of the frame may be of the same shape or of a similar shape as the bracket 166. It is possible that the front side bracket 166 and back side bracket 180 have different shapes. In one example, the second flange 172 of the front side bracket 166 extends less than half way across the jack stud 162. The back side bracket 180 has a similar flange 182 that extends on the jack stud 162. The flanges 172 and 182 are of lengths so as not to contact or interfere with one another. All flanges on the brackets may be formed to extend less than have the distance of the member on which they are bent to avoid interference with flanges on the opposing side.
The bracket 166 has the third flange 174 on the header 164 extending greater than half way across the surface of the header 164. To avoid interference or overlap with flanges on the bracket 180 on the back side of the frame, the third flange 174 is offset away from the king stud 160 to leave a gap between the flange 174 and the jack stud 162. The back side bracket 180 has a flange 178 that is offset toward the king stud 160 to fit into the gap left by the front side flange 166. The offset positions of the two flanges 174 and 178 avoid interference between the flanges, permitting both the front side bracket and the back side bracket to be attached at the junction of the parts.
Multiple brackets may be provided in certain embodiments. The brackets may have shortened flanges, for example like flanges 172 and 182, or offset flanges, for example like flanges 174 and 178, or the brackets may have both types as in the illustrated example. The brackets may be of a mirror image shapes for connection opposite sides of the king stud/jack stud/header joint. Other bracket shapes are possible and within the scope of the invention.
A top plate bracket 184 is provided between the top plate 186 and the king stud 160. The top plate bracket 184 may be configured like the bracket for connecting the king stud to the bottom plate. Other shapes and configurations of brackets are also possible.
In certain embodiments, the brackets are provided to the user as generally flat sheet material that has been cut to shape and provided with nail holes and nailways. The user may bend the flanges of the flat brackets into shape while assembling the frame elements. The flat brackets facilitate packing and shipping, and may be bent to accommodate variations in the dimensions of the joint to which the bracket is attached. The brackets may be scored, cut, formed or otherwise provided with features that facilitate bending along the desired bend locations. It is also possible that the brackets are provided in a preformed, pre-bent condition so they are ready to mount to the joint. The same is true for all brackets used in constructing the frame.
The frame kit for a door or doorway includes a single header, two king studs and two jack studs, and possibly brackets, fasteners, instructions, and/or other materials. The frame kit as shown in
Other wall openings may be provided using the present elements and/or kit as well, including wall openings, skylights, passageways, hallway entrances, or other structural features.
There is shown and described herein a device, system, and method for framing doors, windows, and passageways in a building or other structure. The device may be provided as a product that includes a pre-fabricated rough framing kit for a door, for a window, or for a passageway. The framing kit product provides improved components used in forming a structural opening in a wall. In a particular embodiment, the framing kit includes improved components for the three primary components used in constructing a structural opening, namely an improved king stud, an improved jack stud and an improved header. The framing kit simplifies the construction of a structural opening, particularly for a do-it-yourself builder or for those less experienced at building. Trial and error cutting of materials is avoided, which can result in lower costs. The assembled components provide better structural integrity, material conservation, efficiency, and energy conservation when constructing a building opening.
Like conventional framing, the present product, device, system and method relies on three main components. The components are modified as compared to conventional components. By providing modified or engineered components, including modifications to the configuration and/or materials used, the structural integrity of the building components may be controlled. According to the present device and method, pre-cut pieces are provided for the components, which allow for quick and easy assembly of the components in a wall of a building or other structure. The pre-cut components in the kit provide elements and structures that are familiar to a professional home builder, carpenter, or other construction worker and provide simplicity for a novice seeking to assemble building elements. Embodiments of the present device and method are provided to accommodate all (or most) standard door widths and heights. An important feature is that embodiments of the product can be utilized in new construction, and can also be used in remodeling as well.
In certain embodiments, the product includes a kit that contains pre-fabricated headers, king studs and jack studs, which are pre-cut and measured to fit designated openings, such as doors, windows, or passageways. The king stud of a preferred embodiment of the kit is configured in the shape of the letter C, although other shapes are possible. The C-shape of the king stud has an inside surface contains two approximately 90 degree corners, although the invention is not limited to that shape. The C-shape provides an increase in the surface area of the king stud. A jack stud is provided to take advantage of the increased surface area of the king stud when placed into contact with the king stud. In particular, the jack stud and header is received in the king stud in an interlocking fashion. The king stud of certain embodiments are pre-cut to fit standard ceiling heights and account for standard wall thicknesses (for example, walls formed using 2×3, 2×4, or 2×6 construction elements) or any other potential wall thickness. The king stud may be provided in different thicknesses or may be larger or smaller in other dimensions based upon the structural requirements that are to be met.
Another aspect of certain embodiments is to include in the kit metal brackets that are to be used to attach the king stud to both the top plate and sole plate. Fasteners or brackets could be added to other parts of the system as well. The brackets are not required in every embodiment but may increase the stability of the structure when used.
The jack stud according to preferred embodiments is configured with a shaped portion that fits into the king stud. The jack stud preferably interlocks with the king stud while also supporting the header that is disposed above the jack stud, and bearing down onto the sole plate that is below the jack stud. Like the king stud, the jack stud of certain embodiments is pre-cut to accommodate standard door heights and widths. Examples of jack studs are provided for door heights of 6 feet, 8 inches; 7 feet; and/or 8 feet. Like the king stud, the jack stud may be of engineered configuration and materials. The jack stud can be provided with either smaller or larger dimensions based on load requirements of the wall opening. The jack stud of certain embodiments may be provided separately or may be provided as part of the kit, or the jack stud and king stud can be joined to one another (pre-assembled) before the product is provided to the customer/builder, further simplifying the assembly process for the builder. In an alternate embodiment, the jack stud and king stud may be provided as a formed single piece element.
The header of certain embodiments is configured as a pre-cut component that is sized to fit the span of standard wall openings. The header of preferred embodiments is pre-cut not only to fit the span and height of the opening, but also to fit into the king stud in an interlocking fashion. The header may be provided as a pre-assembled unit with the king studs and jack studs, or as separate pieces. The header and the jack stud both interlock with the king stud. The shape, dimensions, and materials used in the header may be selected and engineered based upon load requirements, R-value needs, etc. The present header according to certain embodiments is of a size, material and configuration that are selected based on the kit in which it is to be included. For example, heavy load bearing components are provided together in a kit for heavy load installations, whereas a lighter load kit will be provided with components for bearing lighter loads. The header provided in the kit may be selected from insulated headers, solid headers, reinforced headers, and the like. Each component of the rough wall opening is pre-fabricated, especially the header, so that it is assured that measurements will be accurate and that each element of the design will be an optimal fit in relation to each other.
According to the present device and method, the header still bears on the two jack studs, however the greater contact surface area between the jack stud and the king stud changes the way that the weight of the header is transferred between the jack stud and the king stud. Multiple points of contact between the king stud and the jack stud ensure a snug and more stable fit as well as sharing of the load by the header.
In a usual construction, the component pieces of a rough frame of a wall opening are nailed together, which can be used here. The configuration of the components permits the use of glue, nails, screws, and/or brackets if desired. With more contacting surface area between the components, the present device provides an upgrade to conventional methods.
The present device, method, kit and system of certain embodiments eliminates the need for the builder, who may be a do-it-your-self builder, for example, to know how to frame a standard door opening or passageway. The present device and method not only makes it easier to construct the opening properly, but it potentially adds strength to the structure as a whole. The components provided in the present device, method and kit may be formed of recycled lumber, laminated wood, compressed lumber, plastics, and metals. The materials, construction, and configuration of the components are not limited to particular materials, constructions or configurations.
The present device, method, system and kit provides to the market a product that provides the materials for assembly of a structural opening, be it a door, passageway, or window. The preferred device, method, system and kit provide pre-cut jack studs. The present kit may be provided as either a knockdown kit or as a pre-assembled unit.
A significant feature of the present device is the utilization of the three different interconnecting elements, and that the components are pre-cut and included in one, easy to assemble kit. The king stud, jack stud, and header each have a distinctive shape that allows them to function properly when used with the correlating pieces that are included in the kit. The distinctive shape of each component provides interlocking of the pieces. In certain embodiments, the kits are of pre-cut, conventional lumber.
In certain embodiments, brackets are included with the kit. The brackets need not be provided for all embodiments of the kit. The brackets can be supplements or optional components that may enhance the structural stability of the structure and the ease of installation of the components. For instance, the brackets could be used in buildings located in hurricane zones. One such bracket could be placed to connect the king and jack studs to the sole plate as already described. Another bracket could connect the king stud to the top plate. A further bracket could connect the header to the king and/or jack studs. In certain embodiments, six brackets are used (three on each side of the wall opening). The brackets are not required in every construction but may be used as desired, for example to enhance stability of the construction, ease of assembly, or for other reasons.
The present apparatus and method in certain embodiments provides solutions to problems that may occur in the field. A kit may be provided according to some embodiments to enable people with a limited construction background to properly construct an opening in the wall of a building. In some embodiments, a person desiring to build or remodel a home or other building is able enter a store, purchase the kit or the components as a product, and install it themselves, free of hassle. In addition to benefits for a do-it-yourself builder, significant advantages are provided by a kit embodiment for people in the professional building field. Because the parts of the kit are pre-fabricated, no cuts need to be made for the frame construction, so that the professional builder will save valuable time on the job site. Secondly, generating an estimate of costs is simpler; each door framing kit will have a predetermined price. Instead of calculating the costs for the loose lumber that is used for the door frame, for example, the builder may simply count the number of framing kits that are needed. This makes estimating jobs far simpler as the cost for the doorways, passageways and window openings becomes standardized. Embodiments that provide the parts in a kit will simplify the building process, saving time, money, and material.
Thus, there are shown and described framing components for doorway, window, and passageway framing in a building. The framing components include king studs, jack studs and a header. The components may be provided separately or may be provided in a kit that is cut to the correct length and sized for the particular construction project.
Although other modifications and changes may be suggested by those skilled in the art, it is the intention of the inventors to embody within the patent warranted hereon all changes and modifications as reasonably and properly come within the scope of their contribution to the art.
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