Patent Publication Number: US-2011067346-A1

Title: Prefabritcated framing member support system and methods for installing a prefabricated framing member support system in a construction application

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application relates to U.S. patent application Ser. No. ______(Atty Docket 26723), filed on the same day as the present patent application, and titled “Prefabricated Framing Member Support System,” the contents of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure is directed generally to prefabricated framing member support systems and methods for installing prefabricated framing member support systems in various construction applications. 
     BACKGROUND 
     Many types of prefabricated horizontal framing components are used in residential and commercial construction. Framing, in construction, is a building technique based around structural members which provide a stable frame to which interior and exterior wall coverings are attached, and support horizontal framing members such as trusses, joists, and dimension lumber, and other framing elements. Prefabricated I-joist framing members are one example of a horizontal framing member. 
     Diagrams of a conventional two-story construction application  100  using framing members are shown in  FIGS. 1 and 2 . In this example, I-joists are shown, but other horizontal framing members could easily be substituted. In this case, the construction application utilizes I-joists in a flooring system. Constructing a flooring system is a long, multi-step, and time-consuming part of any construction process. The first part of the process involves preparing a foundation  102  for the first floor. Then a series of structural layers are installed atop the foundation  102 . In conventional construction applications, these layers may include a sill plate, a rim board, an I-joist attached to the rim board, and floor sheathing. 
     As shown in  FIG. 1 , a foundation  102  is shown with a first sill plate  104  attached to the foundation  102 . A first rim board  106  is then attached to the first sill plate  104  with a toe nail  105 . The attachment of the first sill plate  104  to the first rim board  106  is typically performed on the construction site and requires a significant amount of time. 
       FIG. 3  shows an example of a conventional rim board and sill plate combination  300  produced according to conventional procedures. The rim board and sill plate combination  300  includes a rim board  302  connected to a sill plate  304  with a toe nail  306 . The toe nail  306  is typically driven into the rim board  302  at an angle into the sill plate  304 . 
     Referring back to  FIGS. 1 and 2 , after the first sill plate  104  and the first rim board  106  are connected, a first I-joist  108  is attached and a first floor sheathing  110  is installed. The first story is constructed by attaching a first bottom plate  112  to the first floor sheathing  110 . A first wall member  114  (e.g., a stud) is then attached to the bottom plate  112 . A first top plate  116  is attached to the stud. The second top plate  118  completes the first story. 
     The second story is constructed by attaching a second rim board  120  to the second sill plate (or first double top plate)  118  using a toe nail  119 . The second story is constructed in a similar fashion to the first story by attaching a second I-joist  122  to the second rim board  120  and subsequently installing a second floor sheathing  124 , a second bottom plate  126 , a second wall member  128 , a second top plate  130 , and a second double top plate  132 . 
     Referring to  FIG. 2 , a header  134  is installed on the first story. A header is a horizontal structural member that supports the load over a window or door opening. In conventional two-story construction applications, a header  134  must be used in a doorway  136  to support the load from the structure above it. Trimmers  138  are then installed to support the header  136  and finish the opening for doors and windows. 
     In conventional applications, the first floor sheathing  110  and the second floor sheathing  124  transfer lateral loads into the rim board, into the wall and eventually into the foundation  102 . The toe nail connection between the first and second rim boards  106  and  120  and the first and second sill plates  104  and  118  are weak connections in the structure. It is also the last link to transfer the force to the foundation. Therefore, the loading is often limited by the strength of these connections. 
     In addition to the system described above, horizontal framing members may be connected directly to a beam when the beam spans a large opening such as garage doors. Diagrams of a conventional garage door construction application  400  using I-joists are shown in  FIGS. 4 ,  5 , and  6 . In conventional applications, a foundation  402  is constructed and bracing elements (e,g., panels, shear walls, block walls, concrete, etc.)  404  are attached to the foundation  402 . Beams  406  spanning the distance between the bracing elements  404  and I-joists  408  are attached with joist hangers.  410 . The joist hangers  410  are steel sections shaped like a stirrup, which are specially bent so they can be fastened to the beams  406  in order to provide end support for the I-joists  408 . 
     Thus, there is a need to develop a framing member support system and a method for installing a framing member support system in a construction application that addresses the disadvantages of conventional systems and methods. More specifically, there is a need to develop a framing member support system that is easier to install than current systems. Ideally, such a system would also provide the same or better loading capacity and a higher composite action factor than conventional systems. 
     SUMMARY 
     The following summary is provided for the benefit of the reader only and is not intended to limit in any way the invention as set forth by the claims. The present disclosure is directed generally towards prefabricated framing member support systems and methods for installing prefabricated framing member support systems 
     In one embodiment, a prefabricated framing member support system is provided for use with a horizontal framing member. The horizontal framing member has a top chord, a bottom chord, a web connecting the top chord to the bottom chord and a framing member cross sectional end profile. The prefabricated support system includes an integrated rim board component having a substantially L-shaped cross sectional end profile. The integrated rim board component includes a substantially vertical portion having an inner surface and an outer surface, and a substantially horizontal portion having a top surface and a bottom surface. The integrated rim board component is configured to support the horizontal framing member by arranging the horizontal framing member on the substantially horizontal portion of the integrated rim board component so that the framing member cross sectional end profile makes contact with the inner surface, the bottom chord makes contact with the top surface, and the framing member cross sectional end profile is located in a plane substantially perpendicular to the L-shaped cross-sectional end profile. 
     In some embodiments, the substantially horizontal portion of the integrated rim board component and the substantially vertical portion of the integrated rim board component are connected with chemical or mechanical fasteners. In some embodiments this connection is done to achieve a composite action factor between about 0.8 and about 1.0. In some embodiments, the horizontal framing member is an I-joist; however, other framing members known to those of ordinary skill in the art are within the scope of the disclosure. 
     Further aspects are directed towards methods for installing pre-fabricated framing member support systems. In some embodiments, such methods include the steps of providing a foundation or bracing element, attaching an integrated rim board component according to embodiments of the disclosure to the foundation or bracing element, and attaching a horizontal framing member to the integrated rim board component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure is better understood by reading the following description of non-limitative embodiments with reference to the attached drawings wherein like parts of each of the figures are identified by the same reference characters, and are briefly described as follows: 
         FIG. 1  is a section view of a conventional framing member support system in a first construction application; 
         FIG. 2  is an elevation view of a conventional framing member support system in the first construction application; 
         FIG. 3  is a section view of a conventional rim board and sill plate; 
         FIG. 4  is a section view of a conventional framing member support system in a second construction application; 
         FIG. 5  is an elevation view of a conventional framing member support system in the second construction application; 
         FIG. 6  is a top view of a conventional framing member support system in the second construction application; 
         FIG. 7  is an isometric view of an embodiment of an integrated rim board component according to the disclosure; 
         FIGS. 8 through 13  are section views of embodiments of integrated rim board components according to the disclosure; 
         FIG. 14  is a section view of an embodiment of a framing member support system according to the disclosure in the first construction application; 
         FIG. 15  is an elevation view of an embodiment of a framing member support system according to the disclosure in the first construction application; 
         FIG. 16  is a section view of an embodiment of a framing member support system according to the disclosure in the second construction application; 
         FIG. 17  is an elevation view of an embodiment of a framing member support system according to the disclosure in the second construction application; 
         FIG. 18  is a top view of an embodiment of a framing member support system according to the disclosure in the second construction application; and 
         FIGS. 19 through 21  are isometric views of an integrated rim board according to the disclosure in various loading cases. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure describes to prefabricated framing member support systems and methods for installing prefabricated framing member support systems. Certain specific details are set forth in the following description and  FIGS. 7 through 21  to provide a thorough understanding of various embodiments of the disclosure. Well-known structures, systems, and methods often associated with such systems have not been shown or described in details to avoid unnecessarily obscuring the description of various embodiments of the disclosure. In addition, those of ordinary skill in the relevant art will understand that additional embodiments of the disclosure may be practiced without several of the details described below. 
     The term “wood product” is used to refer to a product manufactured from logs such as lumber (e.g., boards, dimension lumber, headers and beams, timbers, mouldings and other appearance products; laminated, finger jointed, or semi-finished lumber (e.g., flitches and cants); veneer products; or wood strand products (e.g., oriented strand board, oriented strand lumber, laminated strand lumber, parallel strand lumber, and other similar composites). The term “framing member” is used to refer to a structural member designed to support a floor or ceiling load (e.g., trusses, joists, I-joists, dimension lumber, etc.). 
       FIG. 7  is an example of an integrated rim board component  700  according to embodiments of the disclosure. The integrated rim board component  700  has a substantially vertical portion  702  and a substantially horizontal portion  704 . The substantially vertical portion  702  and the substantially horizontal portion connect to form a structure having a substantially L-shaped cross-sectional end profile  706 . 
     Materials used to construct the integrated rim board component  700  may include wood products, metals, composites, or any other suitable material. Specific wood products which may be used include but are not limited to laminated veneer lumber, oriented strand lumber, parallel strand lumber, and plywood. The integrated rim board component  700  may also be constructed from a combination of the materials listed above. 
       FIG. 7  illustrates exemplary dimensions for the integrated rim board component  700 . In this example, the substantially vertical portion  702  may be between approximately 7¼ inches to 24 inches long and between approximately ¾ inch and 3½ inches wide. The substantially horizontal portion may be between approximately 1 inch and 3½ inches long and between approximately 3½ to 7¼ inches wide. The depth D of the substantially vertical portion  702  and the substantially horizontal portion  704  may be between approximately 8¼ to 27½ inches. A person of ordinary skill in the art will understand that the dimensions listed are merely examples and that embodiments of the disclosure contemplate integrated rim board components  700  having dimensions other than those listed. 
     In some embodiments, the integrated rim board component  700  is formed integrally from a single piece of material. In other embodiments, the integrated rim board component  700  may be constructed from two or more separate components which are connected with one or more assembly components (e.g., chemical or mechanical fasteners or connectors).  FIGS. 8 through 13  show examples of integrated rim board components and assembly components according to embodiments of the disclosure. 
       FIGS. 8-10  show examples of mechanical connectors or fasteners. In  FIG. 8 , an integrated rim board component  800  having a substantially vertical portion  802 , and a substantially horizontal portion  804  is shown. In  FIG. 8 , the substantially vertical portion  802  is connected to the substantially horizontal portion  804  with a mechanical connector  806  inserted through the substantially horizontal portion  804  and into the substantially vertical portion  802 . In  FIG. 9 , the substantially vertical portion  802  is connected to the substantially horizontal portion  804  with a mechanical connector  906  located on an inside surface  908  of the integrated rim board  800 . In  FIG. 10 , the substantially vertical portion  802  is connected to the substantially horizontal portion  804  with a mechanical connector  1006  located on an outside surface  1008  of the integrated rim board  800 . Mechanical fasteners or connectors according to the disclosure include but are not limited to nails, brackets, braces, or other known devices for connecting components. 
       FIGS. 11-13  show examples of chemical fasteners or connectors. In  FIG. 11 , a section of the substantially vertical portion  802  and a section of the substantially horizontal portion  804  are manufactured to have finger joints  1106 . The substantially vertical portion  802  may then be connected to the substantially horizontal portion  804  with an adhesive (e.g., glue, epoxy, or another adhesive known to those of skill in the art). As shown in  FIG. 12 , the substantially vertical portion  802  may simply be connected to the substantially horizontal portion  804  with an adhesive on a connection plane  1206 . Alternatively the substantially vertical portion  802  and the substantially horizontal portion  804  may be manufactured as a tongue and groove joint  1306  and subsequently connected with an adhesive. 
     Those of ordinary skill in the art will appreciate that the substantially vertical portion  802  and the substantially horizontal portion  804  may be connected in any manner that is known to a person of ordinary skill in the art. Likewise, the substantially vertical portion  802  and the substantially horizontal portion  804  may be connected using a combination or variation of the methods disclosed herein. 
       FIGS. 14-18  illustrate applications of a two-story construction application using embodiments of framing member support systems according to the disclosure. The basic construction is similar to the conventional methods shown in  FIGS. 1 and 2 . As shown in  FIG. 14 , a foundation  1402  is constructed. Instead of attaching a separate sill plate and rim board, a first integrated rim board component  1404  is attached to the foundation  1402 . In the embodiment shown in  FIG. 14 , the first integrated rim board component  1404  includes a substantially vertical portion  1406  with finger joints connected to a substantially horizontal portion  1408  (e.g., as shown in  FIG. 11 ). It should be noted that other embodiments of integrated rim boards components according to the disclosure may be substituted for the integrated rim board component shown. Because the first integrated rim board component  1404  is prefabricated, there is no need to use the conventional toe nailing procedure described in  FIG. 3 . The elimination of the installation of a separate rim board and sill plate and nailing procedure can reduce construction time, thereby resulting in a cost savings to the builder. 
     After the first integrated rim board component  1404  is attached, a first I-joist  1410  (comprising a top chord  1502 , a bottom chord  1504 , and a web  1506 ) is then attached to the first integrated rim board component  1404 . In this embodiment, the framing member is shown as an I-joist, but other framing members known to those of ordinary skill in the art may be used in place of I-joists. The first integrated rim board component  1404  supports the first I-joist when the first I-joist  1410  if attached to the substantially horizontal portion  1408  so that the web  1506  is arranged in a plane that is substantially perpendicular to the substantially vertical portion  1406  of the first integrated rim board component  1404 . The top chord  1502  and the bottom chord  1504  may be arranged in a plane that is substantially parallel to the substantially horizontal portion  1408  of the first integrated rim board component  1404 . The bottom chord  1504  may make contact with the substantially horizontal portion  1408  and the substantially vertical portion  1406 . The top chord  1502  may make contact with the substantially vertical portion  1406 . The web may make contact with the substantially vertical portion  1406 . 
     After the first I-joist  1410  is set in place a first floor sheathing  1412  is laid. A first bottom plate  1414  may then be connected to the first floor sheathing  1412 . A first wall member  1416  (e.g., a stud) may then be attached to the bottom plate  1414 . This completes construction of the first story. A double top plate may not be required since the integrated rim board component  1404  can be manufactured in long lengths, thus eliminating the splice in the top plate. 
     Instead of installing a top plate as described in the conventional application, a second integrated rim board component  1418  including a substantially vertical portion  1420  and a substantially horizontal portion  1422  may be attached directly to the first wall member  1416 . A second I-framing member  1424  may then be attached to the substantially horizontal portion  1422  of the second integrated rim board component  1418 . Again, the step of nailing a rim board and sill plate together may be eliminated. The second I-framing member  1424  may be connected to the second integrated rim board component  1418  in a manner similar to the one described with respect to the first integrated rim board  1404  and the first I-framing member  1410 . The second story may be completed by installing a second floor sheathing  1426 , a second bottom plate  1428 , a second wall member  1430 , a second top plate  1432 , and a double top plate  1434 . 
     Referring to back to  FIG. 2 , a header  134  is typically installed on the first story in a conventional application. In some embodiments according to the disclosure, a conventional header may be replaced with a more convenient structure. Referring to  FIG. 15 , a trimmer  1436  is shown in place of a header. In embodiments according to the disclosure, a trimmer  1436  may be used in place of a header because the integrated rim board component  1418  supports the load from the structure above it. 
     As discussed earlier, in conventional applications, the toe nail connection between the rim board and the sill plate is the weakest connection in the structure. It is also the last link to transfer the force to the foundation. In some embodiments according to the disclosure, the integrated rim board component may be able to transfer a significantly larger load than a conventional rim board and sill plate combination connected with a toe nail. 
       FIGS. 16-18  show a garage door construction application according to some embodiments of the disclosure. As in conventional applications, a foundation  1602  is constructed and bracing elements (e,g., panels, shear walls, block walls, concrete, etc.)  1604  are attached to the foundation  1602 . Integrated rim board components  1606  having a substantially vertical portion  1608  and a substantially horizontal portion  1610  are then attached to the bracing elements  1604 . As described earlier, in a conventional application (e.g.  FIGS. 4-6 ) beams and joist hanger are typically used to install I-joists. In embodiments according to the disclosure, I-joists  1612  may be attached directly to the integrated rim board components  1606 , thereby eliminating the need for joist hangers. 
     A person of ordinary skill in the art will appreciate that joist support systems according to the disclosure may be used in construction applications no explicitly discussed in this application. When compared to traditional joist support systems, joist support systems according to embodiments of the disclosure may be able to withstand more bending and loading. Thus, it may be desirable to replace a conventional rim board and sill plate combination in a construction application with an integrated rim board component according to embodiments of the disclosure. 
     From the foregoing, it will be appreciated that the specific embodiments of the disclosure have been described herein for purposes of illustration, but that various modifications may be made without deviating from the disclosure. For example, integrated rim board component according to the disclosure may be constructed by other means or using other materials than those disclosed. Additionally, framing member support systems according to the disclosure may be used in construction applications other than those explicitly described and pictured. 
     Aspects of the disclosure described in the context of particular embodiments may be combined or eliminated in other embodiments. For example, chemical fastening methods may be combined with mechanical fastening methods. As another example, construction techniques in some embodiments may be combined with construction techniques in other embodiments. 
     Further, while advantages associated with certain embodiments of the disclosure may have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the disclosure. Accordingly, the invention is not limited except as by the appended claims. 
     Example 
     The following example will serve to illustrate aspects of the present disclosure. The example is intended only as a means of illustration and should not be construed to limit the scope of the disclosure in any way. Those skilled in the art will recognize many variations that may be made without departing from the spirit of the disclosure. 
     When two pieces of material are connected together to form a single piece, their effectiveness to perform as one homogenous piece is dependant on the strength of the connection between the two pieces. In traditional light-framed construction, rim board and sill plates are assumed to act independently i.e. the composite action factor between the two pieces is zero. Therefore, if designing the rim board and sill plate as a bending member, only the modulus of inertia of the rim board is used in design. Calculating composite action is a standard procedure already used when designing floor systems. Typically, floor sheathing nailed to floor joists is assigned a composite action factor of 0.25. If floor sheathing is glued and nailed to floor joists, the assembly is assigned a composite action factor of 0.45. Composite action factors for different configurations can be established and validated through testing. Having a connection made of a rigid adhesive or fasteners designed appropriately, a composite action factor of between 0.8 and 1 is easily achieved. 
     General equation for determining the modulus of inertia (I) for a composite section: 
         I =(CompositeActionFactor)× I   (CompositeRimboard+SillPlate) +(1−CompositeActionFactor)× I   (Rimboard)  
 
     Equation typically used for floor sheathing nailed to floor joists: 
         I =(0.25)× I   (CompositeJoist+Sheathing) +(1−0.25)× I   (Joist)  
 
     Equation that would be used for conventional rim board and sill plate: 
         I =(0)× I   (CompositeRimboard+SillPlate)+( 1−0)× I   (Rimboard)   =I   (Rimboard)  
 
     Equation that would be used for integrated L-shaped section: 
         I =(1)× I   (CompositeRimboard+SillPlate) +(1−1)× I   (Rimboard)   =I   (CompositeRimboard+SillPlate)  
 
       FIGS. 19-21  show an integrated rim board component  1900  (comprised of a substantially vertical portion  1902  and a substantially horizontal portion  1904 ) according to embodiments of the disclosure in various loading cases. Models were used to predict the results of the loading on the integrated rim board component  1900  and on a conventional rim board and sill plate combination connected with a toe nail (not shown under loading, but illustrated in  FIG. 3 ). Table 1 compares the approximate connection capacity of an integrated rim board component  1900  according to embodiments of the disclosure to the approximate connection capacity of a conventional rim board and sill plate combination  300 . All measurements were calculated in pounds per lineal foot. 
     When modeling the conventional rim board and sill plate combination  300 , assumptions about the properties and dimensions were made. The cross sectional dimensions of the rim board  302  were assumed to be 1.25 inches by 11.875 inches. The cross sectional dimensions of the sill plate  304  were assumed to be 1.5 inches by 3.5 inches. Both the rim board  302  and the sill plate  304  were assumed to have a modulus of elasticity of 1,300,000. 
     When modeling the integrated rim board  1900 , similar assumptions were made. The substantially vertical portion  1902  was assumed to have a cross section of 1.25 inches by 11.875 inches. The substantially horizontal  1904  portion was assumed to have a cross section of 1.5 inches by 3.5 inches. In the example modeled, the substantially vertical portion  1902  was connected to the substantially horizontal portion  1904  with glued finger joints (e.g.,  FIG. 11 ). Both the substantially vertical portion  1902  and the substantially horizontal portion  1904  were assumed to have a modulus of elasticity of 1,300,000. 
     In  FIG. 19 , the integrated rim board component  1900  is shown subjected to shear loading as represented by arrows  1906 . In  FIG. 20 , the integrated rim board component  1900  is shown subjected to tension loading as represented by arrows  2006 . In  FIG. 21 , the integrated rim board component  1900  is subjected to shear loading as shown by arrows  2106 . The capacities shown in Table 1 for conventional rim board and sill plate connection are based on conventional nailing schedules. The capacities for the integrated rim board are based on a 400 psi connection strength for Case 1, and 100 psi connection strength for Cases 2 and 3. 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Approximate Connection Capacities (pounds per lineal foot) 
               
            
           
           
               
               
               
               
               
            
               
                   
                   
                 Case 1  
                 Case 2  
                 Case 3  
               
               
                   
                   
                 (FIG. 19) 
                 (FIG. 20) 
                 (FIG. 21) 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                   
                 Conventional Rim 
                 240 
                 Less than 100 
                 Less than 240 
               
               
                   
                 Board and Sill 
                   
                   
                   
               
               
                   
                 Plate 
                   
                   
                   
               
               
                   
                 Integrated Rim 
                 6,000 
                 1,500 
                 1,500 
               
               
                   
                 Board 
               
               
                   
                   
               
            
           
         
       
     
     According to the results, embodiments of integrated rim board components  1900  according to the disclosure are expected to exhibit higher connection capacities than conventional rim board and sill plate combinations  300  in all three loading cases, Although the modeling for Table 1 was based on an integrated rim board component  1900  constructed using glued finger joints, integrated rim board components having different configurations are expected to show similar results. 
     In addition to estimating connection capacity, the models described above were used to estimate bending properties for embodiments of integrated rim board components  1900  according to the disclosure and conventional rim board and sill plate combinations  300 . Modulus of inertia and moment capacity were calculated and the results are presented in Table 2. 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 Approximate Bending Properties 
               
            
           
           
               
               
               
               
            
               
                   
                   
                 Modulus of  
                 Moment  
               
               
                   
                   
                 Inertia (in 4 ) 
                 Capacity( ft-lb) 
               
               
                   
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Conventional Rim  
                 174 
                  5,690 
               
               
                   
                 Board and Sill Plate 
                   
                   
               
               
                   
                 Integrated Rim Board 
                 349 
                 11,880 
               
               
                   
                   
               
            
           
         
       
     
     According to the results, embodiments of integrated rim board components  1900  according to the disclosure are expected to exhibit both a higher modulus of inertia and a higher moment capacity than conventional rim board and sill plate combinations  300 .