Abstract:
A hold down system for a building wall comprises a first rigid member and a second rigid member, the second rigid member being vertically spaced apart from the first rigid member, the first rigid member is supported on a horizontal member of a stud wall, the first and second rigid members including first and second openings, respectively; a tie-rod with a lower end portion for being anchored to an anchorage, the tie-rod extending transversely through the first and second openings, the tie-rod dividing the first and second rigid members into a first lateral section on one side of the tie-rod and a second lateral section on a diametrically opposite side of the tie-rod; first support and second support disposed between the first and second rigid members, the first support being disposed in the first lateral section, the second support being disposed in the second lateral section, the tie-rod extending through the first and second rigid members outside of the first support or the second support; and a nut threaded to the tie-rod, the nut exerting pressure on the second rigid member to place the tie rod under tension loading, the tension loading is transferred by the second rigid member to the first and second supports to subject the first and second supports to compression loading, thereby causing the first rigid member to press on the horizontal member of the stud wall via the first and second lateral sections of the first rigid member, thus distributing the compression loading.

Description:
RELATED APPLICATION 
       [0001]    This is a nonprovisional application of provisional application Ser. No. 62/219,005, filed Sep. 15, 2015, hereby incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention is generally directed to a tension hold down system used in walls in light frame construction to resist uplift and to compensate for wood shrinkage in wood frame construction and compression loading. 
       SUMMARY OF THE INVENTION 
       [0003]    The present invention provides a hold down system for a building wall, comprising a first rigid member and a second rigid member, the second rigid member being vertically spaced apart from the first rigid member, the first rigid member is supported on a horizontal member of a stud wall, the first and second rigid members including first and second openings, respectively; a tie-rod with a lower end portion for being anchored to an anchorage, the tie-rod extending transversely through the first and second openings, the tie-rod dividing the first and second rigid members into a first lateral section on one side of the tie-rod and a second lateral section on a diametrically opposite side of the tie-rod; first support and second support disposed between the first and second rigid members, the first support being disposed in the first lateral section, the second support being disposed in the second lateral section, the tie-rod extending through the first and second rigid members outside of the first support or the second support; and a nut threaded to the tie-rod, the nut exerting pressure on the second rigid member to place the tie rod under tension loading, the tension loading is transferred by the second rigid member to the first and second supports to subject the first and second supports to compression loading, thereby causing the first rigid member to press on the horizontal member of the stud wall via the first and second lateral sections of the first rigid member, thus distributing the compression loading. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  is a perspective view of a building wall using a hold down system embodying the present invention. 
           [0005]      FIG. 2  is an enlarged perspective view of an anchor assembly in  FIG. 1 . 
           [0006]      FIG. 3  is a perspective view of a slack absorber assembly of the hold down system in  FIG. 1 . 
           [0007]      FIG. 4  is a cross-sectional view along a longitudinal axis of one of the expansion devices shown in  FIG. 3 . 
           [0008]      FIG. 5  is perspective view of a retainer ring shown in  FIG. 4 . 
           [0009]      FIG. 6  is a cross-sectional of the washers shown in  FIG. 3 . 
           [0010]      FIG. 7  is a perspective view of a building wall reinforced by a hold down system embodying the present invention. 
           [0011]      FIG. 8  is a perspective view of a slack absorber assembly of the hold down system of  FIG. 7 . 
           [0012]      FIG. 9  is a cross-sectional view of the slack absorber assembly of  FIG. 8 . 
           [0013]      FIG. 10  is a perspective view of a slack absorber assembly of the hold down system of  FIG. 7 . 
           [0014]      FIGS. 11-13  are alternative embodiments of the hold down system shown in  FIG. 7 . 
           [0015]      FIG. 14  is a perspective view of a cross-member used in the system shown in  FIG. 13 . 
           [0016]      FIG. 15  is a cross-sectional view along line  15 - 15  in  FIG. 14 . 
           [0017]      FIG. 16  is a perspective view of a building wall reinforced by a hold down system embodying the present invention. 
           [0018]      FIG. 17  a perspective view of a slack absorber assembly in the hold down system of  FIG. 16 . 
           [0019]      FIG. 18  is an alternative location of the slack absorber assembly shown in  FIG. 17 . 
           [0020]      FIG. 19  is a perspective view of a building wall using a hold down system embodying the present invention. 
           [0021]      FIG. 20  is a perspective view of a portion of the hold down system of  FIG. 19 . 
           [0022]      FIG. 21  is a perspective view of a slack absorber assembly in the hold down system shown in  FIG. 19 . 
           [0023]      FIG. 22  is a cross-section view of the slack absorber assembly of  FIG. 21 . 
           [0024]      FIG. 23  is a perspective view of a building wall using a hold down system embodying the present invention. 
           [0025]      FIG. 24  is perspective view of a slack absorber assembly in the hold down system in  FIG. 23 . 
           [0026]      FIGS. 25 and 26  are a perspective view of a bracket in the slack absorber assembly in the hold down system in  FIG. 24 . 
           [0027]      FIG. 27  is a top view of the bracket shown in  FIGS. 25-26 . 
           [0028]      FIGS. 28 and 29  are perspective views of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0029]      FIG. 30  is a perspective view of the washers used in the slack absorber assembly shown in  FIG. 28 . 
           [0030]      FIG. 31  is a bottom view of  FIG. 30 . 
           [0031]      FIG. 32  is a cross-sectional view of  FIG. 30 . 
           [0032]      FIGS. 33-35  are alternative embodiments of the washers shown in  FIG. 30 . 
           [0033]      FIG. 36  is a perspective view of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0034]      FIG. 37  is a cross-sectional view of the slack absorber assembly shown in  FIG. 36 . 
           [0035]      FIG. 38  is a perspective view of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0036]      FIG. 39  is a perspective view of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0037]      FIG. 40  is a cross-sectional view of the slack absorber assembly shown in  FIG. 39 . 
           [0038]      FIG. 41  is a perspective view of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0039]      FIG. 42  is a cross-sectional view of the slack absorber assembly shown in  FIG. 41 . 
           [0040]      FIG. 43  is an assembly view of the slack absorber assembly shown in  FIG. 41 . 
           [0041]      FIG. 44  is a perspective view of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0042]      FIG. 45  is an assembly view of the slack absorber assembly shown in  FIG. 44 . 
           [0043]      FIG. 46  is a cross-sectional view of the slack absorber assembly shown in  FIG. 45 . 
           [0044]      FIG. 47  is a perspective view of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0045]      FIG. 48  is a cross-sectional view of the slack absorber assembly shown in  FIG. 47 . 
           [0046]      FIG. 49  is a side elevational view of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0047]      FIG. 50  is a cross-sectional view of the slack absorber assembly shown in  FIG. 49 . 
           [0048]      FIG. 51  a perspective view of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0049]      FIG. 52  is cross-sectional view of a split nut assembly shown in  FIG. 51 . 
           [0050]      FIG. 53  is a top perspective view of the split nut assembly shown in  FIG. 52  with the cover removed. 
           [0051]      FIG. 54  is perspective view of a slack absorber assembly used in a hold down system in any of the building walls shown above. 
           [0052]      FIG. 55  is an illustration of various combinations of the slack absorber assemblies disclosed herein. 
           [0053]      FIG. 56  is cross-sectional view of a slack absorber assembly shown in  FIG. 10  using a split nut assembly. 
           [0054]      FIG. 57  is an assembly view of the split nut assembly shown in  FIG. 56 . 
           [0055]      FIG. 58  is a cross-sectional view of a slack absorber assembly embodying the present invention. 
           [0056]      FIG. 59  is a perspective view of a slack absorber assembly embodying the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0057]    A two-story building wall  2  using a hold down system  4  embodying the present invention is disclosed in  FIG. 1 . The building wall  2  includes a base plate  6  supported by a concrete foundation  8 , a plurality of studs  10  attached to the base plate  6 , a double top plate  12  attached to the studs  10 , a plurality of floor joists (not shown, but see  FIGS. 16 and 17 ) supported on the double top plate  12 , a subfloor  14  supported on the floor joists, a bottom plate  16  supported on the subfloor  14 , a plurality of studs  18  attached to the bottom plate  16 , a double top plate  20  attached to the studs  18  and wall sheathing  22  attached to the studs  10  and  22 , the bottom plates  6  and  16 , and the top plates  12  and  20 . 
         [0058]    The hold down system  4  includes a tie rod  24  attached at one end to an anchor assembly  26  embedded in the concrete foundation  8 . The other end of the tie rod  24  is attached to a slack absorber assembly  28  supported by the top plate  20 . The tie rod  24  is disposed within the wall  2 , extending through openings in the base plates  6  and  16  and the top plates  12  and  20 . The tie rod  24  may made of multiple sections joined together into one with couplers  30 . 
         [0059]    Referring to  FIG. 2 , the anchor assembly  26  includes an anchor support  32 , an anchor rod  34  attached to the anchor support  32  and an anchor body  36  in the form of a hex nut threaded to the anchor rod  34 . The anchor rod  34  extends outside the foundation  8  through the base plate  6  and connects to the tie rod  24  by means of the coupler  30 . The coupler  30  is threadedly attached to the anchor rod  34  and the tie rod  24 . 
         [0060]    The support  32  is described in U.S. Pat. No. 8,943,777, herein incorporated by reference. Other standard supports may also be used. 
         [0061]    The anchor body  36  may be of any shape that is suitable for embedment in concrete and able to resist the uplift and shear loads of the building wall  2  during a storm, hurricane or earthquake. Other examples of the anchor body  36  are described in U.S. Pat. Nos. 8,943,777 and 9,097,001, hereby incorporated by reference. 
         [0062]    Referring to  FIG. 3 , the slack absorber assembly  28  includes a bottom rigid member  38  supported by the top plate  20 , a left side expansion device  40 , a center expansion device  42 , a right side expansion device  44 , a top rigid member  46 , a male washer  48 , a female washer  50  and a nut  52 . The nut  52  is threaded to an end portion  54  of the tie rod  24  to keep the expansion devices  40 ,  42  and  44  between the rigid members  38  and  46 . Each of the devices  40 ,  42  and  44  includes a spring  56  under compression to tend to urge the top rigid member  46  away from the bottom rigid member  38 , thereby to take up any slack that may later develop in the tie rod  24  due to later shrinkage of the wall  2  due to settling, drying, etc. The springs  56  advantageously keep the tie rod  24  under tension. Removable clips  58  are used to keep the springs  56  from expanding during installation and are removed after installation of the devices  40 ,  42  and  44  to activate the springs  56 . The devices  40 ,  42  and  44  are described in U.S. Pat. No. 7,762,030, hereby incorporated by reference. 
         [0063]    The expansion devices  40 ,  42  and  44  provide support to the top rigid member  46  and transfer the load to the bottom rigid member  38 . The load from the nut  52  as it applies tension load on the tie rod  24  is advantageously distributed to the expansion devices  40 ,  42  and  44  and thence to the bottom rigid member  38 . The expansion devices  40  and  44  advantageously carry load offset from the tie rod  24 , thereby distributing the load over a larger area. The load is distributed over three expansion devices, thereby allowing each of the expansion devices  40 ,  42  and  44  to be of smaller sizes that will fit in the limited space inside a wall than if a single expansion device were used. 
         [0064]    Referring to  FIG. 4 , the expansion device  40  is shown in cross-section, which also applies to the other expansion devices  42  and  44 . Accordingly, only the expansion device  40  will be described. 
         [0065]    The expansion device  40  includes an inner cylindrical member  60 , which is disposed within and slidable in an upward direction relative to an outer cylindrical member  62  under the action of the spring  56 . The inner cylindrical member  60  includes an axial opening  61 . The inner and cylindrical members  60  and  62  are lockable relative to one another in a downward direction of the inner cylindrical member  60  to prevent the spring  58  from compressing to its prior position after the spring  58  has expanded to take up the slack in the tie-rod  24 . 
         [0066]    A retainer ring  64  is attached to an upper portion of the inner cylindrical member  60  to keep the spring  58  wound around the outer cylindrical member  62  at one end. The spring  58  is wound around an annular recess  66  around the outer cylindrical member  62  and an annular shoulder  68  at one end of the recess  66  keeps the spring  56  in place. The spring  58  is preferably helical. The removable clip  58  advantageously prevents movement between the inner cylindrical member  60  and the outer cylindrical member  62  during installation of the expansion device  40 . 
         [0067]    The retainer ring  64  includes flexible fingers  70  that are received in an annular recess  72  at the upper end portion of the inner cylindrical member  60 . 
         [0068]    The inner cylindrical member  60  and the outer cylindrical member  62  have opposing cylindrical walls  74  and  76 , respectively, with corresponding receiving volumes  78  and  80 , respectively. A resilient member  82  is disposed between the opposing cylindrical walls  74  and  76  and is biased to occupy one of the receiving volumes  80 . The receiving volumes  78  and  80  are configured in cross-section such that when the inner cylindrical member  60  is moved upwardly, the resilient member  82  is shifted into and fully received in one of the receiving volumes  78 . The receiving volumes  78  and  80  are further configured in cross-section such that when the inner cylindrical member  60  is subjected to a downward force, the resilient member  82  is only partially received within one of the receiving volumes  80  to preclude movement of the inner cylindrical member  60 . The resilient member  82  is preferably a split ring. 
         [0069]    The retainer ring  64  is preferably made of plastic with the fingers  70  disposed inwardly and distributed around the opening  84 . When installing the retainer ring  64  to the inner cylindrical member  60 , the retainer ring  64  is pushed downwardly at the upper end of the inner cylindrical member  60 . The fingers  70  will flex and bend back into respective recesses  86  as the retainer ring  64  travels downwardly and then spring back and engage the annular recess  72  when they get past the upper edge  88  of the inner cylindrical member  60 . 
         [0070]    Referring to  FIG. 6 , the male washer  48  includes a spherical convex top surface  90  that mates with a bottom spherical concave surface  92  of the female washer  50 . The washer  50  has an opening  94  configured for the diameter of the tie rod  24 . The washer  48  has an opening  96  that is larger than the opening  94  to allow the washer  50  to move to one side or the other side when the tie rod  24  is not installed perfectly vertical. The mating surfaces  90  and  92  advantageously remain in contact as the top rigid member  46  rises unevenly to the left or to the right due to an uneven expansion of one of the expansion devices  40  and  44 . The washers  48  and  50  advantageously remain flat with the top rigid member  46  and the nut  52  even when the tie rod  24  is not perfectly vertical or perpendicular with the top plates  20 , and hence the bottom rigid member  38  and the top rigid member  46 . The bottom rigid member  38  and the top rigid member  46  also have oversize openings (through which the tie rod  24  extends) similar to the opening  96  to accommodate the tie rod  24  not being perfectly vertical. 
         [0071]    The opening  94  of the washer  50  may be threaded to mate with the thread on the tie rod  24  to advantageously provide the function of the nut  52  so that the nut  52  can be eliminated to reduce the number of components, thereby saving cost and simplifying inventory. The washer  50  may be provided with hexagonal flat surfaces in the manner of a standard nut for use with a wrench or other standard tightening tool. 
         [0072]    The bottom rigid member  38  and the top rigid member  46  are preferably flat and planar and made of metal. The bottom rigid member  38  and the top rigid member  46  may also be made of hollow metal, such as shown in  FIGS. 14 and 39 . It should be understood that the top rigid member  46  does not have to be a separate unit but may be built into the expansion devices  40  and  44 . Similarly, the bottom rigid member  38  may be part of the wall structure that provides the function of a bearing surface so that it does not have to be provided separately, such as a tall wood block as shown in  FIG. 11  or a metal cross member as shown in  FIGS. 12 and 13 . It should be understood that the bottom rigid member  38  and the top rigid member  46  are intended to mean any structure that provides a bearing surface, whether separate or integrated with the expansion devices. 
         [0073]    Referring to  FIG. 7 , a three-story building wall  98  is disclosed. The wall  98  is similar to the wall  2  of  FIG. 1 , but with the addition of a third story. A bottom plate  100  is disposed on a subfloor  102 . Double top plates  104  are secured to the top ends of studs  106 . Roof truss  108  is supported on top of the double top plates  104 . 
         [0074]    A hold down system  110  is used to reinforce the building wall  98  against uplift and shear forces. The system  110  includes the anchor assembly  26 ; the tie rod  24  connected to the anchor assembly  26 ; a slack absorber assembly  112  connected to the tie rod  24  to take up any slack that may develop later in the tie rod  24 ; a tie rod  114  connected to the tie rod  24  through a coupler  116 ; a slack absorber assembly  118  connected to the tie  114  to take up any slack that may develop later in the tie rod  114 ; a tie rod  120  connected to the tie rod  114  with a coupler  122 ; and the slack absorber assembly  28 . 
         [0075]    Referring to  FIG. 8 , the slack absorber assembly  112  is preferably disposed on a bearing plate  124 , which is supported by the bottom plate  16 . The slack absorber assembly  112  includes a left side expansion device  126 , a right side expansion device  128 , a bottom rigid member  130 , a top rigid member  132 , threaded rods  134  that extend through openings  136  in the top rigid member  132  and threadedly attached to threaded openings  137  in the bottom rigid member  130 . The threaded rods  134  are secured to the top rigid member  132  with nuts  138 . The slack absorber assembly  112  uses the male washer  48  and the female washer  50  in the same manner as the slack absorber assembly  44 . The nut  52  attaches the slack absorber assembly  112  to the tie rod  24 . 
         [0076]    The tie rod  114  is smaller in diameter than the tie rod  24  due to the decreased load above the slack absorber assembly  112 . The smaller size tie rod  114  advantageously provides for a cost savings. The coupler  116  includes a larger threaded bore at one end for threaded attachment to the tie rod  24  and a smaller threaded bore at the other end for threaded attachment to the tie rod  114 . The coupler  116  is described in application Ser. No. 13/424,082, hereby incorporated by reference. 
         [0077]    Because the center expansion device  42  is not used, the axial opening  61  through the inner cylindrical member  60  does not have to be sized to accommodate the diameter of the tie rod  24 , advantageously providing the flexibility of reducing the overall diameter of the expansion devices to fit within the wall cavity. The overall diameter of the expansion device  40  or  42  is advantageously independent of the diameter of the tie rod  24 , since the expansion device  40  or  42  does not surround the tie rod  24  (i.e., the tie rod  24  does not pass through the expansion device  40  or  42 ). For example, the diameter of the axial opening  61  of the inner cylindrical member  60  can be smaller than the diameter of the tie rod  24 , or the axial opening  61  does not have to be provided so that the inner cylindrical member  60  can be made solid. The outside diameter of the inner cylindrical member  60  or the diameter of the axial opening of the outer cylindrical member  62  can even be smaller than the diameter of the tie rod  24 . Further, the size of the rods  134  is also irrelevant of the size of the tie rod  24  or  114 . 
         [0078]    Referring to  FIG. 9 , the expansion devices  126  and  128  are similar to any one of the expansion devices  40 ,  42  and  44  and work in the same way. The expansion devices  126  and  128  are described in U.S. Pat. No. 7,762,030, herein incorporated by reference. After installation, the nuts  138  are removed to allow the top rigid member  132  to move upwardly under the action of the springs  56  when a slack develops in the tie rod  24 . The openings  136  are large enough to allow relative motion between the rod  134  and the top rigid member  132 . The removable clips  58  shown in  FIG. 3  are not used, since the threaded rods  134  and the nuts  134  provide the same function of holding the compressed springs  56  in place prior to installation. The retainer rings  140  are respectively attached to the inner cylindrical member  60 . When the springs  56  expand due to slack in the tie rod  24 , inner cylindrical member  60  moves upwardly under the action of the spring  56  while the outer cylindrical members  62  are pressed by the spring  56  against the bottom rigid member  130 . 
         [0079]    The expansion devices  126  and  128  advantageously carry load offset from the tie rod  24 , thereby distributing the load over a larger area. The load is distributed over two expansion devices, thereby allowing each of the expansion devices  126  and  128  to be of smaller sizes that will fit in the limited space inside a wall than if a single expansion device were used. 
         [0080]    Referring to  FIG. 10 , the slack absorber assembly  118  includes the left expansion device  40  and the right expansion device  44 . The slack absorber assembly  118  is similar to the slack absorber assembly  28 , except that the center expansion device  42  is not used. The removable clips  58  are removed after installation of the slack absorber assembly  118  to allow the springs  56  to expand to take up any slack in the tie rod  114 . The tie rod  120  is smaller in diameter than the tie rod  114  due to the smaller load above the slack absorber assembly  118 . The coupler  122  has a smaller threaded bore at one end for attachment to the tie rod  120  and a larger threaded bore at the other end for threaded attachment to the tie rod  114 . The opening  142  in the bottom rigid member  38  is advantageously oversized or elongated in the lengthwise direction of the bottom rigid member  38  to allow the tie rod  114  to be off the vertical to the left or to the right to accommodate a less perfect installation. Because the center expansion device  42  is not used, the axial opening  61  through the inner cylindrical member  60  does not have to be sized to accommodate the diameter of the tie rod  114 , advantageously providing the flexibility of reducing the overall diameter of the expansion devices to fit within the wall cavity. 
         [0081]    Referring to  FIG. 11 , the building wall  98  is shown with a modified hold down system  114 . The slack absorber assembly  28  disposed on the double top plate  104  shown in  FIG. 7  has been moved to a position between the bottom plate  100  and the top double plate  104 . Reinforcement or jack studs  146  are attached to the studs  106  with nails or screws. The reinforcement studs  146  have bottom ends  148  engaging the bottom plate  100  and top ends  150  supporting a horizontal cross member  152 . The cross member  152  is advantageously made of a block of wood which is taller than its width. The slack absorber assembly  28  is supported by the cross member  152 . 
         [0082]    Referring to  FIG. 12 , the wooden cross member  152  may be replaced with a solid metal cross member  154 . 
         [0083]    Referring to  FIG. 13 , the wooden cross member  152  may be replaced with a structural hollow metal cross member  156 , as described in U.S. Pat. No. 9,097,000, incorporated herein by reference. The cross member  156  includes a top wall  158  and a parallel bottom wall  160  connected together with outside vertical walls  162  and inside vertical walls  164 . Opening  166  in the top wall  158  and opening  168  in the bottom wall  160  allow the tie rod  120  to extend through the cross-member  156 . The vertical walls  162  and  164  join with the top wall  158  and the bottom wall  160  with radius surfaces  170 . 
         [0084]    Referring to  FIG. 16 , the wall  98  is shown with floor joists  172  disposed between the subfloor  14  and the double top plate  12 . Floor joists  174  are also shown disposed between the subfloor  102  and the double top plate  20 . A ring joist  176  is disposed between the subfloor  14  and the double top plate  12 . Another ring joist  178  is disposed between the subfloor  102  and the double top plate  20 . 
         [0085]    Referring to  FIG. 17 , blockings  180  are disposed between the subfloor  14  and the double top plate  12 . The blockings  180  advantageously provide additional support to the bottom plate  16  on which the slack absorber assembly  112  is disposed. The load from the slack absorber assembly  112  is advantageously transferred through the blockings  180  to the studs  10  below. 
         [0086]    Referring to  FIG. 18 , the slack absorber assembly  118  is disposed on the double top plate  20 . Blockings  182  are provided on each side of the slack absorber assembly  118 . The blockings  182  are disposed between the subfloor  102  and double top plate  20 . The location of the slack absorber assembly  118  on the double plate  20  is an alternative location to the bottom plate  100 . 
         [0087]    Referring to  FIG. 19 , the building wall  98  is reinforced with a hold down system  184 , which includes a slack absorber assembly  186  disposed on the bottom plate  16 . The slack absorber assembly  186  advantageously takes up slack from the tie rod  24  and the tie rods  114  and  120 . An end portion of the tie rod  20  is tied to the double top plate  104  with a bearing plate  188  and a nut  190 , as shown in  FIG. 20 . 
         [0088]    Referring to  FIGS. 21 and 22 , the slack absorber assembly  186  is similar to the slack absorber assembly  112 , shown in  FIG. 9 , except that the bottom rigid member  130  and the threaded rods  134  have been extended and threadedly attached to respective threaded bores  192  in the bearing plate  124 . The nuts  138  are screwed upwardly after installation a sufficient distance above the top rigid member  132  so as not to interfere with upward movement of the top rigid member  132  as the expansion devices  126  and  128  expand upwardly to take up any slack in the tie rod  24 . 
         [0089]    The upper ends  194  of the threaded rods  134  are fixed to opposite ends of a member  196  through openings  198  and nuts  200 . An expansion device  202  identical to the expansion device  40  shown in  FIG. 4  is attached to one end of the tie rod  114  that extends through an opening  204  of the member  196 . The expansion device  202  advantageously takes up any slack that may develop in the tie rod  114 . A nut  206  secures the expansion device  202  to the member  196 . 
         [0090]    Referring to  FIG. 23 , the building wall  98  is reinforced with a hold down system  206 , which includes the anchor assembly  26 , the tie rod  24  and the slack absorber assembly  112 , as shown in  FIG. 7 ; a tie rod  208  connected to the tie rod  24 , a slack absorber assembly  210  with tie rods  212  secured to a bracket  214  wrapped around the roof truss  108 . 
         [0091]    The slack absorber assembly  210  is the same as the slack absorber assembly  186 , except that the threaded rods  134  are replaced with the tie rods  212  and the member  196  and expansion device  206  are not used. 
         [0092]    Referring to  FIG. 24 , the tie rods  212  are threaded to threaded bores  192  (see  FIG. 22 ) in the bearing plate  124 . The tie rods  212  extend through openings in the double top plate  104  and are secured to the bracket  214  with nuts  216 . The roof truss  108  is disposed transversely to the double top plate  104  and includes an inclined member  216  and a horizontal member  218 . The roof truss  108  is of standard design. 
         [0093]    Referring to  FIGS. 25, 26 and 27 , the bracket  214  includes a U-shaped portion  220  and side flange portions  222 . The U-shaped portion  220  is configured to fit over the inclined member  216 . The flange portions  222  each includes an elongated or slotted opening  224  to allow the tie rods  212  to extend through the respective openings  224  at an angle with respect to flange portions  222 . The openings  224  are disposed on raised arched portions  226  to advantageously allow the nuts  216  to be tightened sufficiently when the nuts  216  are an angle with respect to the flanges  222 . 
         [0094]    The U-shaped portion  220  includes a preferably planar or flat side wall portions  228  that are parallel to each other and a planar base wall portion  230  perpendicular to the side wall portions  228 . The U-shaped portion  220  is configured to fit over and to the sides of the inclined member  216 . The flange portions are preferably perpendicular to the side portions  228  and parallel to the base portion  230 . The bracket  214  is preferably made from sheet metal. 
         [0095]    Referring to  FIGS. 28 and 29 , a slack absorber assembly  231  is disclosed. The slack absorber assembly  231  is similar to the slack absorber assembly  28  shown in  FIG. 3 , except that the center expansion device  42  is not used. All other parts are designated with the same reference numerals. The slack absorber assembly  231  is advantageously used where the expected load is less than the expected load for the slack absorber assembly  28  such that the center expansion device  42  is not used. Because the center expansion device  42  is not used, the axial opening  61  through the inner cylindrical member  60  does not have to be sized to accommodate the diameter of the tie rod  234 , advantageously providing the flexibility of reducing the overall diameter of the expansion devices to fit within the wall cavity. Openings  232  in the bottom rigid member  38  and the top rigid member  46  are oversized with respect to the diameter of the tie rod  234  to allow the tie rod  234  to be off the vertical (due to less than perfect vertical installation) when extending through the openings  232 . 
         [0096]    Referring to  FIGS. 30, 31 and 32 , the top rigid member  46  shown in  FIG. 28  may be replaced with a top bearing  236  and the male washer  48  with male washer  238 . The top rigid member  236  has an elongated opening  240 , which receives a cylindrical extension portion  242  of the male washer  238 . The male washer  238  has an annular flange  244  that sits on a top surface  246  of the top rigid member  236 . A gap  248  on each side of the extension portion  242  allows the extension portion  242  to move in either direction to advantageously accommodate the tie rod  234  that may be a few degrees off from the vertical. The elongated opening  240  also allows the top rigid member  236  to be off the horizontal due to uneven expansion of the expansion devices  42  and  44  while maintaining maximum surface contact between the washers  50  and  238  and top rigid member  236 . An opening  250  through the male washer  238  is oversized with respect to the diameter of the tie rod to allow the tie rod within the opening to be off from the vertical by a few degrees. The opening of the washer  50  may be threaded to mate with the thread of the tie rod  234  to advantageously eliminate the use of the nut  52 , thereby reducing the number of components to save cost and simplify inventory. The washer  50  may be provided with hexagonal flat surfaces in the manner of a standard nut for use with a wrench or other standard tightening tool. 
         [0097]    Referring to  FIGS. 33 and 34 , the top rigid member  46  shown in  FIG. 28  may be replaced with a top rigid member  252  and a centering washer  254 . The top rigid member  252  has a concave surface  256  around the periphery of an opening  258 . The centering washer  254  has a corresponding convex surface  260  around the periphery of an opening  262 . The surfaces  256  and  260  are preferably spherical to allow the centering washer  254  to swivel over the opening  258 . The opening  258  is oversized with respect to the diameter of the tie rod to allow the tie rod within the opening to be off from the vertical by a few degrees. 
         [0098]    Referring to  FIG. 35 , the top rigid member  252  may be provided with a convex surface  264  around the periphery of the opening  258  instead of the concave surface  260  shown in  FIG. 34 . The convex surface  264  rises above the top surface  266  of the top rigid member  252 . The centering washer  254  may be provided with a concave surface  268  instead of the convex surface  260  shown in  FIG. 34 . The surfaces  264  and  268  are preferably spherical surfaces to advantageously allow swiveling motion of the centering washer  254  around the opening  258 . 
         [0099]    The opening  262  of the washer  254  may be threaded to mate with the thread of the tie rod  234  to advantageously eliminate the use of the nut  52 , thereby reducing the number of components to save cost and simplify inventory. The washer  254  may be provided with hexagonal flat surfaces in the manner of a standard nut for use with a wrench or other standard tightening tool. 
         [0100]    Referring to  FIG. 36 , a slack absorber assembly  270  is disclosed that is similar to the slack absorber assembly  128  shown in  FIGS. 8 and 9 , except that the bottom rigid member  130  is replaced with a hollow rigid member  272 . The hollow rigid member  272  is structurally the same as the cross-member  156  shown in  FIG. 14  so that the same reference numerals are used to designate the various portions of the hollow rigid member  272 . 
         [0101]    Referring to  FIG. 37 , the threaded rods  134  are threaded in threaded openings  274 . The nuts  134  keep the slack absorber assembly  270  inactive until after installation at which time the nuts  134  are removed. 
         [0102]    Referring to  FIG. 38 , a slack absorber assembly  276  is disclosed. The slack absorber assembly  276  is similar to the slack absorber assembly  270  shown in  FIG. 36 , except that the top rigid member  132  is replaced with a hollow rigid member  278 , which is structurally the same as the hollow rigid member  272  except for size. Accordingly, the hollow rigid member  278  will not be described further. 
         [0103]    Referring to  FIG. 39 , a slack absorber assembly  278  is disclosed. The slack absorber assembly  278  is similar to the slack absorber assembly  118  shown in  FIG. 10 , except that the top rigid member  46  is replaced with a hollow rigid member  280 , which is tubular and rectangular in cross-section. The hollow rigid member  280  has a top wall  282 , a bottom wall  284  and side walls  286 . Referring to  FIG. 40 , the depth of the hollow rigid member  280  is about the same width as the expansion devices  40  and  44 . The hollow rigid member  280  is advantageously narrow so that the force from the male washer  48  is transferred laterally to the side walls  286  in the shortest possible distance. 
         [0104]    Referring to  FIGS. 41, 42 and 43 , a slack absorber assembly  288  is disclosed. The slack absorber assembly  288  includes left and right expansion devices  290  disposed on either side of a tie rod  292 . Each expansion device  290  works by relative rotational movement between an outer cylindrical member  294  and an inner cylindrical member  296  due to an unwinding of a torsion spring  298 . The spring  298  under compression is effective to cause relative rotational motion between the inner cylindrical member  296  and the outer cylindrical member  294 . The inner cylindrical member  296  has outer thread  300  that engages with an inner thread  302  of the outer cylindrical member  294 . The inner cylindrical member  296  has a flange portion  304  with a radial hole  306  for securing one end of the torsion spring  298 . Similarly, the outer cylindrical member  294  has a radial hole  308  for securing the opposite end of the torsion spring  298 . 
         [0105]    A removable clip  310  is used to prevent relative movement between the inner cylindrical member  296  and the outer cylindrical member  294  during installation. Leg portions  312  are received within circumferential groove  314  at the bottom portion of the inner cylindrical member  296  and extend past the bottom edge  316  of the outer cylindrical member  294 , thus preventing relative movement between the inner cylindrical member  296  and the outer cylindrical member  294 . 
         [0106]    Bolts  318  attach the expansion devices  290  to the top rigid member plate  46 . Each of the bolt  318  is threaded to the respective inner thread  320  of each inner cylindrical member  296 , thereby fixing the inner cylindrical member  296  to the top rigid member  46 . 
         [0107]    Once the slack absorber assembly  288  is installed in place at a location within the building wall  98 , the clips  310  are removed. The outer cylindrical member  294  is then free to rotate in an unscrewing manner from the inner cylindrical member  296  due to the action of the torsion spring  298  when a slack develops in the tie rod  292 . The unscrewing action of the outer cylindrical member  294  extends the length of the expansion device  290 , thereby absorbing any slack that develops in the tie rod  292 . The inner cylindrical member  296  stays fixed to the top rigid member  46  while the outer cylindrical member  294  is rotatable in the unscrewing direction when a slack develops in the tie rod  292 . 
         [0108]    Since the expansion devices  290  are disposed outside the tie rod  292  (i.e., the tie rod does not enter and extend through the expansion devices), the respective diameters of the components of the expansion devices  290  can be sized without regard to and is independent of the diameter of the tie rod  292 , and vice versa. For example, the diameter of the tie rod  292  is shown as being larger than the diameter of the inner thread  320  of each inner cylindrical member  296 . In this case, the diameter of the tie rod  292  can be chosen to be large enough to act as a compression member to take up a compression load. Further, the size of the bolts  318  is also irrelevant of the size of the tie rod  292 . 
         [0109]    The expansion devices  290  advantageously carry load offset from the tie rod  292 , thereby distributing the load over a larger area. The load is distributed over two expansion devices, thereby allowing each of the expansion devices  290  to be of smaller sizes that will fit in the limited space inside a wall than if a single expansion device were used. 
         [0110]    Referring to  FIG. 44 , a slack absorber assembly  322  with an expansion devices  324  and  326 , both of which are identical. The expansion device  324  has started to expand due to a slack in the tie rod  328  while the expansion device  326  has remained inactive because the clip  310 , due to an omission by the installer, has not been removed. In this situation, the expansion devices  324  and  326  are configured so that both devices advantageously continue to squarely bear on the top rigid member  330 . The expansion devices  324  and  326  are similar to the expansion device  40  shown in  FIG. 4  but with modifications. 
         [0111]    Referring to  FIGS. 45 and 46 , each of the expansion devices includes an inner cylindrical member  332  disposed within the outer cylindrical member  68 . A resilient member or split ring  333  is received in one of the circumferential grooves  335  in the inner cylindrical member  332  and corresponding circumferential inside grooves  337  in the outer cylindrical member  62 . The spring  56  is retained around the outer cylindrical member  68  between the shoulder  68  and the retainer ring  64 , which is attached to the inner cylindrical member  332 , as already discussed in reference to  FIG. 4 . The top edge surface  334  of the inner cylindrical member  332  is convex, preferably spherical, that mates with a corresponding bottom concave surface  336  of a washer  338 . The washer  338  in combination with the surface  334  allows the washer  338  to swivel, thereby making maximum surface contact with the top rigid member  330 , even when the top rigid member  330  is not level. 
         [0112]    Threaded rods  340  are threaded to threaded openings  342  in the bottom rigid member  344 . The threaded rods  340  are slidably received within the inner cylindrical members  332  to guide the inner cylindrical members  332  in their upward movement as slack develops in the tie rod  328 . 
         [0113]    A washer  348  includes an upper concave surface  350 , preferably spherical. Another washer  352  with a convex surface  354 , preferably spherical, mates with the washer  348  to allow the washer  352  to swivel with respect to the washer  348  when the top rigid member  330  is not level. This allows the nut  356  to make maximum surface contact with the washer  352  even when the top rigid member  330  is not level. The opening of the washer  352  may be threaded to mate with the thread of the tie rod  328  to advantageously eliminate the use of the nut  356 , thereby reducing the number of components to save cost and simplify inventory. The washer  356  may be provided with hexagonal flat surfaces in the manner of a standard nut for use with a wrench or other standard tightening tool. The uneven expansion of the expansion devices may also be due to some factors, such as manufacturing tolerances, etc. The rounded edge  334  and the mating washer  338  advantageously allow for maximum surface contact with the top rigid member  364  even when the expansion devices do not expand at the same rate. 
         [0114]    It should be understood that the washers  350  and  352  are interchangeable with the two washer system shown in  FIGS. 6 and 30-32  and the modifications to the top rigid member shown in  FIGS. 33-35 . 
         [0115]    Referring to  FIG. 47 , a slack absorber assembly  358  is shown after having expanded to take up a slack in the tie rod  360 . The slack absorber assembly  358  includes the expansion device  324  and the washers  352  and  348  shown in  FIGS. 44-46 . The threaded rod  340 , which is threaded to the threaded hole  342  in a bottom plate  362 , slidably guides the inner cylindrical member  332  in its upward motion as driven by the spring  56  when a slack develops in the tie rod  360 . The washer  338  swivels with respect to the convex surface  334  to maintain maximum surface contact with the top rigid member  364 . 
         [0116]    A support member  366  disposed on the other side of the tie rod  360  provides support to the top rigid member  364  as the expansion device  324  expands to take up the slack that develops in the tie rod  360 . The support member  366  includes a rounded upper edge surface  368  that mates with a corresponding rounded groove  370  in the underside of the top rigid member  364 . As one side of the top rigid member  364  above the expansion device  324  moves upwardly, the opposite side supported by the support member  366  pivots about the surfaces  368  and  370 . The bottom edge portion  372  is held in a groove  374  in the bottom rigid member  362 . 
         [0117]    In the arrangement of the slack absorber assembly  358 , the expansion device  324  carries substantially half the load, the other half being carried by the support member  366 . The washers  348  and  352  advantageously provides maximum surface contact between the nut  356  and the washer  352  and between the washer  348  and the top rigid member  364 . The washer  338  swivels with respect to the convex surface  334  to maintain maximum surface contact with the top rigid member  364 . 
         [0118]    Referring to  FIGS. 49 and 50 , a slack absorber assembly  376  is disclosed. The slack absorber assembly  376  uses the expansion device  40  shown in  FIG. 4  on either side of the tie rod  378 . The expansion device  290  shown in  FIG. 41  is disposed such that the tie rod  378  extends through it. The inner cylindrical member  296  ( FIG. 43 ) is slidably and axially movable relative to length of the tie rod  378  as the expansion device  290  expands to take up the slack in the tie rod  378 . The washers  48  and  50  shown in  FIG. 6  are also used. In this configuration, the looseness in the expansion devices  40  while in between locking positions (when the resilient member  82  is between two receiving volumes  80 , referring to  FIG. 4 , during the process of expanding) is advantageously taken up by the expansion device  290 , which is always engaged, thereby reducing the inherent looseness in the system. 
         [0119]    Referring to  FIG. 51 , a slack absorber assembly  380  is disclosed. The slack absorber assembly  380  includes expansion device  126 , also shown in  FIG. 8 . The expansion devices  126  are disposed between the bottom rigid member  382  and the top rigid member  385  and on either side of the tie rod  384 . Threaded rods  386  are attached to the bottom rigid member  382  and are slidably movable through the top rigid member  385  as the expansion devices  126  expand to push the top rigid member  385  upwardly to take up any slack that develops in the tie rod  384 . Swivel washers  48  and  50 , also shown in  FIG. 6 , provide maximum surface contact with the top rigid member  385  and the nut  52  to account for uneven expansion of the expansion devices  126 . 
         [0120]    A split nut assembly  388  is disposed around the tie rod  384 . The split nut assembly  388  has a housing  390 , which is operatively attached to the bottom rigid member  382  with standard means, such as with bolts  392 . A cylindrical nut  394  split axially into equal segments  395 , preferably four, is disposed within the housing  390  and threadedly engaged with the tie rod  384 . A split ring  396  disposed within a circumferential groove  398  biases the cylindrical nut  394  toward the tie rod  384 . The bottom portion of the cylindrical nut  394  includes a bevel or ramp  400  that cooperates with a corresponding circumferential ramp  402  around the bottom portion of the housing  390 . A cover  404  is removably attached to the housing  390  with screws  406 . A gap  408  is provided between inner vertical surface  410  of the wall  412  and the outer vertical surface  414  of the cylindrical nut  394 . A gap  415  is provided between the bottom of the cover  404  and the top of the split nut  394 . The gap  408  allows the segments of the cylindrical nut  394  to separate away from the tie rod  384  and disengage when the cylindrical nut  394  hits and presses against the cover  404  after traversing the gap  415  as the tie rod  384  is pulled upwardly by the expansion devices  126  when a slack develops in the tie rod  384 . In the same manner, when the wall shrinks and settles, the bottom rigid member  382  moves with the wall, causing the cylindrical nut  394  to press against the cover  404  and thereby separating from the tie rod  384 . 
         [0121]    The overall diameter of the expansion device  126  is advantageously independent of the diameter of the tie rod  384 , since the expansion device  126  does not surround the tie rod  384  (i.e., the tie rod  384  does not pass through the expansion device  126 ). For example, referring to  FIG. 4 , the diameter of the axial opening  61  of the inner cylindrical member  60  can be smaller than the diameter of the tie rod  24 , or the axial opening  61  does not have to be provided so that the inner cylindrical member  60  can be made solid. The outside diameter of the inner cylindrical member  60  or the diameter of the axial opening of the outer cylindrical member  62  can even be smaller than the diameter of the tie rod  24 . Further, the size of the rods  386  are also irrelevant of the size of the tie rod  384 . 
         [0122]    Referring to  FIG. 54 , a slack absorber assembly  418  is disclosed. The slack absorber assembly  418  includes split nut assemblies  420 ,  422  and  424  disposed between a bottom rigid member  426  and a top rigid member  428 . The split nut assemblies  422  and  424  provide support between the bottom rigid member  426  and the top rigid member  428 . The split nut assemblies  420 - 424  are structurally and functionally the same as the split nut assembly  388  shown in  FIGS. 52 and 53 , including respective cylindrical nuts  394 . The split nut assembly  420  is attached to the bottom rigid member  426  with bolts  429  or other standard means. The bottom rigid member  426  is attached with screws  431  or other standard means to the wall structure  427 , such as the stud wall base plate. The split nut assemblies  422  and  424  are attached to the  428  with bolts or other standard means. The split nut assemblies  422  and  424  are oriented inverted with respect to the split nut assembly  420 . The split nut assemblies  422  and  424  are attached to the top rigid member  428  with bolts  433  or other standard means. Threaded rods  430  and the tie rod  432  cooperate with the respective cylindrical nuts  394  in the same way as already described with the split nut assembly  388  shown in  FIGS. 52 and 53 . The threaded rods  430  are attached to the bottom rigid member  426 , such as by threading into respective threaded holes in the manner shown in  FIG. 9 . The threaded rods  430  are slidably movable through the top rigid member  428  through respective openings in the manner shown in  FIG. 9 . A nut  434  attaches the top rigid member  428  to the tie rod  432  such that the top rigid member  428  remains stationary with respect to the tie rod  432 . 
         [0123]    The tie rod  432  due to its relatively larger diameter (larger than what is required for the load) acts as a post such that when the wall shrinks or settles, the slack absorber assembly  418  moves with the wall, since the bottom plate  426  is attached to the wall structure  427 . The threaded rods  430  moves with the bottom plate  426 , causing the respective cylindrical nuts  394  in the split nut assemblies  422  and  424  to press against the respective covers  404  and disengage from the respective threaded rods  430 . When movement ceases, the respective split rings  396  bias the segments  395  to engage the respective threaded rods  430  and the tie rod  432 . When uplift occurs due to wind or other forces, the respective cylindrical nuts  394  will engage the respective threaded rods  430  and the tie rod  432  from the cooperating actions of the respective ramp surfaces  400  of the respective cylindrical nuts pressing against the corresponding respective ramp surfaces  402  of the respective housings. 
         [0124]    Referring to  FIG. 55 , devices A, B, C, D and E are disclosed in various configurations between the bottom rigid member  436  and the top rigid member  438 . Devices A and B are the same type as the expansion device  126  disclosed in  FIG. 9 . Device C is the same type as the expansion device  290  without the bolt  318  as shown in  FIG. 43 . Devices D and E are split nut assemblies  388  of the type shown in  52  and  53 . 
         [0125]    Where there are three devices shown in a row, the middle device is disposed in the center with the tie rod  440  extending through the middle device. The tie rod  440  is able to move relative to the middle device. The threaded rods  442  are attached to the bottom rigid member  436  and provide a guide for the upward movement of the left and right devices. 
         [0126]    In the following discussion, the various configurations are labeled as B-B, A-B, A-C-A, A-B-A, B-E-B and D-E-D. 
         [0127]    In the B-B configuration, the left device B is offset from the right device B so that they do not lock at the same time. This effectively shortens the locking distance  446 , which is the distance between the receiving volumes  80 , and therefore, reduces the looseness in the system. When one of the devices is locked, as shown for the right device, the resilient member  82  of the other device will be between two adjacent receiving volumes, as shown for the left device. This effectively shortens the locking distance by about a half. The distance  446  for the device B on the left is equal to the distance  446  on the device B on the right. The illustrated distance  446  is 0.0750 in. For the arrangement shown, there is locking every 0.0375 in. without shortening the distance  446  between the receiving volumes  80 . Shortening the distance  446  is not preferable to avoid shearing of the receiving volumes  80  during load conditions. The configuration advantageously makes system tighter to effectively withstand the load it is designed for. 
         [0128]    In the A-B configuration, the distance  448  in the device A between adjacent volumes  80  is longer than the distance  450  for the device B. In the illustrated example, the locking distance  448  of the device A is 0.2000 in. versus the locking distance  450  of 0.0750 in. of the device B. This means that the device B will lock about two times before the device A locks. This ensures that there will be more chances that one of the devices will be locked at any time to hold the tie rod  384  tight to the foundation against any uplift forces, thereby decreasing the looseness in the system without decreasing the strength of the components. The configuration advantageously makes system tighter to effectively withstand the load it is designed for. 
         [0129]    In the A-C-A configuration, the center device C is always engaged to take up the entire load when the devices A are between locking positions. The distances  452  are equal to each other, for example 0.2000 in. The looseness of the relatively long distance  452  is advantageously absorbed by the threads of the center device C. The configuration advantageously makes system tighter to effectively withstand the load it is designed for. 
         [0130]    In the A-B-A configuration, the locking distance  454  for the center device B is shorter than the locking distance  456  for the devices A. The configuration ensures that the center device B is locked more times than the outlying devices A. As an example, the distance  454  is 0.0750 in. while the distance  456  is 0.2000 in. This configuration advantageously reduces the looseness of the outlying devices A by having the center device with shorter locking distance  454 . The configuration advantageously makes system tighter to effectively withstand the load it is designed for. 
         [0131]    In the B-E-B configuration, the device E is attached to the bottom rigid member  436 . The tie rod  384  is relatively larger in diameter (larger than what is required for the load) so that it acts as a post. When the wall shrinks and settles downwardly, the split nut opens up and moves downwardly to engage the lower thread portion. The outlying devices B will expand to take up the slack between the nut  444  and the top rigid member  438 . The locking distance  458  for the devices B is illustrated at 0.0750 in. while the thread pitch  460  for the screw threads is longer, illustrated at 0.1429 in. This will insure that the devices B are locked when the split nut is still open, thereby taking up the looseness in the system. The configuration advantageously makes system tighter to effectively withstand the load it is designed for. 
         [0132]    In the D-E-D configuration, as already described in connection with  FIG. 54 , the shorter thread pitch  462  for the devices D as compared to the thread pitch  464  of device E allows for tightness of the assembly in case the threads of the device E do not engage completely due to a movement of less than the thread pitch of the device E. The thread pitch  462  is illustrated as 0.0769 in. while the thread pitch  464  is 0.1429 in. 
         [0133]    With the use of combination of expansion devices with different locking distances, looseness in the system is advantageously reduced to make the system tighter to effectively withstand the load it is designed for. 
         [0134]    It should be understood that other combinations are also possible, such as D-D, E-E, E-B and C-C. Further, any one of the devices A, B, C, D and E may be used in the configuration shown in  FIG. 47 , in lieu of the expansion device  324 . 
         [0135]    Referring to  FIG. 56 , the standard nut  52  is replaced with a split nut assembly  466 . The split nut assembly  466  is similar to the split nut assembly  388  shown in  FIGS. 52 and 53 . A nut  468  split axially into four segments  470  are disposed inside a housing  472 . A cover  474  is screwed to the housing  472 . The cover  474  includes an inside conical surface  476  that cooperates with a circumferential flange  478  at the upper portion of the nut  468 . A circumferential groove  480  is provided between the conical surface  476  and an inside conical surface  482  at the inside upper portion of the housing  472 . The inside bottom portion of the housing  472  includes a conical surface  484  that cooperates with corresponding conical surface  486  at the bottom portion of the nut  468 . Resilient split rings  488  disposed in respective circumferential grooves  489  hold the segments  470  of the nut  468  together. Space  490  between the nut  468  and the inside surface of the housing  472  allows the nut  468  to expand and disengage from the thread of the tie rod  486 . 
         [0136]    In operation, when the split nut  468  is slid down the tie rod  492  until it engages the washer  50 . With the application of a downward force, the conical surface  476  causes the circumferential flange  478  to rise into the groove  480 , thereby forcing the opening of the nut  468 . When a downward force is exerted on the tie rod  492 , the nut  468  tightens around the tie rod  492  from the action of the bottom conical surface  486  against the housing conical surface  484 . 
         [0137]    It should be understood that the split nut assembly  468  may be used in any of the slack absorber assemblies disclosed herein in lieu of the nuts  52 ,  356  and  444 . 
         [0138]    Referring to  FIG. 58 , a slack absorber assembly  493  is provided with a top rigid member  494  with a threaded opening  496  that mates with the thread on the tie rod  492 . The threaded top rigid member  494  advantageously eliminates the use of the standard nut  52 . The slack absorber assembly  493  is similar to the slack absorber assembly  231  shown in  FIG. 28 , except that the washers  48  and  50  and the nut  52  (shown in  FIG. 3 , for example) is not used. The tie rod  492  due to its relatively larger diameter (larger than what is required for the load) acts as a post such that when the wall shrinks or settles, the expansion devices  40  and  44  expands downwardly to take up any gap that develops between the bottom rigid member  38  and the horizontal wall structure, such as the wall bottom plate  16  or  100 , on which the bottom rigid member  38  rests. The opening  232  is oversized to avoid interference with the tie rod  492  during the downward expansion of the slack absorber assembly  493 . 
         [0139]    Referring to  FIG. 59 , the slack absorber assembly  112  shown in  FIG. 9  is modified as slack absorber assembly  498  with elongated threaded rods  500  and an extended bottom rigid member  502  that extends below the bottom ends of the studs  106 . The placement of the bottom rigid member  502  advantageously provides additional bearing surface on the wall bottom plate  100  and additional load bearing connections with the wall. In addition to the load imposed by the expansion devices  40  and  44 , the studs  106  provide additional load transfer to the wall. 
         [0140]    The nuts  138  after installation of the slack absorber assembly  498  are unscrewed a distance from the top rigid member  46 . This allows the expansion devices  40  and  44  to expand only to the limit of the positions of the nuts  138 , as the top rigid member  46  moves upwardly along the threaded rods  500 . The nuts  500  disposed a distance from the top rigid member  46  advantageously act as stops for the top rigid member  46  and the expansion devices  40  and  44  such that the inner cylindrical member  60  will not overshoot the outer cylindrical member  62  during expansion, thereby insuring that the inner cylindrical member  60  remains locked to the outer cylindrical member  62  when a downward force is exerted by the top rigid member  46  when the wall is subjected to lift or shear forces during a storm, earthquake, etc. 
         [0141]    It should be understood that the various expansion devices described herein are interchangeable with one another in any of the various slack absorber assemblies disclosed herein. For example, the expansion device  290  may be substituted for the expansion devices variously labeled as  40 ,  42 ,  44 ,  126 ,  128 ,  324 , and  326  or the split nuts variously labeled as  388 ,  422  and  424 . 
         [0142]    While this invention has been described as having preferred design, it is understood that it is capable of further modification, uses and/or adaptations following in general the principle of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as may be applied to the essential features set forth, and fall within the scope of the invention or the limits of the appended claims.