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CROSS REFERENCE TO RELATED APPLICATION 
     This application claims benefit of U.S. Provisional Patent Application No. 61/930,401, filed Jan. 22, 2014, which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     This invention pertains to construction and more particularly to expansion of existing houses and the like. 
     Many houses constructed during the post-World War II housing boom are single story dwellings. While the ‘ranch style’ house was popular then, now, with the price of land at a premium and consumers desiring larger, more spacious houses, multi-story dwellings are becoming the standard. Multi-story houses benefit not only the inhabitants but owners as well. The additional stories increase the size and the value of the house commensurately. 
     Financially it often is impractical to buy an existing single story house, demolish it and rebuild a new multi-story dwelling; rather, it would be ideal if the existing structure could be modified to increase its size. If the land size is large enough, it would be a simple matter to just build the house out farther but, many times, the house is already at a maximum size allowed per regulated footprint and setbacks for the land on which it resides. 
     Therefore, the only way to keep the existing structure and increase the size of the dwelling is to add additional levels. Converting a single story structure to a two-story effectively doubles the size of the living space and markedly increases the value of the structure. Traditionally, the addition of levels to an existing structure is an expensive and time consuming process that often yields minimum returns on investment. A new system and method for adding levels to an existing structure at a minimal cost and time would be most beneficial. 
     Currently, the process of adding an additional level to an existing structure requires the complete removal and destruction of the roof. The roof must be removed to allow the new level to be constructed and to allow access for the reinforcement of the existing structure. Reinforcement of the existing structure must often be done since the initial construction was not done in a manner to support the non-existent additional level(s). Once reinforced, the additional level(s) could be constructed on top of the existing structure. Finally, a new roof structure can be formed to complete the remodeling process. The removal and reconstruction of the roof structure adds additional time and cost to the process of adding the new level(s). 
     The invention enables a method for raising a structure with a jacking system for installation of a building element, which comprises one or more of vertical jack assemblies and a system to control the rate at which the structure can be elevated by the jack assemblies independently of each other jack assembly. 
     An object of this invention is to reduce the time and cost associated with the addition of new level(s) to an existing structure. The invention preserves the existing roof structure, creates a new system to rapidly construct the new level on the existing structure and utilizes pre-manufactured components to further decrease the cost and improve efficiency. 
     SUMMARY OF THE INVENTION 
     The invention is a system and method capable of lifting an entire structure, the roof of a structure or some portion of a structure. The invention uses a system of frames about the periphery of the structure to which jack members are mounted. The jack members extend to raise the desired structure or portion thereof. A control system is also provided to manage the lifting process; the control system monitors the lifting process and controls the rate of the extension of the jack members. 
     The lifting system and method disclosed has many advantages over the previous systems and methods. The invention does not require the use of specialized lifting beams to lift the structure or parts thereof. Additionally, since the installation of the system is within the footprint of the structure, there is minimal clearance required about the structure to be lifted. 
     When used on a roof structure, the system and method preserves the existing roof by lifting the roof vertically to install an additional story in the structure below. The vertical lifting also minimizes the potential for damage to the roof structure during the construction process since the roof is not moved laterally which can shift or damage the roof structure. Typically when a roof is removed to install an additional level in the structure, the roof requires reinforcement before the lifting process can begin, with the invention, the roof does not require such strengthening. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIGS. 1-8  are conceptual drawings showing in perspective view the steps of enlarging a building structure such as a single-story house by raising the roof structure, adding floor structure and installing walls for a second story under the raised roof, using a jacking system according to an embodiment of the invention. 
         FIG. 9  is a side elevation view of the wall jacking installation as initially installed on a side of a building structure and coupled to the roof structure. 
         FIG. 10  is a side elevation view of the wall jacking system of  FIG. 9  following an initial lift of the roof structure and placement of lateral bracing. 
         FIG. 11  is a side elevation view of the wall jacking system of  FIG. 10  following a final lift of the roof structure, extension of the lateral bracing and installation of new second story floor framing. 
         FIG. 12A  is a cross-sectional view through the building wall of  FIG. 9  showing details of connection of the jacking system to the sill plate and the roof structure. 
         FIG. 12B  is an enlarged view of the connection of  FIG. 12A  to the roof structure. 
         FIG. 13  is a cross-sectional view through the building wall of  FIG. 10  showing details of connection of the upper portion of the jacking system and lateral bracing to the upper portion of the existing wall and to the roof structure. 
         FIG. 14  is a top plan view of the drive element  1400  used on the bottom rail for driving one of the wall jacks in  FIGS. 9-13 . 
         FIG. 15  is a side elevation view of the drive element  1400  of  FIG. 14 . 
         FIG. 16  is a cross-sectional view of the drive element  1400  of  FIG. 15 . 
         FIGS. 17A-17C  are side views of non-metallic slider blocks in the vertical lifting elements  230 . 
         FIGS. 18A-18D  are cross sectional views of non-metallic slider blocks in the vertical lifting elements  230  of  FIGS. 17A-17C . 
         FIG. 19A  is a perspective view of the non-metallic lifting block  241 .  FIG. 19B  is a side elevation view of the lifting block  241 .  FIG. 19C  is a top plan view of the lifting block  241 . 
         FIG. 20A  is a side view of the diagonal cross-brace outer tube and ‘lock pin block’ of  FIGS. 11 and 13 . 
         FIG. 20B  is a top view of the diagonal cross-brace outer tube and ‘lock pin block’ of  FIGS. 11 and 13 . 
         FIGS. 21 and 22  are conceptual drawings showing in perspective view the steps of raising an entire building with a jacking system for repair or replacement of sill plates, supporting walls, and or footings, using a jacking system according to an embodiment of the invention. 
         FIG. 23  is an enlarged side elevation view of the drive element  1400  located between the floor joists for lifting an entire building. 
         FIG. 24  is a cross-sectional view of the drive element  1400  of  FIG. 23 . 
         FIG. 25A  is a side elevation view of the jacking system showing upper and bottom horizontal rails in preparation of securing diagonal bracing and lifting an entire building;  FIG. 25B  is a plan view of the bottom rail; and  FIG. 25C  is an enlarged view of  FIG. 25B  showing the interconnection to the vertical lifting element. 
         FIG. 26  is a side elevation view of the jacking system showing diagonal bracing secured to upper and bottom horizontal rails in preparation of and lifting an entire building. 
         FIG. 27  is a side elevation view showing placement of diagonal bracing to provide lateral stability of lifted structure while at same time providing sufficient space to excavate, prep and pour new footings and foundation walls. 
         FIG. 28  is a cross sectional view showing general location of threaded rod support blocks for the jacking system when raising either a roof structure or raising an entire building. 
         FIG. 29  is side elevation view showing general location of threaded rod support blocks for the jacking system when raising either a roof structure or a complete structure as shown in  FIG. 25A . 
         FIGS. 30A-30D  are cross sectional views of a vertical lifting jack assembly showing the threaded rod support blocks at various sections in  FIG. 29 . 
         FIGS. 31A-31B  show transverse sectional views of the tubing section in its normal location to keep the threaded rod support blocks in place. 
         FIGS. 32A-32B  show transverse sectional views of the tubing section in its raised position to either install or replace the threaded rod support blocks. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a single story structure  100  to which an additional level(s) will be added. The roof  102  sits atop the main section  104  which is supported by the foundation sill plate  106 . 
       FIG. 2  shows the structure of  FIG. 1  with the lifting rails  200 ,  210 , and  220  installed around the periphery of the structure  100 . The bottom lifting rail  200  is fastened to the sill plate  106  of the structure  100  and will serve as the base of the lifting system. The middle lifting rail  210  is attached about the upper periphery of the structure  100  and below the roof structure  102 . Middle rail  210  is attached through the sides of the house and into the vertical studs of the main section  104 . The upper lifting rail  220  is installed about the lower periphery of the roof  102  of the structure  100 . The rail  220  is attached to the sill of the roof and/or attached to the ends of the rafters of the roof  102 . 
       FIG. 3  shows the rails  200 ,  210  and  220  installed on the structure  100  and roof  102 . The rails are interconnected by vertical lifting elements  230 . The vertical lifting elements  230  will exert an upward force on upper rail  220  that will cause the roof structure  102  to lift up and away from the structure  100 . In addition to the vertical lifting elements  230 , extendible cross-braces  240  are installed between rails  210  and  220 . The bottoms of cross-braces  240  are anchored to brackets affixed to the middle rail  210 , the extendible end of the cross-braces  240  are attached to the rail  220  by a bracket, the upper and lower connection points allowing the end of the cross-brace to rotate about the connection points in the vertical plane of the structure. 
       FIG. 4  illustrates the initial phase of the lifting process. The roof  102  is attached to the upper rail  220  that has been raised via the vertical lifting elements  230  to a first position an initial distance above the structure  100 . As the roof structure  102  is raised, the ends of the cross-braces  240  extend and the ends rotate about their respective pin joints thereby providing lateral stability to the roof structure that has been separated from the perimeter walls of the house. The cross-braces  240  are allowed to automatically extend as the structure  102  is raised, but are prevented from retracting by an internal retaining element. The internal retaining element is a feature that allows the cross-braces to act as compression only members that will provide lateral stability of the existing roof and wall structure during lateral loads from construction, wind or seismic loads. The cross-braces are retractable by a user actuating a release mechanism that releases the internal retaining element thus allowing the cross-braces to retract automatically or by the user. 
       FIG. 5  shows the installation of the additional floor  502  atop the main section  104 , which formerly supported the roof  102 . The roof  102  is still at the initial position as lifted to in  FIG. 4 . This initial position is at a minimum height necessary to allow the installation of the floor  502 . 
       FIG. 6  illustrates the second phase of the lifting process. The roof  102 , attached to rail  220 , has been lifted higher than the final height of the new walls. Extendible cross-braces  240  have extended further to continue to provide lateral stability of the roof structure  102  and the existing walls  104 . 
       FIG. 7  shows the installation of the new walls  504 , framing the periphery of the new level atop floor  502 . Once the walls  504  are completed, the roof structure  102  is lowered down upon the new walls and reattached atop the new walls  504  to complete the two-story structure. 
       FIG. 8  shows the completed two-story structure with the lifting system and equipment removed from the building. The structure now has an additional story added to the pre-existing structure at minimal cost and time spent. 
       FIG. 9  is a schematic showing details of the lifting system attached to the structure  100 . The bottom lifting rail  200  is attached to the sill plate  106 . The bottom lifting rail  200  has holes  202  spaced regularly along the length of the rail  200 . Multiple bottom rail elements  200  are interconnected to encircle the perimeter of the sill plate  106 . The rail elements  200  are connected to one another using a butt joint  910 . The rails  200  have holes  202 A at each end. The butt joint  910  is inserted inside the end of a rail  200  and is locked in place by inserting retaining pins in the end holes  202 A and through the holes on the butt joint. The end holes  202 A are spaced to ensure that the spacing of the holes  202  is maintained across the interconnection at the butt joint  910 . The interlocked elements of the lower rail  200  form a rigid framework that encircles the sill plate  106  and will act as the lower structure of the lifting system. 
     The top lifting rail  220  is attached to the roof structure  102 . The top rail  220  is attached to the structure  102  via the ends of the roof rafters. Rail  220  encircles the roof structure  102  and will support the structure during the lifting process. The roof normally provides structural integrity to the structure  100 . It acts as a diaphragm and holds the wall together and, in turn, the walls provide the rigid base on which the roof  102  sits. If separated from the structure  100 , the roof structure  102  has a tendency to splay out and deform from the original shape, when this occurs, the roof is typically beyond salvage and must be rebuilt. Using this method and system, the rail  220  will maintain the form and size of the roof structure  102  when it is separated from the structure  100 . This will ensure that the roof  102  can be reattached to the new walls once they are installed atop the main section of the existing structure. The reuse of the existing roof structure  102  is more cost and time efficient than the previously existing method in which the majority of the structure would have to be rebuilt or time consumingly reshaped to fit. 
     The middle lifting rail  210  is attached around the upper periphery of the main portion  104  of the structure  100 . The middle rail  210  is attached to the studs of the house. Depending on the strength of the existing structure, the middle rail  210  can be attached to every stud or at some other regular or irregular interval. As with the bottom rail  200 , middle rail  210  is made of individual elements that are interconnected using butt joints  910 . Rails  210  also have the same hole pattern as that of rail  200  and  220 , in this manner, the rail combination has spaced set of vertically arrayed hole patterns. Similar to the top rail  220 , the middle rail  210  will maintain the dimensions of the main section  104  during the lifting process. With the roof removed, the walls are not braced for out of plane loads and would have a tendency to warp and move out of position, if not properly restrained in their position. This would necessitate a laborious process of “truing” or straightening the walls back to their original positions before the roof could be attached. The retention of the original dimensions and shape of the main section  104  during the lifting process allows the quick installation of a second story floor and additional walls atop and then the reattachment of the roof with minimal time and cost. 
     The vertical lifting elements  230  are attached at regular or irregular intervals around each side of the house and interconnect the rails  200 ,  210  and  220 . Elements  230  are affixed to each rail using the holes  202  disposed on each rail. The system of holes on each rail allows for the quick attachment and removal of the lifting elements  230 , additionally, the vertically-aligned pattern of holes makes it easy for someone installing the lifting elements  230  to space them properly and position them vertically around the periphery. 
       FIG. 10  shows the roof lifted to the initial position. The extendible, diagonal cross-braces  240  have been installed. The upper ends of the diagonal cross-braces may be attached at a common root point  1002  or at separate locations on the top lifting rail  220 . The common root point  1002  may be a single bracket or separate brackets attached to the top rail  220 , the cross brace ends are attached to the bracket(s) by pin joints  1004 . The lower ends of the cross-braces  240  are affixed to the middle lifting rail  210  at points  1006  spaced equidistant from the root point  1002 . The connection points  1006  are brackets similar to or the same as bracket  1002 , and attach the lower end of the cross-brace  240  to the middle rail  210 . The lower end of the cross-brace  240  attaches to the bracket  1006  at a pin joint  1008 . The use of the pin joints allows the cross braces to rotate about the joint as the angle between the cross-brace  240  and middle rail  210  changes due to the lifting of the roof  102 . As the roof is lifted, the cross-braces  240  will automatically extend and lock in position. In this manner, they provide lateral stability to the roof structure  102 . The cross-braces  240  can utilize a ratcheting mechanism that allows them to be extended but will not allow them to be shortened until an external operation releases the ratchet mechanism and allows the extension pieces of the cross-braces to retract back into the main body tube of the cross-braces  240 . The locking extension action can also be achieved by shaped frictional rings that allow for free extension but are locked into position upon application of back pressure. There exists many ways to achieve the locking extension mechanism and are well known to those skilled in the art. Each face of the structure would have at least one set of the cross braces installed. 
     As can be seen in  FIG. 11 , the vertical lifting elements  230  are telescoping. The main body  232  of the lifting element  230  is affixed at its top end to the middle lifting bar  210 , while the bottom end is affixed to the lower lifting bar  200 . The extension portion  234  is moveable within the main body  232  and connects to the top rail  220  and exerts the upward lifting force and motion to raise the roof structure  102  above the main structure  104 . The extension portion  234  may be a single telescoping piece that moves within the main body  232 , or may contain multiple telescoping pieces that nest within each other. Also seen in  FIG. 11  are the extension elements  242  of the cross-braces  240 . These are one-way extendible, meaning the extension elements will extend from the cross-braces  240  as the roof structure  102  is raised by the lifting elements  230 , but will not automatically retract back within the cross-brace  240  unless an external manipulation is performed to release them. This provides lateral stability to the roof structure  102  and the existing walls  104 . 
       FIG. 12A  is a detailed schematic view of the vertical lifting element  230  attached to the top, middle and bottom lifting rails  220 ,  210  and  200 . The bottom lifting rail is attached to the sill plate via brackets  204  that are mounted to the sill plate  106  via mechanical fasteners. Before adding the additional level(s) to the structure, a study must be carried out to determine if the existing foundation and sill plate  106  is adequate to support the additional load. If the foundation and sill plate is found to not be adequate, it must be retrofitted or reinforced before the lifting system can be installed and used. The bracket used to mount the lower lifting rail to the sill plate can be integrated into the bracket that holds the vertical lifting element to the lower lifting bar  200  or it may be a separate piece. It is advantageous to use an integrated bracket that performs both functions as the added strength due to mounting of the bracket to the sill plate will help support the loads exerted on the vertical lifting element  230  as the roof load is elevated. The top of the lifting element main tube is attached to the middle rail  210 . The middle rail  210  is attached to the studs of the structure  100  by a bracket  214  affixed by mechanical fasteners like the foundation bracket. Like the foundation bracket  204 , the middle rail bracket  214  can be similar, attaching both the rail to the stud and the vertical lifting element to the rail. The top of the extension portion  234  of the vertical lifting element  230  is attached to the existing rafters or trusses with a bracket  222  attached to the top rail  220  and the perimeter roof structure  102  as better shown in  FIG. 12B . At gable ends, the top rail  220  attaches to the end rafter or truss top chord just below the roof sheathing similar to the method that the mid rail  210  is attached to the exiting walls  104 . 
       FIG. 13  is a detailed schematic view of a wall cross-section showing the detail of the diagonal cross-brace element  240 . The bottom end of the element  240  is attached to the middle rail by a bracket  244 . Extending from the bracket is a reinforced strap  248  that is further screwed to a wall stud of the building to provide a more secure and unmoving mounting point for the cross-brace  240 . The upper end of the cross-brace  240  is attached to the top rail via a bracket  246 . 
       FIG. 14  is a top view detailing the mounting of the vertical lifting element drive motor. The drive element  1400  is attached to the lower mounting rail and lower mounting rail bracket. A transformer supplying power to the drive element can be mounted on the lower rail at a nearby position using a set of the pre-drilled holes  202 . 
       FIG. 15  shows a detailed side view of the drive element  1400  and bracket  107 A and  FIG. 16  shows a detailed top view of the drive element  1400  showing lifting rod  1406  in cross-section. The drive element  1400  has a drive motor  1402  that is attached to the drive gear box  1404  that drives a self-locking Acme threaded lifting rod  1406 . Each vertical lifting element  230  has a drive block attached to the threaded lifting rod  1406  that elevates the extending portion  234  as the threaded lifting rod  1406  is rotated. The extending portion  234  is driven a pre-determined height and then pinned at that height via a cotter pin that slides through the main tube and extending portion. For lifting elements that have multiple extending portions, each telescoping portion is pinned through the surrounding tubes to hold them in their extended positions. The internal lifting element is driven upwards by a drive block which engages the thread of the threaded lifting rod  1406 . Once the internal drive block has reached the top of the threaded lifting rod  1406 , the extending portions of the vertical lifting elements  230  are pinned at that height and the internal drive block is lowered as the threaded lifting rod  1406  is reversed and lowers back to the bottom of the lifting element  230 . There a different and second drive block reengages the threaded lifting rod  1406  and is again driven upward, repeating the lifting process. By having equal lengths of internal lifting element(s) in each vertical lifting element  230 , ensures that all the vertical lifting elements  230  extend to an equal height with each lifting process. Thus the roof structure  102  does not get warped or broken and the weight stays evenly distributed across each of the vertical lifting elements. Each drive element  1400  is attached to a central driving control panel that ensures each drive element  1400  is driven the amount required to maintain the roof structure level and a controlled lift. There exist other lifting options available that can be used in this system, such as hydraulic pistons or jacks. 
       FIGS. 17A-17C  is an exploded side view of non-metallic slider blocks  241  in the vertical lifting element  230 . The vertical lifting element  230  is composed of an inner element  230 A, a middle element  230 B and a main element  230 C. The non-metallic slider blocks  241  are secured in place by a projection that engages holes in the members of the telescoping vertical lifting element  230 . The engagement holes on the various elements  230 A,  230 B and  230 C are of two differing sizes to accommodate two differently sized non-metallic slider blocks  241 A and  241 B. The nonmetallic slider block  241 A has a sliding surface diameter nearly the width of a face of the inner element  230 A. The same slider block  241 A is also disposed at an end of the element  230 B that inner element  230 A extends outwards from an opposite end of the element  230 B, slider block  241 B is disposed, having a diameter nearly the width of the face of the middle element  230 B. Main element  230 C has a slider block  241 B disposed at an end. The non-metallic slider blocks align the elements  230 A,  230 B and  230 C of the lifting element  230 , which prevents the various elements from rubbing or twisting inside of each other during the lifting process. The outer shape of the non-metallic slider blocks  241  can be round, square, rectangular or a profile not here described. The shape of the projection on the non-metallic slider blocks  241  can be round, square, rectangular or a profile not here described. The non-metallic slider blocks are ideally made of a high molecular weight plastic having a low friction coefficient, but sufficient material strength to resist compression. 
       FIGS. 18A-18D  is a cross sectional view of the non-metallic slider blocks  241  in the nested vertical lifting elements  230 . The projections on the non-metallic slider blocks  241  are shown engaging holes in the members of the vertical lifting elements  230 . 
       FIG. 19A  is a perspective view of a circular example of the non-metallic lifting block  241 . The block has a large diameter  243  and a small diameter  245 . The flat face of the large diameter  243  is the friction face that contacts a portion of the lifting element  230  as it slides. The small diameter  245  sits in holes in the lifting elements  230  and provides restraint to hold the nonmetallic slider block  241  in place on the lifting element.  FIG. 19B  is a side elevation view of the non-metallic slider block  241 .  FIG. 19C  is a plan view of the non-metallic slider block  241 . 
       FIG. 20A  is a side view and  FIG. 20B  is a top view of the diagonal cross-brace outer tube and a separate ‘lock pin block’ item  258 . The diagonal cross-braces  240  can utilize an internal ratcheting mechanism here defined as a ‘lock pin block’ item  258 . The ‘lock pin block’ item  258  engages with the corresponding indentations of the inner tube of the diagonal cross-braces  240 , as shown in section G-G. This allows the diagonal cross-braces  240  to be extended but does not allow the diagonal cross-braces  240  to be shortened until an external operation releases the ratchet mechanism or ‘lock pin block’ item  258 . The release of the ‘lock pin block’ item  258  enables the inner tubes of the cross-brace to retract back into the outer body tube of the cross-brace  240 . The spring loaded index plunger, as shown in  FIG. 20A , is an example device that may be used to index and restrain an object, in this case, the removable ‘lock pin block’  258 . 
       FIG. 21  shows a complete structure  100  which may be lifted for repair or replacement of sill plates, supporting walls, footings and other structural features. Additionally, the building may be lifted to add an additional level(s) to the structure. In a further embodiment, the structure may be lifted and the roof structure may be, simultaneously or separately, lifted to accomplish the desired construction tasks. 
       FIG. 22  shows the structure of  FIG. 21  raised with the telescoping wall jacks  230 , with diagonal braces  240 , installed to avoid wracking. 
       FIG. 23  shows a detailed side view of the drive element  1400  and bracket  107 A.  FIG. 24  shows a detailed top view of the drive element  1400  of  FIG. 23 . The drive element  1400  has a drive motor  1402  that is attached to the drive gear box  1404  that drives a self-locking Acme threaded rod  1406 . Each vertical lifting element  230  has a drive block attached to the threaded rod  1406  that lowers the extending portion  234  as the threaded lifting rod  1406  is rotated. The extending portion  234  is driven a pre-determined length by an internal drive block and then pinned via a cotter pin that slides through the main tube and extending portion. For lifting elements that have multiple extending portions, each telescoping portion is pinned through the surrounding tubes to hold them in their extended positions. The internal lifting element is driven downwards by a drive block which engages with the threads of the threaded rod  1406 . Once the internal drive block has reached the end of the threaded lifting rod  1406 , the extending portions of the vertical lifting elements  230  are pinned. The internal drive block is returned to an initial position as the threaded rod  1406  is reversed. Once the drive block is returned, a different and second drive block is inserted and reengages the threaded rod  1406 . The new drive block is driven downward, repeating the lifting process. Having equal lengths of internal lifting element(s) in each vertical lifting element  230  ensures that all the vertical lifting elements  230  extend an equal length with each lifting process. In doing so, the building structure  100  does not get warped or damaged since the weight stays evenly distributed across each of the vertical lifting elements. There exist other lifting options available that can be used in this system, such as hydraulic pistons or jacks. 
     Each drive element  1400  is attached to a central driving control panel that ensures each drive element  1400  is driven, either independently or in unison, such that structure remains level and lift is controlled. An example control means could include monitoring of the amperage drawn by each drive element  1400 . A method of monitoring the amperage drawn by each of the drive elements  140  can be an ammeter attached to each drive element. The amperage drawn by each drive element  1400  is correlated to the amount of torque each drive element  1400  is exerting to lift the structure. Should the amount of amperage drawn by a drive element  1400  spike, it can be indicative of unequal loading which could mean that the load is now unbalanced or proceeding at unequal rates. The controller can vary the amount of power and lift rate of each of the drive elements  1400  to rebalance and relevel the structure. 
     Alternative control and measurement systems can be used, such as load cells on each drive element, voltage monitoring of the drive elements  1400  and/or the system as a whole or others, level and/or alignment sensors on the jacks and/or structure, or some combination thereof. An example alignment sensor system is a system of sensors that relay the relative position and/or extension length of a wall jack member in relation to the other wall jack members. Aligning the lifting of each of the wall jack members lifts the structure in a stable and balanced state as desired. 
       FIG. 25A  is a schematic side elevation showing details of the lifting system attached to the structure  100 . The top lifting rail  220  is attached to the structure  100  at the underside of the floor joists as also previously shown in  FIG. 23 . The bottom lifting rail  200  has holes  202  spaced regularly along the length of the rail  200 . Section A-A is identified to further define method of attachment of the bottom rail  200 . 
       FIG. 25B  is a schematic top view of the lifting system and identifies that both top lifting rail  230  and bottom rail  200  are attached to the same side of the outer element  230 C of the vertical lifting elements  230 . 
       FIG. 25C  shows cross Section A-A identifying bracket  247  has an integral locating pin  248  that engages in a hole in the outer element  230 C of the vertical lifting elements  230 . Hardware connects bracket  247  to the bottom rail  200  through holes  202 A, thereby rigidly linking the vertical lifting elements  230  together with top rail  220 . Multiple bottom rail elements  200  are interconnected to form a rigid framework that links together predetermined vertical lifting element assemblies  230  and acts as the lower structure of the lifting system. The bottom rail elements  200  are connected to one another using a butt joint  910 . The rails  200  have holes  202 A at each end. The butt joint  910  is inserted inside the end of a rail  200  and is locked in place by inserting retaining pins in the end holes  202 A and through the holes on the butt joint. The end holes  202 A are spaced to ensure that the spacing of the holes  202  is maintained across the interconnection at the butt joint  910 . 
       FIG. 26  shows a detailed method of applying extendible cross-braces  240  between ‘pairs’ of wall jacks  230  to provide lateral stability of lifted structure. The spacing of the wall jacks  230  and cross-braces  240  provides sufficient space to accomplish the desired construction steps. With the structure raised, workers can excavate, prep and pour new footings and foundation walls and or add an additional level(s) under the original level. The ‘lock pin block’ item  242  is shown on each extendible cross-braces  240 . 
       FIG. 27  shows a detailed method of applying extendible cross-braces  240  between predetermined ‘pairs’ of wall jacks  230  to provide lateral stability of lifted structure while providing access required to excavate, prep and pour new footings and foundation walls. 
     The vertical lifting elements  230  are attached at regular or irregular intervals around each side of the house, and other predetermined locations to interconnect the rails  200 , and  220 . Elements  230  are affixed to each rail using the holes  202  disposed on each rail. The system of holes on each rail allows for the quick attachment and removal of the lifting elements  230 . Additionally, the vertically-aligned pattern of holes makes it easy for someone installing the lifting elements  230  to space them properly and position them vertically around the periphery or other predetermined locations. 
       FIG. 28  shows a detailed schematic view of a wall cross-section showing the detail of the method using the tube  230 D to provide and retain replaceable threaded rod supports  249  thereby limiting deflection due to the applied vertical load when lifting either a roof structure or an entire building. 
       FIG. 29  shows a detailed schematic side view of a structure with Section B-B and Section D-D identified to show the detail of the method to provide and retain replaceable threaded rod supports  249  using the tube  230 D. 
       FIG. 30A  shows a detailed cross Section C-C of outer element  230 C of lifting element  230  showing detail of the method to provide replaceable threaded rod supports  249 . Location where cross Section C-C is taken is shown in  FIG. 32B . Location where cross Section C-C is taken is shown in  FIG. 32B  with the middle element in the raised position when lifting a roof structure, and the middle element in the lowered position when lifting an entire structure. 
       FIG. 30B  shows a detailed cross Section B-B of outer element  230 C of lifting element  230  showing the detail of the method to provide and retain replaceable threaded rod supports  249 . Location where cross Section B-B is taken is shown in  FIG. 29 . 
       FIG. 30C  shows a detailed cross Section C 1 -C 1  of outer element  230 C and middle element  230 B of lifting element  230  showing detail of the method to provide replaceable threaded rod supports  249 . Location where cross Section C 1 -C 1  is taken is shown in  FIG. 32B  with the middle element in the lowered position when lifting a roof structure, and in the middle element in the raised position when lifting an entire structure. 
       FIG. 30D  shows a detailed cross Section D-D of middle element  230 B of lifting element  230  showing detail of the method to provide replaceable threaded rod supports  249 . Location where cross Section D-D is taken is shown in  FIG. 29  with the middle element  230 B in the raised position when lifting a roof structure, and the middle element  230 B in the lowered position when lifting an entire structure. 
     A drive block attached is to the threaded lifting rod  1406  that elevates the extending portion  234 B when raising a roof structure or pushes downward extending portion  234 B when raising an entire structure as the threaded lifting rod  1406  is rotated. The extending portion  234 B is driven a pre-determined distance and then pinned at that location via a cotter pin that slides through the main tube and extending portion. After the inner extending portion  234 B is pinned, replaceable threaded rod supports  249  are installed through holes in outer tube  230 C of lifting element assembly  230 . A length of tubing  230 D is utilized to secure and retain replaceable threaded rod supports  249 . One or more than one set of replaceable threaded rod supports  249  and section of tube  240 D may be used per lifting element assembly  230 . 
       FIG. 31A  shows detailed cross Section E-E of lifting element assembly  230  showing the detail of the method to retain the replaceable threaded rod supports  249  with section of tubing  230 D in its normal position. Two differently sized non-metallic slider blocks  241 A and  241 B are inserted in holes in tube section  240 D, and make contact with replaceable threaded rod supports  249 , thereby serving as a ‘stop’ and limits the vertical travel of tube section  240 D.  FIG. 31B  is a detailed cross section of lifting element assembly  230  showing the detail of the method to retain the replaceable threaded rod supports  249  with section of tubing  230 D in its normal position.  FIG. 31B  identifies where Section E-E is taken. 
       FIG. 32A  shows detailed cross Section F-F of lifting element assembly  230  with section of tubing  230 D in its raised position to install or replace replaceable threaded rod supports  249 .  FIG. 32B  identifies where Section F-F is taken. 
     The various elements of this apparatus can be made of steel or other suitable materials. These can include aluminum and other metals. Selection of materials is based on the likely loads each element would encounter during the lifting process. In this manner, certain materials can be chosen for their compressive or tensile strength and weight. Composite materials can also be used; the lightweight and high strength of these materials may be optimal, but must be weighed against the cost of manufacturing the various elements. Additionally, each element of this apparatus is reusable, making this system easy to install and remove on multiple building sites. Due to the modular nature of this system, it can be expanded to fit a building of many sizes. 
     Having described and illustrated the principles of the disclosed technology in a preferred embodiment thereof, it should be apparent that the disclosed technology can be modified in arrangement and detail without departing from such principles. We claim all modifications and variations coming within the spirit and scope of the following claims

Summary:
A system and method for raising a structure, or part thereof, the system comprising vertical jack members connected and disposed about a rail system attached about the periphery of the structure. The vertical jack members comprise an outer sleeve and a slidable inner portion that is driven vertically by a jack screw and drive block. Extensible diagonal cross-braces stabilize the jack members and structure being raised.