Abstract:
The present invention relates to panelized log home construction. In a first embodiment, a wall panel comprises a plurality of logs of predetermined length stacked on top of each other. A tongue is machined into each log end such that when stacked a wall tongue is formed from the aligned log tongues. A rod channel runs through the stacked logs for receiving a tension/lifting rod. A first end of the tension/lifting rod comprises a rod lifting attachment for lifting and adjustment of the tensioning force. Optional protective coverings fixedly cover each wall tongue and optional wall utility channels receive wires and pipes, as required. A pair of posts fixedly attached to a foundation slidably receive the wall panels. Machined into each post is at least one wall receiving groove sized to slidably receive and cooperate with the wall tongue. An optional protective groove insert fixedly covers each wall receiving groove to lessen the possibility of post breakage upon wall panel insertion.

Description:
FIELD OF THE INVENTION  
       [0001]     This invention relates generally to log home construction and in particular, to panelized log home construction.  
       BACKGROUND OF THE INVENTION  
       [0002]     Log cabins have been used as shelter for hundreds of years. The earliest methods of constructing these shelters utilized round logs notched near the corners to provide structural integrity to the completed building as the logs were stacked. Still used today, this method of construction is extremely labor intensive, difficult to fabricate, often drafty, and requires a high level of maintenance.  
         [0003]     Stacking round logs results in a relatively small surface area of log to log contact. In order to produce a continuous wall with a reasonable level of thermal and structural integrity, an adhesive material is packed into the horizontal space between logs, a process know as chinking. These walls are referred to as “chinked walls”. Chinked walls require continuous maintenance as the chinking is lost over time and must be replaced.  
         [0004]     To reduce or eliminate the necessity for chinking, improved methods of log cabin construction have been developed. One such method involves logs with flattened sides and square notches. When stacked, the flat sides are closer together than rounded sides, minimizing the need for chinking.  
         [0005]     The next evolution in log cabin construction utilized a scribing of one log of a wall to approximately match the contour of the log upon which it rested, thereby bringing the logs into more intimate contact. This intimate contact required only minimal chinking, or alternatively, caulking.  
         [0006]     Additional developments to create better structural integrity and increased thermal efficiency have included flattened tops and bottom log surfaces to further increase contact surface area, and the addition of one or more tongues in one of the log faces to cooperate with and fit within corresponding grooves in the flat face of an adjacent log.  
         [0007]     While these improvements have contributed to more structurally sound, energy efficient structures, other problems still remain. For example, logs which comprise the log structure tend to shrink in width even if they have been kiln dried prior to placement. This shrinkage, reported to be as much as 1 inch per log, contributes to increased draftiness and water leakage. Additionally, stacked logs settle as they shrink, reducing the overall height of the wall and thereby affecting the position of any structures supported by the wall. Such structures may include doors and windows which become out of square and roof trusses which become uneven.  
         [0008]     Still another problem inherent in log cabins built by the above identified construction methods is the difficulty to effectuate major repairs to a wall section damaged by, for example, a fire or flood. Cutting out and replacing a section of damaged wall with acceptable cosmetic results is both labor and time intensive, with resultant high repair costs.  
         [0009]     One construction method used to overcome both the shrinkage and wall section replacement problems is to utilize a wall panel comprising horizontal sections of logs stacked between and held in place by two upright support elements. Such an arrangement provides a means for supporting a load above the upper edge of the wall panel regardless of vertical movement between the upper edge of the uppermost horizontal log and the load and allows for relatively easy replacement of a damaged wall panel section.  
         [0010]     One example of such a wall panel is U.S. Pat. No. 5,265,390 to Tanner. Tanner&#39;s wall panel comprises a base plate, a plurality of horizontally placed wooden logs independently held between a pair of standards and at least one jack mounted on the upper edge of each wall panel. The logs mate with one another without being fixed together so that each log can move separately relative to the standards.  
         [0011]     While Tanner&#39;s wall panel presents advantages over non-panelized construction methods, problems still remain. Chief among them are the requirement to assemble the wall panel onsite. Accordingly, there is still a continuing need for improved methods to construct log cabins. The present invention fulfills this need, and further provides related advantages.  
       BRIEF SUMMARY OF THE INVENTION  
       [0012]     The present invention relates to panelized log home construction. In a first embodiment, a wall panel comprises a plurality of logs of predetermined length stacked on top of each other. A tongue is machined into each log end such that when stacked a wall tongue is formed from the aligned log tongues. A rod channel runs through the stacked logs for receiving a tension/lifting rod. A first end of the tension/lifting rod comprises a rod lifting attachment for lifting and a second end permits adjustment of the tensioning force. Optional protective channels fixedly cover each wall tongue and optional wall utility channels receive wires and pipes, as required.  
         [0013]     In a second embodiment, a pair of posts fixedly attached to a foundation slidably receive the wall panels. Machined into each post is at least one wall receiving groove sized to slidably receive and cooperate with the wall tongue. An optional protective groove covering fixedly covers each wall receiving groove to lessen the possibility of post breakage upon wall panel insertion.  
         [0014]     According to a third embodiment, a method of constructing a wall panel comprises the steps of stacking a plurality of logs of predetermined length on top of each other; machining a tongue into each log end such that when stacked a wall tongue is formed from the aligned log tongues; fabricating a rod channel through each log such that when stacked a rod channel runs through the wall panel to receive a tension/lifting rod, a first end of the tension/lifting rod comprising a rod lifting attachment for lifting and a second end permitting adjustment of the tensioning force; and placing a predetermined tensioning force on the stacked walls. Optionally, a protective tongue covering is fixedly attached to each wall tongue and optionally a utility channel is machined into each log such that when stacked, a wall utility channel is formed for receiving wires and pipes, as required.  
         [0015]     According to a fourth embodiment, a log home comprises a plurality of wall panels and posts in a predetermined arrangement.  
         [0016]     According to a fifth embodiment, a method of repairing a damaged wall panel comprises the steps of removing an effective amount of wall panel cover structure to permit the damaged wall panel to be slidable removed; slidably inserting a replacement wall panel; and repairing the wall panel cover structure, wherein the wall panel comprises a plurality of logs of predetermined length stacked on top of each other; a tongue is machined into each log end such that when stacked a wall tongue is formed from the aligned log tongues; a rod channel runs through the stacked logs for receiving a tension/lifting rod, a first end of the tension/lifting rod comprising a rod lifting attachment for lifting and a second end permitting adjustment of the tensioning force; and a pair of posts fixedly attached to a foundation to slidably receive the wall panels, wherein each post includes at least one wall receiving groove sized to slidably receive and cooperate with the wall tongue.  
         [0017]     One advantage of the panelized log home construction of the present invention is the ability to easily and relatively inexpensively remove a panel section to repair major damage caused by, for example, fire or flood.  
         [0018]     Another advantage is that the wall panel may be constructed off-site under controlled climatic conditions and then easily transported to the construction site.  
         [0019]     Still another advantage is the reduced on-site construction time with concomitant cost savings on labor.  
         [0020]     Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiments, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]      FIG. 1  is an oblique view of a panelized wall.  
         [0022]      FIG. 2  is an oblique view of a log.  
         [0023]      FIG. 3  is an oblique view of a panelized wall system.  
         [0024]      FIG. 4  is a cross sectional view of a portion of a panelized wall.  
         [0025]      FIG. 5  is a front view of a panelized wall system.  
         [0026]      FIG. 6  is a top view of a post retaining two panelized walls.  
         [0027]      FIG. 7  is a top view of a corner post.  
         [0028]      FIG. 8  is a cross sectional view of ship lapped stacked posts.  
         [0029]      FIG. 9  is a cross sectional view of a panelized wall system in place. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0030]     The present invention will be described in relation to log homes. However, it should be appreciated that the materials described are not limited to wood. Any material suitable for construction may be substituted, for example, metal such as steel and aluminum, composites, extruded wood replacement materials and the like. Furthermore, the present invention is not limited to any particular wood shape or size, nor to any particular building shape. The dimensions described below are used merely as exemplars.  
         [0031]     Turning now to the figures, and more specifically  FIGS. 1-3 , wall panel  2  of the present invention comprises a plurality of logs  4  cut to a finished face dimension plus the depth of wall receiving groove  52 , cut into each of two posts  48 , described in detail below. Tongue  6  is machined into each end of log  4  such that when stacked wall tongue  84  is formed from aligned log tongues  6 . Optionally, but preferably, log  4  has a second tongue  10  machined into a first horizontal surface  12  and a cooperating groove  16  machined into a second horizontal surface  14 , such that when logs  4  are stacked, second tongue  10  and groove  16  cooperate in a known manner.  
         [0032]     At least one rod channel  20  is drilled into log  4  from first horizontal surface  12  to second horizontal surface  14  to receive tension/lifting rod  22  in stacked logs  4 . Preferably two rod channels  20  are drilled at equal distance from the centerline of log  4 . Optional utility channel  24  is drilled at a predetermined location so that when logs  4  are stacked, wall utility channel  26  is formed to receive, for example, electrical conduit, water pipe, gas pipe or combinations thereof. If required, utility slot  28 , is cut into log  4  to receive, for example, an electrical box (not shown). Utility channel  24  may be cut horizontally into log  4 , as required.  
         [0033]     Turning to  FIG. 4 , logs  4  are assembled into a wall panel by stacking and fixing one log  4  on top of another. Seal  30  is placed between each fixedly stacked log  4 . In a preferred embodiment, logs  4  are fixedly attached by running adhesive bead  32  along either side of second tongue  10 , and seal  30  is created by running insulation bead  34  on top of second tongue  10  prior to stacking. Insulation bead  34  is formed of material that does not interfere with the adhesive process, for example, a high expansion insulation material, rubber gasket, or felt. To provide additional fixation, each log  4  is attached to the log  4  on which it rests with, for example, log screw  36 , preferably, a 10″ log screw at 12″ centers. This stacking process is repeated until the design height of panel  2  is obtained.  
         [0034]     Shown in  FIG. 5 , logs  4  may be stacked onto tension/lifting rod  22  as wall panel  2  is being assembled by inserting tension/lifting rod  22  into successive rod channels  20 ; tension/lifting rod  22  may be inserted into wall rod channel  38  formed by stacked rod channels  20  after wall panel  2  has been assembled; or wall panel  2  may be assembled partly with tension/lifting rod  22  inserted after log  4  stacking and partly with logs  4  stacked after tension/lifting rod  22  is in place, dependant on assembly physical space limitations. Tension/lifting rod  22  is, for example, a ½ inch to ⅝ inch diameter threaded high tensile steel rod. Rod lifting attachment  62 , for example, eye loop  64  is threaded onto the lifting end  23 .  
         [0035]     To provide adjustable tension, tension/lifting rod non-lifting end  66  is, for example, threaded into nut  40  welded onto plate  68 . Second nut  41  is threaded onto lifting end  23  and countersunk into uppermost log  4 . Tension/lifting rod  22  is tightened to an effective force to create an effective seal and minimize cracking of logs  4 . As required, electrical conduit, electrical wire, and/or pipe (not shown) is installed in wall utility channel  26 , and electric box (not shown) installed in utility slot  28 . Either bottom log  4  of wall panel  2  or base log  70  ( FIG. 3 ) is countersunk to receive nut  40  and plate  68 , thereby allowing panel  4  to rest flush upon base log  70 . The interface of wall panel  2  and base log  70  also receives seal  30  and adhesive bead  32  in the manner described above.  
         [0036]     Turning to  FIG. 6 , optionally, in a preferred embodiment protective tongue covering  42 , for example, a steel channel, shaped to intimately receive wall tongue  84  is installed over wall tongues  84 . Protective tongue covering  42  is installed by, for example, drilling holes to receive ¼″ by 4″ screws  50  at 8″ centers. Screws  50  have tapered heads to maintain a flush or smooth finish to protective tongue covering  42 . Prior to installation, seal  30  is placed under protective tongue covering  42  in the manner described above.  
         [0037]     Returning to  FIG. 3 , panel openings  44 , for example, window and door openings, are cut and framed into wall panel  2  as wall panel  2  is assembled. Alternatively, panel openings  44  may be cut and framed after wall panel  2  has been assembled. Panel openings  44  are framed by installation of, for example, jacks  46 , preferably 2×4 inch jacks, adjusted to the rough opening of the window or door unit (not shown) to be installed.  
         [0038]     It should be appreciated that prefabricated wall panels  2  may be constructed off site under controlled climatic conditions, thereby providing better quality control, tighter tolerances, and reduction in on site labor costs. Tension/lifting rods  22  and optional protective tongue covering  42  also serve to keep wall panel  2  from bowing as it is raised from a horizontal storage or transport position.  
         [0039]     Turning now to  FIGS. 6 and 7 , post  48  is fabricated with at least one wall receiving groove  52  machined along its length. Intermediate post  54  ( FIG. 6 ) has two wall receiving grooves  52  machined into opposite sides, while corner post  56  ( FIG. 7 ) has two wall receiving grooves machined into, for example, 90 degree sides. In a preferred embodiment, corner post  56  is fabricated from a minimum of 8″×8″ cut stock.  
         [0040]     Optionally, but preferably, protective groove insert  58 , for example, a steel covering shaped to intimately receive protective tongue covering  42  is installed within wall receiving groove  52 . Groove insert  58  is installed by, for example, drilling holes to receive ¼″ by 4″ screws  50  at 8″ centers. Screws  50  have tapered heads to maintain a flush or smooth finish to receiving groove  52 . Prior to installation, seal  30  is placed under groove insert  58 , in the manner described above.  
         [0041]     Turning again to  FIG. 3 , posts  48  are conventionally fastened to foundation  76 , for example, with L lags (not shown), preferably, ¼″×6″ L lags or with dowels  74 , or combinations thereof. Depending on local building codes, posts  48  may be fastened directly to foundation  76 , or alternatively to sill plate  78  which has been fastened to foundation  76 .  
         [0042]     After installation of posts  48 , wall panel  2  is raised by rod lifting attachments  62  and aligned such that tongue  6  (preferably protected by protective tongue covering  42 ) aligns with post groove  60  (preferably protected by post groove insert  58 ) and slidably lowered into place. Although wall panel  2  may rest directly upon foundation  76  or sill plate  78  (as required by local code), in a preferred embodiment, at least one base log  70 , countersunk to receive tension/lifting rod nut  40 , is mounted to foundation  76  or sill plate  78  (as required by local code) prior to placement of wall panel  2 . Thereafter, wall panel  2  is slidably mounted as described above and rests upon base log  70 .  
         [0043]     Once wall panel  2  is in place, rod lifting attachment  62  is removed. If desired, tension/lifting rod  22  may be cut flush with counter sunk second nut  41 . However, it is preferable to bore out the bottom log  4  of a second stacked wall panel  2 , or the top plate  86 , for example, a lentil log, as applicable, to accept the extended tension/lifting rod  22 . In this manner, rod lifting attachment  62  may be reattached if wall panel  2  needs to be subsequently removed.  
         [0044]     Maximum wall panel  2  dimensions are limited only by the ability to transport, lift and position wall panel  2 . Wall panels  2  may be stacked utilizing, for example, dowels  74  or pins, and adhesive bead  32  with a through lag bolt or screw (not shown) from the opposite side of post  48  installed into stacked wall panel  2 . Posts  48  may be likewise stacked using for example, dowels  74  or pins, and adhesive bead  32 . As shown in  FIG. 8 , when staked, bracket  78  is mounted within and to span mating post wall receiving grooves  52 , using, for example, screws. Optionally, posts may be mated using s shiplap joint  82 . Once wall height has been established, top plate  86  ( FIG. 3 ) is constructed using known construction methods, supported by posts  48 .  
         [0045]     Turning to  FIG. 9 , wall panel  2  or base log  70 , as required by local code, rests on only a portion of sill plate  78 . In a preferred embodiment, floor joist  90  is supported by at least a portion of remaining sill plate  78 . In this manner, floor joists  90 , floor decking  92 , and insulation  94  may be constructed after wall panels  2  have been placed. Drip edge  88 , is constructed between sill plate  78  and foundation  76 .  
         [0046]     A plurality of wall panels  2  and posts  48  placed in a predetermined pattern form the log home (not shown). By utilizing the panelized log home construction of the present invention, onsite framing time has been reduced from six to seven months down to five to ten days. Similarly, the time required to replace a damaged wall section has been dramatically reduced.  
         [0047]     To repair a damaged wall section, the roof and overlying floor (if present) are cut away a sufficient amount to allow wall panel  2  to be lifted out after cutting the appropriate adhesive bead  32  and replaced with an undamaged or repaired wall panel  2 . If a repaired wall panel  2  is used, a replacement tongue  6  is added, if required. Rafters and joists that have been cut away to provide lifting access are repaired using known “sistering” or similar construction techniques, followed by repair of the floor and roof.  
         [0048]     Although the present invention has been described in connection with specific examples and embodiments, those skilled in the art will recognize that the present invention is capable of other variations and modifications within its scope. For example, in the exemplar, protective tongue covering  42  and protective groove covering  58  are utilized to prevent breakage of post  48  during installation of wall panel  2 . However, depending on the strength of construction materials used, one or both could be omitted.  
         [0049]     These examples and embodiments are intended as typical of, rather than in any way limiting on, the scope of the present invention as presented in the appended claims.