Patent Publication Number: US-7594367-B2

Title: Connection structure for a log wall

Description:
This application is a divisional of prior U.S. application Ser. No. 10/372,854, filed Feb. 26, 2003, which is hereby incorporated herein by reference. 

   FIELD 
   This invention relates to construction systems for constructing log structures such as houses, cabins, and the like, and more particularly to connection structures for connecting, for example, logs to a post. 
   BACKGROUND 
   Homes or cabins built of logs are often considered desirable for their aesthetics. However, constructing such log structures can present a number of difficulties. For example, it can be difficult to provide corner connection of logs at an intersecting corner that is strong and weather tight, both at initial installation and after the log walls have settled over time. 
   A known corner connection structure is disclosed in U.S. Pat. No. 5,020,289 (Wrightman). The corner connection of Wrightman provides a dovetail joint between the intersecting logs, and a pair of splines having a ‘figure- 8 ’ cross-sectional profile. However, the structural elements themselves leave seams through which the weather could penetrate. Caulking could be provided for weather-proofing, but caulking has a limited lifespan, and could work loose during natural settling and shrinkage of the logs. Alternatively, gaskets could be provided between the mating faces of the dovetails, but gaskets can be relatively costly and time-consuming to install. 
   Another corner connection structure is disclosed in U.S. Pat. No. 4,353,191 (Schilbe). The corner connection structure of Schilbe has an obliquely disposed mortise provided adjacent the intersecting region of logs at a corner, and a wooden locking section placed in the mortise. However, by providing the mortise adjacent the intersecting region, rather than within the intersecting region, the locking member is engaged only at its outer ends by the mortise, which may limit the strength and support provided by the locking member. Furthermore, Schilbe does not address the natural settling of the logs that takes place over time. The fit between the mortise and the locking member, as taught by Schilbe, must be sufficient to prevent horizontal movement of the logs relative to the locking member. However, such a tight fit would also inhibit vertical movement of the logs relative to the locking member, which could result in gaps forming between the logs along the height of the walls at the intersecting corner. The weather may then penetrate the corner structure, and moisture could collect within the log structure, between the inside of the walls and the locking member. 
   Providing through-bolts at corners or at intermediate positions along the lengths of log walls can provide additional strength and support for the walls. Known through-bolt devices are described in U.S. Pat. No. 4,503,647 (Post) and U.S. Pat. No. 4,688,362 (Pedersen et al.). In both of these references, the through-bolt devices include through-bolts extending along the height of the walls, and regular hex nuts at the lower end of the through-bolts for tightening the devices. These devices require access to the hex nuts for wrenches or other tools when assembling or adjusting the through-bolt devices. However, providing such access may be difficult, and may require, for example, fairly large openings cut into the lower sides of the walls. Specially cut panels may then be required to conceal the openings. 
   It is often convenient in walls constructed of logs that two shorter logs be joined end-to-end to span the length of the wall. A butt joint for connecting logs end-to-end is disclosed in the patent to Wrightman, already noted above. The butt joint according to Wrightman has a two-piece spline with semi-circular lobes on one face and opposing passages on the opposite face. Spikes are driven into the passages to expand the two-piece spline, and provide an interference fit between the lobes of the spline and matching recesses provided in the logs. This butt joint is fairly complex and may be time consuming to assemble. Furthermore, the simultaneous alignment of the passageways and the lobes within the recesses may be difficult to achieve. 
   Another butt joint is disclosed in U.S. Pat. No. 4,279,108 (Collister, Jr.). The butt joint of Collister Jr. has plastic weather deflectors inserted into a slot, which spans the seam between the adjacent end faces of the logs to be joined. Compressible gasket strips are also provided between the end faces of the adjacent logs. Since no structural joint element engages the logs in a transverse direction, it may be difficult to ensure that the logs connected by this joint are in fact locked to inhibit longitudinal movement. Furthermore, since the gasket strips are installed prior to fixing the logs together, the strips may be damaged during positioning and assembly of the logs. 
   Openings are often desirable in log walls to accommodate windows, doors, and the like. It may be advantageous to provide special support structures at such openings to facilitate building the walls around the opening, and to provide a suitable mounting means for the structural framing elements of the window or door to be subsequently installed. A known opening support structure is disclosed in U.S. Pat. No. 4,224,772 (Bene et al.). Bene et al. discloses a connection member disposed between the log end faces at the opening and the frame member of a window to be installed in the opening. The connection member is attached to the logs by nails driven through slots in the connection member and into the end grain of the logs, so that relative vertical movement between the connection member and the logs is possible. The frame member of the window is in turn secured to the connection member. Using nails driven into the end grain of the logs may not, however, provide a secure joint because the nails may work loose as the fibers of the wood separate. Furthermore, shrinkage of the logs over time may compromise the strength of the support structure. 
   In building log walls, the logs themselves can be provided with a particular profile to facilitate alignment of the logs during construction and to increase the strength of the wall. In the above-noted Wrightman patent, a log profile is disclosed in which the tongues and grooves are provided in the upper and lower surfaces of the logs, respectively. The upper and lower surfaces of vertically adjacent logs fit together, providing a seam across the width of the logs. However, at either side of the logs, the profile provides a generally horizontal seam portion which could collect moisture and cause associated wood preservation difficulties. 
   Another log profile is disclosed in U.S. Pat. No. 3,440,784 (Onjukka). The profile taught by Onjukka has matching tongues and grooves in the upper and lower surfaces of vertically adjacent logs. However, no provision is made for installing seals along the seam between adjacent logs, at a point along the seam between the outer horizontal edges. Accordingly, the weather-proofing of the interface between adjacent logs may be compromised, particularly as the logs shrink and settle over time. 
   In some log structures having walls constructed of stacked horizontal logs, it can be advantageous to provide vertical posts at the corners of intersecting walls, as well as at intermediate points along the length of a wall. A post-to-log connection structure can be provided for connecting the end faces of the logs to a vertical surface along the post. A known post-to-log connection structure is disclosed in U.S. Pat. No. 4,742,033 (Veech), wherein a vertical spline is inserted into corresponding slots provided in the end faces of the logs and the surface of the post. However, no adjustable fastening means is provided for drawing the post and log ends snugly together. 
   SUMMARY 
   The following summary is intended to introduce the reader to this specification but not to define any invention. In general, this specification discusses one or more methods or apparatuses related to constructing log structures. Aspects of the teaching provided herein by the applicants include, but are not limited to, corner connection structures, through-bolt clamping apparatuses, logs with particular log profiles, log support structures, exterior casing structures, butt-joint connection structures, log connection structures, and joint sealing structures. 
   Various apparatuses or processes are described herein to provide an example of an embodiment of each claimed invention. No embodiment described below limits any claimed invention and any claimed invention may cover processes or apparatuses that are not described below. The claimed inventions are not limited to apparatuses or processes having all of the features of any one apparatus or process described below or to features common to multiple or all of the apparatuses described below. It is possible that an apparatus or process described below is not an embodiment of any claimed invention. The applicants, inventors or owners reserve all rights that they may have in any invention disclosed in an apparatus or process described below that is not claimed in this document, for example the right to claim such an invention in a continuing application and do not intend to abandon, disclaim or dedicate to the public any such invention by its disclosure in this document. 
   According to one aspect, a connection structure for a log wall is provided, the connection structure comprising: (a) a plurality of logs extending horizontally in an axial direction and stacked vertically to form a wall, the logs each having an end face at one end thereof, the end faces of the logs being generally vertically aligned with each other and defining an edge surface of the wall; (b) a plurality of connectors retained within the wall adjacent the edge surface of the wall; (c) a plurality of fastener access passageways in the wall, each fastener access passageway extending between a respective connector and the edge surface of the wall; and (d) a plurality of fasteners, each fastener extending through a respective fastener access passageway and having a first end coupled to a respective connector and a second end opposite the first end, the second end extending proud of the edge surface of the wall. 
   In some embodiments, the connectors can extend between vertically adjacent pairs of the plurality of logs, each pair of logs including a respective lower log and an upper log generally situated on top of the lower log, each connector having a connector body with a lower and an upper log engagement portion, each lower log engagement portion engaging the respective lower log, and each upper log engagement portion engaging the respective upper log. 
   In some embodiments, each respective lower log can comprise a top surface and each respective upper log can comprise a bottom surface generally facing the top surface of each respective lower log, each top surface having an upper connector aperture extending therefrom and into the respective lower log for receiving the lower log engagement portion of the respective connector, and each bottom surface having a lower connector aperture extending therefrom and into the respective upper log for receiving the upper log engagement portion of the respective connector. 
   In some embodiments, the fastener access passageway can comprise a depression in at least one of the top surfaces of the respective lower logs and the bottom surfaces of the respective upper logs, the at least one depression extending from a respective connector aperture to a respective end face of the log. Each connector can be spaced axially apart from the edge surface to provide a load bearing portion of each respective log between the connectors and the end faces. 
   In some embodiments, the connection structure can include a plurality of brackets, each bracket coupled to a respective fastener adjacent the second end thereof. The connection structure can comprise a post coupled to the brackets and having a generally vertical joint face in abutment with the end faces of the logs, the fastener being adjustable to securely draw together the logs and the post. The post can have a channel in the joint face of the post, the channel extending vertically along the height of the post, and wherein the bracket is vertically slidable within the channel. The channel can include a bracket housing portion spaced axially away from the joint face and a slot portion extending between the joint face and the bracket housing portion, the bracket being slidably retained in the bracket housing portion and the fastener extending through the slot portion. The housing portion can comprise shoulders extending laterally outward from the slot portion, and the bracket can have laterally extending clamp arms that bear against the shoulders 
   According to another aspect, a connection structure is provided, the structure comprising: (a) a plurality of horizontally extending, vertically stacked logs forming a wall, the logs defining an axial direction along their lengths, the logs each having an end face at one end thereof, the end faces of the logs being generally vertically aligned with each other; (b) a post having a generally vertical joint face in abutment with the end faces of the logs; and (c) at least one link assembly for coupling at least one of the logs to the post, each link assembly including a connector anchored in the at least one log and a bracket anchored in the post and coupled to the connector, the bracket being vertically slidable relative to the post. 
   In some embodiments, the link assembly can comprise a fastener extending between the bracket and the connector. The fastener can be adjustable for adjusting the spacing between the bracket and the connector. 
   In some embodiments, the connection structure can include a channel in the joint face of the post, the channel extending vertically along the height of the post, and the bracket being vertically slidable within the channel. The channel can comprise a bracket housing portion spaced axially away from the joint face and a slot portion extending between the joint face and the bracket housing portion, the bracket being slidably retained in the bracket housing portion and the fastener extending through the slot portion. The housing portion can comprise shoulders extending laterally outward from the slot portion, and the bracket can include laterally extending clamp arms that bear against the shoulders. The clamp arms can comprise flange portions obliquely aligned relative to each other, and the retaining shoulders can comprise obliquely aligned contact surfaces for providing generally flush contact with the flange members of the bracket. 
   The fastener can comprise a bolt having a first end coupled to the connector and a second end opposite the first end and coupled to the bracket. The connecter can have a cross bore extending generally horizontally through the connector and through which the fastener extends, the cross bore having a counter-bored portion directed away from the bracket, the head of the bolt being seated in the counter-bored portion. The bracket can comprise a threaded member for engaging the threaded portion of the bolt, the threaded member being fixed against rotation relative to the bracket, and the bracket being fixed against rotation relative to the post. 
   According to another aspect, a connection structure for a log wall is provided, the structure comprising: (a) a plurality of horizontally extending, vertically stacked logs forming a wall, the logs defining an axial direction along their lengths, the logs having generally vertically aligned end faces at one end thereof; (b) a post having a generally vertical joint face in abutment with the end faces of the logs; (c) a plurality of connectors positioned in the wall adjacent the post, each connector having a connector body with a lower and an upper log engagement portion, each lower log engagement portion engaging a respective lower log in the wall, and each upper log engagement portion engaging a respective upper log in the wall, each upper log being positioned vertically above each lower log, respectively; (d) a plurality of brackets retained within the post, each bracket generally positioned in horizontal registration with a respective connector; and (e) a plurality of fasteners, each fastener extending between a respective connector and bracket for coupling together the respective connector and bracket. 
   According to another aspect, a connection structure for a log wall includes a bracket coupled to a post, wherein the bracket is vertically slidable relative to the post, a connector positioned within the wall adjacent the post, a fastener access passageway extending through the wall between the bracket and the connector, and a fastener extending through the fastener access passageway, wherein the fastener is coupled to the bracket and to the connector, and is adjustable to draw the logs snugly against the post. 
   The connector may have a connector body with lower and upper log engagement portions, wherein the lower engagement portion engages a log in one course, and the upper engagement portion engages a log in a course vertically above the log engaged by the lower log engagement portion. 
   The logs adjacent the post may have top surfaces provided with upper connector apertures adapted to receive the lower log engagement portions of the connectors, and bottom surfaces provided with lower connector apertures adapted to receive the upper log engagement portions of the connectors. The outer profiles of the connectors may be adapted to provide interspersed areas of contact and areas of non-contact between the outer surface of the connectors and the inner surface of the connector apertures. 
   Each fastener may be a bolt having at opposite ends a head and a threaded portion, and the connectors may be provided with a generally horizontal bore shaped to engage with the head of the bolt. A hex nut may be coupled with the threaded portion of the bolt, and a locking pin may extend transversely from the nut and engage the bracket. 
   Opposed depressions may be provided in the top and bottom surfaces of the logs, the depressions adapted to cooperate to form the fastener access passageways. The opposed depressions may be v-grooves. The post of the post-to-log connection structure may be provided with a generally vertical channel abutting the logs, and the bracket may be vertically slidable within the channel. The channel may have generally transverse retaining lips, and the bracket may have clamp arms in engagement with the retaining lips. 
   The clamp arms of the brackets may be obliquely aligned flange members, wherein the spacing between the flange members converges from a wider spacing away from the connectors, to a narrower spacing nearer the connectors. The retaining lips may have obliquely aligned contact surfaces for providing generally flush contact with the flange members of the bracket. 

   
     DESCRIPTION OF THE DRAWINGS 
     For a better understanding of the applicant&#39;s teaching and to show how it may be carried into effect, reference will now be made by way of example, to the accompanying drawings in which: 
       FIG. 1  is a perspective view of a portion of two intersecting walls having, in accordance with examples of the applicant&#39;s teaching, a corner connection structure, a through-bolt clamping apparatus, logs with a particular log profile, an opening support structure, an exterior casing structure, and a butt-joint connection structure; 
       FIG. 2  is a perspective view showing the corner connection structure of  FIG. 1  in greater detail; 
       FIG. 3   a  is side view of a portion of a log used in the connection structure of  FIG. 2 ; 
       FIG. 3   b  is an end view of the portion of the log shown in  FIG. 3   a ; 
       FIG. 4  is an elevation view of the corner connection structure of  FIG. 1 , in combination with a through-bolt clamping apparatus; 
       FIG. 5  is a top view of two logs of the corner connection structure of  FIG. 1 ; 
       FIG. 6  is an exploded view of the logs shown in  FIG. 5 ; 
       FIG. 7  is an enlarged view of one of the logs shown in  FIG. 6 ; 
       FIG. 8  shows the logs of the corner connection structure of  FIG. 5  in combination with a corner spline according to the present invention; 
       FIG. 8   a  is an enlarged view of a portion of  FIG. 8 ; 
       FIG. 9   a  is a perspective view of a corner spline according the present invention; 
       FIG. 9   b  is a side view of the spline of  FIG. 9   a ; 
       FIG. 10  is an elevation view of an alternative embodiment of a corner spline for use with a corner connection structure of the present invention; 
       FIG. 11  is a perspective view of an alternative embodiment of a corner spline for use with a corner connection structure of the present invention; 
       FIG. 12  is an exploded view of the through-bolt clamping apparatus of  FIG. 4 ; 
       FIG. 13  is a top view of a corner spline shown in  FIG. 12 ; 
       FIG. 14  is a bottom view of a lowermost log of the corner connection structure of  FIG. 1 ; 
       FIG. 15  is an exploded view of an alternative embodiment of a portion of the apparatus of  FIG. 12 ; 
       FIG. 16  is a portion of the elevation view of  FIG. 4 , in combination with the apparatus of  FIG. 15 ; 
       FIG. 17  is a front elevation view of another embodiment of a through-bolt clamping apparatus according to the present invention; 
       FIG. 18  is an exploded view of the apparatus of  FIG. 17 ; 
       FIG. 19  is a side elevation view of the apparatus of  FIG. 17 ; 
       FIG. 20  is an exploded view of an alternative embodiment of a portion of the apparatus of  FIG. 17 ; 
       FIG. 21  is a front elevation view of  FIG. 20  in combination with the apparatus of  FIG. 17 ; 
       FIG. 22  is a cross-sectional view of the log profile of  FIG. 1 ; 
       FIG. 23  is a cross-sectional view of one log of  FIG. 22  stacked upon another; 
       FIG. 24  is a cross-sectional view of an alternative embodiment of a log profile according to the present invention; 
       FIG. 25  is a cross-sectional view of one log of  FIG. 24  stacked upon another; 
       FIG. 26  is a front elevation view of the wall opening support structure of  FIG. 1 ; 
       FIG. 27  is a perspective view showing a portion of the structure of  FIG. 26  in further detail; 
       FIG. 28   a  is a side view of a support block of  FIG. 27 ; 
       FIG. 28   b  is a side view of another support block of  FIG. 27 ; 
       FIG. 29  is a perspective view of the structure of  FIG. 26  showing further details; 
       FIG. 30  is a side elevation view in cross-section of a portion of the structure of  FIG. 26 ; 
       FIG. 31  is a top sectional view of a portion of the structure of  FIG. 26 ; 
       FIG. 32  is a top sectional view of a sub-jamb member of  FIG. 29 ; 
       FIG. 33  is a front elevation view of the sub-jamb member of  FIG. 32 ; 
       FIG. 34  is a perspective view showing further details of the opening support structure and exterior side casing structure of  FIG. 1 ; 
       FIG. 35  is a cross-sectional view of a portion of the exterior side casing structure of  FIG. 34 ; 
       FIG. 36  is a top view of the exterior casing structure of  FIG. 34 ; 
       FIG. 37  is an exploded perspective view of the butt joint connection structure of  FIG. 1 ; 
       FIG. 38  is a top view of portions of the butt joint connection structure of  FIG. 1 ; 
       FIG. 39  is a top view of a spline of the butt joint connection structure of  FIG. 1 ; 
       FIG. 40  is a top cross-sectional view of the butt joint connection structure of  FIG. 1 ; 
       FIG. 41  is a section view of  FIG. 40  taken along the line  41 - 41 ; 
       FIG. 42  is an exploded perspective view of an example of a connection structure according to the applicant&#39;s teaching; 
       FIG. 43  is an exploded view of a component of the of the connection structure of  FIG. 42 ; 
       FIG. 44  is a top view of the connection structure of  FIG. 42 ; 
       FIG. 45  is a perspective view of alternative seal assembly for use with the present invention; and 
       FIG. 46  is a top view of the assembly of  FIG. 45  shown in combination with a misaligned slot. 
   

   DETAILED DESCRIPTION 
   A corner connection structure according to the applicant&#39;s teaching is shown generally at  10  in  FIG. 1 . The corner connection structure  10  is provided at a corner  12  where walls  14   a  and  14   b  intersect. The walls  14   a  and  14   b  form part of a building such as, for example, but not limited to, a home or cabin. 
   Referring to  FIG. 2 , the walls  14   a  and  14   b  are constructed of generally horizontally extending logs  16   a  and  16   b , respectively. The walls  14   a  and  14   b  are nonparallel, intersecting each other at the corner  12 . In the embodiment illustrated, the walls  14   a  and  14   b  intersect at approximately 90°. However, the angle of intersection at corner  12  could be any angle, and it is to be appreciated that the corner connection structure  10  could be used on walls having any angle of intersection, and also on walls meeting at a T-intersection. 
   The logs  16   a  and  16   b  of the walls  14   a  and  14   b  have ends  17   a  and  17   b  which are proximate the corner  12 . Adjacent the ends  17   a  and  17   b , the logs  16   a  and  16   b  are provided with overlap portions  18   a  and  18   b , respectively, which overlap each other in an alternating interlaced arrangement at the corner  12 . The logs  16   a ,  16   b  have non-overlapping portions  22   a ,  22   b  adjacent the overlap portions  18   a ,  18   b , respectively. 
   Preferably, the overlap portions  18   a ,  18   b  of the logs  16   a ,  16   b  have a geometrical configuration  20   a ,  20   b , which is shaped so that the overlap portions  18   a ,  18   b  of adjacent logs  16   a ,  16   b  fit together at the corner  12  in an interlocking arrangement. The geometrical configuration  20   a ,  20   b  can include cut-outs as commonly provided in saddle-notch corners, butt-and-pass corners, and in dovetail corner construction. 
   In the embodiment illustrated ( FIGS. 2 and 3 ), the geometrical configurations  20   a ,  20   b , comprise dovetails  21   a ,  21   b  milled into the overlap portions  18   a ,  18   b  of the logs  16   a ,  16   b . Each dovetail  21  has a generally planer upper surface  23  and lower surface  25 , both of which are inclined to the horizontal. Generally vertical shoulder surfaces  27  extend upward and downward from the upper and lower surfaces  23  and  25  of the dovetail  21 , respectively, along the non-overlapping portions  22  of the logs  16 . Each dovetail  21  also has a generally vertical side face  29 , extending between the upper and lower surfaces  23  and  25 . 
   Referring again to  FIG. 2 , the mating surfaces of adjacent dovetails  21  at the corner  12  define corner joint interfaces  24 . More particularly, the upper and lower surfaces  23  and  25  of adjacent dovetails  21  lie generally flush against each other defining generally horizontal (although inclined) corner joint interfaces. As well, the shoulder surfaces  27  lie generally flush against the side faces  29  of the adjacent dovetails  21 , defining generally vertical corner joint interfaces. 
   Referring now to  FIGS. 2 and 4 , the wall  14   a  has a distinct wall section  26   a  in which the non-overlapping portions  22   a  of the logs  16   a  are vertically adjacent each other. Similarly, the wall  14   b  has a distinct wall section  26   b  in which the non-overlapping portions  22   b  of the logs  16   b  are vertically adjacent each other. 
   The area between the distinct wall sections  26   a  and  26   b  of the intersecting walls  14   a  and  14   b  is defined as the corner joint area  28 . The corner joint area  28  is characterized as an area of the intersecting walls  14   a  and  14   b  in which the overlapping portions  18   a  and  18   b  of the logs  16   a  and  16   b  overlap each other in an alternating, interlaced arrangement. 
   Referring to  FIG. 5 , the corner connection structure  10  is further provided with a slot  30  that extends, in the horizontal, obliquely across the corner joint area  28  of the intersecting walls  14   a ,  14   b . The slot  30  extends, in the vertical, along substantially the entire height of the walls  14   a ,  14   b  at the corner  12 . 
   As best seen in  FIG. 6 , vertically aligned grooves  32   a ,  32   b  are provided in the logs  16   a ,  16   b . The grooves  32   a ,  32   b  cooperate to form the slot  30  in the corner connection structure  10 . More specifically, each log  16   a ,  16   b  is provided with a groove  32   a ,  32   b  that extends vertically through the height of the log  16 , and extends horizontally in a direction which is oblique to the longitudinal axis of the log  16 . 
   The particular angle between the grooves  32   a ,  32   b  and the horizontal axis of the corresponding logs  16   a ,  16   b  can conveniently be selected to be generally equal to each other. The slot  30  formed by the cooperating grooves  32   a ,  32   b  is thereby generally perpendicular to a line bisecting the included angle between the intersecting walls  14   a  and  14   b . In the embodiment illustrated, the walls  14   a ,  14   b  intersect at 90°, and the grooves  32   a ,  32   b  are oriented at about 45° relative to the corresponding longitudinal axes of the logs  16   a ,  16   b.    
   Further details of the grooves  32  will now be described, with reference to  FIG. 7 . Each groove  32  in the logs  16  has an open vertical edge  34  positioned along the log  16  to abut the overlap portion  18 . In other words, the log material on either side of the open vertical edge  34  of the groove  32  is part of the overlap portion  18  of the log  16 . The groove  32  extends horizontally to a closed vertical edge  36 , which is positioned within the adjacent non-overlapping portion  22  of the log  16 . 
   In logs  16  having overlap portions  18  with geometrical configurations  20 , the height of the log  16  will generally not be constant along the length of the groove  32 . For example, in the embodiment illustrated having dovetails  21 , the height of the log  16  has a step at the shoulder surface  27 . The intersection of the groove  32  and the shoulder surface  27  defines a threshold  33  within the groove  32 . 
   As best seen in  FIG. 7 , each groove  32  has an interstacking portion  35  which extends within the overlap portion  18  of the log  16 . In the embodiment illustrated, the interstacking portion  35  of the groove  32  extends from the open vertical edge  34  to the threshold  33 . Each groove  32  also has a non-interstacking portion  37  extending within the non-overlap portion  22  of the log  16 . In the embodiment illustrated, the non-interstacking portion  37  of the groove  32  extends from the threshold  33  to the closed vertical edge  36 . 
   The side surfaces of the groove extending between the open edge and the closed edge define an outer side surface  38  facing towards the end  17  of the log  16  proximate the corner  12 , and an inner side surface  40  opposite the outer side surface  38 . 
   As mentioned above, the grooves  32  of vertically adjacent logs  16  at the corner  12  cooperate to form the slot  30 . More specifically, the overlap portions  18   a  of the logs  16   a  of the first wall  14   a  and the overlap portions  18   b  of the logs  16   b  of the second wall  14   b  overlap each other in an alternating, interlaced arrangement at the corner  12  ( FIG. 2 ). The interstacking portions  35   a  and  35   b  of the grooves  32   a  and  32   b  therefore also overlap in an alternating fashion. The grooves  32   a  and  32   b  are positioned in the logs  16   a  and  16   b  of the walls  14   a ,  14   b , so that the outer side surfaces  38   a ,  38   b  of the grooves  32   a ,  32   b  of vertically adjacent logs  16   a ,  16   b  are substantially coplanar, providing a generally continuous outer sidewall  42  of the slot  30  ( FIGS. 5 and 6 ). Similarly, the inner side surfaces  40   a ,  40   b  of the grooves  32   a ,  32   b  of vertically adjacent logs  16   a ,  16   b  are in substantially coplanar alignment, forming a generally continuous inner sidewall  44  of the slot  30 . 
   The non-interstacking portions  37   a ,  37   b  of the grooves  32   a ,  32   b  provided in logs  16   a ,  16   b  do not overlap each other in an alternating, interlaced arrangement. The non-interstacking portions  37   a  are vertically adjacent other non-interstacking portions  37   a , and the non-interstacking portions  37   b  of the grooves  32   b  of logs  16   b  are vertically adjacent other non-interstacking portions  37   b.    
   The open vertical edges  34   a  of the grooves  32   a  in the logs  16   a  generally adjoin the grooves  32   b  where the grooves  32   b  cut through the shoulder surfaces  27   b  of adjacent logs  16   b . In other words, the open vertical edges  34   a  of the grooves  32   a  are vertically aligned with the thresholds  33   b  of the grooves  32   b  in the adjacent logs  16   b . Similarly, the open vertical edges  34   b  of the grooves  32   b  in the logs  16   b  generally adjoin the grooves  32   a  where the grooves  32   a  cut through the shoulder surfaces  27   a  of the adjacent logs  16   a . This alignment of the grooves  32   a  and  32   b  forms the slot  30 , extending between generally continuous vertical edges  36   a  and  36   b , and inner and outer sidewalls  44  and  42 . 
   It is to be appreciated by one skilled in the art that logs used to construct log homes typically do not have a vertically symmetrical cross-sectional profile, but rather, the logs often have distinct upper surface and lower surface profiles. Accordingly, the logs of the first wall  14   a  and the logs of the second wall  14   b  have grooves  32   a ,  32   b  which are mirror image to each other, rather than identical to each other. Further details of log profiles according to the present invention will be discussed subsequently. 
   As seen in  FIG. 2  the corner connection structure  10  is further provided with a spline  50 , which is adapted to fit snugly in the slot  30 . Referring to  FIGS. 8 ,  9   a  and  9   b , the spline  50  has a horizontal width  52  which extends substantially all the way across the width of the slot  30 , between the opposed vertical edges  36   a  and  36   b . The spline  50  has a thickness  54  which is small enough to allow the spline  50  to be inserted in the slot  30 , but is preferably large enough to provide upper and lower horizontal edge surfaces  56  which facilitate stacking of the splines  50  upon one another in the slot  30 . In the embodiment illustrated in  FIG. 9   a , the spline  50  has a plate portion  58  that extends between opposed vertical edges  57  and between upper and lower horizontal edges  56 . The plate portion  58  of the spline  50  has a thickness  54  which is slightly less than the space between the sidewalls  44  and  42  of the slot  30 , and a width  52  which is slightly less than the space between the edges  36   a ,  36   b  of the slot  30 . 
   The height  55  of the spine  50  can be any height which is convenient for the assembly of the corner connection structure  10 . As best seen in  FIG. 4 , the stacked spines  50  extend almost the entire height of the walls  14   a ,  14   b  at the corner  12 . The upper edge  56  of the uppermost spline  50  is spaced below the tops of the walls  14   a ,  14   b  to provide a settling gap  49 . 
   In the embodiment illustrated, a typical spine  50  is shown having a height approximately equal to the height of the logs  16   a ,  16   b  used to construct the walls  14   a ,  14   b . The stacking of the spines  50  produces seams  59  between the upper and lower horizontal edge surfaces  56  of vertically adjacent spline  50 . 
   The height  55  of the splines  50  in the corner connection structure need not be uniform, and the height of some splines  50  can be increased to advantageously reduce the number of splines  50 , and hence the number of seams  59  between adjacent splines  50 , at the corner  12 . Reducing the number seams  59  reduces the number of potential gaps through which drafts and moisture can pass. 
   The splines  50  can be constructed of any suitable material, such as, but not limited to, steel, aluminum, or polymer material. The splines  50  may advantageously be cut to the desired height from a length of extruded material. 
   As each log  16  is laid down at the corner  12 , a spline  50  is inserted into the slot  30 , and pressed snugly against the previously installed spline  50 . This ensures that the grooves  32   a ,  32   b  are properly aligned to extend the slot  30  as successive logs  16  are installed, and also provides stability of the logs  16  as the walls  14   a ,  14   b  are being built. 
   As best seen in  FIG. 10 , the spines  50  simultaneously block off the joint interfaces  24  between the overlap portions  18   a ,  18   b  of the adjacent logs  16   a ,  16   b  of the corner  12 . In particular, the generally horizontal joint interfaces between the upper and lower surfaces  23  and  25  of adjacent dovetails  21 , as well as the generally vertical joint interfaces between the shoulder surfaces  27  and the adjacent side faces  29  of adjacent dovetails  21  are sealed against weather intrusion by the spline  50 . This advantageously eliminates the need for gaskets or caulking between the mating joint interface surfaces  24  at the corner  12 . 
   To further enhance the weather-proofing characteristics of the corner connection structure  10 , the vertical position of the seams  59  between vertically adjacent splines  50  can be adjusted so that the seams  59  intersect with the joint interfaces  24  as few times as possible. In the embodiment illustrated, having geometrical configurations  20  comprising dovetails  21 , the seams  59  are positioned at approximately the vertical midpoint of the dovetail  21  of any single log  16   a  or  16   b.    
   Furthermore, a sealant  60  can be provided between the upper and lower edge surfaces  56  of adjacent splines  50  to enhance the weatherproofing characteristics of the corner connection structure  10 . The sealant  60  can be, for example, but not limited to, a strip of asphalt-impregnated sealant tape. 
   Referring again to  FIGS. 8 ,  9 , and  10 , the spline  50  can be provided with a locking rib  62  having a thickness  64  which extends transversely from the plate portion  58  of the spline  50 . In the embodiment illustrated in  FIG. 8 and 9 , the rib thickness  64  extends from the outer surface of the spline, and the rib is oriented generally vertically along the outer surface of the spline, at about an equal distance from the opposed vertical side edges  57  of the plate portion  58  of the spline  50 . 
   The locking rib  62  enhances the corner connection structure  10  by preventing horizontal movement of the logs relative to one another in a direction parallel to the plate portion  58  of the spline  50 . Furthermore, the rib  62  provides a fixed point towards which the log  16  will draw as it dries and shrinks over time. By providing a single point towards which the logs  16  in the walls  14  will shrink, a tighter, stronger joint is generated over time. 
   To accommodate the rib  62 , the slot  30  is provided with a generally continuous rib recess  66  ( FIG. 5 ). In the embodiment illustrated, the rib recess  66  comprises a generally cylindrical bore  67  positioned adjacent the outer sidewall  42  of the slot  30 . The cylindrical bore  67  has a diameter tangentially intersected by the slot  30 . 
   To form the rib recess  66 , pockets  68   a ,  68   b  are provided along the grooves  32   a ,  32   b  in the logs  16   a ,  16   b  ( FIG. 6 ). The pockets  68   a ,  68   b  overlap in alternating arrangement at corner  12 , and are positioned to be in vertical alignment, thereby forming the rib recess  66 . 
   Referring to  FIG. 8   a , the cross-sectional profile of the outer surface of the rib  62  can be shaped to cooperate with the inner surface of the rib recess  66  so that areas of contact  70  between the rib  62  and the rib recess  66  are interspersed with areas of non-contact  72 . In the embodiment illustrated, the rib  62  has an outer surface which is polygonal having a plurality of vertices  74 , and the inner surface of the rib recess  66  is generally cylindrical. The vertices  74  of the outer surface of the rib  62  are sized to have a slight interference fit with the inner surface of the rib recess  66 . This provides good holding contact, while also reducing the chances of binding in the vertical direction. This is considered advantageous because relative movement between the splines and the logs in the vertical direction is desirable to accommodate natural settling of the logs over time. 
   An alternative spline  80  is illustrated in  FIG. 11 . The spline  80  is similar to the spline  50 , having a plate portion  58  and a rib  62 . However, in the spline  80 , the plate portion  58  is comprised of two distinct plate portion segments  82  and  84 , each of which extends contiguously in opposite directions from the rib  62 . In the embodiment illustrated, a gap  86  separates the plate portion segments  82 ,  84 , and the gap  86  is positioned adjacent the rib  62 . 
   Through-Bolt System 
   The corner connection structure  10  can further be provided with a through-bolt clamping apparatus shown generally at  110  in  FIGS. 1 and 4 . The through-bolt clamping apparatus  110  has a through-bolt  112  that extends generally vertically through the plurality of courses of logs  16  forming the walls  14   a ,  14   b.    
   In the embodiment illustrated in  FIG. 4 , the through-bolt  112  of the through-bolt clamping apparatus  110  extends through the corner joint area  28  of the walls  14   a ,  14   b  at the corner  12 . To accommodate the through-bolt  112 , the spline  50  can be provided with a vertically oriented bolt cavity  114  ( FIG. 12 ). In cross section, the bolt cavity may be enclosed by the spline itself, or by a combination of the spline and a sidewall of the slot. 
   As best seen in  FIG. 13 , in one embodiment the bolt cavity  114  is provided within the rib  62  of the spline  50 . The cross sectional area of the bolt cavity  114  is completely enclosed within the spline  50 . Furthermore, in the embodiment illustrated, the bolt cavity  114  is polygonal in cross section. More specifically, the bolt cavity  114  has an inner surface  116  which is hexagonal in cross-section. 
   Referring again to  FIG. 12 , the through-bolt clamping apparatus  110  is provided with transversely extending upper and lower clamp arms  120 ,  121  (respectively), adjacent the upper and lower ends  118 ,  119  of the through-bolt  112 . The upper and lower clamp arms  120 ,  121  are adapted to couple the through-bolt  112  to the logs  16  at the upper and lower ends of the walls  14   a ,  14   b , respectively. 
   In the embodiment illustrated, the lower clamp arm  121  of the through-bolt clamping apparatus  110  is part of an anchor spline assembly  117  having an anchor plate  122  extending through a horizontal groove  124  provided across the rib  62  of the lowermost spline  50  of the corner connection structure  10 . The anchor plate  122  has a centrally located aperture  126 , which is aligned with the bolt cavity  114  extending through the spline  50 . 
   A fastener  128  extends upward through the aperture  126 , and engages an elongate hex-nut  130  which is provided within the bolt cavity  114 , adjacent the top surface  132  of the anchor plate  122  . The outer surface of the hex-nut  130  is slightly smaller than the hexagonal inner surface  116  of the bolt cavity  114 , thereby permitting axial displacement of the hex-nut  130  within the bolt cavity  114 , but inhibiting rotation of the hex-nut  130  when the threaded rod  112  is turned. Accordingly, an anti-rotate coupling device is provided which enables assembly and adjustment of the threaded rod  112  to the lower clamp arm  121  from the upper end of the walls  14   a ,  14   b , without need to access the through-bolt apparatus  110  from the lower end of the walls  14   a ,  14   b.    
   The fastener  128  passes through the aperture  126  in the anchor plate  122  and is tightened securely, thereby producing the anchor spline assembly  117 . The length of the screw  128  and the length of the hex-nut  130  are selected so that an upper portion of the hex-nut  130  extends sufficiently beyond the upper end of the screw  128 , thereby providing adequate engagement with a threaded portion  134  provided adjacent the lower end  119  of the through-bolt  112 . 
   Referring to  FIG. 14 , a clamp arm recess  136  is provided in the underside of the lowermost (starter) log  16  at the corner  12  of the walls  14   a ,  14   b , to accommodate the transversely extending anchor plate  122 . More specifically, the length and the width of the clamp arm recess  136  are sized slightly larger than the length and the width of the anchor plate  122 . The depth of the recess  136  provides an indented horizontal contact surface  138  for bearing the clamp load applied by the through-bolt clamping apparatus  110  on the anchor plate  122 . 
   Once the intersecting walls  14   a ,  14   b  have been completely assembled, the threaded rod  112  of the through-bolt clamping apparatus  110  can be inserted through the bolt cavity  114  and rotated so that its lower threaded end  119  securely engages the elongate hex-nut  130 . Suitable washers  140  and a spline stacking nut  142  can then be installed and tightened along a threaded portion  143  provided adjacent the upper end  118  of the through-bolt  112 . The spline-stacking nut serves to draw the splines  50  together, so that any seams  59  between vertically adjacent splines  50  are substantially weather-tight. The washers  140  and the spline stacking nut  142  are sized so that collectively their outer diameters are small enough to fit within the rib recess of the corner connection structure, but are large enough to provide a lower surface which positively engages an upper surface  56  of the uppermost spline  50  provided in the corner connections structure  10 . 
   It is considered advantageous to avoid direct application of a clamp load generated by the clamping apparatus  110  onto the corner joint area  28 , because the portions of the logs  16  at the corner joint area  28 , namely the overlap portions  18 , typically shrink more quickly than the adjoining, non-overlap portions  22 . The increased rate of shrinkage can be the result of proximity to the exposed ends  17  of the logs, and because the overlap portions  18 , having geometrical configurations  20 , have a reduced cross-sectional area relative to the adjoining non-overlapping portions  22 . 
   Accordingly, the upper clamp arm  120  comprises a transfer bar  144  coupled to the through-bolt  112  ( FIG. 4 ). The transfer bar  144  is adapted to bridge the non-overlapping portions  26   a ,  26   b  of the first and second walls  14   a ,  14   b  so that a clamping load generated by the through-bolt clamping apparatus  110  can be transferred directly to the non-overlapping portions  26   a ,  26   b  rather than onto the corner joint area  28 . 
   More specifically, the transfer bar  144  has a body  146  and a pair of spaced-apart contact pads  148   a  and  148   b . The first contact pad  148   a  engages the first wall  14   a  at a position spaced away from the corner joint area  28 , along the non-overlapping distinct wall section  26   a  of the wall  14   a . The second contact pad  148   b  engages the second wall  14   b  at a position spaced away from the corner joint area  28 , along the non-overlapping distinct wall section  26   b  of the wall  14   b.    
   Referring again to  FIG. 12 , the contact pads  148   a ,  148   b  of the transfer bar  144  extend generally vertically from the transfer bar body  146 , which extends generally horizontally between the two contact pads. In the embodiment illustrated, the transfer bar  144  comprises a plate having down-turned ends, resulting in an inverted U-shaped member. 
   The transfer bar  144  is provided with an aperture  150 , which is centrally located along the horizontally extending transfer bar body  146 . The threaded portion  143  of the upper end  118  of the through-bolt  112  passes through the aperture  150 , and a clamping nut  152  can be installed adjacent an upper surface  151  of the transfer bar, to apply the compressive load on the walls. 
   Preferably, as shown in the embodiment illustrated, a compression spring  154  may be provided between the clamp nut  152  and the upper surface  151  of the transfer bar  144 . Spring seats  156  can be provided at the upper and lower ends of the compression spring  154 , to ensure that the spring  154  remains generally concentric about the through-bolt  112 . The compression spring  154  can compensate for natural settling of the logs. 
   By spacing apart the contact pads  148   a ,  148   b  on the transfer bar  144 , the downward compressive force on the walls passes through the non-overlapping portions  22   a ,  22   b  of the logs  16   a ,  16   b  rather than along the overlap portions  18   a ,  18   b , which have a reduced cross-sectional area resulting from the geometrical configurations  20  provided therein. The present invention comprehends that the overlap portions  18  of the logs  16  may dry out more quickly, and may therefore shrink faster and to a greater extent than the adjacent non-overlapping portions  22  of the logs. 
   Furthermore, the present invention comprehends that the logs  16  in the walls  14  will settle over time, causing a corresponding decrease in the overall height of the walls  14 . As the uppermost surface of the walls  14  shifts downwards due to settling, the spring  154  forces the transfer bar  144  downwards, thereby maintaining a positive clamping force on the walls  14 . The settling gap  49 , along with the additional clearance provided by downward extension of the contact pads  148  from the transfer bar body  146 , ensures that the transfer bar can be pushed downward without interfering with the uppermost spline  50 . 
   To assist in transferring the clamp load generated by the clamping apparatus  110  away from the corner joint area  28  and onto the adjoining, distinct wall sections  26   a ,  26   b  of the walls  14   a ,  14   b , an alternative anchor spline assembly  157  can be provided ( FIG. 15 ). The anchor spline assembly  157  has a lower clamp arm  121  comprising an inverted transfer bar  144 . 
   More particularly, the anchor spline assembly  157  has a spline  50 , an elongate hex nut  130 , and a transfer bar  144 . The transfer bar  144  is inverted, so that the contact pads  148   a ,  148   b , are directed upwardly. A fastener  160  extends upwardly through the aperture  150  and engages the hex nut  130 . The hex nut is then inserted in the lower end of the bolt cavity  114  extending through the rib  62  of the spline  50 . In the embodiment illustrated, the fastener  160  is a bolt welded to the body  146  of the transfer bar  144 . 
   To accommodate the transfer bar  144  of the anchor spline assembly  157 , a clamp arm recess  162  is provided at the lower end of the corner joint area  28  of the walls  14   a ,  14   b  at the corner  12 . The clamp arm recess  162  crosses the corner joint area  28 , having recess portions  162   a  and  162   b  in the logs  16   a  and  16   b , respectively. Inner sidewalls  164  extend generally vertically along the perimeter of the recess  162 . An assembly retaining screw  168 , passing through an aperture  166 , can be used to hold the anchor spline assembly  157  in position, prior to installation and tightening of the clamping apparatus  110 . 
   In use, the contact pads  148   a ,  148   b  of the transfer bar  144  of the anchor spline assembly  157  engage the walls  14   a ,  14   b  along the distinct wall sections  26   a ,  26   b  respectively. Accordingly, the clamping force applied by the clamping apparatus  110  is directed through the non-overlapping portions  22   a ,  22   b  of the logs  16   a ,  16   b  in the walls  14   a ,  14   b  rather than through the overlap portions  18   a ,  18   b.    
   Furthermore, the mating hex profiles of the bolt cavity  114  and hex nut  130 , along with the retaining screw  168  and inner sidewalls  164  provide an anti-rotate coupling arrangement between the transfer bar  144  and the trough-bolt  112 . 
   Referring now to the  FIG. 17 , the through-bolt apparatus  110  can be provided not only adjacent the corner  12 , but also along the wall  14  between corners  12 . A through-bolt cavity  170  extends through the logs  16  of the wall  14  to accommodate the through-bolt  112 . 
   The through-bolt clamping apparatus  110  can be provided with an anti-rotate anchoring device  172  coupled to the lower end  119  of the through-bolt  112 . In one embodiment ( FIG. 18 ), the anchoring device  172  comprises an anchoring sleeve  174  and the lower clamp arm  121 . The lower clamp arm  121  can be a pin  176  adapted to fit in a generally horizontal bore  178  passing through the anchoring sleeve  174 . The pin  176  is longer than the width of the sleeve  174 , so that ends  177  of the pin  176  extend beyond the outer surface of the sleeve  174 . 
   A generally horizontal locking bore  180  is provided in the lowermost (starter) log  16  of the wall  14 . The locking bore  180  intersects the through-bolt cavity  170  adjacent the bottom of the wall  14 , and is adapted to receive the pin  176 . 
   In use, the sleeve  174  of the anchoring device  172  is inserted into the through-bolt cavity  170  of the lowermost log  16  of the wall  14 . The sleeve  174  is positioned so that the bore  178  of the sleeve  174  is aligned with the locking bore  180  of the log  16 . The pin  176  is then inserted into the locking bore  180  and pushed through the bore  178  of the sleeve  174 . A plug  181  can be inserted into the exposed end of the bore  180  for concealment. 
   The engagement of the ends  177  of the pin  176  with the inner surface of the locking bore  180  of the log  16  provides a bearing surface for the clamp load applied by the clamping apparatus  110 , and also provides an anti-rotate coupling arrangement of the pin  176  to the lower end  119  of the through-bolt  112 . 
   More particularly, the sleeve  174  is provided with an internally threaded vertical engagement bore  182 , having a tapered lead surface  184 . The lower end  119  of the through-bolt  112  can be lowered into the through-bolt cavity  170  from above, and guided into the engagement bore  182  by the tapered lead surface  184 . The through-bolt  112  can then be rotated to securely engage the sleeve  174 . 
   An alternative anchoring device  186  can be used in place of anchoring device  172 . Referring to the  FIGS. 20 and 21 , the alternative anchoring device  186  comprises an inverted transfer bar  144  as its lower clamp arm  121 . The fastener  160  extending from the transfer bar  144  is coupled to a generally vertical internally threaded bore  190  provided in an anchor sleeve  188 . The upper end of the bore  190  of the anchor sleeve  188  is provided with a tapered lead surface  192 , similar to the surface  184  of the sleeve  174 . 
   To accommodate the transfer bar  144 , a clamp arm recess  194  is provided in the underside of the lowermost log  16  of the wall  14 . A retaining fastener  168  can be provided through an aperture  166  in the transfer bar  144  to retain the anchoring device  186  within the recess  194  in the log  16 . The inner sidewalls of the recess  194 , along with the retaining fastener  168 , prevent rotation of the transfer bar  144 , thereby permitting installation and adjustment of the through-bolt  112  from the upper end of the wall  14 , without the need for a second person to hold tight the anchoring device  186 . 
   Log Profile 
   A log profile according to the applicant&#39;s teaching is referenced in the figures generally by character  210 . The log profile  210  may be provided in the log  16  used to construct walls  14  of, for example, but not limited to, a cabin or house. 
   Referring to  FIG. 22 , the profile  210  of the log  16  provides a top surface  212 , a bottom surface  214 , an inner side surface  216 , and an outer side surface  218 . The inner side surface  216  is a generally planer vertical surface, extending between upper and lower inner edges  220 ,  222 , respectively. The outer side surface  218  is similarly a generally planer vertical surface, which extends between upper and lower outer edges  224 ,  226 , respectively. 
   The top surface  212  of the profile  210  extends between the inner and outer upper edges  220  and  224 . The top surface  212  has two vertically upwardly projecting tongues  230 , each having inner and outer inclined sidewalls  232  and  234 , respectively. In the embodiment illustrated, the outer sidewall  234  is double-inclined, having a steeper inclined upper portion  234   a , and a less steeply inclined lower portion  234   b . The tongues  230  have generally horizontal upper faces  236  extending between the inner and outer sidewalls  232 ,  234  of the tongues  230 . 
   The profile  210  further comprises a channel  238  extending between the inner side surfaces  232 ,  232  of the tongues  230 . A v-groove  240  is provided in the channel  238 , extending along the longitudinal axis of the log  16 . 
   The bottom surface  214  of the profile  210  extends between the inner and outer lower edges  222  and  226 . The bottom surface  214  has two upwardly directed engagement grooves  242  adapted to receive the tongues  230  of the top surface  212  of an adjacent log  16 . Each groove  242  has inner and outer inclined sidewalls  244 ,  246 , respectively. In the embodiment illustrated, the outer sidewall  246  is double-inclined, having a more steeply inclined upper portion  246   a , and a less steeply inclined lower portion  246   b . Each groove  242  has a generally horizontal base  248  extending between the inner and outer inclined sidewalls  244  and  246 . 
   A seal recess  250  can be provided in the base  248  of the grooves  242 . In the embodiment illustrated, the seal recess  250  is positioned in the base  248  of each groove  242 , immediately adjacent the outer inclined sidewall  246 . 
   The profile  210  of the log  16  further provides a plateau surface  252  extending between the inner sidewalls  244  of the grooves  242 . A v-groove  254  is provided in the plateau  252 , extending along the longitudinal axis of the log  16 . 
   The bottom surface  214  of the log  16  is also provided with reflexively inclined margin surfaces  256  adjacent the inner and outer side surfaces  216  and  218 . More specifically, one margin surface  256  extends between the lower inner edge  222  of the log  16  and the outer sidewall  246  of the adjacent groove  242 . Similarly, a second margin surface  256  extends between the lower outer edge  226  of the log  16  and the outer sidewall  246  of the adjacent groove  242 . 
   In use ( FIG. 23 ), the top surface  212  and the bottom surface  214  of vertically adjacent logs  16  interlock with each other to provide accurate stacked alignment of the logs in the wall  14 . More particularly, the tongues  230  of the top surface  212  of one log  16  engage the grooves  242  of the bottom surface  214  of another log  16  positioned immediately above the first log. The slopes of the inclined tongue sidewalls  232 ,  234  match the slopes of the corresponding groove sidewalls  244 ,  246  so that they are in flush contact with each other. This contact assists in positively locating the logs relative to each other, and provides lateral stability of the wall  14  in a direction perpendicular to the axes of the logs  16 . 
   Furthermore, the upper faces  236  of the tongues  230  contact the base surfaces  248  of the grooves  242 , to provide positive vertical positioning of one log  16  relative to another. 
   The staggered seam created by the adjacent top and bottom surfaces  212 ,  214  provided by the log profile  210  also assists in keeping out the weather. To further improve the weather proofing characteristics of the interface between the upper surface  212  and the lower surface  214  of adjacent logs  16 , sealant  258  is provided in the seal recess  250  of the bottom surface  214 . The sealant  258  can be, for example, but not limited to, asphalt-impregnated sealant tape. Preferably, the sealant  258  is compressed by the assembly of one log  16  on top of another, to enhance the sealing action of the sealant  258 . 
   The location of the sealant  258  along the interface between the top surface  212  and bottom surface  214  of adjacent logs  16  is also instrumental in blocking out moisture. Specifically, with reference again to  FIG. 23 , the sealant  258  is located along the base  248  of the groove  242  immediately adjacent the interface between the inclined sidewalls  234  and  246  of the tongue  230  and groove  242 , respectively. Accordingly, the sidewall  234  presents an upwards slope towards any moisture attempting to enter the interface between the adjacent logs  16 , from the exposed side surface  218 ,  216 . The force of gravity is thereby used to inhibit the penetration of moisture through the interface. 
   Furthermore, the distal portion of the interface between the logs  16  that extends from the outside face  218  to the seal  258  has no horizontal surfaces. The sloping nature of the interface along that portion of the cross-section of the logs inhibits the collection of water between the logs. 
   Advantages of the double inclined outer sidewalls  234  of the tongue  236  and the margin surface  256  are also best seen in  FIG. 23 . In particular, the double inclined sidewall  234  increases the cross sectional area of material of the log  16  between the tongue  230  and the outside face  218  of the log  16 . This strengthens the lower outer portions of the logs  16 , and resists any lateral outward force exerted by the stacked weight of the logs. As well, the double inclined sidewall  234  and the margin surface  256  provide a blunter point  260  at the bottom of the log  16 , which may be less susceptible to damage during transport and handling of the logs  16 . 
   The interaction of the v-grooves  240  and  254  provided in the top surface  212  and bottom surface  214  of the logs  16  can also best be seen in  FIG. 23 . Specifically, the opposed v-grooves  240  and  254  co-operate to form an aperture  262  between vertically adjacent logs  16  in the wall  14 . The aperture  262  can serve a number of uses, some of which will be discussed hereinafter. 
   Referring now to  FIG. 24 , an alternative profile  270  for the logs  16  has a modified top surface  272  extending between the inner and outer upper edges  220  and  224 , and a modified bottom surface extending between the inner and outer lower edges  232  and  226  of the log  16 . 
   The top surface  272  has a pair of upwardly extending tongues  276 , each having inner and outer inclined sidewalls  278 ,  280 , respectively. Each tongue  276  has a top face  284  extending between the inner and outer sidewalls  278 ,  280 . A step-shaped seal recess  286  is provided in the top face  284  of each tongue  276 , immediately adjacent the outer sidewall  280 . 
   The bottom surface  274  of the log profile  270  has a pair of grooves  288 , each having inner and outer inclined sidewalls  290  and  292 , respectively. Each groove  288  has a base  293  extending between the inner and outer sidewalls  290 ,  292 . 
   In the alternative profile  270 , the slopes of the inclined tongue sidewalls  278 ,  280  do not match the corresponding groove sidewalls  290 ,  292  ( FIG. 25 ). More specifically, in the embodiment illustrated, the outer sidewalls  292  of the grooves  288  are sloped more steeply than the outer sidewalls  280  of the tongues  276 . As well, the inner sidewalls  278  of the tongues  276  are sloped more steeply than the inner sidewalls  290  of the grooves  288 . 
   Accordingly, when one log  16  is placed on top of another log  16  in the wall  14 , the tongues  276  of the top surface  272  engage the grooves  288  of the bottom surface  274  of the adjacent log  16 . However, the sidewalls  278 ,  280  of the tongues  276  are not in flush contact with the sidewalls  290 ,  292  of the grooves. Rather, cavities  294  are provided between the sidewalls  280  and  292 . Similarly, cavities  296  are provided between the sidewalls  278  and  290 . 
   The cavities  294  cooperate with the seal recess  286  to accommodate the sealant  258 . The cavities  296  can accommodate additional sealant  258  to further enhance the weather-proofing characteristics of the log interface and to provide lateral stability for alignment of the logs. When the top surface  272  and the bottom surface  274  of two adjacent logs  16  engage each other, the sealant  258  in the cavities  294  and  296  is compressed and squeezed downward within the cavities  294 ,  296  into wedge-shaped seal elements. This fills a portion of the space between the opposed vertically inclined sidewalls, thereby locating the corresponding logs in horizontal alignment with each other. Moreover, the vertically adjacent logs can shrink and expand independently without compromising the weather-proofing characteristics of the sealed interface, since the resilient sealant  258  can expand and contract to accommodate any difference in the rates of expansion or contraction of the logs  16 . In addition, the sealant  258  is positioned away from the center of the log where apertures for plumbing, electrical wiring, or through-bolts are typically provided. Accordingly, the sealant  258  in the embodiment illustrated can extend without interruption along the length of the walls  14 , and problems related to squeeze-out of sealant entering such apertures are eliminated. 
   Wall Support Structure 
   A support structure according to one example of the applicant&#39;s teaching is shown generally in the Figures at reference character  310 . Referring to  FIG. 1 , the support structure  310  is provided adjacent an opening  312  in the wall  14 . The opening  312  may be provided in the wall  14  for a variety of reasons, such as, for example, but not limited to, accommodating a window, door, or fireplace. 
   Referring now to  FIG. 26 , the opening  312  extends between vertical side surfaces  314  and upper and lower horizontal surfaces  316   a ,  316   b , respectively, extending along the logs  16  forming the wall  14 . The vertical side surfaces  314  are also referred to herein as edge surfaces  314  of the wall  14 . The upper and lower horizontal surfaces  316   a ,  316   b  are also referred to herein as header and sill surfaces  316   a ,  316   b , respectively. In milled log packages, the vertical side surfaces  314  of the opening  312  may be precut, providing end faces  318  along either side surface  314  of the opening  312 . Typically, these precut end faces  318  are only provided for logs whose full cross sectional height abuts the sides  314  of the opening  312 . If the height of the opening  312  must be extended partially across the height of adjacent logs, the builder can make vertical extension cuts  320  in logs which run adjacent the upper or lower sides  316  of the opening  312 . In such cases the log material extending between the extension cuts  320  of opposing side surfaces  314  must also be removed, thereby producing the horizontal surfaces  316  of the opening  312 . 
   Referring now to  FIG. 27 , in openings  312  having a full cross-sectional log  16  extending along the lower horizontal surface  316 , support blocks  322 ,  324  can be provided along the top surface  212  of the log  16  having a profile  210 , to square off the lower surface  316  of the opening  312 . In particular, and with reference to  FIG. 28   a , the support blocks  322  each have an inclined base  326  in flush contact with the inclined sidewalls  234  of the tongues  230 . A generally horizontal support surface  328  is provided opposite the base  326 . Referring to  FIG. 28   b , the support block  324  is generally rectangular in cross-section, having a base  330  in flush contact with the channel  238  between the tongues  230  of the log  16  having the profile  210 . A generally horizontal support surface  332  is provided opposite the base  330  of the support block  324 . 
   Referring to  FIGS. 26 and 29 , the support structure  310  comprises connectors  336  positioned within the wall  14  adjacent the opening  312 . The connectors  336  have a connector body with lower and upper log engagement portions  338 ,  340 . In the embodiment illustrated, the connectors  336  comprise dowel pins which are vertically oriented in the wall  14 . The lower engagement portion  338  engages a log in one course of the wall, and the upper engagement portion  340  engages the log immediately above the log engaged by the lower log engagement portion  338 . 
   The number of connectors  336  provided along each vertical side  314  of the opening  312  is such that each log  16  having a fully exposed end face  318 , has a connector  336  extending from both the upper and lower surfaces of the log ( FIG. 26 ). Accordingly, the lowermost logs having end faces  318  adjacent the opening  312  are connected to the log below, which spans the opening  312 . Similarly, the uppermost logs  16  having end faces  318  adjacent the opening  312  are connected to the log above, which spans the openings  312 . The connectors  336  thereby serve to strengthen the wall  14  at the opening  312 , and to align and support the logs as the wall is being built. 
   As best seen in  FIG. 30 , the logs  16  are provided with upper and lower connector apertures  342 ,  344 , respectively, adapted to receive the lower and upper log engagement portions  338 ,  340  of the connectors  336 . The upper and lower connector apertures  342 ,  344  extend into the top and bottom surfaces  212 ,  214  of adjacent logs  16 , and can comprise upper and lower portions of apertures  346  extending through the height of the logs  16  adjacent the opening  312  in the wall  14 . 
   The apertures  342 ,  344  are generally centrally located across the cross-sectional width of the logs  16 . More specifically, the apertures  342 ,  344  intersect the v-grooves  240 ,  254  provided in the top and bottom surfaces  212 ,  214  of the logs  16 . Along the length of the logs  16 , the apertures  342 ,  344  are spaced away from the end faces  318  of the logs  16 , so that an axial load bearing portion  348  of the log  16  is provided between the apertures  342 ,  344  and the end faces  318  ( FIG. 31 ). 
   Referring now to  FIG. 31 , the cross-sectional profile of the outer surface of the connector  336  can be shaped to cooperate with the inner surface of the apertures  342 ,  344  so that areas of contact  350  between the connector  336  and the apertures  342 ,  344  are interspersed with areas of non-contact  352 . In the embodiment illustrated, the connector body is hexagonal and the apertures  342 ,  344  are cylindrical. The vertices of the outer surface of the connector  336  are sized to have a slight interference fit with the apertures  342 ,  344 . This provides good holding contact, while also accommodating some degree of misalignment between the apertures  342 ,  344  provided in vertically adjacent logs  16 . 
   Referring again to  FIG. 26 , the opening support structure  310  further comprises a sub-jamb member (or framing member)  360  having respective upper and lower ends  360   a  and  360   b , and positioned along each vertical side surface  314  of the opening  312 . The sub-jamb members  360  do not extend the full height of the opening  312 , but rather, a settling gap  362  is provided between the upper horizontal surface  316  (i.e. the header surface  316   a ) of the opening  312  and the upper end  360   a  of the sub-jamb members  360 . Typically, this gap would be about 1.5 inches, to accommodate natural settling of the logs over time. 
   As best seen in  FIG. 32 , each sub-jamb  360  has inner and outer vertical struts  364 ,  366  aligned with the inner and outer faces  216 ,  218  (respectively) of the logs  16 . Each strut  364 ,  366  is provided with a vertical groove  368 , the openings of which face each other in horizontal and vertical alignment. The grooves  368  cooperate to receive a central panel  370 . The struts  364 ,  366  are also provided with vertically extending seal recesses  372  along the surface of the struts  364 ,  366  which lie adjacent the vertical side surfaces  314  of the opening  312 . Vertically elongate slots  374  are provided in the central panel  370  of the sub-jamb  360 . 
   To install the sub-jamb member  360  of the opening support structure  310 , fasteners  376  are provided. The fasteners  376  couple the sub-jamb member  360  to the connectors  336 . 
   More specifically, with reference again to a preferred embodiment illustrated in  FIG. 29 , the fasteners  376  can comprise bolts having an external threaded portion  378  at one end, and a bolt head  379  at the opposite end. The bolts  376  extend through the slots  374  of the sub-jamb member  360 , with the threaded portion  378  directed into the vertical side surface  314  of the opening  312 . Washers  380  can be inserted between the sub-jamb  360  and the heads  379  of the bolts  376 . 
   Fastener access passageways  382  are provided in the logs  16  to accommodate the bolts  376 . The fastener access passageways  382  extend between the connectors  336  and the vertical side surfaces  314  of the opening  312 . In the embodiment illustrated, the aperture  262  created by the opposed v-grooves  240 ,  254  in the logs  16  provides the fastener access passageways  382 . 
   The connectors  336  are provided with fastener coupling means  384 , for coupling the fasteners  376  to the connectors  336 . In the embodiment illustrated, the fastener coupling means  384  comprises an internally threaded bore  385  extending horizontally through the connector body, at a position between the first and second log engagement portions  338 ,  340 . The internally threaded bore  385  is adapted to engage the threaded portion  378  of the bolt  376 . 
   The connectors  336  can be further provided with an alignment pin  386  extending generally horizontally beyond the body of the connector  336 . The alignment pin  386  can engage an alignment surface  388  on an adjacent log, to assist in aligning the fastener coupling means  384  with the fastener access passageway  382 . In the embodiment illustrated, the alignment pin  386  is positioned below and in parallel alignment with the internally threaded bore  385 . The converging portion of the v-groove  240  provided in the upper surface  212  of the logs  16  provides the alignment surface  388 . 
   Having aligned the internally threaded bores  385  with the fastener access passageways  382 , the threaded portions  378  of the bolts  376  can engage the internally threaded bores  385  upon insertion through the passageways  382 . The bolts  376  can then be tightened to draw the sub-jamb  360  snugly against the vertical side surfaces  314  of the opening  312 . 
   Upon initial installation, prior to any settling, the relative position of the bolts  376  along the length of the slots  374  is such that a space  390  is provided between the lower edge  392  of the slot  374  and the bolt  376  ( FIG. 34 ). The space  390 , along with the settling gap  362  ( FIG. 26 ), accommodate a reduction in the height of the opening  312  which naturally occurs as the logs  16  settle over time. In particular, the bolts can shift downwards within the slots  374 , towards the lower edges  392  of the slots  374 . Similarly, the upper horizontal surface  316  of the opening  312  can shift downwards towards the upper edges of the sub-jamb members  360 . 
   This ability to accommodate settling of the logs  16  reduces or eliminates the high stress loads which would otherwise be transmitted onto the sub-jamb members  360  as the logs  16  settled over time. Accordingly, the sub-jamb members  360  provide attachment surfaces to which structural elements of a window or door can be fastened, without risk of distortion or damage to the window or door. 
   Furthermore, by coupling the sub-jamb members  360  to the connectors  336 , reliable mounting of the sub-jamb members  360  is realized. In particular, the retaining force that holds the sub-jamb members  360  in place is applied across the load-bearing portion  348  of the logs  16  ( FIG. 31 ). This is in contrast to simply embedding a fastener in the end grain of the logs  16  through the exposed end faces  318 . Fasteners embedded in log end grain are susceptible to loosening as the fibers of the wood can easily spread apart. 
   Exterior Side Casing Structure 
   An exterior side casing structure according to an example of the applicant&#39;s teaching is shown generally in  FIG. 1  at reference character  410 . The side casing structure  410  is provided on the outside of the wall  14  around the perimeter of the opening  312 . 
   Referring to  FIG. 34 , the casing structure  410  comprises vertical casing members  412  extending along the outer side surfaces  218  of the logs  16 , at a position adjacent a framing member such as the sub-jamb members  360  of the opening support structure  310 . 
   Referring to  FIG. 35 , the vertical casing members  412  can be generally rectangular in cross-section, having a front face  414 , a rear face  416 , and inner and outer side surfaces  418  and  420 , respectively. The rear face  416  has a mounting surface  422  adjacent the inner side surface  418 . A channel  424  is provided in the rear face  416  adjacent the outer side surface  420 . 
   Between the channel  424  and the mounting surface  422  of the rear face  416 , a seal recess  426  is provided. A sealant  428  ( FIG. 36 ) can be provided in the seal recess  426 . The sealant  428  can be, for example, but not limited to, asphalt-impregnated sealant tape. 
   Referring to  FIG. 36 , the vertical casing members  412  are mounted adjacent the opening  312  by securing the mounting surface  422  of the rear face  416  to the sub-jamb member  360 . In particular, the mounting surface  422  of casing member  412  is seated against an outside edge surface  367  of the sub-jamb member  360 . Suitable adhesive or fasteners can be used to attach the casing member  412  to the sub-jamb  360 . In the embodiment illustrated, finishing nails  430  are used to attach the casing member  412  to the sub-jamb  360 . 
   As best seen in  FIG. 36 , the channel  424  spans the seams  432  between the sub-jamb  360  and the end faces  318 ,  320  of the logs  16  adjacent the opening  312 . This provides drainage and ventilation for any moisture which may penetrate the area behind the casing members  412  and the seams  432 . 
   To enhance the drainage of any moisture behind the casing members  412 , drainage troughs  434  can be provided in the lower horizontal surface  316  of the opening  312 , directly below the seams  432  and adjacent the channel  424  of the casing member  412 . In the embodiment illustrated, the drainage troughs  434  comprise grooves having an inclined base  436 , an open upper edge  438  facing the lower end of the sub-jamb  360 , and an open front edge  440  facing the channel  424  of the casing member  412 . 
   Butt Joint Connection Structure 
   A butt joint connection structure according to an example of the applicant&#39;s teaching is shown generally in  FIG. 1  at reference character  510 . The butt joint connection structure  510  is provided between adjacent end faces of any two logs  16  comprising the walls  14  so that the logs  16  may be joined together end-to-end. 
   Referring now to  FIG. 37 , the butt joint connection structure  510  is illustrated in combination with two logs  512  and  514  of the logs  16  forming the wall  14 . The logs  512 ,  514  have end faces  516 ,  518 , respectively, (not shown), which are in flush contact with each other forming a seam  520  between the logs  512 ,  514 . 
   The butt joint connection structure  510  comprises a butt spline  522  and fasteners  524 . The butt spline  522  is adapted to be received in a generally vertical spline slot  526  which spans the seam  520  between the adjacent end faces  516 ,  518  of the logs  512 ,  514 . In the embodiment illustrated, the butt spline slot  526  extends horizontally in a direction which is substantially parallel to the common longitudinal axes of the logs  512 ,  514 . 
   To form the butt spline slot  526 , spline grooves  528 ,  530  are provided in the end faces  516 ,  518  of the logs  512 ,  514 , respectively ( FIG. 38 ). Each butt spline groove  528 ,  530  has an open vertical edge  532  provided in the end face  516 ,  518  and an opposed closed vertical edge  534  opposite the open vertical edge  532 . Opposed butt spline groove inner and outer side faces  536 ,  538  extend between the open and closed vertical edges  532 ,  534 . 
   The butt spline grooves  528  and  530  in the logs  512  and  514  are positioned so that the open vertical edges  532  align to face each other. The inner side faces  536  of the grooves  528  and  530  cooperate to form a generally continuous inner sidewall  540  of the butt spline slot  526 . Similarly, the outer side faces of the grooves  528  and  530  cooperate to form a generally continuous outer sidewall  542  of the butt spline slot  526  ( FIG. 37 ). 
   Referring now to  FIG. 39 , the butt spline  522  is generally rectangular in cross-section, being adapted to fit snugly in the butt spline slot  526 . The butt spline  522  has a thickness  546  which fits between the opposed inner and outer sidewalls  540 ,  542  of the slot  526 , and a width  548  which fits between the opposed closed vertical edges  534  of the slot  526 . The butt spline  522  has an inner face  550  in flush contact with the inner sidewall  540  of the slot  526 , and an opposed outer face  552  in flush contact with the outer sidewall  542  of the slot  526 . The height of the butt spline  522  extends substantially along the cross-sectional height of the logs  512 ,  514 . The butt spline  522  can be constructed of wood, polymer, or any other suitable material. 
   The butt spline  522  is provided with vertically extending fastener recesses  554  that are adapted to cooperate with the fasteners  524  for securing the butt joint connection structure  510 . In the embodiment illustrated, two recesses  554  are provided along the inner face  550  of the spline  522 . The recesses  554  are generally semi-circular in cross-section, providing a recess opening  556  in the plane of the inner face  550  of the spline  522 . Furthermore, lateral catch surfaces  558  are provided along the inner surface of the recesses  554 , extending inwardly from either edge of the recess openings  556 . The catch surfaces  558  of the recesses  554  interact with the fasteners  524  to secure the butt joint connection structure  510 , as will be described subsequently. 
   The two recesses  554  are spaced apart so that one recess is on either side of the seam  520  between the logs  512 ,  514 . In other words, the recess opening  556  of one recess  554  abuts the inner side face  536  of the groove  528  provided in the log  512 . The recess opening  556  of the second recess  554  abuts the inner side face  536  of the groove  530  provided in the log  514 . 
   The interaction of the fasteners  524  and the recesses  554  will now be described. Referring to  FIG. 40 , the recesses  554  and the inner faces  536  of the grooves  528 ,  530  cooperate to provide apertures  560  for receiving the fasteners  524 . The apertures  560  provide a cross-sectional area which is significantly less than the cross-sectional area of the fasteners  524 . More particularly, in the embodiment illustrated, the fasteners  524  comprise spikes having a shaft  562  of generally circular cross-section ( FIG. 37 ). The radius of the semi-circular recesses  554  is about equal to the radius of the circular shaft  562  of the spikes  524 . Accordingly, the cross-sectional area of the apertures  560  is only about half that of the cross-sectional area of the shaft  562  of the spikes  524 . 
   As a result, the spikes  524  must be forced into the semi-circular apertures  560  for assembly of the butt joint connection structure  510 . This generates a significant lateral force, pressing the outer face  552  of the spline  522  against the outer side faces  538  of the grooves  528 ,  530 . This force impedes any relative movement between the spline  522  and the logs  512 ,  514 , thereby securing the butt joint connection structure  510 . 
   Furthermore, forcing the spikes  524  into the apertures  560  can create depressions  564  (shown in phantom in  FIG. 40 ) in the logs  512 ,  514 , opposite the recesses  554  provided in the spline  522 . The depressions  564  have log catch surfaces  566  which extend into the inner side faces  536  of the grooves  528 ,  530 . By forming the depressions  564  upon insertion of the spikes  524  into the apertures  560 , the log catch surfaces  566  are necessarily aligned with the opposing spline catch surfaces  558  of the recesses  554 . 
   Accordingly, the shaft  562  of the spikes  524  engages the catch surfaces  558  and  566  formed along the inner surfaces of the apertures  560 , and thereby prevent any horizontal movement of the spline  522  relative to the logs  512 ,  514 . In other words, by extending transversely across the interface between the spline  522  and the grooves  528 ,  530 , and by engaging the respective transverse catch surfaces  558 ,  566 , the shaft  562  of the spikes  524  locks the logs  512  and  514  together. 
   Referring again to  FIG. 37 , the butt joint connection structure  510  can further comprise seal assemblies  570 . The seal assemblies  570  are adapted to be received in seal slots  572 , which span the seam  520  between the adjacent end faces  516 ,  518 , of the logs  512 ,  514 . 
   In the embodiment illustrated, two seal slots  572  are provided in the butt joint connection structure  510 . More specifically, one seal slot  572  is provided between the spline slot  526  and the inner side surface  216  of the logs  512 ,  514 , and another seal slot  572  is provided between the spline slot  526  and the outer side surface  218  of the logs  512 ,  514 . The seal slots extend vertically along the cross-sectional height of the logs  512 ,  514 , and extend horizontally in a direction generally parallel to the common axis of the logs  512 ,  514 . 
   Referring again to  FIG. 38 , each seal slot  572  is formed of opposed seal grooves  574  and  576  provided along the end faces  516  and  518  of the logs  512 ,  514  respectively. Each seal groove has an end wall  578  and opposed side surfaces  580  and  582  extending between the end wall  578  and the end face  516 ,  518 . The side surfaces  580 ,  582  of the grooves  574  are in alignment with the side surfaces  580 ,  582  of the grooves  576 , thereby forming the generally continuous seal slots  572  extending between the end walls  578 . 
   Referring again to  FIG. 37 , the seal assemblies  570  comprise stiffening bars  584  which are affixed to a sealing element  586 . The sealing element is preferably compressible, and may be, for example, but not limited to, asphalt-impregnated sealant tape. The stiffening bars can be of generally rectangular cross-section, and may be constructed of, for example, but not limited to, wood or plastic. 
   In the embodiment illustrated, the seal assemblies  570  comprise two stiffening bars  584  provided on opposite sides of the sealing element  586 . Each stiffening bar  584  has an inner face  588  adjacent the sealing element  586 , and an outer face  590  in contact with an end wall  578  of the seal slot  572 . The stiffening bars  584  and the sealing element  586  have a height which is generally equal to the cross-sectional height of the logs  512 ,  514 . 
   In the relaxed, unassembled state, the seal assemblies  570  have a thickness which fits snugly within the distance between the opposed side surfaces  580  and  582  of the seal slots  572 , and the seal assemblies have a width which exceeds the distance between the opposed end walls  578  of the seal slots  572 . Accordingly, to insert the seal assembly into the seal slot  572 , the two stiffening bars  584  must be pressed together, thereby compressing the sealing element  586 . The seal assembly may then be pressed into the seal slot  572 , by applying force on the upper ends of the stiffening bars  584 . The stiffening bars facilitate proper placement of the sealing element  586  along the height of the logs  512 ,  514 , by preventing the sealing element  586  from folding or crumpling upon insertion into the seal slots  572 . 
   As best seen in  FIGS. 37 and 41 , the butt joint connection structure  510  can be provided with horizontal seals  592  and  594 , to further enhance the weather-proofing characteristics of the butt joint  510 . The seals  592 ,  594  can be, for example, but not limited to, asphalt-impregnated tape. 
   The seals  592  are provided adjacent the upper and lower edges of the butt spline  522 . Accordingly, as best seen in  FIG. 41 , the upper and lower seals  592  are compressed between the upper end of the spline  522  and the plateau surface  252  of the log above the spline  522 , and the lower end of the spline  522  and the channel surface  238  of the log below the spline  522 . 
   The seals  594  are provided adjacent the upper ends of the seal assemblies  570 . The horizontal position of the seal assemblies  570  along the cross sectional width of the logs  16  can be advantageously aligned with the sealant  258  provided in the recesses  250  in the logs  16  ( FIG. 41 ). Accordingly, the seals  594  are compressed between the upper ends of the seal assemblies  570  and the adjacent sealant  258 . The lower end of each seal assembly  570  bears directly against the adjacent sealant  258 . Additional seals  594  could be provided between the lower ends of the seal assemblies  570  and the adjacent sealant  258 . 
   As seen in  FIG. 41 , the apertures  262  advantageously provide clearance between vertically adjacent logs to accommodate the head of the fastener  524 . 
   Post-to-Log Connection Structure 
   A connection structure according to an example of the applicant&#39;s teaching is shown generally at  610  in  FIG. 42 . The connection structure  610  has a generally vertical post  612  to which horizontal logs  16  of a wall  14  can be attached. The use of vertical posts  612  can provide a method of connecting intersecting walls  14 , and can provide support points along a wall  14  and can advantageously reduce the required length of the logs  16 . 
   The post  612  has a generally vertical joint face  614  which is shaped to engage end faces  616  of the logs  16  in substantially flush contact. In the embodiment illustrated, the joint face  614  and end faces  616  are planar surfaces oriented generally vertically (the end faces  616  defining an edge surface of wall  14 ), but other configurations could also be provided. Furthermore, in the embodiment illustrated, the vertical post  612  is generally square in cross-section, and a single joint face  614  for connection to logs  16  has been illustrated. The post  612  could have any one of a variety of cross-sectional profiles, including, for example, but not limited to, hexagonal or octagonal. The post  612  would generally be provided with at least two joint faces  614 . 
   The connection structure  610  further comprises a link assembly  620  for coupling the logs  16  to the post  612 . The link assembly  620  comprises a post-engaging clamp bracket  622 , a log-engaging connector  624 , and a fastener  626  extending between the bracket  622  and connector  624 . 
   As best seen in  FIG. 43 , in the embodiment illustrated, the fastener  626  is a socket head cap screw. An elongate hex nut  628  is threaded onto the end of the fastener  626 . A lock pin  630  is provided transversely through a distal end of the nut  628 , for purposes which will be described hereinafter. The lock pin  630  can be press fit into a corresponding bore  629  provided through the nut  628 . 
   The clamp bracket  622  has lateral clamp arm ends  631  which extend beyond the profile of the hex nut  628 . In the embodiment illustrated, the clamp arm ends  631  comprise horizontally outer portions of a pair of flanges  632   a ,  632   b , which are connected along a leading edge  634  to form a v-shaped profile. In the link assembly  620 , the leading edge  634  of the bracket  622  is directed towards the connector  624 . The bracket  622  has an aperture  636  which is generally centrally located, and intersects the leading edge  634 . The aperture  636  is sized to allow passage and rotation of the hex nut  628  within the aperture  636 . 
   The connector  624  has upper and lower log engagement portions  638 ,  640 , respectively, which are adapted to engage vertically adjacent logs  16  in the wall  14 . In the embodiment illustrated, the connector  624  is a vertically oriented dowel pin of hexagonal cross-sectional profile. The connector  624  also has a horizontal bore  642  positioned between the upper and lower log engagement portions  638 ,  640 , which is adapted to receive the fastener  626 . More specifically, the bore  642  is sized to permit sliding passage of the shaft of the fastener  626 , and is counter-bored opposite the bracket  622  to provide a recessed fit for the head of the fastener  626  ( FIG. 42 ). 
   The post  612  is provided with a channel  646  extending along the joint face  614 . The channel  646  has a bracket housing portion  648  shaped to receive the bracket  622 , and a slot portion  650  extending between the bracket housing portion  648  and the joint face  614 . The bracket housing portion  648  is provided with oblique retaining shoulders  652   a ,  652   b  which are shaped and positioned to engage the flanges  632   a ,  632   b  of the bracket  622 . More specifically, the retaining shoulders  652   a ,  652   b  in the embodiment illustrated extend outwardly from either side of the slot portion  650  of the channel  646 , and away from the joint face  614  ( FIG. 44 ). 
   The logs  16  are provided with upper and lower connector apertures  662 ,  664 , which are the same as the connector apertures  342 ,  344 , provided in the opening support structure  310  of the present invention. The upper and lower connector apertures  662 ,  664  in vertically adjacent logs  16  are shaped to receive the lower and upper log engagement portions  640 ,  638 , respectively, of the connector  624 . 
   In use, the post  612  is positioned adjacent a log  16 , so that the joint face  614  of the post  612  is in flush contact with the end face  616  of the log  16 . 
   The bracket  622  of the link assembly  620  can then be aligned with, and slidingly inserted into, the bracket housing portion  648  of the channel  646  in the post  612 . The link assembly  620  is lowered to a point where the connector  624  contacts the log  16 . The connector  624  can then be aligned with the aperture  662  by orienting the connector  624  to the vertical and adjusting the fastener  626  as may be required to obtain the correct spacing between the bracket  622  and the connector  624 . During the alignment process, the lock pin  630  passing through the nut  628  can be advantageously seated within the converging flanges  632   a ,  632   b  to provide an anti-rotate coupling arrangement of the nut  628  and the fastener  626 . 
   Once aligned, the connector  624  can be tapped or pressed into place, so that the lower log engagement portion  640  of the connector  624  engages the upper connector aperture  662  in the log  16 . The lowermost installed position of the connector  624  is achieved when the shank of the fastener  626  bottoms out in the v-groove  240  provided along the top surface of the log  16 . 
   Once the connector  624  has been installed, the fastener  626  can be tightened to draw the post  612  and the log  16  snugly together. In particular, with reference to  FIG. 44 , tightening the fastener  626  draws the clamp bracket  622  towards the connector  624 . Accordingly, the flanges  632   a ,  632   b  of the bracket  622  bear against the retaining shoulders  652   a ,  652   b , of the channel  646 . This provides a reliable connection and also serves to horizontally align the log  16  and the post  612 , due to the oblique angle at which the retaining shoulders  652  and flanges  632  are provided. 
   After tightening the fastener  626 , the next log  16  may be laid down, ensuring that the lower connector aperture  664  in the lower surface of the next log is aligned with and engages the upper log engagement portion  638  of the connector  624 . 
   Accordingly, the connection structure  610  provides a secure joint which stabilizes the logs horizontally in a direction perpendicular to the axis of the logs  16 , but also draws the logs  16  snugly against the post  612 . Moreover, the bracket  622  can shift in a vertical direction relative to the post  612 , allowing the post-to-log connection structure  610  to accommodate natural settling of the logs  16  relative to the post  612  over time. 
   The connection structure  610  can further be provided with a seal assembly  570 , as provided in the butt joint connection structure  510 . In the embodiment illustrated, two seal slots  672  are provided, each seal slot  672  being shaped to receive a seal assembly  570 . 
   Each seal slot  672  spans the seam between the joint face  614  of the post  612 , and the end face  616  of the log  16 . The seal slots  672  are similar to the seal slots  572 , being formed of opposed seal grooves  674  and  676  provided along the joint face  614  of the post  612  and the end face  616  of the log  16 , respectively. As for the butt joint connection structure  510 , the seal assemblies  570  may be inserted into seal slots  672  of the post-to-log connection structure  610  by pressing the stiffening bars  584  together, so that the sealing element  586  is compressed. The seal assembly  570  may then be inserted into the slot  672  by applying a downward force to the upper ends of the stiffener bars  584 . 
   Referring to  FIG. 45 , an alternative seal assembly  670  is illustrated. The seal assembly  670  may be used as an alternative to the seal assembly  570  in either of the butt joint connection structure  510  or post-to-log connection structure  610  of the present invention. 
   The seal assembly  670  is provided with a pair of opposed stiffener bars  684 , but rather than having a single sealing element  586  extending between the bars  684 , two separate sealing elements  686   a  and  686   b  are provided. Each of the sealing elements  686   a ,  686   b  are affixed to only one stiffener bar  684 . Accordingly, the seal assembly  670  comprises two seal sub-assemblies  670   a  and  670   b.    
   The seal assembly  670  can advantageously be used in cases where the grooves  574  and  576 , or  674  and  676 , are not in precise alignment with each other ( FIG. 46 ). The slots  572 ,  672  so formed can have an offset along the seams which they span. Accordingly, one seal sub-assembly  670   a ,  670   b  can be squeezed into each groove  574 ,  674  or  576 ,  676  such that the sealing portions  686   a ,  686   b  abut each other at the seam, and improved weather-proofing can thereby be provided. 
   While preferred embodiments of the invention have been described herein in detail, it is to be understood that this description is by way of example only, and is not intended to be limiting. The full scope of the invention is to be determined from reference to the appended claims.