IE43041B1 - A wooden building having the appearance of a log cabin with corner joints formed by crossed interlocking log - Google Patents

Abstract

1508266 Joints in mock log cabins ARCA HOLDING SA 11 Aug 1976 [14 Aug 1975] 33487/76 Heading E1W [Also in Division F2] A mock log cabin has corner joints comprising short log members 8 formed with upper and lower oppositely directed rebates in which the members 8 are engaged in alternating superadjacent crossed - over configuration. The corner has outwardly directed @save ends 9 and inwardly directed stubs. Horizontally extending boards 7 are provided with end tenons 14 which are engaged in cavities formed by outwardly directed lateral rebates in the log members and which are clamped in place by adjacent log members. An inner skin of plasterboard 2 may be fixed to noggins 3 and glass or mineral fibre mats or foamed in situ plastics incorporated between the skins 1, 2. A further skin 5 may be sprung between the noggins to provide an air gap behind the boards 8 for ventilation. Bolts in bolt holes 17 are tightened after drying of the timber. The boards 7 and logs 8 may be prefabricated as a single unit by glueing.

Description

PAIINT APPLICATION BY (71) ARCA HOLDING S.A. A COMPANY INCORPORATED UNDER LUXEMBOURG LAW, OF 2, BOULEVARD ROYAL, LUXEMBOURG.

Prtct 12ip Ο 4 4 The invention relates to a wooden building having the appearance of a log cabin with corner joints formed by crossed-over interlocking logs, and in which.building the corner joints are formed by short log members which are rebated and are mounted in alternate superjacent crossed-over configuration, have outwardly pointing stave ends and respective oppositely directed stubs to which the walls of the. building, formed by horizontally extending boards, are attached.

The demand for log cabins, more particularly vacation buildings, has substantially increased in recent times. Genuine log cabins, however, call for skill in their production and require a large quantity of timber. They are therefore particularly expensive. Moreover, they suffer from numerous disadvantages, inter alia distortion due to drying, leakages and the like.

To reduce the timber consumption and to achieve better insulation as compared with genuine log cabins, while preserving, in a building, the appearance of a log cabin,, it is already known to form the building corners from stacks of short log members which are alternately inter-leaved in a cross-over pattern and are screwed together have stave ends which point outwardly and. which log members are provided on the interior with rebated stems or stubs on which an external wall as well as an internal wall is mounted. In a known construction disclosed in German patent specification 186,837, the log members are first stacked one upon the other and screwed to each other to form corner posts. The boarding for forming the external wall is then mounted from the interior. The boards for the internal wall however, are mounted on separate nogging strips which are affixed to the log members, an insulating space ±’emaining between the external and internal wall. The disadvantage of this embodiment however is that the outer boarding abuts behind the stave ends of the log members and must therefore have a smooth external surface, at least at the ends. The character of a log cabin will however thus be lost. Contact and mounting of the double-skinned frame partition wall which bears on the stacked log members is not very durable. In another embodiment described in the Swiss patent specification 433,67% the intersecting log members are provided with extended rearward gusset stubs on which a doubleskinned frame partition wall is mounted. The ends of the outer wall boarding engage in dovetail configuration in grooves situated outside the joint in the transversely disposed log members. However, it is a disadvantage that the outer boarding is not in alignment with the stave ends. Moreover, anchoring of the boarding on the stave ends associated with the transversely extending wall is not advantageous.

By contrast, ’t is the object of the invention to construct a wooden building of the kind described hereinbefore in such a way that the boarding of the outer walls is directly socketed in the corner joints and the 3041 wooden building can be erected by the joining, in layers, of the log members and of the external boarding.

According to the invention, this problem is solved in that an open cavity is provided on the outside of each log member in the joint region and on the log stub, and the boarding, which extends flush with the stave ends on the outside of the framed partition wall with the curved surface facing the exterior, is provided with end tenons, each of which engages in such a cavity and is gripped by adjacent log members.

The important advantage of this construction is that the boarding of the external wall is a direct component of the corner joint to form a firmly joined bond which provides the best possible anchoring. In its aligned position the boarding together with the stave ends situated in the same direction gives the appearance of continuous log timbers to provide the impression of a genuine log cabin. The insertion of the boarding into the joint also produces a particularly sealing-tight joint with the log members. The sealing-tightness is retained even if the timber shrinks due to dryness.

The design according to the invention substantially simplifies manufacture and assembling of a timber building and is particularly well suited for batch production of components which are joined to form buildings of different size with a different base area. Advantageously, the design can also be employed for the manufacture of villas with a smooth joint. - 4 43041 In technological terms, the building constructed in accordance with the invention complies with the requirements made on a framed partition wall building intended for constant use. Problems specific to log cabins are eliminated. Stability, load-bearing capacity, sealing-tightness and durability can be ensured in a unique mariner. Boca isc of the relatively small quantity of timber required the said timber can be pressure impregnated at low cost.

The building according to the invention can be more readily assembled than log cabins. The load-bearing outer frame and the roof can be erected in a very short time and the essential part of the buiJding and fit!.ing operations of such building projects can be ’’ carried out under cover. Furthermore, the building material and fittings can be stored under cover for practically the entire building season. This fact also enables the winter period to be used as a building period.

The simple method of construction enables the user to purchase a package with the material for a building which he can then complete himself, thus effecting a saving .in cost.

The· material for a building carcase can be supplied for example in part., each of which occupy only a small ’5 amount of space. Fundamentally, it is perfectly feasible for a customer to transport a complete building carcase in a passenger motor vehicle to the building site, the log members being transported in the luggage boot and the panels on the roof of the vehicle.

To explain the advantages of the invention it can be mentioned, that the carcase of a solid log cabin of typical dimensions, and constructed from 6 inch timber baulks contains approximately 14 m^ of timber. A wooden building of corresponding size and constructed in accordance with the invention requires only approximately 3.6 m of timber. The efficient timber processing method also permits better utilization of the raw timber. Compared with a solid log cabin with a useful surface area of 2 m' a hut constructed m accordance with the invention (with high-grade insulation) gains a useful surface area 2 of approximately 3 m .

The efficient processing of the timber, improved utilization Of the raw timber and low timber consumption per m of dwelling area permit the construction in accordance with the Invention of a timber building at costs which are substantially less than the cost of log cabins. The cost of a building constructed in accordance with the invention will be so low that it can compete with most frame partition wall buildings on the market..

The external appearance of the building constructed in accordance with the invention corresponds to that of traditional log cabin. The construction of the corner joints can be much stronger and they can be more elegantly constructed. The design does not limit the size of the building, the shape or the facilities of utilizing any kind of plan, design. - 6 430 41 Embodiments of the invention are described below with reference to the accompanying drawing in which: Figure 1 shows in horizontal section, part of a building embodying the invention, the figure showing s corner joint with adjoining wall parts, Figure 2 is a view in vertical section along the line II-II, in Figure 1, Figure 3 shows a cross-section to an enlarged scale of a nogging associated with the building wall of Figure 1, Figure 4 shows a cross-section of an external board the exterior of which gives the appearance of a log cabin beam, Figure 3 shows an end portion of a board such as shown in Figure 4 as viewed from one side, and 1.5 Figures 6 and 7 show two modified embodiments of the gusset according to Figure 1.

In the building shown in part in Figure 1, the wall construction comprises external walls 1 and internal walls 2 with noggings 3 and an insulation 4 disposed therebetween.

The external walls comprise wooden boards 7 but the internal walls 2 can be constructed of plasterboard panels. Panels 5 for insulation are mounted in suitable conventional manner between the noggings 3 on the inside and at a suitable ventilation distance from the external wall 1 which comprises boards. The ventilation gap between the said panels 5 and the internal surface of the external wall is designated with the numeral 6. The material for insulation can comprise glass fibre or mineral fibre mats.

The wall construction is thus similar to that of a conventional framed partition wall. However, this building, while having a conventional wall construction and modern 1041 high-grade insulation, is provided with corner joints which are of the interlocking crossed-log construction, traditional In log cabins, and has an external appearance which is identical to that of a log cabin.

The external wall is formed of tongued and grooved boards 7 of the construction shown in Figure 4.

The timber for producing the corner joints comprises short log members 8 of identical length and each of which comprises a stave end 9, a neck 10 and an internal stub 11, The internal stubs 11 of the log members can be utilized as nogging for the external and internal walls 1, 2 and each corner joint performs substantially the same function as the conventional, interlocking, crossed-log corner joints of conventional log cabins. The log members 8 are constructed and prefabricated so that they can he easily assembled on the building site simultaneously with the wall structure comprising the external boarding 7 and the corner joints.

Each of the log members 8 is provided, over the region of its neck 10, with a rectangular rebate or notch on its upper side .extending transversely of the log memher and with a similar rectangular rebate or notch on its lower side, so that in the region of its neck 10 the log member is of smaller vertical extent than its stave end 9· A corner joint is constructed by placing log members 8 in succession one on top of the other, each log memher 8 being placed at right-angles to the log member placed previously and in vertical alignment with, the log member placed immediately prior - 8 43041 to the log member placed previously each log member being placed with its neck 10 engaging in the upwardly presented notch or rebate of the previously placed log member. The stave end of each log member lies directly upon, and in alignment with, the stave end of the log member placed just before the previously placed log member so that at a corner joint the log members can be regarded as comprising two sets, each set forming a continuation of a respective one of the two walls extending to the corner joint, with the neck 10 of each log member of one se-1' extending through a respective slot defined between adjoining rebates of a respective pair of adjacent log member., of the other set.

As shown in Figure 1, each log member 8 in the region of its neck 10, is formed, on its side directed towards the stubs 11 of the log members between which its neck passes, with a rebate or notch in which adjacent portions of the last mentioned stubs 11 engage, and each log member 8 is formed, on its side directed away from the building, with a cut awey portion, providing a flat vertical face parallel with the respective wall of the building, presented away from the building, and extending over the neck 10 and the stub 11, a cavity being defined between the last mentioned face and the opposing end faces of the notches or rebates in the upper and lower sides of the log members between which the neck extends.

As disclosed in Figure 5, the boards having a tongue 12 and groove J3 also have end tenons 14 which may be tapered, the width of which tenons can for example be 1/4 cf the width of the board. Each said tenon 14 is inserted in a respective said cavity defined between an associated log - 9 43041 member, along the outwardly presented vertical face of which the flat face of the respective board lies, and the opposing end of the slot through which the neck 10 of the associated log member passes. The boards of the two walls retained together by the corner joint bear Upon each other by means of their ends 15, the end tenons 14 of the said ends 15 being mitre cut to form good seating.

The necks 10 have vertical boreholes arranged in one line so that a respective continuous bolt can be inserted through the log members of each corner joint for the vertical connection between the log members and the walls.

The flanks of the necks 10 against which the end tenons 14 bear may, as described above, be flat, and the end tenons 14 can be secured on the said flat sides of the necks 10, for example hy means of nails 16. However, as shown by the following embodiments, the nails or other fastening means, for example glue can be omitted if the end tenons 14 and the cooperating surfaces of the necks 10 are so shaped that the tenons 14 are firmly locked in the corner joints when the walls and log members are assembled, the stave ends 9 and the stubs 11 of the log members 8 forming head ends which are capable of absorbing torsion and thrust forces.

To ensure precise positioning of the boards with respect to the associated log members and to form the ahovementioned non-positive join between the necks 10 and the end tenons 14, each of the latter can be provided, on its face facing the neck 10 of the associated log member, with one or more vertical grooves or ribs 19, engaging corresponding vertical ribs or goooves respectively formed on the outwardly presented face of the neck of the associated log member 8, (see Figures 1 and 5).

In place of the illustrated construction of the necks and rearward stubs 11, it is possible for some other shape to be developed for example a so-called tenon gusset shape or the shapes shown in Figures 6 and 7, of a high-tensile dovetail connection between the end tenons of the boards 7 and the necks 10. In this case, it is not necessary to provide a gusset with an inner gusset stub which extends into the space between the outer wall and the inner wall 2 as shown in Figure 1. A cold bridge in the internal corners of such an embodiment can be avoided by attaching insulating material between the inner corners of the necks 10 and the adjoining corners of the inner wall 2. Cold bridges in the embodiment of Figure 1 can also be avoided by chamfering the stubs 11 at the inner corners and by applying filling insulating material.

Suitable seals can be applied to the slanting joint 20 between the timber boards 7 and the stave ends 9 of the log members and in the slanting joints 21 between the stave ends 9. ,’5 The inner endfaces of the stubs of the log members are designated by 11' in Figure 2 and the internal surface of the stubs 11 of the log members are designated by 11.

To facilitate assembling and locating the position of the insulating panels 5, the noggings 3 can be provided with vertical grooves 22 of the shape shown in Figure 3, i.e. 041 grooves with a curved, chamfered internal edge, so that the insertion of the edges of the panels 5 into the groove from the interior of the building is facilitated.

Figure 6 Shows not only a modified embodiment for the connection of the end tenons It of the boards 7 with the log members of the corner joint, but also shows a modification of the internal wall 2 in diagrammatic form, which has basically the same construction as the external wall 1, i.e. it comprises boards so that the inside of the building (for example a week-end house) gives the impression both from the exterior and from the interior of being built of solid timber. The insulation between the walls 1, 2 can comprise plastics which is foam expanded in situ but the internal wall 2 can of course also be mounted on noggings of the kind illustrated in Figures 1 to 5 and the insulation can comprise of modern high-grade insulating materials such as fibre wool.

Figure 6 and 7 are simplified views of the joint between a corner joint and the walls of a building which meet in. the corner joint, shown as a horizontal section along the centre-line of a board 7· These Figures should be compared with Figure 1 to provide a better understanding.

Figure 1 shows at 25 a dummy intermediate joint which can be disposed at a suitable position, for example opposite a transversely extending internal wall or adjoining an entrance at an external wall. The simple intermediate joints comprise short prefabricated log members 26 and the boards are constructed with tapering end members 27 to permit overlapping in the dummy joint 25· The log members 26 have annular grooves 28 and the end members 27 of the boards are provided with cuts for insertion into the annular grooves 28. The intermediate joints are of dummy construction in the sense that they do not have nor call for a continuation in the form of a transversely extending wall but are genuine in the sense that they provide the wall with mechanical strength and allow settling of the log members 8 and of the boards of tho external walls 1 when the timber dries. Drying of the walls therefore no longer results in leakages. The bolts in the boreholes 17 can be used for pulling together the wall elements after drying.

The statements above disclose that the building construction according to the invention is identical to a log cabin not only in appearance but also in its function.

The building constructed in accordance with the invention can be compared with a log cabin in which the superfluous ?0 timber of the external wall carpentry is omitted so that only wooden panels are produced between the gussets; the building according to the invention can however also be compared to a framed partition wall building which has the advantages of a cimber building (appearance of the wails and lowering thereof when drying).

As already mentioned, all elements for a building constructed in accordance with the invention can be prefabricated, i.e. the building timber can be prepared - 13 41 to the correct dimensions and shapes. Assembling the boards 7 and the log members 8 -is conveniently performed in the same manner as assembling the log members of a log cabin. The difference however is that each log member 8 and associated board 7 does not consist of a single piece and another important difference is that the elements are of substantially less weight than log timbers cfldean therefore be handled by one person who need not have expert training.

The operation of assembling can be performed in such a way that for each corner joint a half-log member (which can be produced by longitudinal splitting of a log member 8 or by prefabrication) is placed on the floor or ground and a half-board (which can be formed by longitudinal splitting of a board 7 or prefabricated to provide the same form) is fitted to the half-log member, then a full log member 8 with an associated board 7 is fitted across the half-log member, the boards being arranged at right angles to each other on the floor and their neck-shaped end tenons 14 fitting between the necks 10 and corresponding slots of the log. members 8.. The operation is continued with entire log members and entire boards which are jointed to the elements situated therebelow, the log members firmly holding the boards. A half-log member 8 and a half-hoard can again be used as the top termination to adapt the level of the walls which meet at the corner. After the assembling operation the wall structure (including cross-beams and dummy log members 25 in the case of long walls) form a stable structure on which a roof is erected. The internal work for the construction of shelving, the installation of insulation and of the internal walls and the like can then be performed In a manner which is conventional for framed partition wall buildings. The assembling- operation for erecting a building with corner joints and walls in the manner shown in Figure 6 does not differ substantially from the description above and can be easily uriderstood by reference to this description.

The log member 8 illustrated in the drawing and formed so as to make with adjacent log members 8 a rebated quarter joint gusset can also be constructed in accordance with the invention as a single joint corresponding to a gusset joint with trimmed stave ends 9. Since the gusset necks 10 and the neck-like end tenons 14 of the boards 7 are constructed so that they form a conventional dovetail or tongue and groove joint, for example when combined in accordance with Figure 7, it results in a torsion and thrust force resisting stable positive connection between the log members themselves as well as between the said log members and the wall elements. Furthermore, the boards 7 can be extended at the ends 15 so that the end tenon 14 forms ?0 a neck and the extension conceals a correspondingly planed side of the stave end 9 (in a manner similar to that in which the stub 11 is concealed by the board). An integral component can also be constructed by prefabrication (for example by glueing) rom a log member 8 and a panel 7.

Claims (13)

1. WHAT WE CLAIM IS:1. A wooden building of log cabin appearance with corner joints comprising short log members whieh are rebated and are mounted id alternating superjacent crossed-over configuration, have outwardly pointing stave ends and respective oppositely directed stubs with walls affixed thereto, said walls comprising horizontally extending boards, and in which corner joints an open cavity is provided on the outside of each log member in the region of the corner proper and each board, is provided with end tenons, each of which engages in a respective said cavity and is gripped by adjacent log members.

2. A building according to Claim 1, in which the log members and the end tenons of the boards are so constructed that they form a torsion and axial thrust resistant positive joint in the corner joint for the log members relative to each other and for the log members and the boards relative to each other.

3. A building according to Claim-2, in which the corner joints have the form of cross-joints in cross-joint connections.

4. A building according to Claim 2, in which, in the corner joints,' the joints between the horizontally extending boards and the log members are shaped as dovetail, comb or tenon joints.

5. A building according to any of the preceding claims, in which each log member has a relatively short stub which is orientated inwardly from the joint neck and is widened relative thereto to overlap part of a board and to support the latter and forms a head for absorbing axial thrust in the joint.

6. A building according to Claim 2, in which the thrust-resistant joint between each board and the respective log members is reinforced by fastening means which connect the relevant boards to the relevant log members in the joint.

7. A building according to any of the Claims 2 to 5, in which the axially resistant joints between the log members and the end tenons of the boards include comb joints each comprising a plurality of substantially transversely extending grooves and tongues.

8. A building according to any of the Claims 2 to 5, in which the axially resistant positive joints between the log members and the boards are dovetail, pin, comb or tenon joints or include such joints which advantageously form part of the joints between the log members.

9. A building according to any of the preceding claims, in which the building has the form of a framed partition wall building in which the external walls comprising boards form a base for noggings and internal walls at a distance from the external walls, the ventilation gaps and insulation of conventional framed partition wall buildings being provided at a distance from the external walls.

10. A method of constructing a building of log cabin appearance, according to Claim 1, in which method, to - 17 41 erect the corner joints of the building the required number of short log members,' are produced from timber logs and previously shaped to have the form of end sections, of appropriate length, of logs of the form used for conventional log cabin construction, in such a way that on assembling a plurality of such log members into a joint each pair of two adjoining parallel log members forms a cavity which is open from the joint side with respect to the relevant wall, hoards in the form of log skins being used to erect the external walls of the building, one end part of each of such boards which is to be connected to the relevant corner joint being preformed for insertion into the cavity between two adjoining parallel log members and to form.an end tenon which fills said cavity to complement said log members so as to form together, therewith a joint which is resistant to torsion which occurs in the wall and the joint and in which the torsional forces are absorbed by positive engagement, conventionally employed for the logs of log cabins, between:the log members and by positive engagement of the log members around the end tenon of the relevant boards disposed between said elements, the relevant joint being constructed mainly in the same manner as a conventional timber joint by assembling a number of log members, the wall adjoining the joint being constructed by a corresponding number of separate boards the shaped end members of which are joined between adjoining log members and are connected thereto in the sequence in which the said log members are placed one upon the other. - 18 43041

11. A method according to Claim 10, in which the log members and the end tenons of the boards are preformed so that in their entirety they form a positive joint which is resistant to thrust, forces which occur between the j'oint 5 and the wall, for example a transversely extending tongue-groove j'oint with a pin point connection or a dovetail connection between log members arid the corresponding boards when these are assembled.

12. A building substantially as hereinbefore described with 10 reference to and as shown in the accompanying drawings.

13. A method of constructing a building, as claimed in Claim 10 and substantially as hereinbefore described with reference to the accompanying drawings.