TECHNICAL FIELD

The present invention is related generally to a wall module for a multistorey building, a multistorey building produced with such wall modules and a method for producing such a wall module.

DESCRIPTION OF THE PRIOR ART

It is known to utilize pre-fabricated building elements in the building of multistorey buildings. With pre-fabricated building element is usually meant a part of the building system which is manufactured in a factory and is transported to the building site in order to be erected to a building together with parts built on site.

It is known to build multistorey buildings with pre-fabricated modules which have been finished in a factory. Often the modules are so called volume modules which comprise floor, walls and roof. The volume modules may be manufactured with a frame of any one of a large number of different materials such as wood, metal and concrete. The surfaces inside the volume modules may be finished to a high degree inside the modules. Usually slits occur in the joints between the volume modules as they are produced with a limited accuracy in outer dimensions. Transports from the factory to the building site are limiting for how large the volume modules may be if expensive special transports are not used. The limited size of the volume modules results in joints through large rooms in the building, which results in the above mentioned slits. These slits in the joints between volume modules have to be covered after the volume modules have been joined together to a multi-storey building.

An alternative to pre-fabricated volume modules is building using pre-fabricated wall modules and floor modules. Pre- fabricated wall modules and floor modules occupies considerably less space than volume modules and are thus easier to transport from the factory to the building site. This also results in that it is possible to create buildings without joints through the rooms. Wall modules and floor modules may for example be produced from concrete. It should be noted that pre¬ fabricated wall modules according to prior art requires more or less supplementary work in connection with assembly and finishing of the building. Especially, extensive work is required in order to achieve sufficient accuracy in dimensions of the building and for sealing of the building. Further, in connection with building with modules of concrete supplemental concrete casting is often required in order to connect components and modules with each other. All such supplemental work makes the building more expensive and also results in an increasing difficulty in preserving for example an in advance finished surface layer. For wall modules of concrete pre-fabrication according to prior art may mean that the concrete wall is casted in a factory and that the inside of the wall is filled, or is provided with a sheet material of gypsum or similar, as a ground for further painting, papering or similar after assembly and joining at the building site.

When using pre-fabricated building modules it is important to achieve a sufficient strength of the building. According to the prior art this has been achieved by an initial erection of a load- bearing structure in which the pre-fabricated building modules are mounted. Another known technique to provide a sufficient strength is to fill for example remaining shell moulds with concrete after they have been mounted in the correct position in the building.

A problem when building multistorey buildings with pre¬ fabricated wall modules is, as has been indicated above, that it

is very difficult to achieve sufficient accuracy in dimensions of the separate wall modules so that the need for additions, such as filling of slits between wall modules, may be minimized. If sufficient accuracy in dimensions of the separate wall modules is achieved it is desirable that the pre-fabricated building elements are positioned with very large accuracy in relation to each other so that it is possible to achieve such an accuracy in dimensions of the finished multistorey building that supplementary work is minimized. In order for supplementary work to be minimized and possibly avoided and for the building to be erected in an efficient way the following demands must be fulfilled. Firstly, it is required that the wall modules and the floor modules which are used to build the multi-storey building, are joined in a way such that forces may be transferred between the wall modules. Secondly, it is required that the wall modules can be built together sufficiently well for fire, sound and air sealing to be achieved. Thirdly, it is required that the wall modules are designed in such a way that completely finished surface layers can be arranged in advance on the wall modules. Common for the known techniques, using any form of pre-fabricated wall modules, is that extensive manual supplementary work and completions of the pre-fabricated modules in relation to each other is required in order to achieve the required accuracy in dimensions, i.e. the solutions according to the prior art requires extensive work at site in order to achieve a completed building as an end result.

The Swedish Patent Application 0200850-6 shows a wall element comprising two at a distance from each other arranged wall plates and a cavity between these intended for filling with concrete when the concrete element is arranged at a desired position in the building. The wall elements require work at the building site in order to achieve a completed building.

In the Swedish Patent Application 0001623-8 a method of erecting system buildings in isolating concrete by using massive

wall blocks and hollow cantilever floorstructure/roofblocks of concrete for the creation of open inner rooms, which may freely be divided with non-load-bearing walls. The blocks are oriented in position in connection with piling on or next to each other using a notch and tenon whereupon joining is performed.

SUMMARY OF THE INVENTION

An object with the present invention is to provide a load-bearing pre-fabricated wall module which enables the building of the buildings with a high accuracy in dimensions with a small effort on the building site.

A further object with the present invention is to provide a load- bearing wall module which can take up primarily vertical loads, in order to enable the building of multi-storey buildings by piling wall modules on each other in the vertical direction.

A further object with the present invention is to provide an essentially fully pre-fabricated self-bearing wall module which is prepared for living and which can be manufactured in an easy and rational way.

Another object with the present invention is to provide a wall module with a large load-bearing capacity and relatively small thickness.

A further object with the present invention is to provide a method for manufacturing of a wall module which can be used for building buildings with a high accuracy with a small effort on the building site.

These objects are achieved with the wall module that is defined in the independent claim 1.

A basic idea with the present invention is the arrangement of the mentioned pillars which are connected with concrete in order to enable a wall module with very high accuracy regarding the outer dimensions in the vertical direction and in the horizontal direction. By means of the pillars the wall module may carry very large vertical loads which enables wall modules to be arranged on each other in a vertical direction in such a way that the wall modules will carry essentially the whole weight of the multi¬ storey building. In other words the wall module according to the invention is essentially totally self supporting. The pillars according to the invention further enables the creation of a wall module having a standardized thickness. The pillars enables the thickness of the walls to be relatively small at the same time as the walls are sufficiently strong to carry loads from the above lying storeys in the multistorey building. This results in that similar wall modules as those that are used for the external walls also can be used for the interior walls without them essentially limiting the available surface for living. With a wall module according to the invention design, planning, production and transport of the wall module is thereby simplified compared with wall modules according to the prior art.

The wall module according to the present invention is intended for multistorey buildings. The wall module according to the invention extends essentially parallel to a centre plane and has two short sides, an upper side and an underside. The wall module is characterized in that it comprises at least two pillars, which each essentially extends from the upper side to the underside, a reinforcement which extends between the pillars and is attached to the pillars, and concrete which at least partly surrounds the reinforcement, extends between the pillars and is attached with the pillars. At their upper ends the pillars form supporting means on the upper side of the wall module, which are arranged to support a wall module arranged above.

With a wall module according to the invention a very high accuracy regarding the dimensions of the wall module is achieved. Especially, the vertical height of the wall module is defined in a very exact way due to the arranged pillars. The wall module may thus be arranged for example essentially directly on another wall module, for the building or the mounting of a wall in a multistorey building without the need for any supplementary work or incorporation of additional components or concrete. The pillars may be produced with a high accuracy regarding the length as they for example may be cut with a high accuracy from a longer pillar. The reinforcement which is arranged between and connects the pillars results in the pillars being fixed in relation to each other, so that also the horizontal dimension of the wall module may be defined with a high accuracy before concrete is arranged surrounding the reinforcement. The wall module has a length axis being parallel to the upper side and the underside, a height axis being parallel to the short sides and a width axis being perpendicular to the centre plane.

According to a further embodiment of the invention the pillars are at least partly filled with concrete. In this way the stiffness and the carrying ability is further increased. By the pillars being filled with concrete a further securing of the pillars in relation to the concrete is also achieved. Thus, the pillars may advantageously have at least one lateral opening arranged in such a way that the concrete that is arranged in each pillar is directly connected with the concrete of the wall module outside each pillar.

According to an embodiment of the invention the pillars are tubular. In this way a pillar with a high accuracy in dimensions, high bending stiffness and a high rotational stiffness is achieved, which contributes to a high accuracy of the wall module. A tubular pillar may also carry large vertical load. Advantageously, the pillars may have an essentially rectangular cross-section, which further emphasize these desired positive

qualities regarding stiffness and carrying ability. It is of course possible, within the scope of the invention, to let the pillars have an arbitrary cross-sectional shape.

According to a further embodiment the pillars form supporting means at their upper ends on the upper side of the wall module, which supporting means are arranged to support a wall module arranged above. The pillars are preferably vertical when the wall module is arranged in its intended position of use. They are, thus, suitable for taking up very large vertical loads. The supporting means then forms so called point bearings and may be designed with an essentially plane horizontal surface, i.e. a surface which is perpendicular to the lengthwise direction of the pillars. The above mentioned vertical connection devices may, for example, be arranged on or form such a supporting means.

According to a further embodiment of the invention the reinforcement comprises a primary reinforcement and a secondary reinforcement. Preferably, the primary reinforcement comprises at least one essentially straight reinforcement bar which extends between and is connected to the pillars. In this way the horizontal length of the wall module may be defined in an exact way and primarily the distance between the pillars is exactly defined. Thereby it is possible to allow the pillars in on each other arranged wall modules to lie essentially exactly in line with each other which is important for the ability to carry large loads and thus for the strength of multistorey buildings. Further, said at least one reinforcement bar may extend essentially parallel to the upper side.

According to a further embodiment of the invention the secondary reinforcement comprises at least one reinforcement net which is arranged between the pillars and which extends essentially parallel to the centre plane. Such a reinforcement net is intended to strengthen the concrete and may preferably

comprise openings made in advance for passages, e.g. for windows or doors, through the wall module.

The wall module may have an upper part which have a width perpendicular to the centre plane and which extends along the upper side, and a main part below the upper part, which main part has a width which extends perpendicular to the centre plane and is larger than the width of the upper part. In case the wall module has such an upper part a shelf is provided between the main part and the upper part. Such a shelf is useful for the arrangement of a floor structure, which for example may form a roof and/or a floor and which may rest on the shelf. Preferably, the primary reinforcement comprises at least one reinforcement bar which extends through the upper part. Thereby the upper part gets a high strength and thereby may the above mentioned passages in the main part up to the upper part be provided without the strength of the wall module being jeopardized.

According to a further embodiment of the invention may at least one sealing strip be arranged on the upper part at least on the side of the upper part being parallel to the centre plane, in order to provide sealing against a floor structure which is arranged against the upper part. Alternatively, sealing strips may be arranged on the floor structure. When wall modules are put together to a multistorey building said sealing strip will, thus, be situated between the upper part and the floor structure. By arranging one or more such sealing strips in advance on the wall module fire sealing, air sealing and sound sealing between different apartments is provided in a simple way. Furthermore, no supplementary work with mounting sealing strips at site, when the wall modules are assembled to a multistorey building, is required. As the tolerances on the outer dimension of the wall modules are small it is also possible to use thin sealing strips, arranged in advance, between wall modules and the floor structure. The small tolerances further enables finished surface layers as the slits between the wall modules becomes small.

According to a further embodiment of the invention the wall module has an lower part which extends along the underside and which has a width which extends perpendicular to the centre plane and is smaller than the width of the main part. By the wall module having such an lower part it is adapted to be placed above a similar wall module. When two such wall modules are arranged with one above the other, a floor structure may be arranged on the shelf between the main part and the upper part of the lower of the wall modules. Then the floor structure is also arranged in the indentation which is formed by the lower part of the upper of the wall modules. The lower part may be arranged to be situated below an upper surface of the floor structure so that a free passage through the passage is provided also at floor level. Preferably the primary reinforcement may comprise at least one reinforcement bar which extends through the lower part. Thereby, it is possible to arrange said passage through the main part extending all the way down to the floor level without jeopardizing the strength of the wall module. Further, at least one sealing strip may be arranged on the lower part at least on the side of the lower part being parallel to the centre plane, in the corresponding way as for the upper part, in order to provide sealing against a floor structure which is arranged against the lower part. The sealing strip may of course also be arranged on the floor structure as mentioned above. Such as sealing strip gives the same advantages as has been described above in connection with the sealing on the upper part.

According to a further embodiment of the invention the length of the wall module, parallel to the centre plane, the upper side and the underside, is larger in the main part than in the upper part and in the lower part. By the length of the wall module being larger in the main part than in the upper part and the lower part a shelf or an indentation of the wall module is achieved also on the short sides, which indentation can be used for horizontal connection devices which will be described below. Further, the

length of the wall module, parallel to the centre plane, the upper side and the underside, may be limited by the pillars in the lower part and the upper part. By arranging the pillars in this way in the wall module surfaces are provided at the short sides of the wall module on which surfaces said horizontal connection devices may be fastened. As these surfaces may be hided with a floor structure the surfaces of the wall modules being exposed in the apartment may be completely finished.

According to a further embodiment of the invention said short side is arranged for contact against an adjacent wall module in the multistorey building, wherein at least one of said wall modules comprises a pre-mounted sealing strip. With such a sealing strip arranged in advance on at least one of the two mating sides an efficient sealing is provided between the wall modules without any sealing work being required in connection with the mounting. It should be noted that the short sides may extend essentially perpendicular to the centre plane for assembly of the wall modules in line with each other. The short sides may, however, also extend in a plane which forms an angle with the centre plane, wherein two adjacent wall modules also forms an angle to each other, which angle may be between 0 and 180 degrees. The angle between the short side and the main part is adapted to the intended angle between adjacent wall modules. It is, of course, also possible to arrange a short side of a wall module against the long side of an adjacent wall module with an arbitrary angle between the wall modules.

According to a further embodiment of the invention the wall module comprises at least one of a first type of horizontal connection device and a second type of horizontal connection device, wherein the first type of horizontal connection device is arranged for connection with the second type of horizontal connection device in an adjacent wall module in the multistorey building. The horizontal connection devices are intended to connect adjacent wall modules and to keep these at an

appropriate distance from each other so that essentially horizontal walls are provided. Preferably, at least one horizontal connection device is arranged on each one of the pillars. The pillars comprise a stable basis for the horizontal connection device. Preferably, the pillars are arranged so that they form the short side of the wall module in the upper part and the lower part. There may be arranged one or more further pillars apart from the pillars at the short sides of the wall module.

According to a further embodiment of the invention the pillars are provided with a first type of vertical connection device on the pillars on the upper side of the wall module and a second type of vertical connection device on the pillars on the underside of the wall modules, wherein the first type of vertical connection device is connectable with the second type of vertical connection device so that the wall modules may be arranged on top of each other connected with the vertical connection devices in at least one horizontal direction. With such vertical connection devices a locking in the horizontal direction, and possibly also in the vertical direction, may be provided between two wall modules when they have been placed one above the other. Preferably, the first or the second type of vertical connection device may be adjustable in relation to the pillars along and perpendicular to the centre plane. The adjustability gives a possibility to take into account systematic errors which may occur during assembly.

According to a further embodiment of the invention the wall module is finished for living and for assembly with other wall modules to said multistorey building. The main part of the wall module, also including the short sides, is the part or the parts of the wall module that may be exposed to inner spaces in the completed building. Preferably, the wall module may comprise a surface layer which is arranged on the side or the sides of the main part which are intended to face towards an apartment or other inner spaces in the building and which are finished for living. By finishing the surface layer for living the supplementary

work during assembly of the building site is minimized. With finished for living is meant that at least the final surface treatment regarding wallpapers and/or painting has been performed. Further, the wall module may comprise a facing which is arranged on the side or the sides of the wall module which are intended to be outside on the multistorey building. In this way also the outside of the wall module may be completely or partly finished before it is mounted at the building site.

According to a further embodiment of the invention the wall module comprises the installation component/components which belongs/belong to said wall module and which are finished for living. Said installation components may comprise at least a pipe for electric cables, which pipe is arranged in the wall module. By one or more pipes for electric cables being arranged in advance in the wall module the work at the building site is minimized. The pipes for electric cables may end adjacent to any one of the short sides of the wall module. With entrances adjacent to the short sides of the wall module the connection of electric cables from one wall module to electric cables in an adjacent wall module is simplified. The pipes for electric cables may preferably also extend through the wall module from one short side to another. In this way they may be connected to a wall module in one short side and further to another wall module from its other short side. Furthermore, electric cables for mains voltage may be arranged in the pipes for electric cables. This further decreases the work that is required when the multistorey building is built. Preferably, the electric cables may be arranged in a contact of a first kind in one end and a second kind in the other end so that a contact of the first kind in a first wall module may be connected with the contact of the second kind in a second wall module. In this way the electric cables may be connected rapidly without any risk for faulty connections.

According to a further embodiment of the invention the wall module comprises at least one hot water pipe for hot water

central heating, which extends from the upper side of the wall module to the underside of the wall module. With such hot water pipes for hot water central heating, water for heating may easily be directed up through the multistorey building. The hot water pipes from the upper side of a first wall module may be connected with the hot water pipes from the underside of a second wall module which is placed above the first wall module. Preferably, the hot water pipes are arranged on the inside of a facing. The facing, thus, provides sufficient heat isolation for the hot water pipes.

According to a further embodiment of the invention connection pipes are arranged connected with the hot water pipes, which connection pipes are arranged in the wall module. With such connection pipes radiators may be connected to the hot water pipes. Furthermore, the hot water pipes may be provided with a pipe connection device of a first sort on the upper side of the wall module and with a pipe connection device of a second sort on the underside of the wall module, so that the hot water pipes on the underside of a first wall module may be connected to the hot water pipes on the upper side of a second wall module. With such pipe connections the connection of hot water pipes is facilitated.

According to a second aspect of the invention a wall module for a multistorey building is provided, wherein the wall module extends essentially parallel to a centre plane and has two short sides, an upper side and an underside. The wall module is characterized in that it comprises at least two pillars, wherein each of the pillars essentially extends from the upper side to the underside, a reinforcement which extends between the pillars and is attached to the pillars, and concrete which at least partly surrounds the reinforcement and extends between the pillars.

A wall module according to the second aspect of the invention may be combined with any of the features that has been

described in connection with the first aspect of the present invention.

According to a third aspect of the present invention a multistorey building is provided comprising a plurality of wall modules of the above described type. The wall modules may be performed in a standardized thickness which allows rational design, production, transport and mounting.

According to a fourth aspect of the present invention a method is provided for production of a wall module, comprising the steps of connecting two essentially parallel pillars with a reinforcement, to place the pillars with the reinforcement in a mould which defines a centre plane, an upper side, an underside and two short sides, so that the pillars essentially extends from the upper side to the underside and so that the reinforcement is essentially parallel with the centre plane, and to pour concrete in the mould so that it at least partly surrounds the reinforcement, extends between the pillars and is connected with the pillars. The pillars form at their upper ends supporting means on the upper side of the wall module, which supporting means are arranged to support an above arranged wall module.

With the method according to the invention a wall module is provided which enables fast and efficient building of a multistorey building which requires a minimum of supplementary work at the building site. Further developments of the method is defined in the dependent method claims.

According to a fifth aspect of the present invention a method for production of a wall module is provided, comprising the steps of connecting two essentially parallel pillars with a reinforcement, to place the pillars with the reinforcement in a mould which defines a centre plane, an upper side, an underside and two short sides, so that the pillars essentially extends from the upper side to the underside and so that the reinforcement is

essentially parallel to the centre plane, and to pour concrete in the mould so that it at least partly surrounds the reinforcement and extends between the pillars.

It is of course possible to apply applications together with the reinforcement before casting. Examples on such applications are electric boxes connected with electric pipes, and water pipes. By applying such applications in the reinforcement before casting they are easily integrated in the wall module.

The features that have been described above may of course be combined in the same embodiment where applicable.

In the following preferred embodiments of the invention will be described with reference to the appended drawings.

SHORT DESCRIPTION OF THE DRAWINGS

Fig. 1 shows schematically a part of a floor in a multistorey building where wall modules according to an embodiment of the invention have been used.

Fig. 2a and 2b shows in larger detail a wall module according to an embodiment of the present invention.

Fig. 3 shows in larger detail the wall module in Fig. 2a and 2b in cross-section.

Fig. 4 is an exploded view over the wall module in Fig. 2 and 3.

Fig. 5a-5c shows a wall module with three pillars.

DESCRIPTION OF PREFERRED EMBODIMENTS

In the following description of preferred embodiments of the invention similar details in the different figures will be denoted with the same reference numeral.

Figure 1 shows schematically a part of a floor 1 in a multistorey building where wall modules 2 according to an embodiment of the invention have been used to create interior walls 3 and external walls 4. All or essentially all walls 3, 4 are load-bearing. The wall modules 2 stand on one or more underlying wall modules 2 or a foundation (not shown). Each wall module 2 has two short sides 6, an upper side 7 and an underside 8, as is evident more clearly from Figs. 2-4. Each one of the wall modules 2 is at the upper side 7 at both short sides 6 connected with at least one adjacent wall module 2. In some cases the wall modules 2 are connected with another wall module 2 at the upper side 7 between the short sides 6.

Figure 2a shows in larger detail a wall module 2 according to an embodiment of the present invention. The wall module 2 has two short sides 6, an upper side 7 and an underside 8. As is evident by Figs. 2a and 2b the wall module 2 has an upper part 9 which extends along the upper side 7, a lower part 10 which extends along the underside 8 and a main part 1 1 which is arranged between the upper part 9 and the lower part 10. The main sides 12 which are defined by the short sides 6, the upper side 7 and the underside 8 defines in turn a centre plane which is parallel with the mains sides 12. The perpendicular 13 to the centre plane is shown in Figs. 2a and 2b. The wall module 2 in Fig. 2a is provided with a door 14 which extends through a passage of a part of the main part 1 1 from the boundary between the lower part 10 and the main part 11.

Figure 2b shows another wall module 2 which, in contrast to the wall module 2 in Fig. 2a, is provided with a window 15 in the main part 1 1 and, in the shown embodiment, on the outside is provided with a facing 60 which comprises an insulation. As is

indicated in Fig. 2a as well as in Fig. 2b the thickness of the wall module 2 along the perpendicular 13 is equal in the upper part 9 and in the lower part 10 and less than the thickness of the wall module 2 along the perpendicular 13 in the main part 1 1. In the boundary between the main part 1 1 and the upper part 10 there is a shelf 72 on which it is possible to arrange a floor structure 75 which can be carried by the wall module 2 together with other wall modules 2. In the upper part 9 of the wall module 2 there is arranged a first type of vertical connection device 16. The wall module 2 has a length axis 61 , which extends parallel to the centre plane, the upper side 7 and the underside 8, as well as a height axis 62, which extends parallelly with the centre plane perpendicularly to the length axis 61 , as is shown in Fig. 3. In the embodiment shown in Fig. 2a, Fig. 2b and Fig. 3 the length axis 61 and the centre plane extends perpendicularly to the short sides 6. It should, however, be noted that the short sides 6 also could extend parallelly to a plane which forms an angle with the centre plane.

On the upper part 9 of the wall module 2 there is, in the shown embodiment, arranged an upper sealing strip 74, which is arranged to seal against the floor structure 75 which is put against the upper part 9. A corresponding lower sealing strip 74 is arranged on the lower part 10 of the wall module in order to seal against another floor structure 75 which is arranged against the lower part 10. Further, a vertical sealing strip 74 may be arranged on one or both of opposing sides, short sides 6 and/or main sides 12. The upper part 9 and/or the lower part 10 may comprise means for lifting and transportation of the wall module 2. Such means will, after mounting, be hidden by the floor structure 75. It is of course also possible to arrange sealing strips on the floor structure 75.

The wall module 2 comprise also other, in advance, mounted components, such as the above mentioned door 14 and window

15, and installation components, electric cables arranged in

electric cable pipes 24, see Figure 4, with different connection boxes, contacts and sockets, see below, radiators, possible ventilation openings etc.

Figure 3 shows in larger detail the wall module in Fig. 2a in cross-section. The wall module 2 has a first pillar 17 and a second pillar 18 which each extends essentially vertically from the underside 8 of the wall module 2 to the upper side 7 of the wall module 2. In the shown embodiment the pillars 17, 18 are tubular and has an essentially rectangular cross-sectional shape. The pillars 17, 18 may be manufactured from any suitable material, for example metal, such as steel or any fibre material. The pillars 17, 18 may comprise supporting means at the upper and lower ends respectively. Such support means may form so called point bearings and may be designed as or with an essential plane horizontal surface, i.e. a surface which is perpendicular to the lengthwise direction of the pillars 17, 18.

Each wall module 2 also comprises a reinforcement 19, for example of metal such as steel or any fibre material. The reinforcement 19 comprises a primary reinforcement which in the shown embodiment is comprised of one or more essentially horizontal reinforcement bars 22 which extends between and are connected with the first pillar 17 and the second pillar 18. The reinforcement 19 also comprises a secondary reinforcement which in the shown embodiment is comprised of a first reinforcement net 63 and a second reinforcement net 64, see especially Figs. 5b and 5c, which are arranged between the pillars 17 and 18 and extend essentially parallel with the centre plane. These reinforcement nets 63, 64 comprises in advance made openings 66 for passages, for example for windows or doors, through the wall module 2. In Fig. 5 is also shown an extra strengthening reinforcement 65 above such an opening 66.

On the upper side of each one of the pillars 17, 18 there is arranged the first type of vertical connection device 16. The

other type of vertical connection device 20 is arranged inserted in the pillar 17, 18. The first type of vertical connection device 16 is arranged to be connected with the second type of vertical connection device 20 which is arranged on the underside 8 of another wall module 2. The vertical connection devices 16, 20 prevents, when they are connected, motion between the wall modules 2 in the perpendicular direction of the centre plane and in the direction of the length axis 61 . Such as is indicated in Fig. 2a, 2b and 4 the length of the upper part 9 along the length axis 61 is equal to the length of the lower part 10 along the length axis 61. The length of the upper part 9 and the length of the lower part 10 is less than the length of the main part 1 1 along the length axis 61. In the upper part 9 on the short side 6 of the first pillar 17 there is arranged a first type of horizontal connection device 29, wherein a second type of horizontal connection device 30 is arranged in a corresponding position on the short side 6 on an adjacent wall module 2. The first type of horizontal connection device 29 is designed to allow connection with the second type of horizontal connection device 30 for attachment of adjacent wall modules 2 in the multistorey building. The different connection devices 16, 20, 29 and 30 are all arranged in such a way and in such a position that they will be hidden by the floor structure 75 after mounting of the wall modules 2.

Fig. 4 is an exploded view over the wall module 2 in Fig. 2 and 3. Fig. 4 shows the first pillar 17, the second pillar 18 and the reinforcement 19. Fig. 4 shows the second type of vertical connection device 20 which is to be inserted in the lower part of each one of the pillars 17, 18 and be connected in the pillars 17, 18, for example by welding. In Fig. 4 electric cable pipes 24, which are arranged to be casted into the wall module 2, is also shown. A first pipe end with a contact 25 of a first type is arranged in one of the lower corners of the wall module 2 while a second pipe opening with a contact 26 of a second type is arranged in the other lower corner of the wall module 2. There is

also arranged electric boxes 27 on a plurality of positions along the electric cable pipe 24. In Fig. 4 horizontal connection devices 29, 30 are also shown. The concrete 73 is shown as a separate component which in liquid form is to be joined with the other components in the wall module 2. In Figure 4 hot water pipes 76 for hot water central heating are also shown, which pipes 76 are to be arranged in the wall module 2. The hot water pipes 76 are covered with a facing 60. Connection pipes 77 are arranged connected with the hot water pipes 76, which connection pipes 77 are intended to be arranged through the wall module 2. Radiators may be connected to the connection pipes 77 on the side of the wall module 2 which is to be facing a room in the multistorey building. The hot water pipes 76 are provided with a pipe connection device 83 of a first sort on the upper side 7 of the wall module 2 and with a pipe connection device 84 of a second sort on the underside 8 of the wall module 2, so that the water pipes 76 on the underside 8 of a first wall module 2 can be connected with the hot water pipes 76 on the upper side 7 on a second wall module 2.

During manufacturing of a wall module according to the invention the reinforcement 19 is attached in the pillars 17, 18 on which the vertical connection devices 16, 20 are arranged. The pillars 17, 18 with the reinforcement 19 and the vertical connection devices 16, 20 is then arranged in a mould which encloses the reinforcement 19 and the pillars 17, 18 on the short sides 6, the underside 8 and the main sides 12. Thereafter concrete 73 is poured into the mould so that the reinforcement 19 is enclosed by concrete 73. After the concrete 73 has hardened the finished wall module 2 is taken out from the mould. As was mentioned above the pillars 17, 18 are tubular. When the liquid concrete 73 is poured into the mould the pillars 17, 18 will, thus, also at least partly be filled with concrete 73. Preferably, the pillars 17, 18 has at least one lateral opening, wherein the concrete 73 can flow through these so that the concrete 73 in the pillars 17, 18, when it has solidified, will be

directly connected with the concrete 73 outside each pillar 17, 18.

Fig. 5a-5c shows an embodiment of a wall module 2 which comprises three pillars 17, 18 and 28, i.e. an extra intermediate pillar 28. The reinforcement bars 22 of the primary reinforcement are connected with all three pillars 17, 18, 28.

Vertical connection devices 16, 20 and horizontal connection devices may be arranged in either all three pillars 17, 18, 28 or only in the first pillar 17 and the second pillar 18.

The invention is not limited to the above described embodiments. A man skilled in the art may modify the above described embodiments in many ways without departing from the scope of the invention which is limited only by the appended claims.