The present invention relates to a building block for a building construction, where a number of building blocks put together form a wall or the like, comprising a rectangular, precast building block, as the building block comprises an outer surface layer on each side and an intermediate, insulating middle layer of corresponding material with a lower density than the surface layers, and that the building block comprises at least one vertical channel arranged to receive at least one locking plug and/or reinforced concrete.

The present invention is a new product for construction of insulated outer walls, primarily for dwelling houses, but can, of course, also be used for industrial buildings and other building constructions. The product is specifically developed to simplify house building and reduce costs, but at the same time is qualitatively as good as any product on the market today.

There are a number of building blocks on the market today. These can be divided into some main categories: Concrete blocks, lightweight blocks, insulation blocks and hybrids. Pure concrete blocks are partially used as hollow stacking blocks. These can be stacked without mortar between them, thereafter reinforced concrete is filled into the hollow spaces. Walls built in this way are inaccurate in their form and are non-insulated. They are preferably used as supporting walls.

Lightweight blocks are laid in a traditional way with mortar, and are very popular as foundation wall material for dwelling houses and as walls in frame constructions. Leca™ is a typical product in this category. Such blocks are also made as hybrids. Leca™ has such a product where a disc structure is made with the usual material on each parallel wall surface and with a core of polyurethane foam. This gives a 300 millimetre thick wall that is completely insulated with regard to the strictest Norwegian regulations. Such a solution is not used much, as much effort is required for the insulation in the mortar layers. Pure insulation blocks are a product where one casts EPS blocks in a factory. These can be stacked to a certain height and thereafter be filled with reinforced concrete. Thereafter it is necessary to polish both sides to achieve a firm wall. These are also used relatively rarely. All these block types have their advantages and disadvantages. The aim of the invention is to develop a product that combines the best in all the other products.

Primarily, there are four main aims behind the product which has been developed: simple and easy to lay, extremely even surfaces after laying, high insulation capacity and fire safe. It is a further aim to add secondary characteristics. The material shall also have good characteristics for insertion of screws, something that optimises for both nailing and screwing.

The wall will be horizontally open to diffusion, but the blocks can however be sealed with a silicone spray such that they are diffusion tight vertically. No other product in today's market seems to have this combination of characteristics.

It is a further long term aim to be able to build walls with the help of robots. The starting point will be a construction programme for all deliveries of the system according to the invention. The construction programme will be developed in parallel with the detailed development of the product and production. Here, architect drawings will be converted to construction drawings, material lists and delivery documentation.

From prior art, attention shall be given to Fl 25045, US 5,002,620, DE 32 36 187 A1 and Norwegian Application NO 2000 5692. All the documents concern building blocks for a building construction where a number of building blocks are intended to be put together to form a wall or the like and where the building block is a rectangular, precast block.

Short description of the invention The building elements according to the invention preferably comprise EPS balls with cement as a binding agent. This is a well-known product which is produced in several locations in the world. The present product has some additional materials that offer extra toughness in casting and in use. These are also known materials. What is special about the present invention lies in the shape, composition and production of the blocks.

The material that is used has different densities in the cross-section of the blocks. The building element according to the invention can have two surface layers, each one with a thickness of, for example, 20 millimetres, which preferably has the highest density. This provides the necessary strength requirements for a completed wall. A middle layer can have a low density. This provides the necessary insulating characteristic. Both layers can be optimised further in the subsequent development of the product. No information is

available about others that use different densities of this material in the same product. The dimensions of the block can, for example, be 300 x 300 x 599 millimetres. The length can possibly be somewhat adjusted later, where all the surfaces are plane. Furthermore, vertical openings are provided in the blocks, for example, a circular opening of 120 millimetres diameter in the centre and two corresponding semi-circular openings at each end. This provides circular, vertical hollow spaces of 300 millimetres vertical distance when the blocks are laid in a course. The internal surfaces of the blocks can be sealed during production with silicone spray or the like. This is to protect the insulation layer against careless handling and against ingress of water during laying when it is raining. This will also ensure the guiding holes against unwanted wear during laying. In addition this will give diffusion tightness in two directions of the wall. The external surfaces will initially not be sprayed so that the blocks can be open to diffusion across the wall.

During building, every other hole can be plugged with a locking plug, of a material that corresponds to the insulating material. This give a stable wall in the initial phases of construction. At the same time the blocks are locked in a completely accurate position in relation to the other blocks. This gives an approximately smooth wall surface. Every other hole is preferably filled with reinforced concrete to give the wall large load bearing strength. The function of the locking plug must be seen in connection with the production method for the blocks that will give the blocks the exact same dimensions, straight surfaces and right angles. The blocks are therefore locked exactly in relation to each other and the completed wall will be of a very high quality. The function of the locking plug, together with the possibilities of good tolerance in its method of production, are one of the most central parts of the new development.

All material thicknesses are initially of standard dimensions, but can be adjusted according to the wishes of the customer.

The plugs are in the main comprised of the same materials as the blocks. The plugs can be somewhat pointed at one end and thereafter get a special surface treatment to increase the thickness and to withstand the mechanical strain during laying. In production of the blocks, excess material can be recirculated. Besides, there can be an opportunity to use recirculated isopor from other sources optimally, to a smaller and larger extent.

The above mentioned aims are achieved with a building block which is characterised by the characteristics in the independent claim 1 , in that the building block is manufactured from EPS balls with cement as a binding agent and that said vertical channel(s) is formed as a through-going, circular opening between the end surfaces of the block and/or a semi-circular groove on at least one end of the block, whereby a circular opening is formed between two adjoining building blocks, as a number of said vertical channels in the building block are arranged to receive respective locking plugs formed at least partially from the same material as the building blocks.

Preferred alternative embodiments are characterised by the dependent claims 2-8. The through-going, circular opening between the end surfaces of the block is preferably arranged centrally in the block and the block comprises a semicircular grove on each end of the block.

One or more of the internal surfaces of the building block can comprise a sealant such as silicone.

A top block can comprise a horizontal, mainly U-shaped duct that runs in the longitudinal direction in an upper part of the building block. A corner block can comprise a through-going opening and only one semi-circular groove at one end, and the other end can comprise an outer surface layer.

A specific embodiment of the building block can be formed with the dimensions 300 mm x 300 mm x 599 mm, where the surface layers are formed with a thickness of 20 mm and the channels are formed with a diameter corresponding to 120 mm.

In the main, the vertical channels run through the building construction centrally in the building blocks and between the building blocks, and a selection of vertical channels can be filled with reinforced concrete, preferably every other channel.

A locking plug is preferably formed in a circular-cylindrical shape or in a semi circular-cylindrical shape.

The invention shall now be described in more detail with reference to the enclosed figures, in which:

Figure 1 shows a perspective drawing of a general building block according to the invention.

Figure 2 shows a perspective drawing of a top block according to the invention. Figure 3 shows a perspective drawing of two end blocks put together to form a corner according to the invention.

Figure 4 shows a perspective drawing of parts of a building construction according to the invention.

Figure 5 shows correspondingly a perspective drawing of parts of a building construction according to the invention.

Figure 6 shows a transparent perspective drawing of parts of a building construction according to the invention.

Figure 7 shows a perspective drawing of parts of a building construction according to the invention. Figure 8 shows correspondingly a perspective drawing of parts of a building construction according to the invention.

As mentioned, the invention relates to a building block 10 for use in a building construction 50, where a number of building blocks 10 placed together form, for example, a wall. The building block 10 according to the invention is in the main formed as a rectangular, completed building block and which comprises an outer surface layer 12, 14 on each side surface and an intermediate, insulating middle layer 16 of a lower density than the surface layers. Furthermore, the building block 10 comprises vertical, through-going channels 18, 20 arranged to receive at least one locking plug 60, 62 or reinforced concrete. Said channels are shaped as a through-going circular opening 18, in the main centrally in the block, and a semi circular groove 20 at each end of the block, whereby a circular opening 52 is provided between two adjoining building blocks 10.

Figure 1 shows an example of a building block 10 according to the invention. The building block according to the embodiment example is preferably formed with dimensions 300 mm x 300 mm x 599 mm, where the surface layers 12, 14 are made with a thickness of 20 mm and the through-going, central channel 18 is formed with a diameter of 120 mm. The dimensions of the side channels 20 are consequently half of the diameter of the middle channel 18, so that when two building blocks 10 are placed together, the same diameter is created in all channels. The dimensions of the building block are consequently not limited to

the above mentioned dimensions, but can be produced in the dimensions that are desired or practical.

The building block 10 is cast in its own production process, and is treated so that it has the desired shape and size. The building block 10 is preferably manufactured from EPS balls with cement as binding agent. EPS stands for expanded polystyrene, and is a petroleum product. EPS does not contain KFK/HKFK. When using EPS as building insulation material, one saves a lot of energy, and thus protects the environment. EPS does not dissolve in water or air and therefore does not pollute the environment. Fungi and bacteria can not grow on EPS. If one wishes a greater pressure strength or moisture resistance, XPS, or any other corresponding material, for example can be used completely or partially in place of EPS.

One or more of the internal surfaces of the building block 10, i.e. the channels and/or surfaces of opposite building blocks that face each other, can be comprised of a sealant such as silicone. The aim of this is to protect the insulating layer against careless handling and against ingress of water when laying when it is raining. Furthermore, the channels are also protected against unwanted wear during laying. In addition, this provides diffusion tightness in two directions of the wall. Initially, the external surfaces will not be sprayed so that the blocks can be open to diffusion across the wall, but a sealant can, of course, be applied to all surfaces if appropriate.

Figure 2 shows an example of a top block 30. The top block 30 is in the main manufactured and formed in the same way as given above, but comprises in addition a groove or duct 32 that runs in the whole or parts of the upper section of the block. The groove or duct 32 is formed so that it can be filled with armouring and concrete, or the like, and can function as a cast concrete girder. The depth of the groove or duct is adapted to the desired amount of armouring 72 and fill material 74.

Figure 3 shows two corner blocks 40 which are put together. The corner block 40 is in the main manufactured and formed in the same way as described above. However, the corner block 40 will comprise a through-going opening 18 and only one semi circular groove 20 at one end, and the other end 42 can comprise an outer surface layer corresponding to that of the side surfaces of the building block. Alternatively, the corner block can comprise a tapered end

edge, or the corner block can be formed in an L-shape. Furthermore, the corner block can be made to be shorter than said building blocks 10, and the through-going opening 18 is no longer arranged centrally in the block, but arranged so that the opening runs through the over lying and/or under lying corner blocks centrally in the corner of the building construction. The top comer blocks can be formed with a groove or duct 32 corresponding to that described for the top block.

The figures 4-8 show different examples of the building up of parts of the building construction 50. The preparation of the foundation is carried out in a known way and will not be described further. It can be seen that building blocks are placed adjoining each other so that a through-going opening 52 is provided between the channels 20 at the end of the building block. A locking plug is thereafter placed in the openings 52 and 18. The locking plugs 60 are preferably formed with a circular-cylindrical shape with the same diameter as the openings. However, a semi-circular cylindrical locking plug 62 can be used in the corner of the building construction, as shown in the figures 4 and 5. The length of the locking plugs can be corresponding to the height of the building blocks, or alternatively longer so that they run vertically through several or all the building blocks. Every other opening 18, 52 is preferably filled with concrete 70. Openings for doors and windows can be cut out after the wall has been completed, or such openings can be adapted during the fitting of the building elements.

The locking plugs are, as mentioned, preferably manufactured from the same material as the building block, and then especially of the same material as the middle layer of the building block. However, it can be necessary to harden the locking plugs by the addition of an outer surface layer, such as cement. Furthermore, it can be relevant as an alternative to manufacture the locking plugs from a different material than the building blocks if this is required or appropriate.