EP2610418A1

EP2610418A1 - Method for renovating a building and a building

Info

Publication number: EP2610418A1
Application number: EP11195780.9A
Authority: EP
Inventors: Ari Saarinen; Mikko Ilvonen
Original assignee: Neapo Oy
Current assignee: Neapo Oy
Priority date: 2011-12-27
Filing date: 2011-12-27
Publication date: 2013-07-03

Abstract

The invention relates to a method for renovating an original building positioned on an original first foundation (1), which method comprises at least the steps of forming a new second foundation (4) adjacent to the original first foundation (1), on the outside of the original building, and arranging a wall cover on said new foundation (4) to cover at least some of the original walls of the original building, the wall cover comprising wall elements (5) and extending at least up to the level of the uppermost ceiling of the original building. The method may also comprise the additional step of adding storeys to the building. Preferably, the wall elements and additional storeys are made of metallic cellular board.

Description

TECHNICAL FIELD OF THE INVENTION

The invention relates to a method for renovating a building and a building. The invention especially relates to a method of renovating a multi-storey residential building.

PRIOR ART

Buildings should typically be renovated after 30-40 years from when they are built. In Finland the buildings produced in the quantitative peak years of apartment building, the 1960's and 1970's, will be renovated in the next few years. The main part of these buildings are multi-storey prefabricated houses situated in the suburbs. They are sometimes outdated both in their structure and design, and do not as such meet present-day living requirements. The aging of the population in the next few years adds even more to the need to modernise living solutions. The renovating of prefabricated houses designed and constructed in the 60's and 70's to better meet present-day needs and the wishes of the residents can become unreasonably expensive or even be impossible to start with.
Prefabricated houses can be renovated with known renovation methods for example with a façade renovation, by renewing the insulation of the building, by building elevators, by renewing the ventilation systems, etc. In this type of renovation the building costs typically rise close to the costs of new construction. Further such a renovation can not always modernise a building to meet actual needs or wishes of the residents. Alternatively the problem has been solved by demolishing the old building entirely and building a new building on the site along with the foundations. Such solutions are expensive. Additionally a temporary placement for the residents is needed for the duration of the building work.

OBJECT AND SUMMARY OF THE INVENTION

It is an object of the present invention is to reduce or even eliminate the above-mentioned problems appearing in prior art.
It is an object of the present invention to provide a quick and cost-efficient solution to the renovation of buildings.
It is another object of the present invention to provide a solution, which makes possible the combining of old foundations and possible basement spaces with completely new residential storeys.
It is still an object of the present invention to provide a solution, which decreases the inconvenience caused to residents, users and owners of the building to be renovated.
In order to realise the objects mentioned above, among other things, the method and the building according to the invention are characterised by what is presented in the characterising parts of the enclosed independent claims.
A typical method for renovating an original building positioned on an original first foundation comprises at least the steps of

forming a new second foundation adjacent to the original first foundation, on the outside of the original building, and
arranging a wall cover on said new foundation to cover at least some of the original walls of the original building, the wall cover comprising wall elements and extending at least up to the level of the uppermost ceiling of the original building.

A typical building according to the invention has been renovated with the method according to the invention. The building thus comprises

an original first foundation, and vertical original walls arranged on the first foundation,
a new second foundation arranged adjacent to the original first foundation, on the outside of the original building, and
a wall cover arranged on said new second foundation parallel with the original walls and covering at least some of the original walls, which wall cover comprises wall elements.

In this context, a room module refers to a self-bearing module which is used in construction and which comprises a ceiling, a floor and walls. Typically, the room module is to be moved in one piece and to be installed to its location in one piece. A room arrangement refers to a structure that is formed of several room modules, which have been attached together, such as superposed apartments of a block of flats, for example. Prefabricated refers to the fact that the ceiling, floor and walls of a room module have been connected together already prior to its installation to its location in a building. Interior decoration of a prefabricated room, such as furniture, carpets, wall papers, bathroom decoration, and heating, plumbing, ventilation and electrical installations, can also be worked as readily as possible before the room module is transferred to its installation location. Moreover, a load-bearing structure refers to a structure, which carries its own weight as well as the weight above it. A typical load-bearing structure forms a support frame for the entire structure, which support frame carries forces directed to the structure, and provides sufficient functional rigidity. Renovating means repair work, for example the renovation of a building.
A typical method for renovating an original building positioned on an original first foundation comprises at least the steps of

The present invention therefore provides a method for renovating a building that is cost effective, yet gives an esthetic end result. It also enables to improve the building's heat efficiency by adding insulation and to update the building services as will be explained in more detail below.
The new wall cover that is made of one or more wall elements typically extends up to the uppermost ceiling of the building, that is, it extends at least up to the eaves of the building. The new wall cover can cover partly or fully one, two, three, four or more of the walls of the building. Preferably, the new wall cover covers parallel walls on either side of the building.
On the other hand, the wall cover is made or one or more wall elements. The size and thus number of the wall elements can be selected either based on esthetic grounds or based on practical grounds such as a size that is easy to transport.
The foundation to be made can for example be mainly concrete or masoned from stone. The storeys of the original building, which are on top of the foundations and/or basement, can be for example mainly concrete, wood, steel, or masoned such as stone or brick. The new second foundation is preferably anchored to the original first foundation, to prevent any movement relative to the original foundation. As all constructions typically subside slightly in the first years, the anchoring is preferably made in a manner that allows a small vertical movement of the new foundation with respect to the original foundation. The movement is however in the order of millimetres, or even less.
The roof of the original building can be either maintained or replaced. In case it is replaced, it can be made supported by the new wall elements. The present invention thus gives an especial advantage for the renovation of building that suffer from subsidence. Typically, this problem has been solved by adding piling underneath the original first foundation. This is however costly and quite uncomfortable for the inhabitants of the building. By adding a new second foundation that can, if deemed necessary, be based on piling, and by making the new roof supported by the new wall elements, weight can be taken away from the original foundation. Additionally, the stress caused by wind and snow is taken away from the original first foundation.
According to an embodiment, the method comprises a further step of arranging at least one vertical structure between adjacent wall elements of the wall cover. According to a preferred embodiment, the vertical structure is a pillar. This step is typically performed between the making of the new second foundation and the arrangement of the wall elements. The pillars can be either covered by the wall elements or they can be left apparent. If they are left apparent, they can be later covered with mortar, wood or any other material that is used for the outside of the building. The supporting pillars can be used if heavy loads are expected to be exerced on the roof, such as snow. They can also be used in case the building does for example not need additional heat insulation, therefore not requiring thick wall elements. In such a case, the pillars take at least part of the load of the new roof and possible new storeys that are added to the building, as is explained below.
According to a yet another embodiment, the method further comprises the steps of

arranging supporting beams on top of the uppermost ceiling of the original building, parallel to said ceiling, said supporting beams being supported by the wall elements,
arranging at least one first room module on said supporting beams to form a first additional storey, and
arranging a new roof on said additional storey.

The supporting beams form a system of beams that support one or more additional storeys. The number of beams is chosen according to the size of the building's surface area. Typically beams are arranged at a distance of 300-15000 mm from each other, and there is thus typically 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 or more individual beams. The beams are typically arranged in only one direction and parallel to each other, but it is naturally possible to form a grid of beams, too. The beams can be made of any suitable material, such as steel. According to this embodiment, the original roof of the building is removed, unless it has been a flat roof that can be left in place if desired, and a system of supporting beams is arranged on top of the uppermost ceiling of the original building. Preferably, a small gap is left between the original uppermost ceiling and the new beam system, such as 10-100 mm. This additional space firstly increases the sound proofing and secondly it is a safety margin, should the new wall elements and the new additional storeys subside slightly during the first years.
The supporting beams and the system of supporting beams are supported by the wall elements. This can be achieved either in such a manner that the beams extend over the original building's outer walls and their ends are arranged on top of the upper ends of the wall elements. Preferably the ends are then attached to each other in any suitable manner such as bolts or welding. Another option is to arrange a supporting element that is at its first end attached to the upper end of the wall element and at its second end to a supporting beam.
The supporting beams and the system of supporting beams can also or instead be supported by the pillars, if such pillars are used. In such a case, the system of supporting beams can also comprise beams that are parallel to the outer walls of the building, to form a continuous frame for the additional storeys.
The supporting beams can, according to yet another embodiment, be supported by the original building's load bearing walls, if the walls and the original foundation permits this.
The room module may for example be an apartment, a hotel room, a room in an office building or a room in some other building. The room module may for example be a conventional apartment or a row house apartment, for example a one-room, two-room or three-room apartment. There can alternatively be several apartments in a room module, for example 2-3 or 2-4 apartments, which can be moved in one piece and installed in its location in one piece. The room arrangement according can have, for example, exactly or at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40 or 50 room modules on top of each other. The room arrangement according may also have, for example, 2-10, 2-15, 2-20, 2-30, 2-40, 2-50, 3-10, 3-15, 3-20, 3-30, 3-40, 3-50, 4-10, 4-15, 4-20, 4-30, 4-40, 4-50, 5-10, 5-15, 5-20, 5-30, 5-40 or 5-50 room modules on top of each other.
The width of a typical room module can be for example 2-15 meters, 3-10 meters or 5-10 meters. The length of a typical room module can be for example 2-30 meters, 5-22 meters, 9-15 meters. The height of one room module is typically such that it suits for human residential use, typically 2-3 m. A typical room module can for example have the shape of a rectangle. The outer wall of a room module can be for example even or meandering.
It is possible that all the walls of the room module, including the separating walls, are load-bearing or for example only the outer walls can be load-bearing.
According to an embodiment, room modules are fitted side by side, so that the renovated building comprises at least two room modules in one storey. According to an embodiment room modules are fitted on top of each other, so that the renovated building comprises at least two additional storeys. Room modules can be fitted on top of each other so that the renovated building comprises additionally for example exactly or at least 2, 3, 4, 5 or 6 storeys.
Room modules can for example be fitted on top of each other so that a part or all of the load-bearing walls of the room modules are arranged to be aligned. Room modules can be fitted on top of each other also so that the load-bearing walls of the room modules end up on top of each other, but at least a part of the end walls of the room modules do not end up on top of each other. Room modules can be fitted on top of each other also so that the lower storeys have more room modules than the higher ones. Thus the amount of load-bearing walls can be increased in the lower storeys.
According to an embodiment, at least a part of and possible all of the walls of the room modules are arranged to be aligned, so that the lower edge of the walls of the upper room module settles against the upper edges of the walls of the lower room module. Thus room modules on top of each other have the same outer measurements. This way the load-bearing walls with cellular board structure are in alignment, and a structure with a good load-bearing capacity in the vertical direction is achieved.
According to one embodiment, the superposed and/or contiguous room modules are connected to each other vertically and/or horizontally. Thus, according to an embodiment, the room modules on top of each other and/or side by side are attached to each other with attaching means. The attaching means can comprise for example bolts and/or some connecting element such as a connecting profile or even several connecting elements. The walls of the room modules and the connecting elements can also be attached to each other for example by welding.
According to an embodiment, room modules, which are on top of each other, are attached together by their aligned walls with attaching means, which comprise a connecting profile, which has a first shape, which fits the upper edge of the wall of the lower room module, and a second shape, which fits the lower edge of the wall of the upper room module, which walls are to be fitted in an aligned manner, and a part which joins the first and the second shape. Such shapes that fit walls, such as a U-shaped profile, are easy to manufacture so that the connection will be firm but at the same time such that the walls are easily attached thereto.
In one embodiment, at least two room modules are attached together with attaching means, which comprise a connecting profile having shapes that fit the upper edges and/or lower edges of the walls of the room modules to be set adjacent to each other, as well as a part connecting these shapes. By joining room modules together in the horizontal direction with attaching means, which comprise a connecting profile, even high adjacent towers formed of room modules can be made more solid.
Document EP 2151376 discloses a method of arranging room modules next and on top of each other and its contents are hereby incorporated by reference, especially the embodiments shown in Figures 3, 4, 5 and 6. Moreover, also other solutions proposed by the present Applicant to attach the room modules to each other can be used, such as those disclosed in EP 2246493 , especially the embodiments shown in Figures 1, 2 and 3, as well as in FI 20115963 and FI 20115964 .
The above-mentioned connecting profiles can be made of some suitable material, such as steel, so that they are slightly flexible. Thus even high room arrangements can achieve better resistance to vibrations and bending. The connecting profiles can when necessary be joined together, for example by welding. The connecting profile be manufactured for example from 2-4 mm thick steel. The walls of the room modules can be attached to the connecting profile for example by welding, gluing or with bolts.
By increasing the number of storeys, for example the number of apartments, hotel rooms or office spaces in the building can be increased or larger apartments, hotel rooms or office spaces can be arranged in the building than in the original building. The income from the quantitative increase or the surface area increase in the apartments, hotel rooms or office spaces can for example cover the renovation costs.
According to an embodiment, the room module used in the invention is prefabricated elsewhere than at the renovation site. Thus the room module can always be built in good conditions, for example indoors. The prefabrication decreases the amount of necessary work at the renovation site, making the renovation work quicker. The interior design of the room module can also be completed before the room module is brought near the building to be renovated. Typically, the walls, floor and ceiling of the room module have the necessary number of openings for wires, cables, ducts, pipes etc. An advantage with this procedure is that the room modules and their interior design can be made already before the renovating is begun at the building site of the room module and the renovation of the building is made even quicker.
A further advantage is that a completely readily prefabricated room module can be stored even outdoors and even in frosty weather because they are closed structures. It is possible to install heating into the room module for the time of storage, or to use during storage a heating device that has possibly been installed into the room module. This way the furniture and rugs, for example, of the room module are maintained in good condition.
An outer wall of a building may directly be formed of the outer wall of the room modules. At least those structures of a room module that are intended to be outer surfaces, for example a balcony floor and an outer surface of the outer wall, may be fabricated of stainless or acid-proof steel plate, or they can be coated with the same. This way resistance to corrosion is improved. Advantageously, at least the outer surfaces of cellular board or floor cellular board, that is the surface plate of the side exposed to outdoor air, for example, are stainless or acid-proof steel. When the cells are made of stainless or acid-proof steel, they are maintenance-free and last significantly longer than other solutions.
It follows from the above advantages that the present invention, in its embodiment where additional storeys are added to the building, there is a clear synergistic effect. Indeed, by using the present method, it is possible to finance the renovation of the building by adding new apartments or rooms that can then be either sold or rented to cover the costs of the renovation.
It is also to be noted that the prior art methods of adding storeys to an original building are based on simply adding pillars on the outside of the building to support the additional storeys. The present method thus provides a more esthetic way of adding storeys, as the wall elements can be made to look identical to the original walls, whereby the appearance of the building does not chance with this respect.
According to yet a further embodiment, the method comprises, as has been partly explained above, consequently, one or more of the combination of steps of

arranging at least one second room module on a previous additional storey to form a further additional storey, and
connecting the thus superposed room modules to each other.

The method thus comprises the steps of adding more than one additional storey to the original building, each new additional storey being arranged on the previous additional storey. The number of additional storeys can be freely chosen to be for example 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or more.
According to one embodiment, the method comprises the step of connecting the wall elements to the original walls of the original building. The connecting can be made by any suitable way, such as by bolting. Preferably, the connecting is made in such a manner that the new wall elements are allowed to move slightly with respect to the original wall. This can be achieved for example with a bolt which other end is arranged to a special nut having a slit for vertical movement.
According to the present invention, when parts or elements are connected to each other, the connection can be made such that it allows small respective movements.
The openings in the wall elements for the original windows, doors and ventilations are typically sealed with a flexible seal that allows also a slight movement of a few millimetres. Such type of sealing is known to a person skilled in the art.
The walls of a typical room module can be manufactured for example from metal or wood. The walls of the room module can for example be mainly manufactured from steel, stainless steel or aluminium.
According to an embodiment, the wall elements are manufactured of cellular board. According to another embodiment, the floor, ceiling and at least two walls of the room module are manufactured at least mainly of cellular board.
According to an embodiment, at least one room module is thus made at least mainly of cellular board. Thus the floor, ceiling and at least two walls of each room module are manufactured at least mainly of cellular board. The cellular board can for example be mainly steel, stainless steel, zinc coated steel, aluminium or steel or aluminium coated with a PVC sheet. According to one embodiment, the load-bearing structures of the room module are at least mainly of cellular board.
In this application, cellular board means a structure formed of two substantially parallel surface plates and of a plate-like core arranged between them. The shape of the plate-like core is arranged to deviate from the direction of the surface plates, for example by forming folds in the plate material and grooves in between the folds. Cellular board resists bending in a transversal direction in relation to the direction of the cores especially well. Typically the core of the cellular board has been firmly attached to the surface plates. By means of a cellular board structure, it is possible to achieve a structure that is considerably lighter, more rigid and has better bending resistance than a continuous plate structure. The shape of the core has a great impact on the rigidity and strength of the cellular board. The core can for example have the shape of a wavelike bent plate, where the wave crests are typically welded to the surface plates. The cores can also be arranged for example in the shape of a letter V, or formed of plates substantially perpendicular to the surface plates, i.e. of plates that are arranged in the shape of a letter I. The core can consist of a plate bent in the form of a honeycomb. It is also possible to use beams that have the shape of a pipe, the cross-section of which is circular or another shape, as a core. In an embodiment the surface plates and the core of the cellular board are of the same material.
According to an embodiment, the cellular board is manufactured from individual profiles, by joining several profiles side by side. The profiles are manufactured from a plate-like material, which can be for example steel or aluminium. The plate-like material can on its one or both sides be coated, for example with a PVC sheet. The thickness of the plate-like material can for example be 0.5-5 mm or 0.5-3 mm.
According to an embodiment, each individual profile is meant to form in the completed cellular board a planar first surface protrusion, a planar second surface protrusion or a core, which is arranged to join the first and the second surface protrusion together. The profiles of the cellular boards are attached together so that the first surface protrusions are side by side and form the first surface plate of the cellular board, the second surface protrusions are side by side and form the second surface plate of the cellular board, and the cores of the profiles are attached to the first and second surface protrusions, whereby they make up the core structure of the cellular board. The length of the profiles can in the so-called core direction be for example 0.5-20.0 m or 1.0-10.0 m. The width of an individual profile can be for example 0.1-1.0 m, 0.1-0.5 m or 0.1-0.2 m. The thickness of a completed cellular board can be for example 0.1-1.0 m, 0.1-0.5 m or 0.1-0.2 m. A completed cellular board can have for example 5-1000, 10-200 or 20-100 profiles joined beside each other. Generally the length i.e. size of the completed cellular board is approximately the same in the direction which bears more load as the length of the profiles in the so-called core direction. The width of the cellular board in the direction, which is perpendicular to the core direction, can be for example 0.5-50 m, 1-25 m or 5-20 m. In an advantageous embodiment the direction of the cores of the cellular boards, which make up the walls of the completed room module and building, is arranged to be vertical.
In an embodiment, attaching folds which fit into each other, have been formed in the edges of the profiles which are to be joined with other profiles. Typically an attaching fold of a profile, which forms the core of a cellular board, has also been arranged to fit in connection with the attaching folds of two adjacent surface protrusions. The attaching folds can be formed so that the attaching folds formed in the ends of three separate profiles in one contact point can be attached to each other. The attaching is easy to perform for example by pressure seaming in a way known as such. Before the pressure seaming or after it, a seam insulating substance, such as a mineral wool sheet or glue, for example urethane glue, can be arranged between the profiles of the cellular board.
In an embodiment, the floor, ceiling and at least two walls of the room module are manufactured at least mainly from the cellular board as described in document WO 2007/054608 .
In one embodiment, the horizontal elements of the room modules, i.e. the ceiling or floor elements, are attached so that there will be no horizontal floor or ceiling element between two superposed vertical wall elements. In other words, the ceiling and/or the floor of a room module have thus been attached to the vertical sides of the load-bearing walls. Therefore, the ceiling and floor elements can be connected to the interior surfaces of the vertical wall elements by bolting or welding, for example. Thus, the floor element does not have to carry the weight of the room modules above it. With this solution, acoustic and thermal bridges will not be formed in the vertical walls at the location of the floor element.
Means for attaching insulation material can be attached to the surface plate of the cellular board intended to be the outer surface of a room module. For example, spikes, in which an insulation material plate can be placed, may be welded to this surface plate. For example, in a building, for example a plastering or other coating may be arranged on the insulation material plate. This way the outer wall is made as desired in regard to looks and properties, such as weather proofness, for example.
In one embodiment, insulation material, such as blow wool, may be arranged inside the cellular board that forms the wall, floor or ceiling of a room module, in a space between its core and the surface plates. Thus, the heat and sound insulation capacity is improved. The cellular board structure may be even totally filled with insulation material.
According to a preferred embodiment, at least the outer walls and preferably also the inner walls, especially the walls forming separation between different apartments, are thus insulated. On the outer walls, this increases the total insulation of the building, thus increasing its energy efficiency. On the inner walls, this improves their sound proofing.
According to one embodiment, the pipes and wires necessary for the building services are arranged in the new wall elements or between the original wall and the new wall elements. This way, it is possible both to replace the existing systems and to update them to today's standards. Building services includes heating, ventilating and air conditioning, water piping (fresh water and drainage), electricity and other energy supply, IT-network, security and alarm systems as well as fire detection and protection. By incorporating these in the new wall elements, there is no need to do extensive repair work in the original building, which has the advantages of being less of nuisance to the inhabitants and to be more cost effective.
One advantage of the invention is that acoustic and refractory insulation of the room modules is easily made. Acoustic and thermal bridges are easily cut in both vertical and horizontal directions between each room modules. A fire classification of class E can be simply achieved for the buildings according to the invention.
Due to its layer structure, for example the walls, ceilings or floors of the spaces with structures of steel cellular boards can be built as fire separating whenever necessary.
A balcony can be arranged in connection with one or several walls of the room module. This way, the building can be further updated. At the same time, an elevator can be added to the building, either completely or partially inside the building, or outside the building, for example as disclosed in Finnish utility model registration FI U7374 . Other necessary spaces, such as stairwells, possible engineering and utility service rooms etc., can be solved with modules outside or inside of the original building.
When a balcony is arranged in the addition storeys, the room module floor can continue as the floor of a balcony or a corridor or of other exterior space, and can thus can be made as a self-bearing protruding part without supporting structures. Typically, the core direction of the cellular board has then been arranged mainly perpendicular compared to the direction of the wall dividing said room. Thus, for example, the part of cellular board serving as the balcony floor does not require supporting beams or other specific load-bearing structures, such as walls supporting it from below. The direction of the cells in the walls of a room module is typically mainly vertical for achieving maximal vertical strength. Directions of the cells may also vary in some parts of the walls, floor or ceiling.
The present invention also relates to a building renovated with a method according to the present invention. A typical building according to the present invention thus comprises

According to one embodiment, vertical support structures are arranged between the adjacent wall elements of the wall cover. The other embodiments and variants presented above apply mutatis mutandis to the building according to this invention.
The invention yet further relates to wall elements made of metallic cellular board for use in the method of the invention. The invention also relates to the use of metallic cellular board as wall elements in a renovation method for buildings.
The embodiments and advantages mentioned in the text relate, in applicable parts, both to the method, the building renovated with the method and the use according to the invention, and to other embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWING

The invention is described in more detail below with reference to the enclosed schematic drawing, in which

Figure 1 shows a building renovated with a method according to a first embodiment of the invention.
Figure 2 shows a building in the process of being renovated according to a second embodiment of the invention.
Figure 3 shows one embodiment for the arrangement of a supporting beam.
Figure 4 shows a building in the process of being renovated according to a third embodiment of the invention.
Figure 5 shows one embodiment for the pillars.
Figures 6a and 6b show a building renovated with the method according to the invention.

DETAILED DESCRIPTION OF THE DRAWING

Figure 1 shows a building renovated with a method according to a first embodiment of the invention, as a side-view. In this embodiment, the original first foundation 1 supports the original walls 2 that in turn support the original roof 3, the original building having three storeys (intermediate floors being shown with dashed line 7). Adjacent to the original first foundation 1 has been arranged a new second foundation 4. On this new second foundation 4 has been arranged new wall elements 5, that cover the entire walls 2 of the original building. There has also been left an air space 6 between the original walls 2 and the new wall elements 5, this space being deliberately exaggerated for sake of clarity of the drawing. The air space 6 could also be filled with additional insulation material to further improve the insulation of the building.
Figure 2 shows a building in the process of being renovated according to a second embodiment of the invention, as a side-view. The same reference numbers are used as in Figure 1, for sake of clarity. In this embodiment, the original roof has been removed and a system of beams 7 arranged on top of the uppermost ceiling of the original building. There has also been left a small gap between the uppermost ceiling and the beams 7, although this is not shown in this schematic drawing.
The beams 7 rest, at their respective ends, on the top of the wall elements 5, and are thus supported by these wall elements. On top of the beams 7, a new storey 8 has been arranged, comprising two apartments, 8a and 8b.
Figure 3 shows one embodiment for the arrangement of a supporting beam. In this embodiment, instead of the end of the beam 7 being arranged on top of the wall element 5, a connecting element 9 is used. The connecting element has been fastened to the wall element 5 as well as to the beam 7.
Figure 4 shows a building in the process of being renovated according to a third embodiment of the invention, as a top-view. The drawing depicts the positioning of the beams 7, which can be positioned either regularly or irregularly on the top of the original building. The positioning of the beams can depend for example on the position of the original building's load bearing walls, of the position of windows in the outer walls and/or of the position of the supporting pillars added to the outside of the original building.
Figure 5 shows one embodiment for the pillars. In this embodiment, pillars 10 are arranged at both sides of a window 11, and their outer surface is at the same level as the outer surface of the wall elements 5.
Figures 6a and 6b show a building renovated with the method according to the invention. In Figure 6a, a flat-roofed original building is shown. Figure 6b shows the building as renovated with the present method. Two storeys 12 have been added, as well as a new roof 13. A new extension 14 has been added at the front of the building, housing a new staircase, the original staircase being replaced with an elevator.
The Figures show only one a few embodiments according to the invention. Facts of secondary importance regarding the main idea of the invention, facts known as such or apparent for a person skilled in the art, such as support structures possibly required by the invention, are not separately shown in the Figures. It is apparent to a person skilled in the art that the invention is not limited exclusively to the examples presented above, but that the invention can vary within the scope of the claims presented below. The dependent claims present some possible embodiments of the invention, and they are not to be considered to restrict the scope of protection of the invention as such.

Claims

A method for renovating an original building positioned on an original first foundation (1), which method comprises at least the steps of
- forming a new second foundation (4) adjacent to the original first foundation (1), on the outside of the original building, and

- arranging a wall cover on said new foundation (4) to cover at least some of the original walls of the original building, the wall cover comprising wall elements (5) and extending at least up to the level of the uppermost ceiling of the original building.
The method according to claim 1, characterised in that it further comprises the step of arranging at least one vertical structure between adjacent wall elements of the wall cover (5).
The method according to claim 2, characterised in that said vertical structure is a pillar (10).
The method according to any of the previous claims, characterised in that it further comprises the steps of
- arranging supporting beams (7) on top of the uppermost ceiling of the original building, parallel to said ceiling, said supporting beams (7) being supported by the wall elements (5),

- arranging at least one first room module (8) on said supporting beams (7) to form a first additional storey (12), and

- arranging a new roof (13) on said additional storey.
The method according to any of the previous claims, characterised in that it further comprises, consequently, one or more of the combination of steps of
- arranging at least one second or subsequent room module (8) on a first or previous additional storey to form a further additional storey, and

- connecting the thus superposed room modules to each other.
The method according to claim 4 or 5, characterised in that the contiguous and/or superposed room modules are connected to each other vertically and/or horizontally.
The method according to any of the previous claims, characterised in that it comprises the step of connecting the wall elements (5) to the original walls of the original building.
The method according to any of the previous claims, characterised in that new second foundation is anchored to the original first foundation.
The method according to claim 7 or 8, characterised in that the connection is made such that it allows respective movements in the order of millimetres.
The method according to any of the previous claims, characterised in that the wall elements (5) are manufactured of cellular board.
The method according to any of the previous claims, characterised in that the floor, ceiling and at least two walls of the room module (8) are manufactured at least mainly of cellular board.
The method according to any of the previous claims, characterised in that building services are arranged in the new wall elements or between the original wall and the new wall elements.
A building comprising
- an original first foundation (1), and vertical original walls arranged on the first foundation (1),

- a new second foundation (4) arranged adjacent to the original first foundation (1), on the outside of the original building, and

- a wall cover arranged on said new second foundation (4) parallel with the original walls and covering at least some of the original walls, which wall cover comprises wall elements (5).
The building according to claim 13, characterised in that vertical support structures are arranged between the adjacent wall elements of the wall cover.
Use of wall elements made of metallic cellular board in the method according to any of the claims 1-12 or building according to any of the claims 13-14.