EP4291735A1

EP4291735A1 - Method for renovating buildings and increasing their energy efficiency

Info

Publication number: EP4291735A1
Application number: EP22716877.0A
Authority: EP
Inventors: Jens Stefan OEHLER; Detlef LENSCHEN; Willi Richard Brombacher; Emanuel HEISENBERG
Original assignee: Ecoworks GmbH
Current assignee: Ecoworks GmbH
Priority date: 2021-03-24
Filing date: 2022-03-18
Publication date: 2023-12-20
Also published as: WO2022200197A1

Abstract

The invention relates to a method for renovating buildings and increasing their energy efficiency, which includes mounting prefabricated panels in front of the outer building wall for at least partial and preferably full coverage.

Description

Method for renovatinq buildinqs and increasinq their enerqv efficiency

The invention relates to a method for renovating buildings and increasing their energy efficiency, in which at least parts of the outer building wall are covered with prefabricated panels.

Achieving carbon emission and energy consumption goals set by numerous governments will require, among other things, comprehensive renovation of existing buildings for increased energy efficiency. Ideally, renovation should be such as to enable climate-neutral operation of the buildings. Countless approaches for renovating buildings and increasing their energy efficiency have been developed and tested, but for various reasons there are still unsolved problems in implementation and the methods still lack acceptance on a significant scale.

The invention aims to provide a method for renovating buildings and increasing their energy efficiency which can be scaled up to a level of industrial serial production and support renovation of significant numbers of buildings with short assembly times and at low cost.

Against the above background, the invention relates to a method for renovating buildings and increasing their energy efficiency, which includes mounting prefabricated panels in front of the outer building wall for at least partial and preferably full coverage. The prefabricated panels comprise fagade panel elements and further comprise building service elements. The fagade panel elements are thermally insulated. There can be a single type of fagade panel element or there can be two or more types of differently configured fagade panel elements, and the fagade panel elements, or at least one type of fagade panel elements comprises one or more apertures in the format of windows or doors. The fagade elements comprising such apertures are positioned in front of the outer building wall such that the apertures align with existing apertures for windows or doors in the outer building wall. The building service elements enclose an interior room that can accommodate utility components, for example components to provide for one or more of ventilation, electricity, gas, water, sewage, or communications services with respect to a residential unit of the building. Further, the building service elements comprise a duct portion to accommodate lines extending vertically through the building service elements.

Preferably, the utility components are pre-installed in the building service elements before the building service elements are mounted in front of the outer building wall. Alternatively, it is also possible to install at least part of the utility components only after the building service elements have been mounted in front of the outer building wall.

Typically, the method comprises mounting two or more fagade panel elements on top of each other in front of the outer building wall to cover a vertical stripe section thereof. Usually, the method involves generating a number of such arrays to cover multiple vertical stripe sections of the outer building wall, and taken together cover at least a significant portion of the outer walls of the building. The entire height of the, or each, array of fagade panel elements typically corresponds to the height of the outer building wall. Within one array of vertically stacked fagade panel elements, depending on the kind of building, all fagade panel elements can be identical.

Likewise, the method typically comprises mounting two or more building service elements on top of each other in front of the outer building wall to form an array that covers another vertical stripe section thereof. Such array of vertically staggered building service elements is typically arranged adjacent to an array of vertically staggered fagade panel elements, at least on one side, in which case a different array of vertically staggered building service elements can be adjacently arranged on the other side, and in embodiments on both sides. The building service elements of such array are typically arranged on top of one another such that their duct portions are in line and form one single duct for pipes and cables extending vertically through the entire height of the array, typically corresponding to the height of the outer building wall. The thickness of all types of fagade panel elements is preferably identical, so that the transition between the individual elements on the outer building wall is flush on the outside. The thickness of the building service elements can be the same as the thickness of the fagade panel elements, but preferably the building service elements are a bit thicker than the fagade panel elements and, in turn, a gap of a few centimetres is left between the outer building wall and the inside of the fagade panel elements. This provides maximum space for utilities to be mounted inside the building service elements, while the gap behind the fagade panel elements can be used to account for tolerances in the outer building wall and to accommodate fastening elements as well as pipes and cables. Preferably, despite potential differences in thickness, the outer surface of the building envelope formed by the fagade panel elements and the building service elements, is flush. The total thickness of the building envelope, from old outer surface of the building to outer surface of the building envelope is between 15 cm and 55 cm, preferably between 20 cm and 40 cm. The exposed main surfaces of the fagade panel elements and the building service elements typically comprise uniform finishes to ensure a uniform appearance of the renovated building.

Typically, the vertical dimension of the fagade panel elements and the building service elements corresponds to the height of one floor of the building.

In one embodiment, the building has between two and five floors. The method in one embodiment is particularly suited for buildings of such height, especially when a mounting scheme as described further below is used. A significant portion of the housing stock of European cities is within that range.

Typically, the number of arrays of vertically staggered building service elements is related to the number of residential units per floor of the building. In one embodiment, one building service element is assigned to each residential unit. Thus, for example, if each floor of a building comprises two residential units, there may be two arrays of vertically staggered building service elements. The building service elements can have large or even full-surface access openings on their exposed main surfaces, which are covered by suitable closure elements such as insulated doors or flaps. This facilitates easy access to the ducts and utility components from the outside for installation, maintenance, etc.

The utility components within the building service elements may be selected such that a part or all of the ventilation, electricity, gas, water, sewage, or communications services of one residential unit of the building can be handled by the utility components of the building service elements. For example, the utility components mounted inside the building service elements can comprise one or more components selected from a ventilation and exhaust system, a heat recovery system, a supply or exhaust air fan, an instant water heater, a hot water tank, a heat exchanger, an air filter, a heat pump like a refrigerant circuit, water consumption or electricity consumption counters, sensors, switches and circuits for electricity or data cables or valves for air or water lines.

Cables for electricity or data, and tubes for freshwater, air and sewage, at least in part run through the ducts formed by arrays of vertically stacked building service elements. At least part of the utility components inside each building service element in the array can be connected to such cables or ducts. The cables or pipes, or parts forming for the cables and pipes, can be preinstalled in the building service elements before mounting them in front of the outer building wall. Especially for electricity or data cables, subsequent installation after the building service element or elements have been mounted in front of the outer building wall is usually preferred, however.

Intake and exhaust openings for fresh air and used air, in one embodiment, are provided at each building service element, for example in the exposed main surface thereof. The connection of the utility components inside the building service elements and residential units of the building is typically facilitated by horizontally running pipes and cables through a core drilling in the outer building wall. The core drilling or core drillings are preferably located behind the building service element and run near the top and/or the bottom of the respective floor of the building.

In terms of construction, the fagade panel elements are preferably frame elements and in particular wood frame elements, which comprise an outer frame preferably formed from wooden frame elements. In addition to the outer frame, the frame elements may comprise inner frames, which can define the silhouettes of window or door apertures, and/or struts. Also the inner frames and struts are preferably formed from wooden frame elements. On the two main surfaces the frame is covered by plates. The plates can likewise be formed from wood or wood-based materials. In other embodiments, gypsum fibreboard plates may be preferred for improved fire resistance. A thermally insulating material is typically present in the cavities defined by the frame elements and the cover plates. The thermally insulating material is preferably a renewable or recycled material, and can be formed from cellulose material or wood fibers.

In one embodiment, a fagade panel element and a building service element arranged adjacent on one side thereof can be combined prior mounting to the building wall and then mounted as one integral part. In most cases it is preferred, however, that fagade panel elements and building service elements are separately mounted. In particular, it can be preferred that an array of building service elements is mounted in front of the building before fagade panel elements are mounted adjacently, because this may enable making necessary connections more easily.

In a preferred embodiment, the prefabricated panels, i.e. the fagade panel elements, the building service elements, or both are mounted in front of the outer building wall by fixing them on fastening strands that are suspended from an anchoring structure sitting on top of the outer building wall. In other words, the weight of the fastening strands and hence ultimately prefabricated panels is introduced into the outer building wall from at its top.

Suitable types of fastening strand include, for example, metal beams. The fastening strands comprise structures, for example hook contours, that allow to fix, for example bolt or hang in, fagade and building service elements, which comprise appropriate mating structures on their back side or side edges.

To maximize the space available for utility components inside the building service elements, the building service elements in one embodiment can be thicker than the fagade panel elements and there can be no gap, or little gap only as far as necessary for tolerance compensation, between the building service elements and the outer building wall, in contrast to the gap preferably present between the outer building wall and the fagade panel elements. Accordingly, the fastening strands can extend vertically along the outer building wall behind the fagade panel elements and closely beside the building service elements. Mating structures for fixing on the metal beams can hence be present at the back side of fagade panel elements and at the side edges of building service elements.

Per array of fagade and building service elements there can be two suspended metal beams, so that fagade and building service elements can be fixed to one metal beam on their left and right. In embodiments, one metal beam can be shared by adjacent fagade and building service elements.

In one embodiment, the anchoring structure sitting on top of the outer building wall is formed from foot purlins of a purlin roof of the building. Preferably, in this embodiment, the method comprises removing an existing roof of the building and setting new foot purlins after removing the existing roof, as part of a new roof, preferably purlin roof to be constructed and simultaneously as anchoring structure for the suspended mounting of the prefabricated panels in front. In another variant, existing foot purlins of the building can be used as anchoring structure for the suspended mounting of the prefabricated panels.

The construction of a new roof during the inventive method can comprise using prefabricated roof panel elements and placing them on a new or existing roof framework, preferably a purlin truss. Like the fagade panel elements, the roof panel elements are preferably of insulated wooden frame construction. For details, reference can be made to the above description of the fagade panel elements. The roof panel elements may have apertures for roof windows or the like.

In one embodiment, two roof panel elements can be pivotably connected along one common side edge. This allows transporting the connected roof panel elements in a folded position, where the roof panel elements are arranged parallel to one another, and setting them onto the roof framework in an unfolded position, where the roof panel elements stand at an angle to each other, such that the common side edges where the roof panels are pivotably connected runs along the crest line of the new roof.

In one embodiment, the roof panel elements may have photovoltaic modules pre mounted thereon before being mounted to the building, preferably in the course of industrial production. In another embodiment, photovoltaic modules can be retro-fitted to the roof panel elements after they have been mounted to the building. Inverters for the electricity produced in the photovoltaic modules are preferably located on top of the building. The distribution board for distributing the electricity, for example for connecting with the general power supply and consumers, to the contrary is preferably located in the basement of the building. Electricity cables for connecting the inverter and the distribution board can be run through the duct formed by an array of staggered building service elements.

In one embodiment, before the fagade panel elements are mounted, existing windows and doors are removed from the building at least where the outer building wall is being covered by fagade panel elements. After mounting of the fagade panel elements, lining elements can be inserted into the aligned apertures in the outer building wall and fagade panel elements to form for new reveals and cover a gap between the outer building wall and the fagade panel elements. Preferably, lining elements are inserted into the aligned apertures from the inside of the building. New windows or doors are then fitted into the lined apertures.

In one embodiment, the lining elements are equipped with heating elements, preferably electric heating elements like heating mats. The heating elements are usually located on the surface of the lining elements turned away from the aperture. This embodiment allows heating directly at weak spots in the thermal insulation of the building and can contribute to improve energy efficiency of the renovated building.

Electrical energy or, in another variant, heated fluid is typically supplied to heating elements of the lining elements, if any, by cable or pipe connection to utility components within a building service element mounted on the same floor of the building. Cables or pipes can run horizontally in a gap between fagade panel element and utility element.

In one embodiment the method further encompasses machining a narrow and essentially vertical trench, which follows the direction of the outer building wall at a certain distance of, for example, between 10 and 100 cm, into the ground, and placing insulating boards or materials, like insulating granules, inside the trench. In one embodiment, the trench is 5-30 cm, preferably 10-20 cm wide and/or 50-200 cm deep. This method can be an attractive option to improve insulation of the building also at its basement, alternative to exposing the basement wall and insulating it directly. Horizontal or oblique insulation elements like boards can be used to cover a gap between insulated trench and outer building wall.

The inventive method for renovating buildings is minimally invasive. It can be carried out while the residential units are occupied by residents, is comparatively quiet and clean, and can be completed within days. The existing building is wrapped as completely as possible on the outer building walls and, preferably, by also setting up a new roof.

Further details and advantages of the invention can be taken from the following description of working examples and figures. The figures show:

Figure 1 : a schematic illustration of a building during different stages of being renovated in accordance with the invention;

Figure 2: a sectional view of the upper part of a building renovated in accordance with the invention;

Figure 3: a sectional view of building service elements mounted in front of the outer building wall;

Figure 4: a sectional view of one of these building service elements and parts of adjacent fagade panel elements;

Figure 5: a schematic illustration showing suspended fastening strands for mounting the prefabricated panels;

Figure 6: a schematic illustration of a pair of connected roof panel elements;

Figure 7: a sectional view of the area around the top of the outer building wall and the bottom of the roof;

Figure 8: a sectional view of the envelope of a building renovated in accordance with the invention around its basement;

Figure 9: an illustration of how a trench to obtain this structure can be machined into the ground; Figure 10: an illustration of a fagade panel element during manufacture;

Figure 11 : a sectional view of a window aperture;

Figure 12: a front view of an empty building service element;

Figure 13: a front view of a building service element comprising utility components mounted therein.

Figure 1 illustrates how fagade panel elements 100 of different types 100a, 100b, 100c are arranged in vertical arrays in front of different strip-shaped sections of the outer building wall 910. Each fagade panel element 100 extends over one floor 901 or 902 of the building 900. Each type 100a, 100b, 100c of fagade panel element comprises apertures 121 , 122 for windows or doors, wherein position and size the apertures depends on the position and size of window and door apertures 921 , 922 in the covered portions of the outer building wall 910. The fagade panel elements 100 are positioned such that their apertures 121 , 122 are in line with the apertures 921 , 922 in the outer building wall 910.

Figure 2 is a sectional view of the upper part of a building 900 that has been renovated in agreement with the inventive method. Specifically, the roof framework 800 has been set up as described in more detail later, and the fagade panel elements 100 have been mounted in front of the outer building wall 910 with their apertures 121 aligned with window apertures 921 in the outer building wall 910. Base purlins 840 and suspended fastening strands 400 form the basis for the new roof framework 800 and for mounting the fagade and building service elements. The attachment of the fagade and building service elements to the suspended fastening strands 400 will be described in more detail in connection with Figure 5. Figures 3 and 4 show sectional views of building service elements 200 adjacently mounted in front of the outer building wall 910, in the case of Figure 4 with also parts of adjacently mounted fagade panel elements 100 being visible.

As it was described in the context of Figure 1 for the fagade panel elements 100, also the building service elements 200 cover a strip-shaped section of the outer building wall 910 and are attached to suspended fastening strands 400. All fagade panel elements 100 and building service elements 200 extend over one floor 901 , 902 of the building 900 in vertical direction. Each building service element 200 comprises utility components for one or more of ventilation, electricity, gas, water, sewage, or communications services with respect to a residential unit of the building 900. Arrays of vertically stacked building service elements 200 are not shown in Figure 1 , but would in each case run directly adjacent an array of fagade panel elements 100.

The number of arrays of stacked building service elements 200 may correspond to the number of residential units in each floor 901 , 902 of the building 900. Two or more arrays of building service elements 200 may run directly adjacent to each other, or one or more arrays of fagade panel elements 100 may run in between. In any case, there are no gaps between arrays of building service elements 200 and arrays of fagade panel elements 100.

The building service elements 200 comprise an interior room 220 that can accommodate utility components and comprises a duct portion 210 to accommodate lines extending vertically through the building service elements. The exposed main surface of the building service elements 200 comprise a full format access opening 230 covered with pivotable doors 231 . The access opening 230 facilitates access to the duct portion 210 and the interior room 220 that accommodates the different utility components.

The exposed front surfaces of the fagade and building service elements 100, 200 comprise matching surfaces, and the fagade and building service elements 100, 200 are mounted such that their exposed front surfaces are flush, such that the renovated building 900 has a uniform appearance.

The utility components of each building service element 200 are connected to appropriate partners, e.g. electricity consumers via lines (cables of pipes) 390 that horizontally penetrate into the residential units of the building through core drill holes 930 in the outer building wall. Preferably, lines 390 run at the ceiling of a floor of the building. For some lines, e.g. in the case of sewage lines, the lines at the ceiling of one floor of the building can service the residential unit in the floor above.

Figure 5 shows a system for mounting fagade and building service elements 100, 200 in front of the outer building wall 910. Specifically, fastening strands in the form of metal beams 400 are suspended from anchoring structures sitting on top of the outer building wall 910. Specifically, the foot purlins 840 of a purlin roof serve as anchoring structure. The foot purlins 840 may have already been present in the building before renovation and only exposed during renovation, or may have been newly set during the renovation. In addition to being suspended from the foot purlins 840, the metal beams 400 are additionally bolted to the outer building wall 910 in regular or irregular intervals, but this bolting only serves to keep them in place and as additional reinforcement. The main load is introduced to the outer building wall 910 from its top and in a vertical direction downwards, via the foot purlin 840, which has a static advantage especially in older building walls with varying material quality and hence robustness of bolts placed at different locations on the wall surface.

The metal beams 400 comprise structures, for example hook contours 410, that allow to fix, for example bolt or hang in, fagade and building service elements 100, 200, which comprise appropriate mating structures on their back side or side edges. Specifically, to maximize the space available for utility components inside the building service elements, the building service elements 200 can be thicker than the fagade panel elements 100 and there can be no gap, or little gap only as far as necessary for tolerance compensation, between the building service elements 200 and the outer building wall 910, in contrast to the gap preferably present between the outer building wall 910 and the fagade panel elements 100. Accordingly, the metal beams 400 can extend vertically along the outer building wall 910 behind the fagade panel elements 100 and closely next to the building service elements 200. Mating structures for fixing on the metal beams 400 can hence be present at the back side of fagade panel elements 100 and at the side edges of building service elements 200. Per array of fagade and building service elements 100, 200 there can be two suspended metal beams 400, so that elements 100, 200 can be fixed to one metal beam 400 on their left and right. In embodiments, one metal beam 400 can be shared by adjacent fagade and building service elements 100, 200.

Figure 6 shows a pair of roof panel elements 810 that are pivotably connected along one common side edge. Figure 7 shows sectional view of the area around the top of the outer building wall and the bottom of the roof.

The method can comprise removing an existing roof from the building 900. After removal, a new purlin roof is preferably constructed. This construction encompasses the setting of new foot purlins 840 as one of the first steps. Next to forming an anchoring structure for the metal beams 400, as explained above, the foot purlins 840 also form structural elements of a framework of a new purlin roof. Once the framework is in place, the method can comprise placing prefabricated roof panel elements 810 onto the framework.

In the embodiment shown in Figure 6, the roof panel elements 810 are pivotably connected along one common side edge through a hinge 820 and can be moved from a folded position to an open position (the left figure of Figure 6 shows a half-open position, the right figure shows an open position). In this embodiment, the pair of prefabricated panels can be transported to the construction site as a flat part, where it can be picked up by a crane, unfolded, placed onto the roof framework in an unfolded state, and fixed. This approach increases the degree of prefabrication and decreases the amount of work to be done at the construction site. Like the fagade panel elements 100, the roof panel elements 810 are preferably of insulated wooden frame construction. For details, reference can be made to the description of manufacturing the fagade panel elements 100, which is to follow at a later point in this description.

As illustrated in Figure 7, the exposed main surface of the roof panel elements 810 is covered with a weatherproof roof foil 830. Furthermore, the roof or individual roof panel elements 810 can be provided with photovoltaic modules 850 for increased energy efficiency of the renovated building. To minimize effort for implementing all necessary electronic for distributing and using the electricity generated in the photovoltaic modules 850, in one embodiment, inverters for the electricity produced in the photovoltaic modules 850 are preferably located on top of the building close to the photovoltaic modules, while the distribution board for distributing the electricity, for example for connecting with the general power supply and consumers, is located in the basement of the building 900. Electricity cables for connecting the inverter and the distribution board are run through the duct 210 formed by an array of staggered building service elements 200.

To improve insulation also around the basement of the building, a vertical trench 700 following the direction of the basement wall at a certain distance can be machined into the ground. This is schematically illustrated in Figure 8. To machine the trench 700, of a mobile trencher 770 as shown schematically in Figure 9 can be used. Insulation boards 710 are then inserted into the trench 700. Additional insulation panels 720 can be installed to cover a gap between the insulation panels 710 and the outer building wall 910 or its newly formed shell 100, 200, respectively. Compared with a procedure where soil is excavated to expose and insulate the basement wall, this represents a considerable simplification and acceleration in practical implementation.

Figure 10 shows a fagade panel element 100 during manufacture. The element 100 is of wood frame construction and comprises an outer frame 111 formed from wooden beams, several struts 112 likewise formed from wooden beams, and window frames 113 likewise formed from wooden beams. The main surfaces of the frame construction are covered by plates 121 , which are formed from gypsum fibre material. A renewable and biodegradable wood fibre insulating material is present in the cavities defined between the frame elements 111 , 112 and 113 and the cover plates 121 .

Figure 11 shows a sectional view of a fagade panel element 100 mounted in front of the outer building wall 910. The fagade panel element 100 comprises a window aperture 121 and is positioned in front of the outer building wall 921 such that the window aperture 921 in the outer building wall 921 .

Before the fagade panel element 100 is mounted, existing windows have already been removed from the window aperture 921 in the outer building wall 921 . After the fagade panel elements 100 are mounted, lining elements 600 are inserted into the aligned apertures 121 , 921 . The lining elements 600 form reveals that cover the circumferential area of the aligned apertures 121 , 921 over their entire depth and hence also cover gaps between the outer building wall 910 and the fagade panel elements 100. New energy-efficient windows and sunshades 912 are then mounted inside the aligned and lined apertures 121 , 921.

The back surfaces 610 of the lining elements 600 comprise electric heating mats 620 to provide heating right at the window and hence at a natural weak point of the building insulation. Electricity can provided to the heating mats 620 from within the building or via cables that run in the gap behind the fagade panel elements 100 and connect to utility components inside the building service element 200.

To support a more detailed description of the building service elements 200 and the utility components that may be mounted therein, Figure 12 illustrates an empty building service element 200 and Figure 13 shows the same building service element 200 with utility components and lines present. As shown in Figure 12, the building service elements 200 enclose an interior room 220 to accommodate utility components, which comprises duct portions 210a and 210b left and right of the part where the utility components are mounted.

To mount the utility components, the room 220 comprises are a plurality of compartments 221a, 221b, 221c, etc., which are formed from modular partitions that can be arranged freely on a number of instalment positions within the interior room 220. This allows using one basic design for the building service element 200 for a multitude of applications, where different utility components are required. Prefabricated openings 222 in a read wall of the building service element 200 can be used to run lines towards the building wall, which they then penetrate through core drillings as explained in more detail above.

Figure 13 illustrates an exemplary configuration of utility components inside the building service element 200. The components comprise a ventilation system 260 with heat recovery, encompassing a supply air line 261 leading into a residential unit and an exhaust air line 262 exiting from the residential unit. A condensate line 264 can dispose of condensate water. A heat pump 241 that is in thermal connection with this ventilation system is further comprised in the building service element 200. It constitutes one means to heat water inside a hot water tank 242, sized to accommodate, for example, 100-160 litres of water. Additionally, there can be an electric heating element for auxiliary heating the water in tank 242. A refrigerant circuit 263 serves as an air conditioner and optional cooling of fresh air. Water risers run vertically through duct portion 210b. They are connected to the hot water tank 242 or pass into the residential unit. A sewage line 273 runs vertically through duct portion 210a. Cables for power and signal lines are not illustrated in Figure 13, but can likewise run vertically through one of the duct portions 210a and 210b. The utility components used in the give example include all the components necessary for supplying a residential unit with hot and cold fresh air, with hot and cold water, electricity and data signals, and for removing sewage.

Claims

1. A method for renovating buildings and increasing their energy efficiency, which includes mounting prefabricated panels in front of the outer building wall for at least partial and preferably full coverage, wherein the prefabricated panels comprise thermally insulated fagade panel elements and building service elements; wherein at least a part of the fagade panel elements comprises one or more apertures and is positioned in front of the outer building wall such that the apertures align with existing apertures for windows or doors in the outer building wall; wherein the building service elements enclose an interior room that can accommodate utility components and comprises a duct portion to accommodate lines extending vertically through the building service elements.

2. The method according to claim 1 , wherein the fagade panel elements are wood frame elements, which comprise a wooden outer frame, optionally one or more wooden inner frames, and wooden struts, which are covered by plates on the two main surfaces, and which comprise thermally insulating material within the cavities defined between frame elements and plates.

3. The method according to any preceding claim, wherein the method comprises mounting two or more fagade panel elements on top of each other to form arrays that cover a vertical stripe sections of the outer building wall, and comprises mounting two or more building service elements on top of each other to form arrays that cover other vertical stripe sections of the outer building wall.

4. The method according to claim 3, wherein at least two different arrays of vertically stacked fagade panel elements comprise different types of fagade panel elements, which differ in presence, kind and position of apertures.

5. A method according to any preceding claim, wherein the building service elements are thicker than the fagade panel elements and wherein a gap between the outer building wall and the building service elements is not present or at least smaller than a gap between the outer building wall and the fagade panel elements.

6. A method according to any preceding claim, wherein the fagade panel elements and the building service elements are mounted in front of the outer building wall by fixing them on fastening strands that are suspended from an anchoring structure sitting on top of the outer building wall.

7. A method according to claim 6, wherein foot purlins of a purlin roof of the building serve as the anchoring structure.

8. A method according to claim 6 or 7, wherein the fastening strands extend vertically along the outer building wall behind the fagade panel elements and closely beside the building service elements, and wherein mating structures for fixing on the fastening strands are present at the back side of fagade panel elements and at the side edges of building service elements.

9. A method according to any preceding claim, wherein the building service elements can have large or even full-surface access openings on their exposed main surfaces, which are covered by closure elements such as insulated doors or flaps.

10. A method according to any preceding claim, wherein the vertical dimension of the fagade panel elements and the building service elements corresponds to the height of one floor of the building.

11. A method according to any preceding claim, wherein the utility components comprise one or more components selected from a ventilation and exhaust system, a heat recovery system, a supply or exhaust air fan, an instant water heater, a hot water tank, a heat exchanger, an air filter, a heat pump like a refrigerant circuit, water consumption or electricity consumption counters, sensors, switches and circuits for electricity or data cables or valves for air or water lines.

12. A method according to any preceding claim, wherein the method comprises removing an existing roof of the building, setting new foot purlins onto the outer building walls, and constructing a new roof by setting up a new roof framework and mounting prefabricated roof panel elements on the framework.

13. A method according to any preceding claim, wherein before the fagade panel elements are mounted, existing windows and doors are removed from the building at least where the outer building wall is being covered by fagade panel elements, and wherein, after mounting of the fagade panel elements, lining elements can be inserted into the aligned apertures in the outer building wall and fagade panel elements to form for new reveals and cover a gap between the outer building wall and the fagade panel elements.

14. A method according to claim 13, wherein the lining elements are equipped with heating elements, preferably electric heating mats.

15. A method according to any preceding claim, wherein a narrow and essentially vertical trench, which follows the direction of the outer building wall at a certain distance of, for example, between 10 and 100 cm, is machined into the ground, and wherein insulating boards or materials, like insulating granules, are placed inside the trench.