Patent Publication Number: US-11035119-B2

Title: Partition wall

Description:
REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. national stage application of PCT/EP2018/056952, filed Mar. 20, 2018, which claims priority from European Patent Application No. EP 17163028.8, filed Mar. 27, 2017. The entire content of each application is incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The present disclosure relates to a partition wall, more particular to a party wall for a building. 
     BACKGROUND OF THE INVENTION 
     A party wall (also called parti-wall, parting wall or also known as a common wall) is a dividing partition between two adjoining building units that is shared by the residents on each side of the wall. Such a partition wall is often required to be load-bearing and the partition wall is also required to fulfil certain building requirements. Although these may vary from country to country, very often the wall must be designed to meet established criteria for sound, in particular airborne sound, and/or fire protection between the residential units. Thus, it is required that the partition wall according to the disclosure provides outstanding airborne sound and fire insulation. 
     Besides the requirements in relation to sound and fire insulation, it is further desirable that a partition wall has as small a thickness as possible since the area of space in the two adjacent building units is reduced due to the space that the partition wall takes up. These requirements can be somewhat counteracting when designing and constructing the partition wall. 
     It is known to build the partition wall as two halves, where two base profiles are installed and two sets of vertical metal profiles are mounted thereon and with insulation material therebetween, such as shown schematically in  FIG. 1 . However, this incurs extra building costs and space as two separate wall members need to be erected and insulated. 
     From WO 2014/187726 a thermally insulating outer wall of a building structure is known. However, such wall is specifically designed for excellent thermal insulation and different claddings on the interior and exterior sides. In order to achieve the acoustic (sound) insulation, the thickness is unacceptable large for a party wall. 
     It is on this background an object of the present disclosure to provide a partition wall between two building units, which satisfies the building requirements concerning sound and fire insulation for a party wall, but also has as relatively small thickness though being load-bearing and which is cost effective in materials and labour costs when erecting the wall. 
     SUMMARY OF THE INVENTION 
     This object is achieved by a partition wall for a building structure comprising a plurality of building units separated by such partition wall to provide excellent acoustic insulation therebetween, said partition wall comprising:
         a plurality of column assemblies, such as at least two, substantially vertically mounted in a generally horizontally oriented base profile, each column assembly comprising   a central element made of mineral wool fibres and at least a first spacer elements made of mineral wool fibres and extending from said central section towards the first side with a first intermediate profile provided between the central element and the first spacer elements and a second intermediate profile provided on the side of the central element facing the second side of the wall,   a second spacer elements made of mineral wool fibres and extending towards the second side of the partition wall; and wherein the density of the mineral wool in the central element is higher than the density of the first and second spacer elements,   one or more insulation sections fitted between two adjacent column assemblies, wherein each insulation section comprises   an inner mineral wool fibre panel provided in a close fit between the central elements of said adjacent column assemblies;   first and second mineral wool fibre panels provided in a close fit between the first and second spacer elements, respectively, of said adjacent column assemblies, and wherein the densities of said first and second mineral wool fibre panels are substantially the same or lower than the density of the inner mineral wool panel; and   a first external wall cover abutting the first mineral wool fibre panel and secured to the first spacer elements of the adjacent column assemblies, and a second external wall cover abutting the second mineral wool fibre panel and secured to the second spacer elements of the adjacent column assemblies.       

     By a partition wall according to the disclosure, there is provided a load-bearing and stabilizing wall system with limited acoustic (or sound) bridges being present. Mineral wool, fibre boards are well-known for their thermal and acoustic insulating and fire retarding properties so by providing the columns assemblies of mineral wool fibres, basically all the components of the wall contribute to achieving the advantageous sound insulation. From a cost perspective it is advantageous that only a single row of the column assemblies is provided whilst simultaneously also ensuring a low build-in space, i.e. an adequately low thickness. It is further advantageous that by the partition wall a sound reduction Rw of at least 55 dB can be achieved with a total partition wall thickness of 260 mm (10.24 inches) or less. 
     The airborne sound insulation designates the sound pressure reduction when sound is transmitted between two rooms through a building part, e.g. a wall, a door or a deck, and is described by the reduction index, R, with the unit decibel, dB. High values of R mean better airborne sound reduction. 
     Application rules, Measurements and Requirements for test facilities and equipment regarding sound insulation of building elements are specified according to building standards, such as the EN ISO 10140 series with the general title ‘Acoustics Laboratory measurement of sound insulation of building elements’. To evaluate the airborne sound insulation of a test specimen, the weighted sound reduction index, Rw, is used. The value is determined according to e.g. the European standard EN ISO 717, part 1. 
     The weighted airborne sound insulation measured in a laboratory is designated Rw, whereas the weighted airborne sound insulation measured in a building is designated R′w. For building parts that are only measured in a laboratory 4-6 dB is subtracted from the result in order to compensate for any flanking transmission that can be expected when built on site. 
     Performance requirements for party walls in many countries are typically specified in the Building Regulations prescribing a minimum airborne sound insulation, R′w. 
     Furthermore, the party wall has a fire reduction class of REI 60; meaning that it can uphold its load bearing capacity and withstand a fire in an adjacent room for 60 minutes. This is measured according to DS/EN 1363-1:2012 Fire resistance tests General requirements in conjunction with EN 1365-1: 2012 Fire resistance tests for loadbearing elements Part 1: Walls. 
     In some embodiments of a partition wall according to the disclosure, the first external wall cover may be secured by penetrating fasteners, such as nails or screws, penetrating through the first mounting elements and into the first spacer elements. Said first spacer elements might correspondingly be secured to the first intermediate profile and anchored in the central element of the column assembly. Similarly the second external wall cover may also be secured by penetrating fasteners, such as nails or screws, penetrating through the second mounting elements and into the second spacer elements. Accordingly the second spacer elements might be secured to either a second intermediate profile and being anchored in the central element of the column assembly, or a building board which beforehand has been secured to adjacent second intermediate profiles. The screws or nails or similar fasteners are typically made of steel or other metal alloys. 
     In a further advantageous embodiment the at least second spacer elements are moved in the plane of the second mineral wool fibre panels and mounted on the building board, e.g. an OSB board, at a location between two column assemblies and thus displaced from said columns. 
     The main fiber orientation of such second spacer element might be chosen to run substantially parallel to the plane of the wall and thereby providing a superior spring effect. The displaced spacer along with the said fiber orientation is further disrupting acoustical bridging. 
     According to a further preferred embodiment, at least the length of the first spacer elements and the thickness of the first mineral wool fibre panel is substantially the same. Hereby a compact sound insulating layer towards one of the building units is provided. 
     In yet another preferred embodiment, however, the length of the second spacer elements is larger than the thickness of the second mineral wool fibre panel whereby a space is provided between the inner mineral wool fibre panel and the second mineral wool fibre panel. Hereby, it is possible to provide a building board, such as an oriented strand board (OSB) or a flake board, in the space between the inner mineral wool fibre panel and the second mineral wool fibre panel and wherein said board is secured to two adjacently situated second intermediate profiles. This board can provide a further bracing and airtightness to the partition wall. 
     Preferably, the thicknesses of the first and second mineral wool fibre panels are substantially the same. This provides for a substantially symmetrical wall which is advantageous while easing erecting the wall and the sound insulation properties thereby can be expected to be similar in both sides. 
     The first and second external wall covers are preferably each made of at least one layer of gypsum board, said first and second external wall covers may have the same or a different number of layers. Hereby the symmetry can be established if an OSB board is provided and/or the wall covers in each of the building units can be provided according to the needs of each of the building units, such as the load of any wall hung items in the units. 
     Preferably, the central element of the column assembly is made of mineral wool fibres having a density of 300-600 kg/m 3  (18.73-37.46 lb/ft 3 ), preferably approx. 500 kg/m 3  (31.21 lb/ft 3 ). Hereby a rigid central element is provided for achieving excellent load-bearing properties of the partition wall. 
     Preferably, the first and second spacer elements are made of mineral wool fibres having a density of 70-150 kg/m 3  (4.37-9.36 lb/ft 3 ). Typically first and second spacer elements would comprise substantially the same density of approx. 100 kg/m 3  (6.24 lb/ft 3 ). 
     In an advantageous embodiment of the disclosure, the first spacer element has a first density which is different from a second density of the second element, such as a first density of approx. 100 kg/m 3  (6.24 lb/ft 3 ) and a second density of approx. 150 kg/m 3  (9.36 lb/ft 3 ). Hereby, the spring properties of the insulating spacer elements in the columns can be adjusted in order to achieve an optimised sound insulation; in particular in the lower density range. 
     Preferably, the inner mineral wool fibre panel has a density of 60-80 kg/m 3  (3.75-4.99 lb/ft 3 ), more preferably 70 kg/m 3  (4.37 lb/ft 3 ), and the first and second mineral wool fibre panels have a density in the range of 35-50 kg/m 3  (2.18-3.12 lb/ft 3 ), More preferably, the first and second mineral wool fibre panels have substantially the same density, and more preferably a density of approx. 45 kg/m 3  (2.81 lb/ft 3 ). By these density ranges a good sound insulation and fire properties are achieved and due to the relative low weight the partition wall according to these embodiments are easy to install. The main fibre orientation of the aforesaid mineral wool fibre panels is substantially parallel with the plane of the wall, i.e. a preferably laminar fibre orientation which has superior thermal properties. 
     In an embodiment, typically the at least one of the first and second spacer elements in the column assembly have a fibre orientation substantially parallel with the main fibre orientation of the first and second mineral wool panels. Hereby the spring properties can be adjusted according to actual requirements of the partition wall in order to further adjust the sound insulation properties thereof. 
     In yet another embodiment, the fibre orientation of the spacer elements in general might differ in that their main orientation is substantially perpendicular, e.g. lamellae-like, to that one of the first and second mineral wool panels. 
     As is apparent from the aforesaid the partition or party wall according to the present disclosure substantially comprises mineral wool fibre components with excellent sound, fire and load-bearing properties. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure is described in more detail in the following with reference to the accompanying drawings, in which: 
         FIG. 1  is a schematic cross-sectional view of a partition wall according to prior art; 
         FIG. 2  is a schematic cross-sectional view of a partition wall according to a first embodiment of the disclosure, 
         FIG. 3  is a schematic cross-sectional view of a partition wall according to a second embodiment of the disclosure; 
         FIG. 4  is a detailed view of a column assembly according to the second embodiment; 
         FIG. 5  is a schematic cross-sectional view of a partition wall according to a third embodiment of the disclosure; and 
         FIG. 6  is a detailed view of a column assembly according to this third embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     With reference to  FIG. 1 , it is known to construct a partition wall where two parallel rows of column profiles  1 ,  1 ′ are provided. The profiles  1 ,  1 ′ are metal sheet profiles mounted in two horizontal floor base profiles (not shown). Between the profiles  1 ,  1 ′, insulation slabs  2 ,  2 ′ are provided to form two separate “half walls”. On each side wall cover boards  3 ,  3 ′ are fastened to the sheet profiles  1 ,  1 ′. However, this incurs extra building time and costs as two base profiles must be installed and as the metal sheet profiles  1 ,  1 ′ extend across each of the “half walls”, and if not mounted accurately this may also result in spot where sound may travel through the partition wall. 
     Contrary to this prior art solution of  FIG. 1 , the present disclosure as exemplified in the two embodiments shown in  FIGS. 2 to 6 , provides a partition wall, more particular a party wall for a building structure comprising a plurality of building units separated by such partition wall to provide acoustic insulation and fire protection therebetween. 
     With reference to  FIG. 2  the said partition wall comprising a number of column assemblies  10  that are substantially vertically mounted in a generally horizontally oriented base profile (not shown). With reference also to the embodiment in  FIGS. 3 and 4 , each of the column assemblies  10  comprises a central element  11  made of mineral wool fibres and a first spacer element  12  and a second spacer element  13 . The first and second spacer elements  12 ,  13  are provided on each side of the central element  11 . The first and second spacer elements  12 ,  13  are made of mineral wool fibres and extend from the central element  11  and where first and second intermediate profiles  14 ,  15  are provided between the central element  11  and the first and second spacer elements  12 ,  13 , respectively. A column assembly  10  according to the before described embodiments would typically be prefabricated and columns being mounted in one piece. 
     Insulation sections  20 ,  21 ,  22  are fitted between the adjacent column assemblies  10 . The insulation sections comprise inner mineral wool fibre panels  20  provided in a close fit between the central elements  11  of two adjacent column assemblies  10 . First and second mineral wool fibre panels  21 ,  22  are provided in a close fit between the first and second spacer elements  12 ,  13 , respectively, of the adjacent column assemblies  10 . 
     An first external wall cover  31  abutting the first mineral wool fibre panels  21  and secured to the first mounting elements  33  of the adjacent column assemblies  10 , and a second external wall cover  32  abutting the second mineral wool fibre panels  22  and secured to the second mounting elements  34  of the adjacent column assemblies  10 . 
     In the column assemblies  10  in the partition wall according to the embodiments shown in  FIGS. 2, 3 and 4 , the density of the mineral wool in the central element  11  is higher than the density of the first and second spacer elements  12 ,  13 . The densities of the first and second mineral wool fibre panels  21 ,  22  are substantially the same or lower than the density of the inner mineral wool panels  20 . 
     By a partition wall according to the disclosure, very limited acoustic (or sound) bridges are present as the columns assemblies  10  are made of mineral wool fibres. Moreover, due to the relative high densities, the column assemblies  10  are stiff enough to provide stability and load-bearing properties to the wall construction. 
     The first external wall cover  31  is secured by penetrating fasteners  16 , such as nails or screws, penetrating through each the first mounting elements  33  and into the first spacer elements  12 . Said first spacer elements  12  correspondingly are secured to the first intermediate profile  14  and anchored in the central element  11  of the column assembly  10 . Similarly the second external wall cover  32  is secured by penetrating fasteners  16 , such as nails or screws, penetrating through the second mounting elements  34  and the second spacer elements  13 . Accordingly the second spacer elements  13  will be secured to either a second intermediate profile  15  and being anchored in the central element  11  of the column assembly  10 , or a building board  23  which beforehand has been secured to adjacent second intermediate profiles  15 . The screws or nails or similar fasteners are typically made of steel or other metal alloys. 
     In the shown embodiments in  FIGS. 2 and 3 , the length L 1  of the first spacer elements  12  and the thickness of the first mineral wool fibre panel is substantially the same. 
     The length L 2  of the second spacer elements  13  is larger than the thickness of the second mineral wool fibre panel  22  so that a space is provided between the inner mineral wool fibre panels  20  and the second mineral wool fibre panels  22  between two adjacent column assemblies  10 . In this space, a building board  23 , such as an oriented strand board (OSB) or a flake board, is provided and the board  23  is secured to two adjacently situated second intermediate profiles  15 . 
     In the shown embodiment the thicknesses of the first and second mineral wool fibre panels  21 ,  22  are substantially the same. 
     In the embodiment shown in  FIG. 2  the first and second external wall covers  31 ,  32  are each made of one layer of gypsum board. In the embodiment shown in  FIG. 3 , the first external wall cover  31  is made up by two gypsum boards. In general, it is realised by the present disclosure that first and second external wall covers  31 ,  32  may have the same or a different number of layers and may differ in material. 
     In the embodiments shown in  FIGS. 2 to 4 , each of the column assemblies  10  comprise a central element  11  made of mineral wool fibres and also a first spacer element  12  and a second spacer element  13 . 
     However, as shown in the embodiment of  FIGS. 5 and 6  it is found advantageous to displace the second spacer elements  13  so that the column assembly  10  comprises a central element  11  with a first and second intermediate profile  14 ,  15  on each side and a first spacer element  12  pointing towards the first side of the wall. Building boards  23  are provided in the space between the inner mineral wool panels  20  and the second mineral wool panels  22 . The second spacer elements  13  are provided in a displaced configuration in a position different from the columns  10  as shown in  FIG. 5 . In the embodiment shown in  FIG. 5  the second spacer elements  13  are secured to the building board  23  by a fastener, but could in an alternative embodiment be secured to the inner mineral wool panels, e.g. if no building board is provided. 
     In the embodiments of the figures, it is preferably that the central element  11  of the column assembly  10  is made of highly compacted mineral wool fibres having a density of 300-600 kg/m 3  (18.73-37.46 lb/ft 3 ), preferably approx. 500 kg/m 3  (31.21 lb/ft 3 ), and the first and second spacer elements  12 ,  13  are made of mineral wool fibres having a density of 70-150 kg/m 3  (4.37-9.36 lb/ft 3 ). 
     In an embodiment (not shown) the first spacer element  12  has a first density, such as a first density of approx. 100 kg/m 3  (6.24 lb/ft 3 ), which is different from the density of the second element  13  being approx. 150 kg/m 3  (9.36 lb/ft 3 ). Moreover, in order to provide a spring-mass dampening of the sound impacting the external wall covers  31 ,  32 , at least one of the first and second spacer elements  12 ,  13  in the column assemblies  10  have a fibre orientation of the spacer elements different in that their main orientation, which is substantially perpendicular, e.g. lamellae-like, to that one of the first and second mineral wool panels  21 ,  22 , such that e.g. the second spacer elements  13  are less compressible in the length direction. 
     In the currently preferred embodiments, the inner mineral wool fibre panels  20  have a density of 60-80 kg/m 3  (3.75-4.99 lb/ft 3 ), more preferably 70 kg/m 3  (4.37 lb/ft 3 ), and the first and second mineral wool fibre panels  21 ,  22  have a density in the range of 35-50 kg/m 3  (2.18-3.12 lb/ft 3 ) and more preferably the first and second mineral wool fibre panels  21 ,  22  have substantially the same density, and more preferably a density of approx. 45 kg/m 3  (2.81 lb/ft 3 ). 
     To test the sound reduction of a party wall according to two embodiments of the disclosure, test measurements were performed. 
     For the test, the partition walls in both embodiments comprise columns of 100 mm (3.94 inches) central elements mounted in U-profiles at the top and bottom. 
     One side of the central elements, the columns also consists of 50 mm (1.97 inches) first spacer elements that are screwed onto the central element with an intermediate profile in between. Onto these spacers wall cover of two layers of the Fermacell®-type, 15 mm (0.59 inches), were fastened by screws. 
     12 mm (0.47 inches) OSB plates are screwed on the second side of the columns via the second intermediate profiles. The OSB plates are butted together and openings between the plates are closed using tape. On the OSB plates approximately at the midway point between the columns a set of second spacer elements of 50 mm (1.97 inches) are screwed to the OSB plates. One layer of wall cover of the type Fermacell®, 15 mm (0.59 inches), is screwed onto these second spacer elements. 
     The cavities between the central portions of the columns are filled with 100 mm (3.94 inches) inner mineral wool fibre panels of 70 kg/m 3  (4.37 lb/ft 3 ), whereas the cavities between the first spacer elements and the cavities between the second spacer elements are filled with 50 mm first and second mineral wool fibre panels of 45 kg/m 3  (2.81 lb/ft 3 ). 
     The total thickness of the partition wall is approx. 260 mm (1.97 inches) and with a weight of approx. 71 kg/m 2  (4.43 lb/ft 3 ). 
     The wall was mounted between two reverberation rooms in a 1.15 m (45.28 inches) deep concrete frame with a width of 3.70 m (145.67 inches) and a height of 2.69 m (105.91 inches). 
     Laboratory measurement of sound reduction index was carried out according to the EN ISO 10140:2010 part 1, 2, 4 and 5. The test results were evaluated according to EN ISO 717-1:2013. 
     In a first measurement regarding sound insulation of building elements, i.e. a party wall according to the embodiments of  FIG. 3 , there was found a minimum airborne sound insulation Rw of 55 dB. 
     In a second measurement regarding sound insulation of building elements, i.e. a party wall according to the embodiment of  FIG. 5 , there was measured a minimum airborne sound insulation Rw of 60 dB. 
     Above the disclosure is described with reference to some preferred embodiment. However, by the disclosure it is realised that variants and equivalences to one or more of the features also fall within the scope of the disclosure as defined in the accompanying claims.