EP3739140B1

EP3739140B1 - A fire retaining wall structure assembly for partitioning adjacent spaces

Info

Publication number: EP3739140B1
Application number: EP19174853.2A
Authority: EP
Inventors: Jarkko Kuisma
Original assignee: Muotolevy Oy
Current assignee: Muotolevy Oy
Priority date: 2019-05-16
Filing date: 2019-05-16
Publication date: 2022-04-13
Anticipated expiration: 2039-05-16
Also published as: EP3739140A1

Description

FIELD OF THE DISCLOSURE

The disclosure relates to a fire retaining wall structure assembly for partitioning adjacent spaces, and more particularly to such wall structure assemblies for partitioning adjacent spaces between which heat-insulation is not needed or suitable.

BACKGROUND OF THE DISCLOSURE

Typically, wall structure assemblies for partitioning adjacent spaces are constructed by providing a wall structure having a frame which is covered with board elements to form the wall surfaces. Fire retaining properties for such wall structure assembiles are achieved by using fire-restraining board elements and/or providing an intermediate space (i.e. the space between the board elements) with a fire retaining thermal insulation, such as mineral wool or glass wool.
In certain applications such thermal insulation may not be needed, or it may not even be suitable. Particularly, condensation of humidity in the thermal insulation increases the risk of e.g. microbial growth within the wall structure assembly, thus leading to air-quality related problems. Such humidity related risks are particularly prominent in wall structure assemblies between non-heated spaces (such as parking facilities in the proximity of other buildings, or neighbouring balconies, etc), or otherwise humid environments (such as bathing facilities or other facilities in which large amounts of moisture is present).
Moreover, moisture related microbial growth may cause problems in fire retaining wall structure assemblies in non-heated or otherwise humid environments even when no thermal insulation is provided within the wall structure assembly. This is because such fire retaining wall structure assemblies are most often constructed in a sealed manner in order to achieve the fire retaining properties. This, in turn, means that moisture once trapped within the structure can not be ventilated and may condensate within the structure during temperature changes.
However, a fire retaining structure may often be needed between adjacent places in non-heated or otherwise humid environments in order to comply with fire and safety regulations.
Moreover, it has been noted, that vertically extending studs of a wall frame often deform during a fire, thereby breaking any elements attached to it, and further causing catastrophic failure of the fire retaining capability. This phenomenon is particularly prominent with metal-stud frames, as the studs expand and warp due to thermal expansion but is also applicable other types of frames which deform when consumed by the fire (e.g. wooden frames. US 2009/282759 A1 discloses a fire retaining wall structure with the features of the preamble of claim 1.

BRIEF DESCRIPTION OF THE DISCLOSURE

An object of the present disclosure is to provide a fire retaining wall structure assembly for partitioning adjacent spaces. It is a further object of the present disclosure, to provide such wall structure assembly, that is suitable for partitioning adjacent spaces in non-heated or otherwise humid environments while minimizing the risk of problems related to microbial growth within the wall structure assembly.
The object of the disclosure is achieved by a fire retaining wall structure assembly, which is characterized by what is stated in the independent claims. The preferred embodiments of the disclosure are disclosed in the dependent claims.
The disclosure is based on the idea of providing the wall structure assembly with two separate frames which are unattached to each other, and providing a fire retaining intermediate layer between the frames, which is unattached at least from vertically extending studs of the frames. Moreover, the frame is provided with an opening allowing ventilation of the inside of the wall structure assembly.
An advantage of arrangement of the disclosure is that a wall structure assembly having excellent fire retaining properties with minimal risk of microbial growth even in non-heated or otherwise humid environments is achieved. Particularly, the use of separate, unattached frames ensures that deformation of either frame caused by a fire on one side of the wall will not induce structural failure of the fire retaining intermediate layer, the other frame or the wall surface on the opposing side, thereby increasing the longevity of the wall structure assembly in a fire. Moreover, the ventilation of the inner space ensures and the fact that conventional thermal insulation, such as mineral or glass wool, is not used ensures that moisture does not condensate within the wall structure assembly, thereby contributing to minimizing the risk of microbial growth within the wall structure assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following the disclosure will be described in greater detail by means of preferred embodiments with reference to the accompanying drawings, in which

Fig. 1 illustrates a fire retaining wall structure assembly according to an embodiment of the present disclosure, as seen as an isometric exploded view, and
Fig. 2 illustrates the fire retaining wall structure assembly of Fig. 1 as seen as a cross-sectional view along a first lateral direction of the wall assembly structure.

DETAILED DESCRIPTION OF THE DISCLOSURE

According to a first aspect of the present disclosure, a fire retaining wall structure assembly 1 for partitioning adjacent spaces 2a, 2b is provided. For example, the adjacent spaces may be non-heated spaces (such as parking facilities or neighbouring balconies, etc), or otherwise humid environments (such as bathing facilities or other facilities in which large amounts of moisture is present).
The fire retaining wall structure 1 comprises a first frame 3, which in turn, comprises a set of vertically extending first studs 3a spaced apart from each other in a first lateral direction L1, and one or more first cladding elements 4a attached at least to one or more of the first vertically extending studs 3a, thereby forming a first outer surface 4.
The fire retaining wall structure 1 further comprises a second frame 5, which in turn, comprises a set of vertically extending second studs 5a spaced apart from each other in a first lateral direction L1, and one or more second cladding elements 6a attached at least to one or more of the second vertically extending studs 5a, thereby forming a second outer surface 6.
Particularly, the first frame 3 and the second frame 5 are separate from each other and spaced apart from each other in a second lateral direction L2. That is, the frames 3, 5 are unattached to each other by the wall structure assembly and an intermediate space is formed therebetween.
The wall structure assembly 1 further comprises a fire-retaining intermediate layer 7 formed by one or more intermediate board elements 7a supported between the first frame 3 and the second frame 5, said intermediate layer 7 being unattached at least to the first vertical studs 3a and the second vertical studs 5a.
Furthermore, the first outer surface 4 may be equipped with at least an opening 3b for allowing ventilation of the space between the first outer surface 4 and the intermediate layer 7, or the second outer surface 6 may be equipped with at least an opening 5b for allowing ventilation of the space between the second outer surface 6 and the intermediate layer 7. Such an opening may be provided, for example, at a bottom and/or top end of the outer surface 4, 6. Most suitably such openings 3b, 5b are provided as slots extending in the first lateral direction L1. Preferably, but not necessarily, such openings 3b, 5b could be provided as slots extending the whole width of the respective outer surface 4, 6 in the first lateral direction L1, for example by arranging the corresponding cladding elements 4a, 6a at a distance from the respective floor and/or ceiling surface. That is, the openings 3a, 3b, could be provided by leaving a gap between the outer surface 4, 6 and either or both of the floor surface and the ceiling surface. Alternatively, the openings 3a,3b may be provided as single or multiple separate openings.
Most suitably, openings 3a, 3b are provided at both the first outer surface 4 and the second outer 6 surface, respectively. Furthermore, the openings are 3a, 3b are advantageously provided both at the top and bottom edges of the outer surfaces 4, 6. This ensures sufficient airflow to achieve efficient ventilation on both sides of the intermediate layer 7, thereby ensuring that moisture-related risks are minimized.
In the context of this disclosure, the first lateral direction L1 is used to depict a horizontal direction running parallel with the outer surfaces 4, 6 of the wall structure assembly. Correspondingly, the second lateral direction L2 is used to depict a horizontal direction normal to the outer wall surfaces 4, 6.
Preferably, but not necessarily, the frames 3, 5 may be of a metal stud 3a, 5a, structure. Alternatively, the frames may be constructed of otherwise, such as from lumber.
In a fire situation, where a fire prevails on a single side (hot side) of the wall structure assembly 1, the fire retaining wall structure assembly 1 according to the present disclosure prevents or slow the spreading of the fire to the opposing side (cool side) of the wall structure assembly in a following manner.
Firstly, the fire is slowed down by the board elements 4a, 6a of the outer wall surface 4, 6 on the hot side, momentarily protecting the remaining wall structure assembly 1.
When the board elements 4a, 6a become consumed by the fire, the fire begins to act upon the frame 3, 5 on the hot side. The vertically extending studs 3a, 5a are eventually deformed due to the fire. The deformation may be caused, for example, simply by the vertically extending studs 3a, 5b being consumed by the fire, or, in the case of a metal frame, by the heat expansion of the studs 3a, 5a. Although heat-expansion derived deformation may be minimized by allowing sufficient space for the heat expansion, as discussed at a later stage, even metal studs 3a, 5a will eventually deform under the weight of the cladding elements 4a, 6a when the temperature of the fire causes the studs 3a, 5a to loose rigidity, i.e. become malleable Because the intermediate layer 7, and the frame 5, 3 on the cool side are unattached to the studs 3a, 5a on the hot side, the deformation of the hot side vertically extending studs 3a, 5a does not break the intermediate layer 7 or the cool side frame 5, 3, which increases the longevity of the remaining wall structure assembly in a fire. That is, the wall structure assembly according to the present disclosure ensures, that the fire retaining intermediate layer 7 layer stays intact longer, thus providing better protection from fire.
In an embodiment according to the first aspect of the present disclosure, the first cladding element 4a, second cladding element 6a, or both, are board elements. For example, the cladding elements 4a, 6a may be provided as clapboard, or more preferably, cladding board, such as cement based board, gypsum-based board, ceramic board, metal sheeting or board made of natural stone. Moreover, the cladding elements 4a, 6a are most suitably weather resistant cladding elements. It should be noted that the cladding elements 4a, 4b on the opposite wall surfaces 4, 6 may be chosen independently.
In another embodiment according to the first aspect of the present disclosure, that the intermediate board element 7a may be provided as a fire retaining board element 7a.
Particularly, in the context of this disclosure, the fire retaining intermediate board element 7a is used to depict a self-supporting board (i.e. a board that is rigid enough so that it maintains its shape and form without external support) and maintains its rigidity at elevated temperatures associated to a fire. Most suitably, the intermediate board element 7a is either non-combustible (does not contribute to fire) or fire-retardant (slows down the spreading of a fire). Moreover, in order to prevent moisture-related issues, such as microbial growth, the intermediate board element 7a is advantageously either moisture-resistant, mould-resistant, or both.
Examples of particularly suitable intermediate board elements 7a include gypsum-based boards, cement-based boards and magnesium-oxide-based boards which are sufficiently moisture-resistant and / or mould-resistant. Also, moisture-resistant and/or mould-resistant grades of plywood and oriented strand board (OSB) have been found to provide sufficient fire-retention properties by slowing down the advancement of the fire through the wall structure assembly.
By contrast, conventional thermal insulation elements, such as fibre-based insulation mats, are generally not considered suitable as intermediate board elements 7a, as they are both slack (i.e. non-rigid) and porous (non-moisture-resistant.
In another embodiment according to the first aspect of the present disclosure, the intermediate layer 7 may comprise two or more intermediate board elements (7a) superimposed in the second lateral direction L2. That is, the intermediate layer 7 may have two or more plies of intermediate board members 7a.
In another embodiment according to the first aspect of the present disclosure, the opening(s) 3b of the first frame 3, the opening(s) 5b of the second frame 5a, or both, are equipped with an intumescent element for sealing said opening(s) 3b, 5b. This ensures that proper ventilation may be achieved into the inside of the wall structure assembly, while preventing fire from spreading thereto via the ventilation openings 3a, 5a.
Moreover, it has been found out that, during a fire, ventilation provided through the openings on the cool side of the wall structure assembly initially slows down the spreading of the fire through the wall structure assembly due to a convention induced air flow that cools the wall assembly structure. When the temperature rises and the fire begins to break through also to the cool side, the intumescent elements seal the openings, thus preventing the air flow and additional oxygen feed to the fire.
In another embodiment according to the first aspect of the present disclosure, a sealing strip is provided between either or both of the first cladding elements 4a and the first frame 3, and respectively, the second cladding elements 6a and the second frame 5, for sealing the seam between adjacent cladding elements 4a, 6a on an inner side thereof.
This prevents, or at least restraints, the fire from entering the inside of the wall structure assembly through the seams between adjacent cladding elements 4a, 6a. For example, fire resistant glazing strip may be used as the sealing strip. Preferably, but not necessarily, a self-adhesive glazing strip is used as the sealing strip
In another embodiment according to the first aspect of the present disclosure, the first frame 3, the second frame 5, or both, comprise a floor rail 3c, 5c attachable to a floor structure and a ceiling rail 3d, 5d attachable to a ceiling structure. Particularly, the floor rail 3c, 5c and the ceiling rail 3d, 5d are arranged for receiving a top end and a bottom end of the vertically extending studs 3a, 5a, respectively.
Suitably, the floor rail 3c, 5d and ceiling rail 3d, 5d are of a similar construction as the remaining frame. As discussed above, a metal profile frame is used, for example. In such a case, top and bottom ends of the vertically extending studs 3a, 5a are received in a base of the U-profiled ceiling rail 3d, 5d and floor rail 3c, 5c, respectively. Alternatively, a wooden frame construction, including the rails, may be used.
Preferably, but not necessarily, the intermediate layer 7 is attached to at least one of the ceiling rail of the first frame 3, the floor rail of the first frame 3, the ceiling rail of the second frame 5, or the floor frame of the second frame 5. In practise, the intermediate layer is typically attached to the rails 3c, 5c; 3d, 5d of only either frame 3, 5. If a presumed side of a fire, or a primary direction of fire protection is known, the intermediate layer, is attached to the rails 3c, 5c; 3d; 5d of the frame 3, 5 which is presumed to be on the cool side or the side of primary protection, thereby ensuring that the intermediate layer 7 stays in position even when the frame 3, 5 on the hot side is consumed by the fire.
This helps hold the intermediate layer in place during installation of the wall structure assembly. It has been found out that the floor rails 3c, 5c and ceiling rails 3d, 5d do not excessively deform during a fire, thereby allowing the intermediate layer 7 to be attached to the rails without causing it to break due to frame 3, 5 deformation during a fire.
Suitably, if an intermediate layer 7 having multiple plies, as discussed above, is used, both plies are preferably attached to the same frame 3, 5.
Moreover, in order to prevent the deformation of the vertically extending studs 3a, 5a form breaking the intermediate layer 7, the intermediate layer should be attached to the floor rails 3c, 5c or ceiling rails 3d, 5d at positions that do not intersect with the vertically extending studs 3a, 5a. For example, if the board elements 7a are attached to the rails 3c, 5c; 3d, 5d by screwing, the positions of the screws should be select such that they do not extend into the vertically extending studs 3a, 5a.
Preferably, but not necessarily, the top end of the vertical studs 3a, 5a is spaced apart from a base of the corresponding ceiling rail 3d, 5d. This minimizes the deformation of the vertically extending stud due to thermal expansion by allowing sufficient space for the expansion of the vertically extending stud 3a, 5a into the ceiling rail 3d, 5d.
Again, preferably, but not necessarily, the wall structure assembly 1 further comprises a spacing element 3e, 5e arranged between a bottom end of a vertical stud 3a, 5a and the corresponding floor rail 3c, 5c. Most suitably, such spacing elements 3e, 5e should be sufficiently weak or fragile so as to break under thermal expansion of the vertically extending studs 3a, 5a towards the base of the floor rail 3c, 5c. For example, strips made from gypsum-based board may be used. Preferably, but not necessarily such spacing element 3e, 5 are made from moisture-resistant and/or mould -resistant gypsum-based board. Again, the spacing elements 3e, 5e minimize the deformation of the vertically extending stud due to thermal expansion by allowing sufficient space for the expansion of the vertically extending stud 3a, 5a into the floor rail 3c, 5c.
In another embodiment according to the first aspect of the present disclosure either or both of the first frame 3 and second frame 5 comprise one or more horizontally extending beams 3f, 5f arranged between adjacent vertically extending studs 3a, 5a. Moreover, the horizontally extending beams 3f, 5f, in turn, comprises one or more openings for allowing ventilation therethrough between a space above, and respectively, below the corresponding horizontally extending beam 3f, 5f. The horizontally extending beams 3f,5f increase the structural rigidity of the corresponding frame 3,5, while the opening therein allow ventilation, encompassing the advantages related to the cooling effect during a fire and reducing moisture-related risks, as discussed above.
It should be noted, that the first aspect of the present disclosure also encompasses combinations of the embodiments, and variants thereof, as discussed above.

Claims

A fire retaining wall structure assembly (1) for partitioning adjacent spaces (2a, 2b), comprising:
a first frame (3) comprising a set of vertically extending first studs (3a) spaced apart from each other in a first lateral direction (L1), and one or more first cladding elements (4a) attached at least to one or more of the first vertically extending studs (3a), thereby forming a first outer surface (4),

a second frame (5) comprising a set of vertically extending second studs (5a) spaced apart from each other in a first lateral direction (L1), and one or more second cladding elements (6a) attached at least to one or more of the second vertically extending studs (5a), thereby forming a second outer surface (6),

wherein the first frame (3) and the second frame (5) are separate from each other and spaced apart from each other in a second lateral direction (L2), and wherein the wall structure assembly (1) further comprises a fire-retaining intermediate layer (7) formed by one or more intermediate board elements (7a) supported between the first frame (3) and the second frame (5), characterised in that said intermediate layer (7) is unattached at least to the first vertical studs (3a) and the second vertical studs (5a), and

in that either the first outer surface (4) is equipped with at least an opening (3b) for allowing ventilation of the space between the first outer surface (4) and the intermediate layer (7), the second outer surface (6) is equipped with at least an opening (5b) for allowing ventilation of the space between the second outer surface (6) and the intermediate layer (7), or both.
The fire retaining wall structure assembly according to Claim 1, characterized in that the first cladding element (4a), second cladding element (6a), or both, are board elements.
The fire retaining wall structure assembly according to Claim 1 or 2, characterized in that the intermediate board element (7a) is a fire-retaining board element.
The fire retaining wall structure assembly (1) according to any of the preceding Claims 1-3, characterized in that the intermediate layer (7) comprises two or more intermediate board elements (7a) superimposed in the second lateral direction (L2).
The fire retaining wall structure assembly (1) according to any of the preceding Claims 1-4, characterized in that an opening (3b) of the first frame (3), opening (5b) of the second frame (5a), or both, are equipped with an intumescent element for sealing said opening (3b, 5b).
The fire retaining wall structure assembly (1) according to any of the preceding Claims 1-5, characterized in that a sealing strip is provided between either or both of the first cladding elements (4a) and the first frame (3), and respectively, the second cladding elements (6a) and the second frame (5), for sealing the seam between adjacent cladding elements (4a, 6a) on an inner side thereof.
The fire retaining wall structure assembly (1) according to any of the preceding Claims 1-5, characterized in that the first frame (3), the second frame (5), or both, comprise a floor rail (3c, 5c) attachable to a floor structure and a ceiling rail (3d, 5d) attachable to a ceiling structure,
wherein the floor rail (3c, 5c) and ceiling rail (3d, 5d) are arranged for receiving a top end and a bottom end of the vertically extending studs (3a, 5a), respectively.
The fire retaining wall structure assembly (1) according to Claim 7, characterized in
that the intermediate layer (7) is attached to at least one of the ceiling rail (3d of the first frame (3), the floor rail (3c) of the first frame (3), the ceiling rail (5d) of the second frame (5) or the floor frame (5c) of the second frame (5).
The fire retaining wall structure assembly (1) according to Claims 7 and 8, characterized in that the top end of the vertical studs (3a, 5a) is spaced apart from a base of the corresponding ceiling rail (3d, 5d).
The fire retaining wall structure assembly (1) according to any of the preceding Claims 7-9, characterized in that the wall structure assembly (1) further comprises a spacing element (3e, 5e) arranged between a bottom end of a vertical stud (3a, 5a) and the corresponding floor rail (3c, 5c).
The fire retaining wall structure assembly (1) according to any of the preceding Claims 1-10, characterized in that either or both of the first frame (3) and second frame (5) comprise one or more horizontally extending beams (3f, 5f) arranged between adjacent vertically extending studs (3a, 5a), wherein the horizontally extending beam (3f, 5f), in turn, comprises one or more openings for allowing ventilation therethrough between a space above, and respectively, below the corresponding horizontally extending beam (3f, 5f).