The present invention relates to a building fagade with a sheathing in form of fagade elements which is provided with a fire barrier.

Prior art

Fire barriers for the cavity between the outer surface of the building fagade and the fagade elements is known in the art from GB 2589194 comprises a fire barrier in the form of a barrier element comprising a heat-expanding fire barrier with an intumescent material mounted to the building fagade, so that ventilation of the cavity when the fire barrier is not activated by a fire is ensured.

The provision of fire barriers in such cavities at the position of floor separation of a building is a requirement in many jurisdictions.

However, the surface of the building fagade is often constituted by thermally insulating material with a windproof sheet material covering the insulating material, and the mounting of the fire barrier to the building surface often requires modification to such insulating material. It is an object of the present invention to provide a sheathing of an outer surface of a building fagade where the fire barrier is mounted more easily.

Brief description of the present invention

The inventor has realised that the object can be met by fixing the fire barrier to the mounting rails which supports the fagade elements forming part of the building envelope instead of fixing it to the building fagade.

Thus, the present invention relates to a sheathing of an outer surface of a building facade, the sheathing comprising a plurality of mounting rails, each supported by the building fagade, a plurality of fagade elements being fixed to the mounting rails to form a substantially closed part of a building envelope, the sheathing further comprising at least one heat-expanding fire barrier extending horizontally and comprising an intumescent material, so as to ensure that the space between the outer surface of the building fagade and the fagade elements can be filled by the fire barrier in case of fire. It is advantageous that the fire barrier is supported on one or more of the mounting rails by mechanical means. In one or more embodiment, the mechanical means are designed to be horizontally displaceable between the building fagade and the fagade elements by the force exerted by the intumescent material in case of fire.

The plurality of mounting rails may comprises a plurality of vertical mounting rails fixed to the building fagade with a mutual distance in the horizontal direction between neighbouring vertical mounting rails. Furthermore, the plurality of mounting rails may comprise a plurality of horizontal mounting rails, each of which is fixed to a plurality of the vertical mounting rails so that the vertical mounting rails extends between the horizontal mounting rails and the surface of the building fagade.

In one or more embodiments, the fire barrier can be supported on one or more horizontal mounting rails. In one or more embodiments, the fire barrier can be supported on an upper facing side of the one or more horizontal mounting rails. In one or more embodiments, the fire barrier can be supported on a lower facing side of the one or more horizontal mounting rails. In one or more embodiments, the fire barrier can be supported on a vertical facing side of the one or more horizontal mounting rails.

In one or more embodiments, the fire barrier can be supported on one or more vertical mounting rail. In one or more embodiments, the fire barrier can be supported on an upper facing side of the one or more vertical mounting rails. In one or more embodiments, the fire barrier can be supported on a lower facing side of the one or more vertical mounting rails. In one or more embodiments, the fire barrier can be supported on a vertical facing side of the one or more vertical mounting rails.

In one or more embodiments, the mechanical means can be fire barrier rails. The fire barrier rails can be designed to be horizontally displaceable between the building facade and the fagade elements by the force exerted by the intumescent material in case of fire.

In one or more embodiments, the intumescent layer can be provided on a surface of the fire barrier rail. In one or more embodiments, the fire barrier rail, can be arranged to extend horizontally in the ventilated cavity between an inner surface of the fagade element and an intumescent layer provided on a surface of the fire barrier rail facing the outer surface of the building fagade.

In one or more embodiments, the fire barrier comprises a fire barrier rail, which is arranged to extend horizontally in the ventilated cavity between an inner surface of the fagade element and an intumescent layer provided on a surface of the fire barrier rail facing the outer surface of the building fagade, which is arranged so that in case of fire, the intumescent layer will expand and come into abutment with the outer surface of the building fagade, whereby the fire barrier effectively blocks the ventilated cavity.

In one or more embodiments, the mechanical means can be a device/holder for holding the fire barrier. The device/holder can be designed to be horizontally displaceable between the building fagade and the fagade elements by the force exerted by the intumescent material in case of fire.

In one or more embodiments, the mechanical means can be mounting hooks, screws, fittings, staples, bolt and nut or similar. The mounting hooks, screws, fittings, staples, bolt and nut or similar can be designed to be horizontally displaceable between the building fagade and the fagade elements by the force exerted by the intumescent material in case of fire.

In one or more embodiments, the mechanical means are clips. In one embodiment, it is advantageous that the fire barrier is supported on one or more of the mounting rails by means of clips which are designed to be horizontally displaceable between the building fagade and the fagade elements by the force exerted by the intumescent material in case of fire.

In one or more embodiments, the fire barrier rails can be mounted to the one or more of the mounting rails by mounting hooks, screws, fittings, staples, bolt and nut or similar. In one or more embodiments, the device/holder for holding the fire barrier can be mounted to the one or more of the mounting rails by mounting hooks, screws, fittings, staples, bolt and nut or similar.

The fire barrier is situated in the ventilated cavity between the outer surface of the building fagade and an inner surface of the fagade elements, and the fire barrier will typically have a distance to the building fagade and the inner surface of the fagade elements for a simple installation and to compensate for variations in position of the components of the sheathing and the building fagade. To achieve that, it has been found by the inventor that the fire barrier should preferably be is supported on one or more of the mounting rails so that the fire barrier is horizontally displaceable between the building fagade and the fagade elements by the force exerted by the intumescent material in case of fire so as to ensure that the space between the outer surface of the building fagade and the fagade elements can be filled by the fire barrier.

In a preferred embodiment, the fire barrier comprises a layer of the intumescent material and a layer of a flexible, non-combustible material, such as mineral wool or glass wool, which preferably has a thickness of 10 to 70 millimetres, such as 15 to 65 millimetres.

The fire barrier is preferably horizontally displaceable by at least 5 millimetres, such as at least by 10 millimetres by the force exerted by the intumescent material in case of fire so as to compensate for the varying distance between the fire barrier, the outer surface of the building fagade and the fagade elements, respectively.

The horizontal distance between the surface of the building fagade and the fagade elements at a position of a fire barrier is preferably at least 15 millimetres less that the horizontal extent of the fire barrier, such as at least 25 millimetres, which constitutes the ventilated cavity.

In a preferred embodiment, distance means are provided to ensure a minimum distance between the fire barrier and the outer surface of the building fagade of at least 10 millimetres, preferably at least 20 millimetres when the intumescent material is unexpanded, since it is advantageous to provide a ventilation space right next to the outer surface of the building fagade because a diffusion of humidity from the inside of the building and out through the building fagade can be foreseen.

Said distance means preferably comprises a part being in abutment with the outer surface of the building fagade.

The mechanical means may be designed to constitute said distance means.

The fire barrier rails may be designed to constitute said distance means The device/holder may be designed to constitute said distance means. The clips may be designed to constitute said distance means.

It appears to be advantageous if the intumescent material is arranged to expand towards the outer surface of the building fagade, so that the expanded intumescent material comes into contact with the outer surface of the building fagade in case of fire.

It is preferred that fire barrier extends substantially the full horizontal extent of the sheathing so as to provide a full fire barrier between floors of the building.

In a particularly preferred embodiment, the plurality of mounting rails comprises a plurality of vertical mounting rails fixed to the building fagade with a mutual distance in the horizontal direction between neighbouring vertical mounting rails.

Furthermore, the plurality of mounting rails may comprise a plurality of horizontal mounting rails, each of which is fixed to a plurality of the vertical mounting rails so that the vertical mounting rails extends between the horizontal mounting rails and the surface of the building fagade.

The vertical mounting rails at a position of the fire barrier is in a preferred embodiment formed to allow for the fire barrier to expand into abutment with the surface of the building fagade, e.g. by removing parts of the vertical mounting rails otherwise extending away from the outer surface of the building fagade. The outer surface of the building fagade is preferably constituted by thermally insulating material or a windproof sheet material, in particular thermally insulating material covered by a windproof sheet material, such as a plate material or fabric, which windproof sheet material constitutes the outer surface of the building fagade.

Brief description of the drawing

Different embodiments of the present invention are illustrated in the enclosed drawing of which:

Fig. 1 is a cross-section of a first embodiment of the sheathing of an outer surface of a building fagade,

Fig. 2 is a cross-section of the embodiment of Fig. 1 in which the intumescent material is in an expanded state due to exposure to heat,

Fig. 3 is a cross-section of a second embodiment of the sheathing of an outer surface of a building fagade,

Fig. 4 is a cross-section of a third embodiment of the sheathing of an outer surface of a building fagade,

Fig. 5 is a cross-section of a fourth embodiment of the sheathing of an outer surface of a building fagade, and

Fig. 6 is a cross-section of a fifth embodiment of the sheathing of an outer surface of a building fagade.

The present invention is not limited to the embodiments shown in the drawing and which are discussed below, as this is intended to illustrate possible manners of carrying the present invention out.

Detailed description of embodiments

The embodiment of the sheathing of an outer surface of a building fagade shown in Figs. 1 and 2 comprises a plurality of fagade elements 1 , which are fixed by means of screws 2 in a staggered manner to horizontal mounting rails 3. The horizontal mounting rails 3 are fastened to the building fagade 4 via a set of vertical mounting rails 5. The building fagade 4 comprising a load bearing inner wall (not shown) on which the vertical mounting rails 5 are supported, covered by a thermally insulating material (not shown), such as e.g. mineral wool, and a windproof sheet material 6, such as fibre cement plate material.

A vertical fire barrier 7 is mounted in the ventilated cavity 8 between the building facade 4 and the fagade elements 1 , the fire barrier 7 extending along the position of a floor separation of the building to prevent a possible fire from spreading in the vertical direction and to hinder a stack effect (also known as chimney effect) of the ventilated cavity 8 in case of a fire, which can may feed the fire with air. The fire barrier comprises a vertically extending intumescent layer 9 facing the outer surface 10 of the building fagade 4 and a 37 millimetres thick layer of a flexible, non-combustible material 11 , such as mineral wool or glass wool.

The fire barrier 7 is mounted to the vertical mounting rails 5 by means of clips 12 distributed along the horizontal extent of the fire barrier 7. The clips 12 have an upper hook 13 for engaging with an upward facing edge 14 of the horizontal mounting rails 3, a C-shaped body 15 to support the fire barrier 7 and a distance member 16 arranged to be in abutment with the outer surface 10 of the building fagade 4 and ensure a minimum air gap of 15 millimetre between the intumescent layer 9 and the outer surface 10 of the building fagade 4 when the intumescent layer 9 is not expanded, so as to provide ventilation to the structure.

The vertical mounting rails 5 are discontinued at the vertical position of the fire barrier 7, so as to ensure that the intumescent layer 9 will come unhindered into abutting contact with the outer surface 10 of the building fagade 4 in case of a fire. In an alternative embodiment, only the part of the vertical mounting rails 5 extending out from the outer surface 10 is removed, while the part which is flush with the outer surface 10 is continued across the position of the fire barrier 7.

The cross-sectional view of Fig. 1 shows the first embodiment of the sheathing of an outer surface of a building fagade when mounted, and Fig. 2 shows the embodiment in which the intumescent material 9 is in an expanded state due to exposure to heat, i.e. during a fire. When the intumescent layer 9 expands towards the outer surface 10 of the building fagade 4 and comes into abutting contact with that surface 10, the further expansion of the intumescent layer 9 will exert a force on the layer 11 of flexible, non-combustible material in the opposite direction towards the fagade elements 1 , which will cause the layer 11 of flexible, non-combustible material to be displaced towards the fagade elements 1 and come into abutting contact with an inner surface 17 of the fagade element 1 , whereby the fire barrier 7 effectively blocks the ventilated cavity 8. The design of the clips 12 allows for this horizontal displacement of the fire barrier 7 by 10 to 15 millimetres.

The second embodiment shown in Fig. 3 deviates from the first embodiments in that the fagade elements 1 are equipped with support elements 18 projecting from the inner surface 17 of the fagade element, where the support elements are arranged to cooperate with an upward facing edge 14 of the horizontal mounting rails 3.

The upper hook 13 of the clips 12 utilized to support the fire barrier 7 are in this embodiment formed to engage with a lower protrusion 18 of the horizontal mounting rail 3, and the support of the fire barrier 7 is made flexible to as to allow for a horizontal displacement of the fire barrier 7 in case of fire just as for the first embodiment, so as to ensure that the fire barrier 7 effectively blocks the ventilated cavity 8. The clips 12 is also provided with a biasing arm 19 arranged to bias the clips 12 towards the outer surface 10 of the building fagade 4 for the distance member 16 of the clip 12 to be in abutment with the outer surface 10.

The third embodiment shown in Fig. 4 deviates from the first embodiment of Figs. 1 and 2 in that the fagade elements 1 are formed differently and leaves a more shallow ventilated cavity 8 between the outer surface 10 of the building fagade 4 and the inner surface 17 of the fagade elements 1 , for which reason the thickness of the layer 11 of flexible, non-combustible material of the fire barrier 7 is reduced to 18 millimetres as compared to the first embodiment shown in Figs. 1 and 2.

The fourth embodiment shown in Fig. 5 deviates from the one shown in Fig. 4 in the method of mounting the fagade elements 1 to the horizontal mounting rails 3, which in this embodiment is done by means of facade mounting fastener 20, which are suspended from the horizontal mounting rails 3 and supports the lower edge of the fagade elements 1. Also, the upper hook 13 of the clips 12 is formed differently to fit with the upward facing part 21 of horizontal mounting rail 3.

In the fifth embodiment shown in Fig. 6, the fire barrier 7 comprises a horizontal fire barrier rail 22 mounted to the horizontal mounting rail 3 by means of screws 2. The fire barrier rail 22 blocks the ventilated cavity 8 between the inner surface 17 of the fagade element 1 and the intumescent layer 9 provided on a surface of the fire barrier rail 22 facing the outer surface 10 of the building fagade 4, leaving an air gap of IQ- 20 millimetre between the latter two. In case of fire, the intumescent layer 9 expands and come into abutment with the outer surface 10 of the building fagade 4, thereby closing the air gap, whereby the fire barrier 7 effectively blocks the ventilated cavity 8.

Elements of the various embodiments may be exchanged between the embodiments and other embodiments of the present invention may be envisioned.

The fagade elements 1 are in all embodiments shown in a configuration, wherein the facade elements 1 are mounted so that they form an angle relative to the outer surface 10 of the building facade 4, and wherein the facade elements 1 partially overlap each other. This is an advantageous configuration of the present invention, as the mounting of the fire barrier 7 generally allow for the variation in distance between the outer surface 10 of the building fagade 4 and the inner surface 17 of the fagade elements 1. However, the present invention also encompasses a configuration, where the facade elements 1 are mounted in parallel with the outer surface 10 of the building facade 4, so that the outer surface of the facade elements 1 extends substantially in the same plane when mounted. List of reference numerals

1. Facade elements

2. Screws

3. Horizontal mounting rails

4. Building fagade

5. Vertical mounting rails

6. Windproof sheet material

7. Fire barrier

8. Ventilated cavity

9. Intumescent layer

10. Outer surface of the building fagade

11. Layer of flexible, non-combustible material

12. Clips

13. Upper hook

14. Upward facing edge of horizontal mounting rail

15. C-shaped body

16. Distance member

17. Inner surface of fagade element

18. Lower protrusion of horizontal mounting rail

19. Biasing arm

20. Fagade mounting fastener

21. Upward facing part of horizontal mounting rail

22. Fire barrier rail