EP4332317A1

EP4332317A1 - Fire-break protection system for a ventilation cavity

Info

Publication number: EP4332317A1
Application number: EP23190879.9A
Authority: EP
Inventors: Ruggero ANTONINI
Original assignee: Service Precast Srl
Current assignee: Service Precast Srl
Priority date: 2022-09-05
Filing date: 2023-08-10
Publication date: 2024-03-06

Abstract

Fire-break protection system (1) for a ventilation cavity (104) of a ventilated facade (100) of a building, comprising:
- a shutter body (2) coupled to a ventilation opening (106) obtained in a fastening element (105) of the ventilated facade (100);
- a sacrificial element (3) which mechanically connects the shutter body (2) to the fastening element (105) so that, in absence of fire, the shutter body (2) leaves open the ventilation opening (106),
wherein the sacrificial element (3) is structured to, in case of fire, self-destroying and allow a displacement of the shutter body (2) towards the fastening element (105) along a trajectory having a vertical component for completely shuttering the opening of ventilation (106).

Description

Technical field of the invention

The present invention relates to a fire-break protection system for a ventilation cavity of a ventilated facade of a building.

State of the art

In the field of building design it is known to create ventilated facades (or walls) which typically comprise a plurality of aesthetic panels which create an aesthetic covering of a wall of the building. Typically, the wall of the building is in turn covered with a thermal insulation, i.e. a system of panels that covers the external face of the masonry of the wall for giving the desired thermal insulation. The ventilated facade is characterized by the fact that between the aesthetic covering and the external face of the wall (e.g., of the thermal insulation) there is a ventilation cavity (or gap) inside which air naturally circulates due to the convective motion allowed by the presence of openings at the base and top of the ventilated facade.
A well-known drawback associated with ventilated facades is the fact that, in case of fire, the ventilation cavity behaves in a similar way to the flue of a chimney, favoring the propagation of the heat, fire and/or smoke towards the upper floors. In order to limit the diffusion of heat, fire and/or smoke, it is therefore known to install fire-break protection systems inside the ventilation cavity.
Document US10570613B2 discloses a known fire-break protection system.

Summary of the invention

The Applicant has realized that the known fire-break protection systems have some drawbacks and/or can be improved in some aspects.
For example, the fire-break protection system described in US10570613B2 comprises a shutter element made of thermally insulating material and a movement system which, in case of fire, moves the shutter element horizontally to occupy the ventilation cavity so as to slow down and/or or avoid the propagation of fire. This system requires that a slot be made in the wall (e.g., in the thermal insulation) of the building for housing the shutter element (and its movement system) in normal conditions (in absence of fire).
The Applicant has realized that the realization of this slot involves, on the one hand, an increase in work during the installation of the fire-break protection system (and/or the realization of the thermal insulation), and, on the other, a decrease of the insulating capacity of the thermal insulation with consequent energy waste (e.g., due to the generation of thermal bridges).
In this context, the Applicant has therefore faced the problem of realizing a fire-break protection system which can be installed simply and quickly and/or without causing a deterioration of the insulating capacity of the thermal insulation.
According to the Applicant, the above problem is solved by a fire-break protection system in accordance with the attached claims and/or having one or more of the following characteristics.
According to an aspect the invention relates to a fire-break protection system for a ventilation cavity of a ventilated facade of a building.
Preferably said fire-break protection system comprises:

a shutter body coupled to (at least) a ventilation opening obtained in a fastening element of said ventilated facade;
a sacrificial element which mechanically connects said shutter body to said fastening element so that, in absence of fire, said shutter body leaves open said ventilation opening, wherein said sacrificial element is structured for, in case of fire, self-destroying and allow a displacement of said shutter body towards said fastening element along a trajectory having a vertical component, for completely shuttering said ventilation opening.

According to an aspect the invention relates to a building comprising a ventilated facade having a ventilation cavity and the fire-break protection system of the present invention installed in the ventilation cavity.
The Applicant has realized that the fire-break protection system of the present invention can be advantageously used in combination with the fastening element of the ventilated facade having the function, in cooperation with an appropriate bracket system, for fastening the aesthetic panels of the ventilated facade to the masonry of the wall of the building. During the normal use in absence of fire, the shutter body is coupled to the opening (or, more tipically, the openings) of ventilation of the fastening element, with the sacrificial element which acts as spacer between the shutter body and the ventilation opening so as to leave open the ventilation opening and to allow the passage of air into the ventilation cavity. In case of fire, the destruction of the sacrificial element causes the displacement of the shutter body towards the fastening element so as to completely shutter the ventilation opening and thus avoid the propagation of the fire. In this way the fire-break protection system (in particular the movable shutter body) is overall compact. In use, the fastening element typically is located substantially entirely within the space defined by the ventilation cavity. The displacement of the shutter body along a trajectory having a vertical component advantageously allows the shutter body (in addition to the sacrificial element) to be kept entirely into the ventilation cavity of the ventilated facade, both in case of fire and in absence of fire. The fire-break protection system of the present invention can therefore be installed entirely in the ventilation cavity of the ventilated facade. This allows to avoid carrying out onerous work on the thermal insulation (or in general on the wall) dedicated to obtaining a slot for housing the shutter body, avoiding both an increase in work during installation of the fire-break protection system and a decrease in capacity insulation of the thermal insulation, as no substantial interruptions of continuity (and therefore thermal bridges) are created between the insulating panels of the thermal insulation.
The present invention in one or more of the above aspects may have one or more of the following preferred features.
Typically said fastening element comprises a plurality of ventilation openings aligned, preferably at a (substantially) constant step, along a horizontal main development direction of said fastening element (said shutter body, in absence of fire, leaving open said ventilation openings and, in case of fire, by completely shuttering said ventilation openings). In this way the passage of air inside the ventilation cavity is realized in an effective and/or rational way along the horizontal extension of the ventilation cavity. Typically said fastening element as a whole occupies in plan a whole horizontal section of said ventilation cavity (without considering said ventilation opening(s)). For example, said fastening element comprises a plate-like portion (lying on a horizontal plane) equipped with said ventilation opening(s) and which as a whole occupies in plan a whole horizontal section of said ventilation cavity (with said shutter body moved towards said plate-like portion for completely shuttering said ventilation opening(s). In this way, when the shutter body, in case of fire, shutters the ventilation opening(s), the assembly comprising the fastening element (e.g., the plate-like portion) and the shutter body completely shutters the ventilation cavity, creating a fire-break barrier.
Preferably said shutter body is vertically aligned with said ventilation opening(s). Preferably said trajectory is purely vertical. In this way, in case of fire, reliable and/or efficient movement of the shutter body is obtained (e.g., with reduction, or absence, of friction). For example, rapid shuttering of the ventilation opening(s) is favoured since, at the same speed of movement, a purely vertical trajectory is shorter than any oblique trajectory.
Preferably said sacrificial element is interposed (in contact) between said shutter body and said fastening element (e.g., said plate-like portion). Preferably said sacrificial element is below of said shutter body. Preferably said displacement of said shutter body towards said fastening element is down directed. In other words, the destruction of the sacrificial element causes the shutter body to fall by gravity towards the ventilation opening(s). This makes the presence of a dedicated movement system superfluous which, in case of fire, actively moves the shutter body, since the force of gravity is advantageously exploited. In this way the structure of the fire-break protection system is simple, as it is possible not to provide a dedicated movement system, and/or the functioning of the fire-break protection system is highly reliable, as the risk of breakage/malfunctioning of the movement system is deleted.
Said shutter body can comprise a plurality of shutter sub-bodies aligned along said horizontal main development direction of the fastening element (each shutter sub-body being coupled to one or more ventilation openings). Said sacrificial element can comprise a plurality of sacrificial sub-elements distributed along said horizontal main development direction of the fastening element. Preferably said shutter body (preferably each shutter sub-body) has two or more sacrificial sub-elements associated therewith. This improves the stability of the shutter body during the normal use in absence of fire of the fire-break protection system.
Preferably a distance between two consecutive sacrificial sub-elements, along said horizontal main development direction, is constant and preferably greater than or equal to 50 cm, more preferably greater than or equal to 60 cm, and/or less than or equal to 150 cm, more preferably less than or equal to 120 cm. This provides an appropriate number of sacrificial sub-elements, limiting the material needed and/or the related costs. Preferably said shutter body (or each shutter sub-body) has shape of lath, preferably straight. Preferably said shutter body (or each shutter sub-body) is rigid. In this way the shutter body has a rational shape which, for example, adapts to the typical arrangement of the ventilation openings, simplifying the installation of the fire-break protection system. Preferably said shutter body (or each shutter sub-body) is made of a fire-resistant material. In this way the shutter body does not deteriorate and/or disintegrate under the action of fire.
Preferably said fire-resistant material, according to the EN 13501-1 standard, falls within class A1 or class A2, more preferably also in subclass s1 or s2 (as regards the smoke emission) and/or in subclass d0 or d1 (regarding the production of incandescent droplets or particles). The Applicant has realized that these materials are particularly suitable for making the shutter body.
Preferably said shutter body is (entirely) made of fiber cement and/or metal (e.g., galvanized iron, steel, cast iron, etc.). The Applicant has realized that these materials, in particular the fiber cement and the galvanized iron, have good fire-resistance properties. Furthermore, these materials, in particular the metallic material, give the shutter body a sufficient weight in order to limit the risk that, in case of fire, the smoke and/or air present in the ventilation cavity will overcome (e.g., a due to the vertical chimney effect) the weight force of the shutter body, lifting it from the position in which it shutters the ventilation opening(s).
In one embodiment said fire-break protection system comprises a thrust element mechanically connected to said shutter body for pushing said shutter body towards said fastening element. In other words, the thrust element always keeps the shutter body in a thrust towards the fastening element (this thrust, in one embodiment, being additional to the aforementioned gravitational thrust given by the weight force of the shutter body itself): in absence of fire, the sacrificial element opposes this thrust. In this way the reliability of the fire-break protection system is increased, in particular in terms of shuttering of the ventilation openings. The Applicant has in fact realized that the thrust element allows to further reduce the aforementioned risk of lifting of the shutter body from the position in which it shutters the ventilation opening(s) due to the vertical chimney effect.
Preferably said thrust element is integrated in said shutter body or superimposed (preferably in contact) on said shutter body. In this way the action of the thrust element acts in accordance with the force of gravity, favouring the downward displacement of the shutter body.
Said thrust element may comprise a plurality of thrust sub-elements. Preferably each thrust sub-element is mechanically connected to at least one respective shutter sub-body. Preferably said thrust element (or each thrust sub-element) has shape of lath, more preferably in metallic material (e.g., iron, steel, cast iron, etc.). Preferably, in this embodiment, each shutter sub-body is mechanically connected to one and only one respective thrust sub-element.
In an alternative embodiment said thrust element (or each thrust sub-element) comprises (more preferably is) an elastic element (e.g., a spring) preloaded (in traction or compression), preferably along the vertical direction, in presence of said sacrificial element, so that, after said self-destruction of the sacrificial element, the elastic element at least partly recovers its own rest length. Preferably, in this embodiment, each shutter sub-body is mechanically connected to a plurality of respective thrust sub-elements. Preferably said sacrificial element is made of a combustible material. In this way it is possible to favour a rapid destruction of the sacrificial element in order to promptly shutter the ventilation openings and avoid the propagation of the fire.
Preferably said combustible material, according to the EN 13501-1 standard, falls within class E or class D, more preferably in class E. The Applicant has realized that the materials falling within these classes, when exposed to the fire and/or the heat, have a degradation kinetics suitable for the application of the present invention.
Preferably said sacrificial element is made of expanded polystyrene (EPS). The Applicant has realized that the EPS exhibits, when exposed to the fire and/or the heat, a degradation kinetics (e.g., by melting and/or combustion) particularly suitable for the use in the present invention.

Brief description of the drawings

Figure 1 schematically shows, not to scale, and partially a perspective view of a ventilated facade of a building having a fire-break protection system according to the present invention installed in the ventilation cavity;
figure 2 schematically shows, not to scale, and in a partial way a perspective view of the fire-break protection system according to an embodiment of the present invention;
figures 3-4 schematically show a lateral view in section of the ventilated facade of figure 1 in which the fire-break protection system of figure 2 is installed and in which the shutter body of the fire-break protection system, respectively, leaves open and shutters the ventilation openings;
figure 5 schematically shows a lateral view in section of the ventilated facade of figure 1 in which a fire-break protection system according to a further embodiment of the present invention is installed.

Detailed description of some embodiments of the invention

The characteristics and the advantages of the present invention will be further clarified by the following detailed description of some embodiments, presented by way of example and non-limiting of the present invention, with reference to the attached figures.
In the figures with the reference number 100 it is indicated a ventilated facade comprising a plurality of aesthetic panels 101 (in the figures only one aesthetic panel is shown for simplicity of representation) which create an aesthetic covering of a masonry wall 102 of a building (not shown). Exemplarily the wall 102 is in turn covered by a thermal insulation 103 (shown in a purely schematic way) comprising a plurality of thermally insulating panels (not shown in detail) which cover an external face (i.e., facing the outside of the building) of the wall 102 (in this way the desired thermal insulation is obtained).
The ventilated façade 100 comprises a ventilation cavity 104 which is formed between the aesthetic panels 101 and the external face of the thermal insulation 103. For example, the ventilation cavity 104 has width (along a direction perpendicular to the external face of the wall) comprising in the range 30 mm - 50 mm.
In order to allow the installation of the aesthetic panels 101 to the wall 102, a fastening element 105 is provided. Exemplarily, the fastening element 105 is made of metallic material, for example aluminium.
Typically the fastening element 105 comprises a plurality (not shown) of fastening sub-elements 105', which are exemplarily arranged aligned in sequence along a horizontal direction 200. Typically the fastening element 105, with the respective associated elements of the fire-break protection system, is replicated at a plurality of discrete elevations vertically distributed along the facade (not shown).
For simplicity of representation, only one fastening sub-element 105' is shown in the figures. This fastening sub-element 105' for example (as schematically shown in figure 1) can fasten (e.g., by means of screws) a single aesthetic panel 101, or (not shown) is between two vertically or horizontally side by side panels. A bracket system 110 (e.g., L-shaped brackets) also contributes exemplarily to the installation of the aesthetic panels 101, which allows the fastening of the fastening sub-elements 105' to the masonry of the wall 102 without causing substantial discontinuities inside the thermal insulation 103. For example, the bracket system 110 comprises a plurality of first brackets 110' (of which only one is shown for simplicity of representation) which extend vertically along the entire extension of the ventilated facade 100 and which are exemplarily distributed discretely, for example at regular intervals, along the horizontal extension of the ventilated facade 100. Alternatively, each first bracket 110' may comprise a plurality of vertically aligned sub-brackets. The first brackets 110' are mechanically connected (e.g., by screws) to the fastening sub-elements 105'.
The bracket system 110 also comprises exemplarily, for each first bracket 110', a respective plurality of second brackets 110" (of which only one is shown for simplicity of representation) distributed along the vertical extension of the ventilated facade 100 and which mechanically connect the first bracket 110' (or a respective sub-bracket if the first bracket 110' is not a single body) to the masonry of the wall 102.
On each fastening sub-element 105' there is exemplarily obtained a plurality of ventilation openings 106, which are aligned along the horizontal main development direction 200 of the fastening sub-element 105'.
Exemplarily the ventilation openings 106 are aligned with a constant step, equal for example to about 30 mm (this step typically having a value comprises between 10 mm and 50 mm). Exemplarily the ventilation openings 106 have elliptical shape with surface area equal for example to about 300 mm² (this area typically having value comprises between 100 mm² and 500 mm²).
Typically, the ventilation openings 106 are obtained on a plate-like portion 107 of the fastening sub-element 105' lying on a horizontal plane. Typically, the plate-like portion 107 as a whole occupies in plan a whole horizontal section of the ventilation cavity 104, ignoring the ventilation openings 106.
For example, the fastening sub-element 105' (as shown in the figures) can have two plate-like portions 107 and 107', flat and parallel to each other, connected by a vertical portion 108. In any case, the present invention contemplates the use of fastening sub-elements of any shape. For example (not shown, but of known type) the fastening sub-element can have a structure with shape similar to a "z" in the section perpendicular to the direction 200, with a single plate-like portion (equipped with openings), flat and horizontal, and two vertical portions on opposite sides and at opposite ends of that horizontal portion.
With reference to the figures 2-5, a fire-break protection system 1 according to the present invention installed in the ventilation cavity 104 of the ventilated facade 100 is described, in particular coupled to the ventilation openings 106 of the fastening element 105.
The fire-break protection system 1 comprises a shutter body 2 exemplarily vertically aligned with the ventilation openings 106.
Exemplarily the shutter body 2 comprises a plurality of shutter sub-bodies 2' aligned along the horizontal main development direction 200 of the fastening element 105, with each shutter sub-body 2' vertically aligned for example with a predefined number of openings ventilation 106. In the figures, for simplicity of representation, only one shutter sub-body 2' is shown.
Exemplarily each shutter sub-body 2' is rigid, and exemplarily has shape of straight lath (e.g., having constant section of square or rectangular shape). Exemplarily each straight lath 2' has a length (along the horizontal direction 200) equal to about 240 cm or 300 cm. Typically each shutter sub-body 2' is made of a fire-resistant material, such as fiber cement or a metal (or metal alloy) such as the galvanized iron. The Applicant has realized that the fiber cement or the galvanized iron are particularly advantageous for the purposes of the present invention since, according to the EN 13501-1 standard, they fall into class A2, subclass s1 (as regards the smoke emission) and subclass d0 (as regards the production of incandescent droplets or particles).
The fire-break protection system 1 also comprises a sacrificial element 3 exemplarily interposed in contact between the shutter body 2 and the fastening element 105 (e.g., the plate-like portion 107), with preferably the sacrificial element 3 below of the shutter body 2 (in other words which acts as support for the shutter body).
Exemplarily, the sacrificial element 3 comprises a plurality of discrete sacrificial sub-elements 3', distributed along the horizontal main development direction 200 of the fastening element 105. Exemplarily, a distance between two consecutive sacrificial sub-elements 3', along the horizontal main development direction 200, is constant and for example equal to about 80 cm or 100 cm.
Exemplarily, each sacrificial sub-element 3' has shape of parallelepiped having base area equal, for example, to about 400 mm² (for example, square base with side of 20 mm) and thickness equal, for example, to about 10 mm.
Exemplarily, each sacrificial sub-element 3' is made of a combustible and/or meltable material, preferably expanded polystyrene (EPS). The Applicant has realized that this material has a degradation kinetics particularly suitable for the application of the present invention since, according to the EN 13501-1 standard, it falls within class E.
In one embodiment (as shown in the figures) the fire-break protection system 1 also comprises a thrust element 4 mechanically connected (e.g., by means of suitable mechanical fastening means) to the shutter body 1.
Exemplarily, the thrust element 4 comprises a plurality of thrust sub-elements 4', each thrust sub-element 4' being exemplarily mechanically connected to a respective shutter sub-body 2'. In the figures, for simplicity of representation, only one thrust sub-element 4' is shown.
Exemplarily, each thrust sub-element 4' is superimposed in contact with the respective shutter sub-body 2'. Alternatively, the thrust element (or each sub-thrust element) can for example consist of metal bars incorporated in the fiber cement lath.
In the embodiment of figure 2-4, each thrust sub-element 4' has shape of straight lath, for example in iron, and is fixed to the respective shutter sub-body 2' for example by means of suitable screws.
In the embodiment shown in figure 5, each thrust sub-element 4' is a preloaded spring, for example in compression, along the vertical direction, which is mechanically attested at a first end to the upper face of the shutter sub-body 2'. Exemplarily, each spring 4' is also fastened at a second end to the first bracket 110' by means of suitable mechanical fastening means 20 (e.g., a respective L-shaped plate screwed to the first bracket 110'). Typically, in this embodiment, each shutter sub-body 2' is mechanically connected to more than one spring 4'.
In an embodiment not shown, the spring is preloaded in traction and the sacrificial element is arranged, instead of under the shutter body, above it, for example interposed between the shutter body and the upper plate-like portion. In this case the movement of the shutter body, in case of fire, takes place vertically upwards under the only thrust of the spring (the gravity opposes this movement).
In a preferred embodiment (not shown), the fire-break protection system is devoid of thrust element. This is advantageously possible when the shutter body 2 has sufficient weight to allow the shuttering of the ventilation openings even in presence of the chimney effect. This occurs, for example, when the shutter body 2 is made of metal or metal alloys (e.g., galvanized iron).
As schematically shown in figure 3 and figure 5, in absence of fire, the sacrificial element 3 acts as a spacer (as well as a support element) to ensure that the shutter body 2 leaves open the ventilation openings 106, allowing the passage of air in the ventilation cavity 104 (represented schematically by the arrows).
As schematically shown in figure 4, in case of fire, the sacrificial element 3 is destroyed and allows a vertical displacement (i.e., a fall due to gravity) of the shutter body 2 towards the fastening element 105 (e.g., the plate-like portion 107) for completely shuttering the ventilation openings 106. In this way the entire horizontal section of the ventilation cavity is shuttered.
As explained above, the destruction of the sacrificial element 3 causes the shutter body 2 to fall due to gravity.
In the embodiments provided with a thrust element 4 additional to the shutter body 2, the gravitational thrust given by the weight force of the shutter body 2 is assisted by the thrust generated by the thrust element 4 which generates a thrust in accordance with the force of gravity. In fact, following the destruction of the sacrificial element 3, in the embodiment of figure 2-4 the weight force of the thrust element 4 is added to the weight force of the shutter body 2, while in the embodiment of figure 5 the spring at least partially recovers its own rest length generating a vertical and downward elastic force.

Claims

Fire-break protection system (1) for a ventilation cavity (104) of a ventilated facade (100) of a building, wherein said fire-break protection system (1) comprises:
- a shutter body (2) coupled to a ventilation opening (106) obtained in a fastening element (105) of said ventilated facade (100);

- a sacrificial element (3) which mechanically connects said shutter body (2) to said fastening element (105) so that, in absence of fire, said shutter body (2) leaves open said ventilation opening (106),
wherein said sacrificial element (3) is structured for self-destroying in case of fire, and allow a displacement of said shutter body (2) towards said fastening element (105) along a trajectory having a vertical component for completely shuttering said ventilation opening (106).
Protection system (1) according to claim 1, wherein said shutter body (2) is vertically aligned with said ventilation opening, and wherein said trajectory is purely vertical.
Protection system (1) according to any one of the preceding claims, wherein said sacrificial element (3) is interposed between said shutter body (2) and said fastening element (105) and said sacrificial element (3) is below of said shutter body (2), and wherein said displacement of said shutter body (2) towards said fastening element (3) is down directed.
Protection system (1) according to any one of the preceding claims, wherein said shutter body (2) has shape of straight lath and it is made of a fire-resistant material which, according to EN 13501-1 standard, falls within class A1 or class A2, preferably also in subclass s1 or s2 and in subclass d0 or d1.
Protection system (1) according to any one of the preceding claims, wherein said shutter body (2) is made of fiber-cement and/or metal.
Protection system (1) according to any one of the preceding claims, wherein said sacrificial element (3) is made of a combustible material which, according to EN 13501-1 standard, falls within class E or class D, and wherein said sacrificial element (3) is made of expanded polystyrene (EPS).
Protection system (1) according to any one of the preceding claims, wherein said sacrificial element (3) comprises a plurality of sacrificial sub-elements (3') distributed along a horizontal main development direction (200) of the fastening element (105), wherein said shutter body (2) has associated two or more sacrificial sub-elements (3'), and wherein a distance between two consecutive sacrificial sub-elements (3'), along said horizontal main development direction (200), is constant and greater than or equal to 50 cm and less than or equal to 150 cm.
Protection system (1) according to any one of the preceding claims, comprising a thrust element (4) mechanically connected to said shutter body (2) for pushing said shutter body (2) towards said fastening element (105), wherein said thrust element (4) is superimposed on said shutter body (2), and wherein said thrust element (4):
- has shape of lath made of metal material, or

- comprises an elastic element preloaded along a vertical direction (201) in presence of said sacrificial element (3), so that, after said self-destruction of the sacrificial element (3), the elastic element at least partially recovers its own rest length.
Protection system (1) according to any one of the preceding claims, wherein said fastening element (105) comprises a plurality of ventilation openings (106) aligned along a horizontal main development direction (200) of said fastening element (105), wherein said fastening element (105) comprises a plate-like portion (107) equipped with said ventilation opening/s and wherein said plate-like portion (107), as a whole, occupies in plan a whole horizontal section of said ventilation cavity (104), and wherein said shutter body (2) is vertically aligned with said ventilation openings.
Building comprising a ventilated facade (100) having a ventilation cavity (104) and the fire-break protection system (1) according to any one of the preceding claims installed in the ventilation cavity (104).