Method for functionalizing a roofing device, and resultant roofing device

Abstract

The invention relates to a method for functionalizing a roofing device (1), while at least maintaining and preferably increasing its fire resistance, said roofing device (1) comprising, at least, a sealing membrane or similar sealing system (2), previously or newly installed either directly on a roofing support or substrate (3) or on a functional layer (4) placed on this support or substrate (3), this sealing membrane or similar sealing system (2) forming a first layer. The system obtained is characterized in that it consists in applying at least one adhesion base layer (5) which comprises at least one intumescent material (6), and subsequently applying at least one additional layer (7) to the at least one base layer (5), said additional layer forming an upper functional layer (7') after drying.

Description

Description Title of the invention: Method for functionalizing a roofing device and resulting roofing device

[0001] The present invention relates to the field of roof covering systems and functionalized roofing devices, more specifically in relation to systems of complex laminated layers incorporating a liquid sealant or a functionalized top layer of another type, and has as its objects a method of functionalizing a roofing device with preservation, or even increase of its fire resistance, as well as a resulting functionalized roofing device.

[0002] Protecting buildings, houses, and similar structures from fire, particularly from external fires, is a constant concern for builders and is subject to strict regulations. Roofs in particular have a classification system in Europe in accordance with the EN 13501-5:2016 standard.

[0003] In the field of construction, the use and operating method of an intumescent material, or material that expands under the effect of heat, to protect a support that it covers, are well known to those skilled in the art.

[0004] This type of material is for example incorporated into paints or varnishes which can coat structural elements made of wood, metal or concrete, or for example incorporated into a top protective coating layer applied to roofing products, as disclosed by document WO 2005 / 067470.

[0005] It is also known, for example from document WO 03 / 006109, to integrate such an intumescent material into a product forming a fire-resistant barrier, such as a curtain intended to subdivide the interior space under the framework, or possibly to cover it with it. This curtain is fixed, with an adhesive also integrating an intumescent material, to structural elements of the framework.

[0006] Document WO 2017 / 197136 also discloses a prefabricated, multi-layer composite thermoplastic membrane comprising two sheets of thermoplastic material between which a layer is sandwiched reinforcement and to which are attached a layer of expandable graphite and a support layer.

[0007] Document US 11,060,290 also discloses a multi-layer construction panel with a central layer based on fragments of paper and polypropylene bonded by polyethylene, this central layer being covered on one side by a glass fiber felt incorporating an intumescent material and on the other side by a sheet of paper (the two outer layers being laminated by a polyethylene-based adhesive). To create a waterproof system on site, this panel is covered with a waterproof membrane.

[0008] The prefabricated products disclosed by these two documents are complex and expensive, are tedious to install on site and are generally "oversized", in terms of the number of layers, for restoration work or additional work (aimed at providing fire resistance properties) on existing roofs already provided with waterproofing.

[0009] In addition, roof waterproofing processes are also known, in the context of new roof constructions or restoration sites, by implementing a liquid waterproofing in association with a previously applied primer layer, and which make it possible to obtain a continuous waterproofing without surface joints, possibly in addition to the initial waterproofing present, possibly defective or at least with joints.

[0010] Furthermore, methods are known for giving the visible surface of the roof an additional functionality, of a technical or non-technical nature, by adding an additional functional layer (for example with surface radiative properties, for decorative or informative purposes, with increased resistance to climatic agents and / or the effects of pollution). However, the addition of such a surface layer may, in particular given the often at least partially organic nature of its constituent material, lead to a reduction in the fire resistance of the roofing device concerned.

[0011] Taking into account the state of the art set out above, the person skilled in the art, faced with the problem of preserving or even (preferably) improving the fire resistance of a roofing device comprising a liquid waterproofing layer or a layer otherwise functionalized on the surface, could be encouraged to integrate such an intumescent material either i) in the surface layer, or ii) in at least one underlying layer in combination with another component having particular fire resistance properties, or iii) in all the layers of the laminated complex formed by these layers.

[0012] However, the first option (i) is likely to compromise the sealing or other functional performance, and also to degrade the visual appearance, of the exposed top layer.

[0013] The second option ii), and even more so the third option iii), entail the need to provide two / three components / layers with fire resistance properties, which complicates and increases the cost of the roofing system, and also limits the range of usable products, as well as the conditions of implementation, in particular in relation to existing waterproofing.

[0014] Furthermore, there is also a constant demand and research, particularly from manufacturers, to provide processes and systems that meet, in terms of resources and costs, as closely as possible the requirements of the applicable standards, namely, in the given context, to obtain or at least maintain a required classification (possibly minimum) in relation to the aforementioned standard, without compromising the waterproofing or other functionality properties, nor impacting the final appearance of the top layer. Furthermore, additional operations should be avoided and modifications to the already existing products used should be limited.

[0015] Thus, the present invention aims to propose a method for functionalizing a roofing device with at least preservation, and preferably improvement, of its fire resistance (compared to the same device without the functionality) and simultaneously making it possible to overcome the disadvantages of the three options considered above, while being able to easily meet the request formulated.

[0016] This aim is achieved by the invention thanks to a method of functionalizing a roofing device, with at least maintaining and preferably increasing its fire resistance, said roofing device comprising, at least, a bituminous waterproofing membrane or a similar waterproofing system, previously laid or having just been laid either directly on a support or substrate roofing, or on a functional layer placed on this support or substrate, this waterproofing membrane or this similar waterproofing system forming a first layer, a method characterized in that it comprises the steps consisting of: - applying, on at least part of the surface of said waterproofing membrane or said similar waterproofing system, at least one base or bonding layer which comprises at least one intumescent material as an additive, this base layer forming a second intermediate layer and consisting of a bonding primer; - then applying at least one additional layer on said at least one base layer, this or these additional layer(s) constituting after drying a functional upper layer, or third layer, and preferably not having increased or particular fire resistance properties, the first, second and third layers thus forming a multi-layer laminated complex and the base layer forming an intermediate layer between the aforementioned first and third layers, and it alone, comprising at least one intumescent material as an additive and also having barrier functions to migrations between the first and third layers.

[0017] Indeed, the inventors found unexpectedly and surprisingly that the incorporation of intumescent material exclusively in the single intermediate primer layer (layer applied directly to the first existing layer) gave the entire multi-layer laminate complex particular properties of resistance to external fire, independently of the characteristics of the at least two other layers of the laminate complex, which may not have any particular fire resistance properties and may in particular be made from existing unmodified materials.This unique integration of intumescent material precisely in the single layer of primer mentioned above can also allow, possibly by quantitative adjustment of intumescent material, the laminated complex to present fire resistance properties resulting in a desired or required exterior fire performance classification, with limited additional cost and reduced implementation complexity.

[0018] The inventors also found that despite the addition of such an intumescent material, in a quantity just sufficient to obtain the targeted regulatory performances, the performances of the other functions of the primer of such a system, namely promoting the adhesion of the functionalized upper layer to the first lower layer (particular adhesion function) and preventing migrations between this lower layer and the functionalized upper layer (barrier function), were substantially preserved (compared to the same unmodified primer).

[0019] The invention will be better understood from the following description, which relates to preferred embodiments, given as non-limiting examples, and explained with reference to the appended schematic drawings, in which:

[0020] [Fig. 1] is a schematic sectional and elevational view of a multi-layer laminated complex (here three-layer) obtained by implementing the method according to the invention and forming part of a functionalized roofing device, and,

[0021] [Fig. 2] is a stepped and perspective sectional view of a functionalized roofing device according to one embodiment of the invention, comprising a multi-layer laminated complex as shown in Figure 1.

[0022] Thus, the present invention relates to a method for functionalizing a roofing device 1, with at least maintaining and preferably increasing its fire resistance, said roofing device 1 comprising, at least, a bituminous waterproofing membrane or a similar waterproofing system 2, previously laid or having just been laid either directly on a roofing support or substrate 3, or on a functional layer 4 laid on this support or substrate 3, this waterproofing membrane or this similar waterproofing system 2 forming a first layer. By "analogous waterproofing system" in relation to the existing first layer 2, is meant in particular in the present a waterproofing system formed of a single bituminous waterproofing membrane or of several superimposed bituminous waterproofing membranes, or a waterproofing complex comprising a bituminous waterproofing membrane on the surface.

[0023] According to the invention, this method is characterized in that it comprises the steps consisting of: - applying, on at least part of the surface of said waterproofing membrane or said similar waterproofing system 2, at least one base or bonding layer 5 which comprises at least one intumescent material 6 as an additive, this base layer 5 forming a second intermediate layer and consisting of a bonding primer; - then applying at least one additional layer 7 on said at least one base layer 5, this or these additional layer(s) 7 constituting after drying a functional upper layer 7', or third layer, and preferably not having increased or particular fire resistance properties, the first, second and third layers 2, 5, 7' together forming a multi-layer laminated complex 8 and the base or bonding layer 5 forming an intermediate layer between the aforementioned first and third layers, and it alone, comprising at least one intumescent material as an additive and also having barrier functions to migrations between the first and third layers 2 and 7'.

[0024] Thanks to these different arrangements taken in combination, the invention makes it possible to respond to the request expressed previously and to achieve the set goal.

[0025] The multi-layer laminated complex 8 obtained by implementing the method according to the invention, as visible as an example in FIG. 1, is designed for any type of roofing device 1 to be functionalized, such as a sloping roof or a flat roof called a terrace, in particular also roofs of residential buildings or establishments receiving the public.

[0026] According to the invention, the expression "fire resistance properties" means that the spread of an external fire on a multi-layer laminated complex 8 of the type concerned remains limited to the surface and depth of the material(s) constituting the multi-layer laminated complex 8, this over a sufficiently long period to prevent the fire from reaching neighboring parts and entering the dwelling. For the purposes of the invention, the "fire resistance property" is governed by standard NF EN 13501-5 by implementing one of the four test methods 3 described in NF EN 1187 to determine an external fire performance class defining a fire resistance over time, over a fire propagation distance in the depth and on the surface of the system. For example, BROOF class t3 is given using test method 3 and for a system with an external fire propagation time (TE) > 30 minutes, and a fire penetration time (Tp) > 30 minutes.

[0027] The TE value, defined by standard NF EN 13501-5, corresponds to the external propagation time of the fire during the test upwards and downwards, expressed in maximum burnt length, from the projection edges of the brands on the exposed surface.

[0028] The Tp value, defined by standard NF EN 13501-5, corresponds to the time of fire penetration until the appearance of flaming elements on the lower layer of the entire system.

[0029] When the roofing device 1 already has, before application of the functionalization method according to the invention, sufficient fire resistance due to its own covering layers, the invention may aim to at least maintain this level of resistance (and therefore compensate for the loss or reduction in fire resistance resulting from the functionalization), or even to improve it to meet the aforementioned standard. However, in the event of the absence of particular fire resistance of the roofing device before application of the functionalization method, or insufficient fire resistance, the functionalization method according to the invention may advantageously contribute to increasing this resistance, in particular so that the functionalized roofing device has fire resistance meeting the standard.

[0030] As illustrated by way of example in Figure 1, the multi-layer laminated complex 8 according to the invention, obtained by means of the method mentioned above, comprises: a first lower layer 2 of the waterproofing membrane type or similar waterproofing system, a second intermediate layer 5 of the base or bonding layer type and a third functional upper layer 7'.

[0031] In the present application, the term “waterproofing system 2” is understood to mean in particular a system formed of at least two superimposed bituminous waterproofing layers, in particular two superimposed bituminous membranes, whether identical or not.

[0032] The base layer 5 is of the type capable of providing the desired adhesion to the surface of the first layer 2 for the upper layer 7'. It may consist of a so-called primer material, advantageously also having barrier functions to migrations between the first and third layers 2 and 7' (from 2 to 7, 7'). The migrations prevented from the lower layer to the upper layer are those of substances originating from the bituminous binder (oils, additives or others) of the first layer and capable of altering the properties or functionalities of the third layer or of locally modifying at least its color.

[0033] Although not imperative, it may be provided, in the context of an application taking full advantage of the advantages of the invention, that the functional upper layer 7' advantageously does not have a physicochemical constitution or a composition giving it increased or particular fire resistance properties. This layer 7' may even, on the contrary, be easily combustible and thus, if necessary, tend to degrade the possible fire resistance properties of the roofing device 1, this possible degradation being largely compensated, or even overcompensated, by the beneficial effects resulting from the provisions of the method of the invention.

[0034] Preferably, it is provided that the waterproofing membrane or similar waterproofing system 2 - forming the first lower layer of the multi-layer laminated complex 8 -, on the one hand, and the - third - functional upper layer 7', on the other hand, have mutually different physicochemical constitutions or are mainly based on materials having mutually different physicochemical constitutions. In addition, the two aforementioned layers 2 and 7', as well as, where appropriate, the functional layer 4 possibly present, advantageously do not have a physicochemical constitution or a composition giving them increased or particular fire resistance properties, that is to say that they have a physicochemical constitution or a composition not giving them increased or particular fire resistance properties.Alternatively, the functional layer 4 may, however, when present, exhibit fire resistance properties, for example if it is a rock wool insulating layer.

[0035] According to the invention, the term "physicochemical constitutions" of a layer means the entire compound(s) / material(s) chemically and physically constituting said layer. Furthermore, "predominantly" means herein at least 50% by weight of the composition of the materials forming layers 2 and 7' respectively. Furthermore, and in any event, layer 7' does not consist of a layer of prefabricated material of a thermoplastic nature (for example a synthetic waterproofing membrane based on plasticized PVC or polyolefins), and preferably none of the materials of layers 5 and 7' are thermoplastic materials, nor based on such materials.

[0036] The third functional upper layer 7' may have a physical structure resulting from the application of a single layer 7 in one piece or a multi-layer structure in a stratified form resulting from the application of several unitary layers 7. In other words, the third functional upper layer 7' may consist of a single layer or a succession of layers physically arranged on top of each other resulting from layers 7 applied successively with intercalation of drying phases (for example to have shorter drying times).

[0037] In addition, the third functional upper layer 7' may be obtained by applying one or more liquid products of identical or different chemical natures. Said or each liquid product applied may consist of a single compound or a multi-compound composition. The application of the liquid product(s) may be carried out in a single application step or in several successive and distinct steps.

[0038] The entire third functional top layer 7' can be of a single chemical composition with a single liquid product.

[0039] The entirety of the third functional upper layer 7' may alternatively have a chemical composition formed by several liquid products, of different chemical natures, which are structurally arranged in a single-piece mixture or superimposed in strata.

[0040] According to a first embodiment of the method according to the invention, the or each additional layer 7 applied is of the sealing material type liquid, the resulting functional upper layer 7' having, after drying, a continuous surface and a thickness structure (sectional view) in one piece or laminated.

[0041] According to a second embodiment of the method according to the invention, the or each additional layer 7 applied consists of a liquid coating material and the resulting functional upper layer 7' has surface radiative properties, in particular in the wavelengths of solar light (in particular visible and IR), and advantageously has a continuous surface and a single-piece or laminated thickness structure.

[0042] Preferably, the or each additional layer 7 applied consists of a light-colored, for example white, liquid coating material, the resulting functional top layer 7', which has a single-piece or laminated structure, having a solar reflectance index (SRI) greater than 90, preferably greater than 100.

[0043] According to a third embodiment of the method according to the invention, the functional upper layer 7', with a single-piece or laminated structure, is a light-colored, or even white, sealing layer and has a solar reflectance index greater than 90, preferably greater than 100.

[0044] Also in accordance with the invention, and as is apparent from the method mentioned above, the second intermediate layer 5, and only it, comprises at least one intumescent material 6 and the fire resistance properties of said multi-layer laminated complex 8 are conferred solely by the second intermediate layer 5, none of the first and third layers 2 and 7' having a physico-chemical constitution conferring on it particular fire resistance properties.

[0045] In relation to the invention, the term "intumescent material 6" means any material which, under the action of heat, is capable of expanding and swelling, forming a charred or carbonized layer which has the effect of delaying the spread of inflammation to the underlying layers. This charred layer forms a protective barrier which limits the combustion of the material itself by removing the "activation energy" element of the fire triangle. According to the invention, the presence within the intermediate layer 5 of this "intumescent material" intumescent 6” does not in any way alter, in a normal situation (excluding the presence of fire), the functions and physicochemical properties of this intermediate layer 5, nor of the adjacent layers. In particular, the presence of said “intumescent material 6” does not alter the sealing properties of said first lower layer 2, nor the functionalization properties of said third functional upper layer 7'. It also does not affect the functions, for example of adhesion and barrier, of the intermediate layer 5.

[0046] Thus, in a particularly advantageous manner, the multi-layer laminated complex 8 for roofing has the advantageous property, by its specific structural configuration (incorporating in the intermediate layer at least one intumescent material 6) of being, as a whole, resistant to fire and to a rise in temperature of the underlying layers, in order to protect the construction carrying said multi-layer laminated complex 8 (as well as the roofing device 1 comprising it) and the neighboring constructions over a sufficiently long time interval to allow, for example, the evacuation of people and the activation of other means of extinguishing the fire, such as the intervention of the fire brigade.

[0047] According to a preferred embodiment of the invention, and since the fire resistance properties are conferred solely by the second intermediate layer 5, the layers 2 and 7' may be traditional existing layers, unmodified and devoid of any specific fire-resistant properties.

[0048] Indeed, the judicious integration of an intumescent material 6 solely and exclusively in the second intermediate or base layer 5 makes it possible to confer fire resistance properties on the entire multi-layer laminate complex 8. In addition to not deteriorating, before combustion, the respective properties, in particular sealing, of the first layer 2 and the third functional layer 7', the integration of an intumescent material 6 specifically in the second intermediate layer 5 advantageously makes it possible to deploy the fire resistance properties over the entire multi-layer laminate complex 8.

[0049] Thus, the structural configuration of the layers of the multilayer laminated complex 8 of the invention, obtained by the above method, allows the distribution of the fire resistance properties over the entire multi-layer laminate complex 8, by a synergistic effect between the second intermediate layer 5 comprising at least one intumescent material 6, and the adjacent lower 2 and upper functional 7' layers which are not fire resistant. The intumescent material 6 of the intermediate layer 5 impacts the entire multi-layer laminate complex 8, and therefore the roofing device 1 and extends its fire resistance properties over it.

[0050] According to a preferred embodiment of the invention, the intumescent material 6 present in the base layer 5 consists of exfoliating graphite or expandable graphite, preferably present in the form of grains or particles, incorporated into the base material predominantly forming said second intermediate layer 5.

[0051] Expandable graphite is preferred because it has intercalating agents between its layers, which, under the effect of heat, decompose, generating gases, which causes the layers to spread apart and the graphite particles to expand up to 300 times their initial volume. Thus, when exposed to a flame, expandable graphite advantageously produces a layer of insulating expanded graphite on the surface, serving as protection against heat and preventing the diffusion of gaseous decomposition products and fuels that could fuel the flame.

[0052] According to a first particular embodiment, the second intermediate layer 5 is made up of said base material which alone forms the entirety of said layer, such as for example a polyurethane resin, or an epoxy resin, or a PMMA (Poly Methyl Methacrylate) based resin, or a latex composed of an aqueous dispersion of copolymers, or a silane-modified polymer resin.

[0053] According to another embodiment, the second intermediate layer 5 comprises a base material such as a polyurethane resin, or an epoxy resin, or a PMMA-based resin, or a latex composed of an aqueous dispersion of copolymers, or a silane-modified polymer resin mixed with one or more other material(s), in particular for example of the solvent type, plasticizer, rheology additive, anti-foaming agent, leveling additive or mineral filler.

[0054] According to a particular embodiment, the selected base material is a single-component or two-component material.

[0055] Expandable graphite is preferred as intumescent material 6 in the context of the invention because it advantageously has an expansion rate of between 30 and 400 ml / g, preferably 250 to 350 ml / g, under the effect of a starting temperature of between 140°C and 230°C, for a carbon content of between 85% and 99.5% and graphite particle sizes, in the second intermediate layer 5, of between 75 and 500 pm, preferably between 100 and 300 pm. Thus, practically as soon as the fire starts on the surface of the multilayer laminated complex 8, and under the action of heat, the expandable graphite swells (expands) and acts as a fire retardant, while making its fire resistance properties available to at least the layers located under the second intermediate layer 5.

[0056] As intumescent material 6, exfoliating graphite or expandable graphite is preferred in the context of the invention because compared to other fire-retardant mineral substances, such as metal oxides of the aluminum or magnesium hydroxides type, in equal quantity, said graphite has better fire resistance performance and does not alter the mechanical flexibility properties of the intermediate layer 5. Compared to exfoliating or expandable graphites, metal oxides generate undesired water sensitivity and humidity when combined with a base material of the polyurethane resin type. In addition, expanded or exfoliating graphite is non-toxic unlike, for example, known fire-retardant halogenated or melamine compounds.Furthermore, expanded or exfoliating graphite is preferred to fire-retardant liquid materials, such as phosphorus, nitrogen or halogen-based compounds, for its low cost and its compatibility with the other layers of the multi-layer laminate complex (8) of the invention.

[0057] In addition, the intumescent material 6 in the form of grains or particles is preferred because this allows its homogeneous distribution in the thickness of the second intermediate layer 5. Indeed, under the effect of heat, the particles disperse instantly in the second intermediate layer 5 and expand to produce a protective intumescent layer on the surface slowing the spread of fire, gas and smoke.

[0058] A homogeneous distribution of the grains or particles promotes a uniform propagation of the fire resistance properties within the second intermediate layer 5. Advantageously, the uniform fire resistance properties of the second intermediate layer 5 will be transposed, by synergy, across the entire multi-layer laminate complex 8, in particular at the level of the third functional upper layer 7'.

[0059] According to a first advantageous arrangement of the invention, the intumescent material 6 constitutes between 5% and 50%, preferably between approximately 5% and 40%, more preferably between approximately 10% and 30%, and even more preferably between approximately 10% and 20%, by weight of the material (or possible mixture of materials) forming the second intermediate layer 5.

[0060] With an amount of between 5% and 50% by weight of intumescent material 6 relative to the total weight of the material forming the second intermediate layer 5, the fire resistance properties of the complex are sufficient to meet the NF EN 13501-5 standard and enter into at least one of the classes (BROOF, CROOF, DROOF) of this standard. Advantageously, with an amount of between approximately 10% and 20% by weight of intumescent material 6 relative to the total weight of the material forming the second intermediate layer 5, the multilayer laminate complex 8 will have a fire resistance property which is classified as “BROOF t3” by test method 3 of NF EN 1187, in relation to the NF EN 13501-5 standard, which corresponds to the certification required in France.

[0061] According to another advantageous arrangement of the invention, the intumescent material 6 is present in the intermediate layer 5 with a surface mass of between 10 g / m 2and 500 g / m 2 , more preferably between 20 g / m 2 and 250 g / m 2 , and even more preferably between 30 g / m 2 and 150 g / m 2 This second provision, additional or alternative to the first provision, also makes it possible to confer fire resistance properties on the complex which are sufficient to meet the NF EN 13501-5 standard and enter into at least one of the classes (BROOF, CROOF, DROOF) of this standard. Advantageously, with a presence in the intermediate layer 5 in terms of surface mass of between approximately 50 g / m 2 and 100 g / m 2 , the multi-layer laminate complex 8 will have a fire resistance property which is classified as “B ROOF t3”.

[0062] In accordance with another preferred characteristic of the invention, and in particular in relation to the two aforementioned arrangements, the intumescent material 6 is in particulate form with an average particle size advantageously between 75 pm and 500 pm, preferably between 100 pm and 300 pm.

[0063] The integration of the particulate or granular intumescent material 6 into the second intermediate or base layer 5 and applied with a very thin thickness (typically between 0.2 mm and 0.7 mm, preferably of the order of 0.4 mm to 0.5 mm), makes it possible to visually ensure, during application, the presence of said material and its substantially uniform distribution in this layer 5. This ability is further increased when the material of said layer 5 is transparent or at least translucent, at least at the time of its application (avoids non-uniform application, or even the absence in areas, of intumescent material - a defect which can be overcome by mixing the loaded liquid / viscous material before application).

[0064] The integration of the intumescent material 6 into the primer layer forming the intermediate layer 5, with the rate and granulometry mentioned previously, allows this layer to retain, at least very largely and preferably in full, the intrinsic barrier and adhesion properties of the material forming this layer.

[0065] Advantageous choices in terms of types of constituent materials, thicknesses and properties of the layers 2, 5 and 7', in relation to variants of the method and the resulting multi-layer laminate complex 8 according to the invention, are set out below.

[0066] Thus, according to a characteristic of the method and of the multilayer laminated complex 8 of the invention, the base material forming the second intermediate layer 5 is chosen from 1K or 2K polyurethane resins, PMMA (Poly Methyl Methacrylate) based resins, epoxy resins, polymers silane-modified and aqueous dispersions of acrylic, or methacrylic, or urethane, or epoxy polymers or copolymers of these compounds. The choice of the base material forming the second intermediate layer 5 will be made in accordance with the general knowledge of those skilled in the art so as to maintain chemical and structural compatibility with the functional upper layer 7' of the multilayer laminate complex 8.

[0067] According to an advantageous embodiment of the multi-layer laminated complex 8 of the invention and its production method, the third functional upper layer 7' of the liquid sealing type is a combustible layer which has a single-piece or laminated physical structure.

[0068] According to a specific embodiment variant of the aforementioned advantageous embodiment, the third functional upper layer 7' is of organic nature. It advantageously results from the application of at least one layer 7 comprising a material formed from a composition chosen from compositions based on 1K or 2K polyurethane resins, resins based on PMMA (Poly Methyl Methacrylate), epoxy resins, silane-modified polymers, fluorinated or silicone polymers, or aqueous dispersions of acrylic, or methacrylic, or urethane, or epoxy polymers or copolymers of these compounds. The choice of the compositions of the third functional upper layer 7' is made according to the general knowledge of a person skilled in the art and the desired end use or the application envisaged for the multilayer laminate complex 8, in particular the functionalization sought for the roofing device 1.For example, it is possible to choose for the third functional upper layer 7' a composition comprising an aqueous dispersion of elements of fluorine chemistry of the aqueous polymer dispersion type based on fluorinated latex (such as for example polyvinylidene fluoride, known as PVDF) and / or an aqueous dispersion based on latex resulting from the chemistry of the silicon element (for example a latex based on silicone or silane).

[0069] In advantageous examples of practical and non-limiting embodiments of the invention, the third functional upper layer 7', preferably of the liquid sealing type and / or with surface radiative properties, in particular with a high solar reflectance index, consists of a combustible organic material which requires the application, in liquid form, of one or more of the compositions above-mentioned in one or more stages, so as to obtain a single-layer material or a multi-layer material arranged in strata.

[0070] According to another particular characteristic of the complex and of the method according to the invention, the film thickness in the dry state of this functional upper layer 7' is > 0.05 mm and < 3 mm, preferably between 0.3 mm and 2 mm, more preferably still between 0.5 mm and 1.5 mm.

[0071] The term "film in the dry state" means the film obtained after complete evaporation of the solvent, or complete crosslinking of the resin, or complete coalescence of the latex, or complete reaction of the reactive species, allowing the physicochemical drying of the third functional upper layer 7', previously deposited in a liquid form on the second intermediate or base layer 5.

[0072] According to another possible particular characteristic of the invention, the third functional upper layer 7' may optionally comprise (integrate) a reinforcing veil. This additional reinforcing veil is embedded in the third functional upper layer 7'. This additional reinforcing veil is preferably combustible, so as not to prevent or significantly limit the expansion of the graphite of the intermediate layer 5 and therefore not to reduce the fire resistance performance of the multi-layer laminate complex 8. For example, this veil is composed of polyester. Thus, this additional reinforcing veil advantageously does not affect the fire resistance properties of the multi-layer laminate complex 8, and also does not impact the intumescence properties of the intumescent material 6 of the second intermediate layer 5.

[0073] In accordance with an embodiment variant already mentioned above, and compatible with most of the possible characteristics set out above, the functional upper layer 7', of the liquid or non-liquid waterproofing type, is light in color, even white, and has particular surface radiative properties. This layer 7' may in particular have a solar reflectance index (SRI) greater than 90, preferably greater than 100, typically after drying and before significant aging (property known under the designation "Cool Roof" in the building field). - cf. European Cool Roof Council). This SRI index is determined from the solar reflectivity and thermal emissivity of the surface considered (here layer 4) according to the ASTM E 1980-11 (2013) or EN 17190 (October 2018) standard. The multi-layer laminated complex (8) thus obtained, and therefore the roofing system that incorporates it, combines increased fire resistance performance with the fight against the effects of urban heat islands by reducing the surface temperature of the roofs.

[0074] Furthermore, it can be noted that the addition of the intumescent material 6, even of dark color, exclusively in the intermediate layer 5, makes it possible to guarantee the quality and uniformity of the light color or whiteness, and therefore the reflectivity performance, of the functional upper layer 7'.

[0075] Furthermore, the absence of granular intumescent material in this functional upper layer 7' does not affect the smoothness of its surface (absence of roughness - good resistance to fouling), whatever the nature of said layer.

[0076] According to a particular embodiment indicated by sample No. 10 of the multilayer laminate complex 8 in table 3 below, when the method for producing the multilayer laminate complex 8 provides that the latter comprises a silane-modified polymer as a third functional upper layer 7', a reinforcing veil, in particular of the polyester veil type, can be added.

[0077] Advantageously, the first lower layer 2 of membrane type consists of a bituminous membrane, preferably cold self-adhesive (ease of installation, without use of flame). Preferably, this first lower layer 2 of waterproofing membrane type is prefabricated in the factory. It can either be part of, and constitute the upper layer, of an existing roofing device, which the method according to the invention aims to functionalize in the context of subsequent rehabilitation or improvement work by covering with the second and third layers 5 and 7', or constitute the first lower layer 2 of a multi-layer laminated complex 8 in the context of the construction of a new roofing device. Furthermore, this membrane can also, if necessary constitute the top layer of a waterproofing system formed of two superimposed membranes, existing or newly installed.

[0078] In order to meet the regulatory criteria applicable in certain countries, and in particular in France, said multi-layer laminated complex 8 is configured, in particular the compositions and thicknesses of the first, second and third layers 2, 5 and 7' together forming a laminated complex 8 are determined, in particular with regard to the second intermediate base layer 5, in such a way that said laminated complex 8 has an external fire performance classification corresponding at least to BROOF t3 according to test method 3 of standard NF EN 1187 and in accordance with standard NF EN 13501-5. Examples of such compositions and thicknesses are indicated in particular in the tables which follow.

[0079] According to this standard, Test Method 3 evaluates the performance of the tested roofing system under attack from burning firebrands, wind and additional radiant heat, using as classification parameters the external fire propagation time (TE) and the time until fire penetration (Tp) into the roofing system. For a roofing system after implementation of Test Method 3, measured values ​​of TE 30 min and Tp > 30 min, gives an external fire performance classification corresponding to BROOF t3.

[0080] As illustrated by way of example in Figure 2, the present invention also relates to a functionalized roofing device 1, obtained by means of the method described above. This roofing device 1 comprises a bituminous waterproofing membrane or a similar waterproofing system 2, placed either directly on a roofing support or substrate 3, or on a functional layer 4 placed on this support or substrate 3, this waterproofing membrane or this similar waterproofing system 2 forming a first layer of a laminated complex 8.

[0081] According to an embodiment of the invention visible in Figure 2, between said roofing support or substrate 3 and said functional layer 4, said roofing device 1 may also optionally comprise, and in this order, a layer of bonding coating 10, for example a bonding coating (bituminous or not) associated or not with a layer of vapor barrier membrane 9.

[0082] According to one embodiment of the invention, the functional layer 4, possibly present, is a thermal insulation layer, preferably of the rigid type, and the first lower layer 2 of the membrane type serving as a base or lower layer of the multilayer complex 8 advantageously consists of a bituminous membrane, preferably cold self-adhesive.

[0083] According to the invention, the roofing device 1 is characterized in that the laminated complex 8 further comprises, on the one hand, present on at least part of the surface of said waterproofing membrane or said similar waterproofing system 2 forming a first layer, at least one base or bonding layer 5 comprising at least one intumescent material 6 as an additive, this base layer 5 forming a second intermediate layer of said laminated complex 8 and consisting of a bonding primer, and, on the other hand, a functional upper layer 7', or third layer, with a laminated or single-piece structure, resulting from the drying of at least one additional layer 7, possibly several successive additional layers 7, applied to said at least one base layer 5. This functional upper layer 7' does not have increased or particular fire resistance properties.The base or bonding layer 5 forming an intermediate layer between the aforementioned first and third layers 2 and 7', and it alone, comprises at least one intumescent material 6 as an additive and this base layer forming a bonding primer also has barrier functions to migrations between the first and third layers 2 and 7'.

[0084] Preferably, the multi-layer laminated complex 8 obtained by means of the method according to the invention corresponds to a complex having most of the characteristics indicated above and makes it possible to produce a functionalized roofing device 1 according to the present invention, as a new construction or renovated or rehabilitated existing construction.

[0085] In particular, the invention may advantageously provide that the first 2 and third 7' layers have mutually different physicochemical constitutions or are mainly based on materials having mutually different physicochemical constitutions, and that the fire resistance properties of the laminated complex 8, and advantageously those of the roofing device 1, are provided solely by the second intermediate or base layer 5, none of the first and third layers 2 and 7' having a physicochemical constitution giving it particular fire resistance properties.

[0086] In accordance with three possible embodiments of the invention, it may be provided: - that the functional upper layer 7' corresponds to a layer, in one piece or laminated, resulting from the drying of one or more additional layers 7 of the liquid sealing material type; - that the functional upper layer 7' corresponds to a layer, in one piece or laminated, preferably of a light color, possibly white, having surface radiative properties, and advantageously a solar reflectance index (SRI) greater than 90, preferably greater than 100, or, - that the functional upper layer 7', with a single-piece or laminated structure, consists of a continuous sealing layer of light or white color and has surface radiative properties, and advantageously a solar reflectance index greater than 90, preferably greater than 100.

[0087] When the functionalization of the roofing device 1 is intended, for example, for an advertising, aesthetic or more generally visual purpose, intended for third parties likely to see its surface, it may be provided that the second intermediate or base layer 5 and the functional upper layer 7' only partially cover the surface of the waterproofing membrane or similar waterproofing system 2 corresponding to the first layer and form a pattern of a decorative, representative or informative nature, preferably the functional upper layer 7' having a color different from that of the first layer (2).

[0088] The following tests, carried out by the inventors, on different samples (examples 1 to 11, listed in tables 1 to 3 below) show the advantageous properties, in terms of fire resistance, of a multi-layer laminate complex (8) having the characteristics of the invention.

[0089] Sample compositions: Tables 1 to 3 below summarize the compositions of the layers, on the one hand, of multilayer complexes 8 according to the invention (examples 1, 4, 7, 9, 10 and 11 above) and, on the other hand, of similar multilayer complexes but with a traditional base layer (examples 2, 3, 5, 6 and 8 above), that is to say devoid of intumescent material in the intermediate layer 5. Table 1 Table 2 Table 3

[0090] In the examples in tables 1 to 3 above: for the lower layer 2: - the “self-adhesive bituminous membrane” corresponds to the membrane marketed by the company SOPREMA under the reference SOPRASTICK SARKING SABLE; - the existing self-protected bituminous complex corresponds to a self-protected bituminous waterproofing complex, for example marketed by the company SOPREMA under the SOPRAFIX HP complex associated with SOPRAFIX AR; - the “welded bituminous membrane” corresponds to the membrane marketed by the company SOPREMA under the reference SOPRALENE FLAM 180; * for intermediate layer 5: - “Alsan 140” corresponds to a 2K PU (polyurethane) resin primer layer applied with a consumption of 500 g / m 2 , marketed by the company SOPREMA; - “Alsan 172 CR” corresponds to a primary layer of poly-(methyl methacrylate) called PMMA applied with a consumption of 700 g / m 2 , marketed by the company SOPREMA; - "Texprime A+B" corresponds to a primary layer of aqueous epoxy dispersion 2 applied with a consumption of 300 g / m 2 , marketed by the company SOPREMA; - “Alsan EP 120” corresponds to a 2K epoxy resin primer layer applied with a consumption of 500 g / m 2 , marketed by the company SOPREMA; - “Alsan H80” corresponds to a 1 K PU (polyurethane) resin primer layer applied with a consumption of 500 g / m 2 ; - the “expandable graphite” added to the second intermediate layer (5) corresponds to the expandable graphite marketed by the company LUH under the reference GHL PX 98 HE. It is expressed as a mass percentage added to the intermediate layer (5) relative to the total mass of said intermediate layer (5), as well as by the “graphite dosage” parameter which corresponds to the surface quantity expressed in g / m 2 of expandable graphite present between the lower (or first layer 2) and upper (or third layer 7') layers, therefore in the intermediate layer (or second layer 5) and only it; - the intermediate layer 5 is applied on the first lower layer 2 of the sample of the complex taken into account according to a consumption expressed in kg / m 2 ; for the functional upper layer 7': - “Alsan 600” corresponds to a top layer of 1 K PU resin type applied with a consumption of 1 kg / m 2 , this resin being marketed by the company SOPREMA; - “Alsan 902 CR” corresponds to a top layer of 1 K PU resin type applied with a consumption of 1 kg / m 2 , this resin being marketed by the company SOPREMA; - “Alsan 970 CR” corresponds to a top layer of PMMA resin type applied with a consumption of 600 g / m 2 , this resin being marketed by the company SOPREMA; - “Alsan Flashing Neo” corresponds to a top layer of silane-modified polymer resin applied with a consumption of 3.2 kg / m 2, in two layers with a reinforcing veil embedded between the two layers, this resin being marketed by the company SOPREMA; - “Alsan 320” corresponds to a top layer of acrylic aqueous dispersion type applied with a consumption of 1.6 kg / m 2 , in two layers with a reinforcing veil embedded between the two layers, this product being marketed by the company SOPREMA; - “Fleece 110P” means a polyester reinforcement fleece impregnated and integrated into the upper 7' layer and having a surface mass of 110 g / m2, fleece which is marketed by the company SOPREMA; - “50% ATH” means the aluminum trihydrate supplemented in the functional upper layer 7' as a flame retardant, in a content representing 50% by mass relative to the total mass of the functional upper layer 7'; - “4% Disflamoll® DPK” means diphenyl cresyl phosphate, marketed by Lanxess, incorporated into the functional top layer 7' as a flame retardant at a content representing 4% by mass relative to the total mass of the functional top layer 7'. - the products “Alsan 902 CR” and “Alsan 970CR” of examples Nos. 4, 5, 9 and 11 make it possible to obtain a 7' functional layer with an SRI index greater than 90 (so-called “CooIRoof” effect). - the products “Alsan 600” and “Alsan Flashing Neo” of examples 1 and 10 provide 7' functional layers of the liquid waterproofing type. - the product “Alsan 320” (RAL 9010) provides a waterproof 7' functional layer with an SRI index greater than 90.

[0091] Tables 1 to 3 also mention for each functional top layer 7', the total thickness of the layer in mm.

[0092] The designations “Alsan”, “Texprime”, “Alsan Flashent”, “SOPRASTICK”, “SOPRALENE” and “SOPRAFIX” are registered names of the company SOPREMA.

[0093] On each of these 11 samples, external fire resistance tests in accordance with test method 3 of XP CEN / TS 1187 and standard NF EN 13501-5 were carried out under the following conditions: * the tests were carried out with a slope of 5° (degree of angle) in order to validate the results for multi-layer laminated complexes 8 intended for roofs installed with slopes less than or equal to 10° degree of angle, * the test support consists of a steel support covered with “ROCKACIER® B” rock wool from the Rockwool company, * the test support is covered with a complex consisting of the layers according to the sample numbers described in the above-mentioned tables 1 to 3.

[0094] Table 4 below summarizes the significant results in the context of the invention of these different tests: Table 4

[0095] For sample No. 2 of complex, identical to sample No. 1 but without graphite in the intermediate layer 5, the BROOF class t3 is not achieved. For sample No. 3, identical to sample No. 2 with the addition of a flame retardant agent of the “Disflamoll® DPK” type in the functional upper layer 7', the BROOF class t3 is not achieved. Thus, these results show that only a multilayer laminated complex (8) according to the invention, for example such as sample No. 1, having in its only intermediate layer 5, an intumescent material 6, in particular of the graphite type, makes it possible to achieve the BROOF class t3 with test method 3 of XP CEN / TS 1187 applicable according to standard NF EN 13501-5.

[0096] The results obtained for samples No. 4 to 6 also reveal that a modification of the nature and type of the intermediate layer 5 and the functional upper layer 7' does not impact the fact that the presence of the intumescent material 6, of graphite type in the intermediate layer 5, makes it possible to achieve the BROOF t3 class. In addition, as shown by the result obtained for sample No. 6, the addition of an additional veil and an ATH flame retardant agent in the functional upper layer 7', to the composition of sample No. 4, does not make it possible to achieve the BROOF t3 class. not to reach the BROOF t3 class in the absence of graphite in the intermediate layer 5. Neither the veil nor the additional flame retardant has any impact on the complex to reach the BROOF t3 class.

[0097] The results obtained for samples No. 7 to 11 show that a modification of the nature and type of the intermediate layer 5 and / or the functional upper layer 7', with or without additional veil and / or flame retardant agent, does not impact the samples of the multilayer laminate complex 8 tested and the possibilities of reaching the BROOF t3 class. Only the presence of expandable graphite in the intermediate layer 5 makes it possible to reach, in particular for samples No. 7 and 9 to 10, the BROOF t3 class.

[0098] Consequently, these tests illustrate that the multi-layer laminated complex 8 of the present invention meeting class BROOF t3 of test method 3 of standard NF EN 13501-5 is particularly advantageous for increasing resistance to fire and its propagation, in particular in the context of use in a functionalized roofing device 1 of a home or a building.

[0099] As illustrated non-limitingly by the different examples of Tables 1 to 3, and according to an advantageous characteristic of the invention, the materials or compositions of the materials constituting respectively the second intermediate layer or base layer 5, on the one hand, and the functional upper layer or third layer 7', on the other hand, are different from each other (each example of the tables shows a pair of different materials for layers 5 and 7). Although different, and therefore able to be selected according to specific or reinforced properties, sought for each of these two layers (adhesion; barrier; functionalization), the materials of the two layers are of course compatible with each other, in particular in terms of mutual adhesion.

[0100] In accordance with a first embodiment of the invention, the materials or compositions constituting respectively the second intermediate layer or base layer 5, on the one hand, and the functional upper layer or third layer (7'), on the other hand, are of different physicochemical natures (examples 7, 8 and 10).

[0101] In accordance with a second embodiment of the invention, the materials or compositions constituting respectively the second intermediate layer or base layer 5, on the one hand, and the functional upper layer or third layer 7', on the other hand, are of the same physicochemical nature, but of different types (examples 1, 4, 9 and 11). By different types, for materials of the same physicochemical nature, is understood in the present in particular different formulations (but with similar compounds), different presentations, etc. (1 K vs 2K, Alsan 172 vs Alsan 970, ... .).

[0102] Of course, the invention is not limited to the embodiments described and shown in the attached drawings. Modifications remain possible, particularly from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims

Claims

1. Method for functionalizing a roofing device (1), with at least maintaining and preferably increasing its fire resistance, said roofing device (1) comprising, at least, a bituminous waterproofing membrane or a similar waterproofing system (2), previously laid or having just been laid either directly on a roofing support or substrate (3), or on a functional layer (4) laid on this support or substrate (3), this waterproofing membrane or this similar waterproofing system (2) forming a first layer, method characterized in that it comprises the steps consisting of: -applying, on at least part of the surface of said waterproofing membrane or said similar waterproofing system (2), at least one base or bonding layer (5) which comprises at least one intumescent material (6) as an additive, this base layer (5) forming a second intermediate layer and consisting of a bonding primer; - then applying at least one additional layer (7) on said at least one base layer (5), this or these additional layer(s) (7) constituting after drying a functional upper layer (7'), or third layer, and preferably not having increased or particular fire resistance properties, the first, second and third layers (2, 5, 7') thus forming a multi-layer laminated complex (8) and the base layer (5) forming an intermediate layer between the aforementioned first and third layers (2 and 7'), and it alone, comprising at least one intumescent material (6) as an additive and also having barrier functions to migrations between the first and third layers (2 and 7').

2. Method according to claim 1, characterized in that the or each additional layer (7) applied is of the liquid sealing material type, the resulting functional upper layer (7') having, after drying, a continuous surface and a single-piece or laminated thickness structure.

3. A method according to claim 1, characterized in that the or each additional layer (7) applied consists of a liquid coating material and the resulting functional top layer (7') exhibits surface radiative properties, particularly in the wavelengths of sunlight and advantageously exhibiting a continuous surface and a single-piece or layered thickness structure.

4. Method according to claim 3, characterized in that the or each additional layer (7) applied consists of a light-colored, for example white, liquid coating material, the resulting functional top layer (7'), which exhibits a single-piece or laminated structure, having a solar reflectance index (SRI) greater than 90, preferably greater than 100.

5. Method according to claim 2 or 3, characterized in that the functional upper layer (7'), with a single-piece or laminated structure, is a light-colored, or even white, sealing layer and has a solar reflectance index greater than 90, preferably greater than 100.

6. Method according to any one of claims 1 to 5, characterized in that the sealing membrane or similar sealing system (2), on the one hand, and the functional upper layer (7'), on the other hand, have mutually different physicochemical constitutions or are mainly based on materials having mutually different physicochemical constitutions.

7. Method according to any one of claims 1 to 6, characterized in that the waterproofing membrane or similar waterproofing system (2) and the functional upper layer (7'), as well as where appropriate the functional layer (4) possibly present, have a physicochemical constitution or a composition which does not give them increased or particular fire resistance properties.

8. Method according to any one of claims 1 to 7, characterized in that the intumescent material (6) present in the base layer (5) consists of exfoliating graphite or expandable graphite, preferably present in the form of grains or particles, incorporated in the base material predominantly forming this layer.

9. Method according to any one of claims 1 to 8, characterized in that the intumescent material (6) constitutes between 5% and 50%, more preferably between 5% and 40%, preferably between approximately 10% and 30%, more preferably between 10% and 20%, by weight of the material forming the second intermediate or base layer (5), and is in particulate form with an average particle size advantageously between 75 pm and 500 pm, preferably between 100 pm and 300 pm.

10. Method according to any one of claims 1 to 9, characterized in that the intumescent material (6) is present in the base layer (5) with a surface mass of between 10g / m 2 and 500g / m 2 , more preferably between 20g / m 2 and 250g / m 2 , and even more preferably between 30g / m 2 and 150g / m 2 and is in particulate form with an average particle size advantageously between 75 pm and 500 pm, preferably between 100 pm and 300 pm. [Claim 1 1] Method according to any one of claims 1 to 10, characterized in that the base material forming the second intermediate or base layer (5) is chosen from 1K or 2K polyurethanes, PMMA (Poly Methyl Methacrylate) based resins, epoxy resins, silane modified polymers and aqueous dispersions of acrylic, or methacrylic, or urethane, or epoxy polymers or copolymers of these compounds.

12. Method according to any one of claims 1 to 11, characterized in that the functional upper layer (7') is of organic nature and results from the application of at least one layer (7) comprising a material formed from a composition chosen from compositions based on 1K or 2K polyurethane resins, resins based on PMMA (Poly Methyl Methacrylate), epoxy resins, silane-modified polymers, fluorinated or silicone polymers, or aqueous dispersions of acrylic, or methacrylic, or urethane, or epoxy polymers or copolymers of these compounds, this layer (7') possibly comprising or integrating a reinforcing veil.

13. Method according to any one of claims 1 to 12, characterized in that the materials or compositions constituting respectively the second intermediate layer or base layer (5), of a part, and the functional upper layer or third layer (7'), on the other hand, are different from each other.

14. Method according to claim 13, characterized in that the materials or compositions constituting respectively the second intermediate layer or base layer (5), on the one hand, and the functional upper layer or third layer (7'), on the other hand, are of different physicochemical natures.

15. Method according to claim 13, characterized in that the materials or compositions constituting respectively the second intermediate layer or base layer (5), on the one hand, and the functional upper layer or third layer (7'), on the other hand, are of the same physicochemical nature, but of different types.

16. Method according to any one of claims 1 to 16, characterized in that the film thickness in the dry state of the functional upper layer (7') is > 0.05 mm and < 3 mm, preferably between 0.3 mm and 2 mm, more preferably still between 0.5 mm and 1.5 mm.

17. Method according to any one of claims 1 to 16, characterized in that the first layer (2) consists of a cold self-adhesive bituminous membrane.

18. Method according to any one of claims 1 to 17, characterized in that the compositions and thicknesses of the first, second and third layers (2, 5 and 7') together forming a laminated complex (8) are determined, in particular with regard to the second intermediate or base layer (5), in such a way that said laminated complex (8) has an external fire performance classification corresponding at least to BROOF t3 according to test method 3 of standard NF EN 1187 and in accordance with standard NF EN 13501 -5 of 2016.

19. Functionalized roofing device (1), obtained by means of the method according to any one of claims 1 to 18, said roofing device (1) comprising a bituminous waterproofing membrane or a similar waterproofing system (2), laid either directly on a roofing support or substrate (3), or on a functional layer (4) laid on this support or substrate (3), this waterproofing membrane or system of similar waterproofing (2) forming a first layer of a laminated complex (8), roofing device (1) characterized in that the laminated complex (8) further comprises, on the one hand, present on at least part of the surface of said waterproofing membrane or said similar waterproofing system (2) forming a first layer, at least one base or bonding layer (5) comprising at least one intumescent material (6) as additive, this base layer (5) forming a second intermediate layer of said laminated complex (8) and consisting of a bonding primer, and, on the other hand, a functional upper layer (7'), or third layer, with a laminated or single-piece structure, resulting from the drying of at least one additional layer (7), possibly of several successive additional layers (7), applied to said at least one base layer (5),this functional upper layer (7') not having increased or particular fire resistance properties and the base layer (5) forming a second intermediate layer between the aforementioned first and third layers (2 and 7'), and it alone, comprising at least one intumescent material (5) as an additive and further having barrier functions to migrations between the first and third layers (2 and 7').,

20. Roofing device (1) according to claim 19, characterized in that the first (2) and third (7') layers have mutually different physicochemical constitutions or are mainly based on materials having mutually different physicochemical constitutions, and in that the fire resistance properties of the laminated complex (8), and advantageously those of the roofing device (1), are conferred solely by the second intermediate or base layer (5), neither of the first and third layers (2 and 7') having a physicochemical constitution conferring particular fire resistance properties on it.

21. Roofing device (1) according to claim 19 or 20, characterized in that the functional upper layer (7') corresponds to a layer, in one piece or laminated, resulting from the drying of one or more additional layers (7) of liquid sealing material type.

22. Roofing device (1) according to claim 19 or 20, characterized in that the functional upper layer (7') corresponds to a layer, in one piece or laminated, preferably of a light color, possibly white, having radiative properties, and advantageously a solar reflectance index (SRI) greater than 90, preferably greater than 100.

23. Roofing device (1) according to any one of claims 19 to 22, characterized in that the functional upper layer (7'), with a single-piece or laminated structure, is a continuous waterproofing layer of light or white color and has radiative properties, and advantageously a solar reflectance index greater than 90, preferably greater than 100.

24. Roofing device (1) according to any one of claims 19 to 23, characterized in that the second intermediate or base layer (5) and the functional upper layer (7') only partially cover the surface of the waterproofing membrane or similar waterproofing system (2) corresponding to the first layer and form a pattern of a decorative, representative or informative nature, preferably the functional upper layer (7') having a different color from that of the first layer (2).

25. Roofing device (1) according to any one of claims 19 to 24, characterized in that the functional layer (4) possibly present is a thermal insulation layer, preferably of the rigid type, the first layer (2) of the membrane type advantageously consisting of a bituminous membrane, preferably cold self-adhesive.

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