ES2361117T3 - RADIANT BARRIER ASSEMBLY OF VENTILATED CAVITY AND PROCEDURE. - Google Patents

Abstract

Radiant ventilated cavity barrier assembly (2, 2A-K), which can be mounted on a surface of a building (4), comprising: a barrier (12) configured as a panel that has an interior and exterior surface (18; 22); a support assembly (14, 14E, 14F, 14H) attached to the barrier (12) and extending inwards with respect to the inner surface (18), the support assembly having a separate part of the inner surface (18) ) and which can be attached to a surface of the building to form a ventilated cavity (24, 24E-24H) that is created between the surface of the building (4) and the inner surface (18) and induce a flow of air through the cavity (24, 24E-H); and a low-emissivity element (20, 20A, 20B) located on the inner surface (18), and / or suspended within the ventilated cavity to be formed between segmented supports (16) of the support assembly (14, 14E, 14F, 14H).

Description

BACKGROUND OF THE INVENTION

This invention relates generally to roof / exterior cladding assemblies of buildings and, in particular, to the inclusion of ventilated radiant barrier systems within said assemblies, configured to provide: thermal regulation to the radiation and convection of the outer part of the building, displacement of conventional ballast materials, prolongation of the life of the building structure material, and support structure for photovoltaic modules.

The thermal insulation of buildings, to help keep the interior of buildings cold in summer and hot in winter, has always been an important design criterion in all climates except in the mildest ones. Conventional thermal insulation mainly involves insulating walls and ceilings to minimize heat transfer by conduction. However, thermal transfer by convection and radiation to and from building surfaces can also be important.

From the Japanese patent application JP07292908 a roof with a power generation function is known. US patent US5128181 describes a building element. The English fragment of JP07055189 describes an energy saving curtain wall mounted with a solar cell.

SUMMARY DESCRIPTION OF THE INVENTION

The present invention is directed to a ventilated cavity radiant barrier assembly that finds particular utility using a photovoltaic (PV) module as a barrier, which reduces the heating and cooling requirements of a building by reducing heat transfer to the building during cooling periods. and reducing heat losses from the building during heating periods. The radiant barrier assembly can also help insulate the building surface from the effects of wind, rain, and other inclement weather. The invention is adaptable for use in the construction of surfaces that are vertical, horizontal or inclined.

The ventilated cavity radiant barrier assembly includes a barrier, typically a PV module, which has an inner and outer surface. A support assembly is attached to the barrier and extends inwardly from the interior surface of the barrier to a building surface creating a ventilated cavity between the surface of the building and the interior surface of the barrier. A low emissivity element (low-e) is associated with the inner surface; that is, one or more low-e surfaces are placed on the surface of the building and the interior surface of the barrier or between them.

The support assembly is typically attached to the surface of the building so that no penetrations are formed on the surface of the building. This can be achieved, for example, by the use of adhesives, Velcro-type fasteners or by embedding the base of the support assembly within an insulating layer covering the roof surface. It can also be achieved by designing the assembly to minimize wind lift, laterally coupling adjacent assemblies into an integrated array of assemblies, by using ballast type elements and by other modes. In some situations, such as when each assembly is in the form of a splint, fasteners that penetrate the surface of the building can be used.

The low emissivity element is typically disposed on the inner surface of the barrier. By doing this, manufacturing difficulties are minimized, installation is simplified, wear is reduced by inclement weather of the low-e surface and control is increased since the entire assembly can be carried out at the factory.

Placing the low-e element on the roof surface eliminates the potential temperature increase of the PV module. However, this placement also subjects the low-e surface to greater environmental degradation, such as oxidation and other chemical attacks of dust, dirt and other airborne contaminants, as well as dimming by dust and dirt that also reduce the effectiveness of the low-e surface. Also, since the low-e element must typically be applied to the building surface in the field, there is a reduction in quality control compared to having the low-e element applied at the factory.

The use of the low-e element suspended within the ventilated cavity between the inner surface of the barrier and the building surface, provides the best thermal performance of any single position for the low-e element, apparently because a double is created ventilated cavity However, it is the most complex and expensive to manufacture and install. This increase in complexity and cost can often be offset by the advantages resulting from its better thermal efficiency.

The use of a low-e element in more than one position, typically on the inner surface of the barrier and on the surface of the building, can often improve thermal efficiency. This higher thermal efficiency may be useful or necessary in certain applications. However, it is expected that for many applications the use of low-e elements in positions other than the inner barrier surface will not be cost effective.

In certain situations the barrier is not a PV module but rather is a thermal insulator. In such cases the outer surface of the barrier is preferably a surface of high reflectivity and high emissivity. This, together with the low emissivity surface associated with the inner surface of the barrier and typically therein, provides a better thermal efficiency of the system.

The assembly is preferably made so that convective air flow through the ventilated cavity is improved by creating the cavity with at least part of the cavity outlet higher than the cavity inlet. This is typically achieved automatically when assemblies are mounted on a vertical surface of a building, such as a wall, or an inclined surface of a building, such as a sloping roof. When the surface of the building is essentially horizontal, the barrier can be mounted to the substantially horizontal surface of the building at an angle to the horizontal to favor the flow of air through the ventilated cavity. In addition, or alternatively, the air may be forced through the ventilated cavity through the use of, for example, a vent. Although a fan could also be used, it is preferred that the system be passive to help reduce energy costs, decrease installation costs, and reduce system complexity. Wind deflectors adjacent to the cavity entrance can be used to help deflect the wind into the cavity; This can be particularly useful if there is prevailing wind from a certain direction. The use of vents, fans or wind deflectors can be important when it is necessary or desirable to mount the barrier parallel to a substantially horizontal building surface.

Another aspect of the invention is a process by which a radiant barrier assembly can be performed. A barrier that has an inner and outer surface is selected; A low emissivity element is typically applied to the inner surface of the barrier. A support assembly is mounted to the barrier so that a part of the support assembly extends outwardly away from the inner surface of the barrier. This assembly can thus be mounted to the surface of the building in a simple and effective way.

The invention is also directed to a method for mounting a ventilated radiant barrier assembly to a building surface. The barrier is attached to the building surface using the support assembly to create a ventilated cavity between an interior surface of the barrier and the building surface. During the clamping stage, at least one low-e element is placed on the interior surface and the surface of the building or between them. This stage is often performed with the low-e element adhered to the inner surface of the barrier. The low-e element can also, for example, be sprayed on the surface of the building or suspended as a film in the ventilated area between the surface of the building and the inner surface of the barrier.

It has been found that a roof having a black roof surface has a solar absorption of approximately 0.85 while a white roof surface has a solar absorption of approximately 0.60. The solar absorption can be reduced to approximately 0.50 by covering the roof surface with a conventional insulating paver made of 5 cm thick polystyrene covered with approximately 16 mm concrete.

By suspending a horizontally placed radiant barrier (which could be, for example, a PV module or an environmentally resistant rigid panel) approximately 1.2 to 10 cm on a horizontal flat roof surface, the solar absorption coefficient is reduced to approximately 0.35. The solar absorption coefficient is reduced to approximately 0.30 by adding a low-e element along the inner surface of the barrier; placing the barrier at an angle to the horizontal, preferably at least about 5 °, causes the cavity inlet to be lower than the cavity outlet, a natural ventilation air path is created and the solar absorption is reduce to about 0.

The invention not only provides significant improvements in thermal performance, but also, when the barrier is a PV module, it provides a source of non-polluting electricity from the solar radiation that is projected onto the PV module.

From the following description of the invention, in which preferred embodiments have been described in detail in combination with the accompanying drawings, other features and advantages will be appreciated.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a simplified side view of radiant ventilated cavity barrier assemblies made in accordance with the invention, mounted on a sloping roof and a vertical side wall of a building;

Figure 1A is a side elevation view of the ceiling mounted radiant barrier assemblies of Figure 1 illustrating the passage of air through the ventilated cavities;

Figure 2 is an enlarged simplified side view of one of the barrier assemblies that include a low-e element along the inner surface of the barrier;

Figure 2A is a simplified side view of a barrier assembly similar to Figure 2 but including a low-e element on the surface of the building and in an intermediate position between the interior surface of the barrier and the surface of the building;

Figure 3 illustrates an alternative embodiment of the invention of Figure 2 in which the same support element supports adjacent barriers and low-e elements are arranged on the interior surface and on the surface of the building;

Figure 4 shows an alternative embodiment of the invention of Figure 3 in which the support assembly includes mutual coupling legs along the side edges of the barriers;

Figure 4A shows a modified version of the embodiment of Figure 4 in which the mutually engaging legs are secured to the building surface using a substantially U-shaped fastener or connector;

Figures 5 and 5A are simplified top and side plan views of another alternative embodiment of the invention in which the barrier is on a slope and is supported at its lower and upper end by means of angular separators on a panel of thermal insulation that has projections and cavities of mutual coupling that help eliminate the need to adhere or otherwise fasten the barrier assembly to the surface of the building;

Figure 6 illustrates yet another embodiment of the invention in which the lower ends of the supports of the support assembly are embedded within a continuous layer of thermal insulation thus securing the radiant barrier assembly to the building surface;

Figure 7 illustrates another alternative embodiment of the invention in which the radiating barrier assembly is in the form of a splint;

Figure 8 shows a slightly modified version of the embodiment of Figure 7 mounted on a sloping roof so that the passage of air with each of the radiant barrier assemblies is collected in a hot air manifold;

Figure 9 illustrates another embodiment of the invention in which the support assembly includes a fluid permeable substrate that partially or totally fills the ventilated cavity and supports the barrier but allows air to pass through the fluid permeable substrate in order to ventilate The cavity;

Figure 10 is a simplified cross-sectional side view illustrating the invention used with a corrugated or crimped roof system in which vertical undulations or right joints can provide support for the barrier and create a ventilated cavity between the interior surface of the barrier and the surface of the building, which in this case is defined by the channels of the crimped roof system; Y

Figure 10A illustrates an alternative embodiment of the invention of Figure 10 in which the radiating barriers are secured using independent support elements between the undulations or projecting joints of the roof system.

DESCRIPTION OF PREFERRED EMBODIMENTS

Figures 1 and 2 illustrate a series of radiant ventilated cavity barrier assemblies 2 mounted on different surfaces of a building 4, in particular a roof 6 and a wall 8 of a building 10. Assembly 2, as shown in the Figure 2, includes a barrier 12, typically a PV module or a rigid panel, which is resistant to the weather and is mounted on the surface of the building 4 by a support assembly 14. If the barrier 12 is a PV module, such as one marketed by Solarex of Frederick, Maryland as MSX 120, different electrical wires and cables will be used; they are not shown in the drawings for reasons of clarity in the illustration. If the barrier 12 includes a thermal insulation component, it preferably has an insulation value of at least about R2 and preferably from about R5 to R15. Suitable materials for the insulation component include polystyrene, polyurethane and isocyanurate.

If a PV module includes a PV panel supported by an insulating layer, the thermal insulating valve of the barrier typically ranges between R5 and more than R20 approximately depending on the type of insulating material used and its thickness.

In the simplified embodiment of Figures 1, 1A and 2, the support assembly 14 includes four supports 16 attached to the inner surface 18 of the barrier 12 and extending downwards away from it. The supports 16 are also attached to the surface of the building 4, typically without penetrating the surface of the building 4 as will be described in greater detail below.

The assembly 2 also includes a low emissivity element 20 on the inner surface 18. The low-e elements are shown by dashed lines in the figures for ease of illustration. The low-e element 20 is preferably integral with the barrier 12 on the inner surface 18 and can have a variety of shapes. The low-e element 20 can include a metallic or metallized plastic sheet such as Mylar®, low-e spray coatings and can be applied to the barrier 12 by rolling or painting or spraying. Emissivity is defined as the ratio of the total radiation energy of a real surface to that of a black body surface. A low-e means that it has an emissivity typically below 0.4, and preferably below 0.08. Low emissivity, in general, is a characteristic of shiny metal surfaces. The barrier 12 also includes an outer surface 22. The outer surface 22 may be the solar receiving surface when the barrier 12 is a PV module. When the barrier 12 is a rigid panel, the outer surface 22 may be a surface of high reflectivity and high emissivity, such as a white painted surface, for better thermal conditioning of the building 10.

The assembly 2 defines a ventilated cavity 24 between the surface 4 of the building and the inner surface 18 of the barrier 12. The arrangement of the ventilated cavity 24 allows a free air flow, and thus the flow of cold air currents according to It is indicated by arrows 26, between the barrier 12 and the surface 4 of the building. The ventilated cavity 24 is preferably about 1.2 cm to 10 cm (1/2 to 4 inches) tall and preferably about 4.8 cm (1.9 inches) tall. In the embodiments of Figure 1, 1A and 2, the ventilated cavity 24 has a substantially uniform height between an inlet of the cavity 28 and an outlet of the cavity 30. In the embodiment of Figures 1 and 1A, the outlet of the cavity 30 is higher than the entrance of cavity 28 to help cause the cooling air to pass through the ventilated cavity 24. This is achieved naturally when assemblies 2 are mounted relative to vertical walls 8 or sloping ceilings 6 as in Fig. 1. The favoring of the air passing through the ventilated cavity 24 when radiant barrier assemblies 2 are used in a substantially horizontal ceiling (which includes a moderately inclined ceiling up to an inclination of approximately 2:12) is achieved by the use of an inclined barrier as described with reference to figures 5 and 6.

Figure 2A illustrates an alternative embodiment of the invention with the same elements designated with the same reference numbers. The radiant barrier assembly 2A is shown including a barrier 12 supported on the surface 4 of the building by means of segmented supports 16A. Low-e elements 20, 20A and 20B are used on the inner surface 18 of the barrier 12 and the surface 4 of the building and between them. In particular, a low-e element 20A is suspended within the ventilated cavity 24 between the segmented supports 16A in effect to produce two ventilated cavities. An example of a low-e 20A element is a galvanized steel sheet, approximately 24 gauge. The low-e element 20A may include a low-e surface in front of each surface 18, 4 or both. The low-e element 20B is typically made by spraying or painting with metallic paint on top of the surface 4 of the building before the installation of the assembly 2A. A suitable material for the low-e 20B element is that sold by Solar Corporation of Princeton, New Jersey as LO / MIT-I. As described above in the summary description, there are advantages and disadvantages related to the use of low-e elements on the inner surface 18, on the surface 4 of the building and between the two surfaces. Based on the particular circumstances, one, two or all three low-e elements 20, 20A and 20B can be used with a radiated barrier assembly of ventilated cavity.

Fig. 3 illustrates a radiant ventilated cavity barrier assembly 2B in which the supports 16B are in the form of supports in I that support the edges of adjacent barriers 12 on the surface 4 of the building. The surface 4 of the building is shown including a substrate of the surface of the building 32 in which a weatherproof membrane 34 is used. In this embodiment, the low-e element 20B is used in the membrane 34, and a low-e element 20 is used on a lower surface 18. The supports 16B are secured to the inner surface 18 by using elements of fastener 36 while the lower part of the supports 16B is secured to the membrane 34 of the building surface 4 by the use of an appropriate adhesive 38. Velcro type fasteners or other suitable fasteners could also be used to hold the supports 16B to barrier 12 and surface 4.

Figure 4 shows another embodiment of the invention in which the assembly 2C is shown with a different type of support assembly 14C. The support assembly 14C includes a channel or body 40, a support barrier 12, and mutual locking legs 42, 44 along the side edges of the body 40. The body 40 essentially forms the inner surface 18 of the barrier 12 with the low-e element 20 on the inner surface 18. The low-e element 20B is applied to the surface 4 of the building as with the embodiment of figure 3. The legs 44 are attached to the surface 4 using fasteners such as adhesives, Velcro fasteners, other fasteners, etc. The legs 42 are attached to the legs 44 both by their mutual mechanical coupling illustrated in Figure 4, and by, if appropriate, the use of an adhesive or sealant between the areas of mutual coupling of the legs. Note that the spacing spaces between the legs 42, 44 have been exaggerated in Figure 4 for illustrative purposes.

Figure 4A illustrates an alternative to the radiant barrier assembly 2C of Figure 4. The 2D assembly uses a clamping element or connector 46 to couple the legs 42, 44 and secure the legs to the surface 4. This allows the connector 46 to be mounted to the surface 4 before the placement of the barrier 12, with the channel 40 and the legs 42, 44 extending therefrom, on the surface 4 of the building.

An alternative embodiment of the invention is shown in Figures 5 and 5A, in which the assembly 2E has been designed for use in flat roofs (substantially horizontal). The support assembly 14E includes a pair of angular separators 16E that support the barrier 12 on a slope of at least about 5 °, and preferably about 10 ° to 20 ° with respect to the horizontal. The spacers 16E are held by a thermal insulation panel 48. The panel 48 has a shoulder 52 that extends into a cavity 54 formed in an adjacent panel 48 to allow mutual engagement of adjacent assemblies 2E. The ventilated cavity 24E is open to the atmosphere through the entrance of the cavity 28E, formed at the lower end of the barrier 12, and through an outlet of the cavity 30E. The outlet of the cavity 30E is formed as a space between the upper end of the barrier 12 and a baffle panel 50, the panel 50 being also supported by the spacers 16E. In this way, the barrier 12 is inclined for better reception of solar radiation at appropriate latitudes and climates and is inclined to cause the cavity inlet to be lower than the cavity outlet for better air flow and this way to cool the ventilated cavity 24E.

Figure 6 illustrates another embodiment of the invention in which the assembly 2F presents some of the attributes of the embodiments of Figures 4 and 5. As can be seen, the support assembly 14F includes a support barrier 12 of the channel 40F forming An angle to the horizontal. Channel 40F includes a reverse angle zone 56 that is perforated for air ventilation. The air can enter the ventilated cavity 24F through an inlet 28F of the cavity, formed by the holes formed in the adjacent channel 40F to the lower end of the barrier 12; air flows up through the cavity 24F and through the outlet 30F of the cavity formed adjacent the upper end of the barrier 12 through the holes in the reverse angle zone 56. The support assembly 14F includes fasteners 62 having a base 64 that is arranged adjacent to a membrane or lining 34, the lining 34 covering a continuous insulating layer 68. The support element 62 also includes a vertical extension zone 66 extending upwardly away from the base 64 The support assembly 14F also includes spacers or legs 58 that extend down the channel 40F; legs 58 have bases 60 that rest on base 64.

The extension 66 extends upwards between the legs 58 and ends in fasteners or wings that can be curved 70 at the outer ends of the zone 66. The combination of the barrier 12 supported by the channel 40F with legs 58 extending from the lateral edges of the channel, it can be held in position between pairs of support elements 62. During this final installation stage, fasteners or wings 70 rotate downwards and then are retained again in the orientation of Figure 6 to engage and hold in position the side edges of channel 40F.

In the embodiment of Figure 2F, the support elements 62 are indirectly attached to the substrate 32 of the building surface using an adhesive to hold the bases 64 to the lining 34. It may be desirable to make the extension 66 longer and make the base 64 is directly attached to the substrate 32 of the building surface, preferably with elements that do not penetrate the surface such as adhesive, or fasteners that penetrate the surface such as ceiling nails, in appropriate positions. The continuous insulating layer 68 is then applied, typically by spraying foam, such as polyurethane, onto the substrate 32 of the building surface. The weather resistant membrane 34 is then applied to the continuous insulating layer 68 to provide the desired impermeability for the building.

The insulating layer 68 and the insulation panel 48 each preferably have an insulation value of at least about R3 per inch (R1.2 per cm). Layer 68 and panel 48 are typically about 2.5 to 7.5 cm (1 to 3 inches) thick.

Figure 7 illustrates a 2G radiant barrier assembly made in the form of a splint. The radiant barrier assembly 2G includes a barrier 12 attached to a base 72 by two or more parallel edge separators 74. As shown by arrows 26, the air flow between barrier 12 and base 72 provides cooling to the 24G ventilated cavity. The base 72 has a larger surface area than the panel 12, preferably at least about 20% larger, to allow mounting the 2G assemblies as slats.

Figure 8 illustrates a second embodiment of the invention of the splint type in which the radiating barrier assemblies 2H mounted to be in contact with each other but with the lower ends of the ventilated cavities 24H, which define the inlets 28H of the cavity, farther from the base 72 than the upper ends of the ventilated cavity 24H, which is the outlet 30H of the cavity. Although the lower radiant barrier assembly 2H may have an air flow through its entire inlet 28H, the various barrier assemblies 2H receive ambient air only through the uppermost part of their cavity inlets 28H as indicated by means of arrows 76. A hot air manifold 78 can be mounted adjacent to the outlet 30H of the cavity of the uppermost assembly 2H to, for example, allow the hot air to escape into the ambient atmosphere or be directed directly into the interior of the building 10 ,

that is directed to a heat exchanger.

The low-e element 20 can be used on the inner surface of the barriers 12 in both embodiments of Figures 7 and 8 but they are not shown in the drawings for reasons of clarity. If a low-e 2B element was used, it would be applied to the upper surface of the base 72 below the barrier 12. As a splint element, the 2G and 2H assemblies are typically mounted to the surface 4 of the building by use of ceiling nails, not shown.

Figure 9 illustrates another embodiment of the invention in which assembly 21 includes a barrier 12 and support assembly 14H in the form of a fluid permeable substrate. The fluid permeable substrate 14H may have, for example, a horizontally oriented tube or an air porous strip, preferably of the order of approximately 12.5 cm (5 inches) in width by approximately 1.25 cm (0.5 inches) approximately thick The position of the low-e element 20 with the embodiment of Figure 9 can be found on the inner surface 18 of the barrier 12 or on the surface 4 of the building, or both, depending mainly on the type of material used as a permeable substrate. fluid. If used with a flat roof, it is desirable to use something that can help to extract ambient air between the barrier 12 and the surface 4 of the building, that is, through the fluid permeable substrate 14H. The embodiment of Figure 9 illustrates the use of a conventional passive-operated vent 80. Instead of a vent, a fan or other type of air pump could also be used, and heat can be extracted to be used by the building.

Figures 10A and 10B illustrate two additional embodiments of the invention in which the radiating barrier assemblies 2J and 2K are shown mounted in a hooked ceiling system or other type of undulation. The roof system includes projecting joints 82 separated by substantially flat panels or channels 84. In the embodiment of Figure 10, the barrier 12 is mounted on a pair of projecting joints 82 and extends thereon so that the joints projections are arranged below and possibly hold the support assembly. In the embodiment of Figure 10A, independent supports 16K are used to secure the barrier 12 between pairs of projecting joints 82.

A preferred method for manufacturing the radiant barrier assembly 2 includes the steps of selecting a barrier, preferably a PV module having an inner and outer surface 18, 22, and adhering a low-e element 20 to the inner surface. A support assembly 14 is then mounted to the barrier 12 to create the assembly 2. This assembly can then be installed in the field directly to the surface 2 of the building. One or more additional low-e elements 20A, 20B may be used in the system installation. The support assembly can be fixed to the building surface in different ways, including the use of adhesives, fasteners, Velcro type fasteners, and other appropriate methods. Also, if the building surface includes a continuous insulation layer, the support assembly 14 may be designed to include an area of the support assembly embedded within the continuous insulation layer and that extends outwardly and upwardly through the outer surface of the insulating layer so that the insulating layer itself helps to secure the radiant barrier assembly to the building. In some situations, the inner surface 18 of the barrier 12 will not include the low-e element 20; in these situations the low-e elements 20A and / or 20B can be used separately from the surface 18 to create the desired thermal insulation of the building 10.

The assembly may also comprise a fastener (62) with a base attached to the support assembly, the base having an outer base surface that is positioned so that said ventilated cavity is formed between the inner surface of the barrier and the surface base exterior.

The base may comprise a layer of a thermal insulating material, and the part of the support assembly may be embedded within the thermal insulating material.

In addition, the barrier may comprise a photovoltaic module and the base may be substantially larger than the barrier so that said assembly is in the form of a board to allow said assembly to be attached to the surface of the building.

Claims (21)

one.

 Radiant ventilated cavity barrier assembly (2, 2A – K), which can be mounted on a surface of a building (4), comprising:

a barrier (12) configured as a panel having an inner and outer surface (18; 22); a support assembly (14, 14E, 14F, 14H) attached to the barrier (12) and extending inwards with respect to the inner surface (18), the support assembly having a separate part of the inner surface (18) ) and which can be attached to a surface of the building to form a ventilated cavity (24, 24E-24H) that is created between the surface of the building (4) and the inner surface (18) and induce a flow of air through the cavity (24, 24E-H); and a low-emissivity element (20, 20A, 20B) located on the inner surface (18), and / or suspended within the ventilated cavity to be formed between segmented supports (16) of the support assembly (14, 14E, 14F, 14H).

2.

 Radiant barrier assembly of ventilated cavity (2, 2A, 2K), the assembly (2, 2A, 2K) being mounted on a surface of a building (4) and comprising:

a barrier (12) configured as a panel having an inner and outer surface (18; 22), a support assembly (14, 14E, 14F, 14H) attached to the barrier (12) and extending inwards with respect to the inner surface (18), the support assembly (14, 14E, 14F, 14H) presenting a separate part of the inner surface (18) and attached to the building surface (22) to form a ventilated cavity (24, 24E-H) that is created between the building surface (4) and the inner surface (18) to induce a flow of air into the cavity (24, 24E-H), and a low-emissivity element (20, 20A, 20B) which is located on at least one of the interior surface (18), the surface of the building (4), and between the interior surface and the building (4; 18) and separated from them.

3.

 Assembly according to claim 1 or 2, characterized in that the barrier (12) comprises at least one of a photovoltaic module on the outer surface of the solar reception (22) of the barrier (12) and a panel of thermal isolation; The support assembly (14, 14E, 14F, 14H) is attached to the inner surface (18).

Four.

 Assembly according to claim 1 or 2, characterized in that the outer surface is a surface of high reflectivity and high emissivity, and in which the part of the support assembly (14, 14E, 14F, 14H) comprises minus one of:

an adhesive application surface to which an adhesive (38) can be applied to allow the part to adhere to a surface of a building (4); a Velcro type fastener; Y a fixing element (46).

5.

 Assembly according to claim 1 or 2, characterized in that the outer surface of the barrier (12) comprises a photovoltaic panel zone in a first angular orientation and a reverse angle zone (56) in a second angular orientation.

6.

 Assembly according to claim 1 or 2, characterized in that said support assembly (14, 14E, 14F, 14H) comprises at least one of the following:

mutual coupling elements to allow mutual connection of the adjacent of said assemblies; a fluid permeable layer (14H) that makes contact with the inner surface and filling at least substantially the ventilated cavity; a plurality of thermal insulation blocks; a plurality of separators and associated fasteners; Y first and second legs of mutual coupling so that the first leg of one of said barrier assembly radiant can be coupled to the second leg of an adjacent to said radiant barrier assembly; a crimped roof panel; Y a corrugated roof panel.

7.

 Assembly according to claim 1 or 2, characterized in that said low-emissivity element (20, 20A, 20B) has an emissivity not greater than 0.4.

8.

 Assembly according to claim 1 or 2, characterized in that the outer surface (22) is substantially parallel to the surface of the building.

9.

 Assembly according to claim 1 or 2, characterized in that it further comprises means for inducing a flow of air through the ventilated cavity.

10.

 Assembly according to claim 1 or 2, characterized in that: the radiant ventilated cavity barrier assembly can be mounted on an inclined surface of a building (4); the ventilated cavity has an inlet of the cavity (28, 28E-H) and an outlet of the cavity (30, 30E-H), at least part of said exit of the cavity (30, 30E-H) being higher than the entrance of the cavity in order to favor the flow of air through the ventilated cavity (24, 24E-H).

eleven.

 Assembly according to claim 1 or 2, characterized in that it further comprises an actuator of air flow (80) connected to the ventilated cavity (24, 24E-H) to push air through the ventilated cavity.

12.

 Procedure for carrying out a radiated barrier assembly of ventilated cavity (2, 2A-K) comprising the following stages:

select a barrier (12) having an inner and outer surface (18; 22); place a low emissivity element (20, 20A, 20B) on at least one of the inner surface (18), a surface (4) of a building (10), and between the interior surface and that of the building (4; 18) and separated from them; mount a support assembly (14, 14E, 14F, 14H) to the barrier (12) so that a part of the support assembly (14, 14E, 14F, 14H) extends outwards away from the inner surface (18) ; and fasten the barrier (12) to a building surface (4) using a support assembly (14, 14E, 14F, 14H) thus forming a ventilated cavity (24, 24E-H) between the inner surface (18) and the surface of the building (4).

13.

 Method according to claim 12, characterized in that the step of selecting the barrier (12) is carried out by selecting a photovoltaic module as a barrier (12).

14.

 Method according to claim 12, characterized in that it comprises the step of applying the low emissivity element (20, 20A, 20B) to the inner surface (18).

fifteen.

 Method according to claim 12, characterized in that the clamping stage is performed on an inclined surface of a building (4).

16.

 Method according to claim 12, characterized in that the clamping stage comprises the step of embedding lower ends of elements of the support assembly in a layer of thermal insulation on the building surface (4).

17.

 Method according to claim 12, characterized in that it further comprises the step of selecting a photovoltaic module (PV) as a barrier (12).

18.

 Method according to claim 17, characterized in that it further comprises the step of selecting a support assembly that includes a base that can be mounted against an inclined surface of a building (4), said base having a base surface area at least 20% larger than said PV module.

19.

 Method according to claim 18, characterized in that it further comprises the step of assembling a plurality of said barrier assemblies (2, 2A-2K) with said bases overlapping as slats.

twenty.

 Method according to claim 12, characterized in that it further comprises the step of laterally coupling the adjacent of said barrier assemblies to each other when mounted to said building surface (4).

twenty-one.

 Method according to claim 12, characterized in that the clamping stage comprises the step of increasing the convective air flow through the ventilated cavity (24, 24E-H) creating an inlet of the cavity (28, 28E- H) and an outlet of the cavity (30, 30E-H) to said ventilated cavity and place at least part of the outlet of the cavity higher than the entrance of the cavity.