BACKGROUND OF THE INVENTION 
       [0001]    The invention relates to a modular construction element used to close a building roof, in particular a flat roof. The invention further relates to a roof comprising at least one modular element according to the invention. 
       DESCRIPTION OF THE PRIOR ART 
       [0002]    Conventionally, building roofs, for example of warehouses or factories, take the form of flat roofs. In certain cases, it may happen that these roofs are closed by roofs of substantially prismatic shape, which are called shed roofs. More precisely, these roofs have translucent portions comprising glass panes arranged so as to be steeply inclined on the north side for the purpose of obtaining diffuse light inside the building, better known by the name “skylight”. Furthermore, these roofs may include a solar collector, placed for example so as to be oriented facing south, this particular orientation enabling the solar collector to be more effective. Such a roof is known in particular from document DE 25 59 226. 
         [0003]    However, the construction of such a roof having several separate construction components is complicated and its design by architects depends on the dimensions of the building. This is because the integration of solar panels on such a structure is complicated if it is desired to ensure cooling, insulation and positioning conditions that allow the panel to operate satisfactorily. Consequently it is necessary to provide upstream of the construction of these roofs, that is to say in the design of such a roof, all the components that will constitute it and to assemble all these components on the construction site. 
         [0004]    In addition, once the components have been positioned, the sealing and the thermal protection of the roof in its entirety are tricky to achieve given the heterogeneous assembly formed by this roof. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention aims to solve completely or partly these drawbacks by providing a modular construction element that makes it easier to produce such a type of roof and to integrate solar panels. For this purpose, the subject of the invention is a modular construction element used to close a building roof, in particular a flat roof, comprising a wall having a first face inclined with respect to a horizontal plane, having at least one transparent or translucent portion suitable for allowing natural light to illuminate the inside of the building; a second face inclined with respect to a horizontal plane, of opposite orientation to the first face, having at least one solar panel comprising at least one photovoltaic module; and at least part of the faces of the modular element comprising at least one thermal and/or acoustic insulation layer. 
         [0006]    Thanks to the arrangements according to the invention, the production of such a modular element allows the number of solar panels and the overall illumination area to be adapted to the dimensions offered by the building roof, while still ensuring thermal and/or acoustic protection on the roof. The term “overall illumination” comprises direct illumination, diffuse illumination and albedo illumination. 
         [0007]    According to one embodiment of the invention, the modular construction element comprises sealing means designed to allow continuity of sealing between the modular element and the roof when the modular construction element is positioned on the roof. 
         [0008]    This feature provides continuity of sealing over the entire contact area in the modular element and the roof when the modular construction element is positioned on the roof. 
         [0009]    According to one embodiment, the thermal and/or acoustic insulation means comprise glass wool. 
         [0010]    This feature has the benefit of being simple to implement since glass wool is flexible from the mechanical standpoint and is advantageous in terms of weight and cost compared with other materials. 
         [0011]    Advantageously, the thermal and/or acoustic insulation means comprise a double-glazing unit. 
         [0012]    These arrangements provide acoustic insulation and thermal insulation. 
         [0013]    According to one feature of the invention, the first face makes an angle of between 20° and 50°. 
         [0014]    Such an inclination of the solar panel provides optimum efficiency of the photovoltaic modules placed on the surface of the solar panel. 
         [0015]    According to one embodiment, the second face makes an angle of greater than 60° to a horizontal plane. 
         [0016]    This arrangement makes it possible to provide diffuse light inside the building. 
         [0017]    Advantageously, the modular elements comprises gutters for recovering the condensation water. 
         [0018]    Preferably, the modular construction element includes a cooling passage provided at the rear of the solar panel in the second face. 
         [0019]    The invention further relates to a roof comprising a framework having at least one housing and at least one modular element according to the invention accommodated in the housing of the framework. 
         [0020]    Thanks to the arrangements according to the invention, a roof of the type described above may be produced simply by constructing a framework having openings forming accommodating housings for at least one element according to the invention and then by positioning such an element in each housing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    In any case, the invention will be fully understood with the aid of the following description, with reference to the appended schematic drawings representing, by way of nonlimiting example, one embodiment of this modular construction element: 
           [0022]      FIG. 1  is a perspective view of a modular construction element on the side not exposed to sunlight, with protective glazing; 
           [0023]      FIG. 2  is a perspective view of a modular construction element, in a second angle of view opposite that of  FIG. 1 , namely on the side exposed to sunlight, with a solar panel; 
           [0024]      FIG. 3  is a cross-sectional view in a vertical plane passing through the line III-III of  FIG. 2 ; 
           [0025]      FIG. 4  is a sectional view of a photovoltaic skylight with recovery of the heated air; and 
           [0026]      FIG. 5  is a schematic cross section of an industrial site equipped with warm-air recovery in winter and cool-air ventilation in summer. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0027]    As shown in  FIGS. 1 to 3 , a modular construction element  1  according to the invention comprises a body having a wall formed by a first face  2  inclined to a horizontal plane, a second face  3  inclined to a horizontal plane and a strip  4 . The orientation of the second face  3  is opposite that of the first face  2  so that the two faces  2 ,  3  have substantially the shape of an inverted V, seen in cross section perpendicular to the plane of the faces. The apex of this inverted V is truncated, the two faces being joined by the flat horizontal strip  4 . 
         [0028]    The modular element  1  also includes two lateral faces  5  placed transversely with respect to the first and second faces  2 ,  3  and to the strip  4 . 
         [0029]    This wall defines a downwardly open space, the edge of the downward-facing opening consisting of the lower edges of the first and second faces  2 ,  3  and of the lateral faces  5 . The edge of the opening is surrounded by a flat outer rim  10 . 
         [0030]    As illustrated in  FIG. 3 , the second face  3  is placed so as to be more inclined than the first face  2 . Advantageously, the first face  2  makes an angle a of greater than 60° with a horizontal plane. Preferably, the second face  3  makes an angle b of between 20° and 50° with a horizontal plane. 
         [0031]    The first face  2  includes square or rectangular openings  6  which accommodate translucent or transparent surfaces  11 . The surfaces  11  are made using a transparent or translucent material, for example glass. Preferably, the surfaces  11  comprise a double-glazing unit to improve the thermal and acoustic insulation. Preferably, these surfaces  11  comprise reinforced frosted glass in order to comply with visual and anti-intrusion protection. 
         [0032]    Such a material is used for the purpose of illuminating the interior of the building with natural light, depending on the skylight of the shed roof. In addition, the use of a double-glazing unit provides the modular element  1  with good acoustic insulation and also good thermal insulation. 
         [0033]    Preferably, the first face  2  is placed so as to be oriented towards the north side in the northern hemisphere. Such an orientation allows the transmission of diffuse light into the building. 
         [0034]    As shown in  FIG. 1 , the portions  11  include a protective mesh  12 . The protective mesh  12  is placed on top of the flat  9 . This protective mesh  12  is intended for example to prevent break-ins. According to a variant, the portions  11  are equipped with reinforced antibreak-in glass. 
         [0035]    As illustrated in  FIG. 2 , the second face  3  has accommodating locations  13  for a solar panel. As shown in  FIG. 2 , the second face  3  has four such locations. The accommodating locations  13  are of rectangular shape, the width of each accommodating location  13  being parallel to the horizontal plane. Positioned in this location is a frame for accommodating the solar panel so that the rear of the panel is facing an opening in the wall. More precisely, they are arranged beside one another in a direction parallel to the horizontal plane. A solar panel  15  is placed in each accommodating location  13 . Each solar panel  15  comprises a set of photovoltaic modules. Each photovoltaic module comprises at least one photovoltaic cell or a set of photovoltaic cells connected together electrically. 
         [0036]    Preferably, the second face  3  is placed so as to be oriented towards the south. Such an orientation provides good photovoltaic efficiency. 
         [0037]    In a version with simple natural convective cooling, the second face  3  comprises, near each solar panel  15 , two openings, namely  16  and  17  respectively, of approximately rectangular shape. The length of each opening  16 ,  17  is approximately parallel to a horizontal plane. More precisely, the wall has an opening  16  located at the top and an opening  17  located at the bottom of each solar panel, so that the two openings  16 ,  17  and the solar panel  15  are aligned. It should be noted that the length of each opening  16 ,  17  is approximately equal to the width of the solar panel  15  close to where they are located. A fine-mesh grille  18  is placed on each opening  16 ,  17  in order to prevent the penetration of insects or other pests. 
         [0038]    As shown in  FIG. 3 , an additional face  20  is placed to the rear of the solar panel  15 . The additional face  20  is approximately parallel to the second face  3 . These arrangements make it possible to provide a passage  21  to the rear of the solar panel  15 . The passage  21  is connected to the two openings  16 ,  17  situated near the solar panel  15 . 
         [0039]    It is important to recall that during the operation of the solar panels  15  the photovoltaic cells placed in sunlight heat up. Since the heat reduces the efficiency of the photovoltaic cells, it is necessary to prevent them heating up inopportunely. Thus, the arrangement of such a passage  21  has the considerable advantage of allowing ventilation to the rear of the photovoltaic panels  15 , this ventilation taking place by natural convection. This ventilation enables heat exchange between the solar panel  15  and the ambient air and consequently cools the solar panels  15 . 
         [0040]    According to a more elaborate alternative embodiment of the invention, shown in  FIG. 4 , the modular element  1  may include a system of connections  28  between the passages  21  located to the rear of the solar panels  15  and the interior of the building. These arrangements make it possible to take advantage of the air heated by the solar panels  15 . The air thus heated in the passages  21  would be injected into the interior of the building, heating it up in winter for example.  FIG. 5  shows symbolically and by way of example a cross section of industrial premises equipped with an alternative embodiment of the invention with recovery of the heated air for ventilation in winter.  FIG. 5  also shows symbolically the cooling of the building by the circulation of fresh air  29  in summer and the expulsion of the hot air  30  to the outside. 
         [0041]    The additional face  20 , the strip  4 , the first face  2  and the lateral faces  5  of the modular element  1  form an assembly having an internal surface  22  and an external surface  23 . The internal surface  22  is intended to be oriented towards the interior of the building once the modular element  1  has been placed on a building roof  24 . The external surface  23  is intended to be in contact with the exterior of the building. 
         [0042]    Thermal insulation means are placed on the internal surface  22  of the assembly as defined above, with the exception of the openings  16 ,  17  of the second face  3 . 
         [0043]    The thermal insulation means comprise a thermally insulating material. It should be clearly understood that the choice of thermally insulating material will preferably be glass wool  25 , which is advantageous in terms of weight and cost compared with other materials and is also flexible from the mechanical standpoint and is simple to use. 
         [0044]    The glass wool  25  has sufficient thickness to ensure both good acoustic insulation and good thermal insulation. 
         [0045]    The positioning of the modular construction element  1  on the flat roof  24  defines a contact surface  26  between the modular element  1  and the flat roof  24  at the rim  10 . Sealing means are provided over the entire contact surface  26 , i.e. at the interface between the modular element  1  and the flat roof  24 . In particular, these sealing means comprise a gasket  27 . This gasket  27  is intended to provide continuity of sealing between the modular element  1  and the flat roof  24  when the modular construction element  1  is positioned on the roof. This gasket  27  is intended to prevent any loss of heat from the interior to the exterior of the building or any ingress of water via the roof into the building. 
         [0046]    According to a variant, the first face  2  is equipped with gutters, which are not shown in  FIG. 1 ,  2  or  3 . Symbolically, the gutters for recovering condensation water are shown in  FIG. 4  by evacuation holes located at the bottom of the double wall to the rear of the photovoltaic modules. The gutters are placed near the solar panels  15  and preferably beneath the solar panels  15 . Their purpose is to recover water that condenses on the surface of the solar panels  15 . 
         [0047]    In order to place such a modular construction element on a flat roof of a building, a framework (not shown in the drawing) is used. The framework comprises a housing in which the modular element is placed. The framework is intended to close the roof of the building. 
         [0048]    Although the invention has been described in conjunction with particular exemplary embodiments, it is obvious that the invention is in no way limited thereby and that it comprises all the technical equivalents of the means described and also their combinations if these fall within the scope of the invention.
The invention relates to a modular construction element used to close a building roof, in particular a flat roof, comprising a first face inclined with respect to a horizontal plane, having at least one transparent or translucent portion suitable for allowing natural light to illuminate the inside of the building; a second face inclined with respect to a horizontal plane, of opposite orientation to the first face, having at least one solar panel comprising at least one photovoltaic module; and at least part of the faces of the modular element comprising at least one thermal and/or acoustic insulation layer.