GB2124268A - Self-supporting extra-long truss element for roof construction - Google Patents

Abstract

An extra-long self-supporting truss element (1 Fig. 3) for the construction of a roof of a building consists of a self-supporting frame made of metallic components 9, 11, 12 which extend continuously between the two longitudinal edges (5, 6 Fig. 3) of the element and its ends (7, 8, Fig. 2b) and an insulating covering obtained by the juxtaposition of several sections (27, 28 Fig. 3) being a composite consisting of an exterior cover (3, Fig. 3) an interior cover (4 Fig. 3) and an intermediate insulating filling of fire-resistant foam (2 Fig. 3). <IMAGE>

Description

SPECIFICATION Self-supporting extra-long truss element for roof construction This invention relates to an extra-long, selfsupporting truss element for use in the construction of the roof of a building and which is particularly suited for industrial and commercial buildings, schools and sports buildings, as well as roofs which are constructed by placing several of these elongate elements in parallel side-by-side contacting relationship.

In addition, the invention relates to an insulated extra-long self-supporting truss element, which incorporates multiple technical functions such as lighting, heating, etc. which a building to be covered must conventionally include.

Discussion of prior art It is known to cover buildings using extra-long self-supporting elements which are assembled side-by-side in contacting relationship in such a way that they span the complete roof on which are assembled end to end and in parallel contacting relationship with other end-to-end positioned elements to form a roof made of several rows of juxtaposed elements.

These self-supporting elements are very often factory equipped with devices assuring future technical functions of the building, such as insulation, lighting, heating or fire protection.

Thus, the completions which have to be made at the worksite are reduced to a minimum.

Indeed it is sufficient to bring such elements to the work site and install them on an existing supporting structure (a basic structure of metal or concrete), to assemble them side-by-side and if required also end-to-end and to then connect the technical facilities of each element to electrical outlets, steam or hot water, for example, so that the building is entirely equipped and at the same time, is insulated and protected against the weather.

The self-supporting elements presently used for the roofing of buildings are either made of concrete or of sheet steel covering an insulating blanket of fibre-glass secured to the exterior sheet and to which, in most cases, technical facilities are integrated and which themselves assist in the support of the sheet steel components and the insulation blanket.

The elements made of concrete have the obvious disadvantage of being particularly heavy; the elements constructed of sheet steel have the disadvantage of being difficult to manufacture and accordingly expensive.

Objects of the invention The purpose of this invention is to provide a new type of self-supporting element which is light, easy to manufacture, simple and quick to install, which results in a self-supporting element that is of low-cost.

For this purpose, the invention provides an extra-long, self-supporting element for the construction of roofs of buildings which consist of: (a) a structure of metallic elements extending continuously between the two longitudinal sides of the element as well as between its ends in order to ensure the self-supporting property of said element, and (b) an insulating covering achieved through the juxtaposition of several sections that can be removed and replaced individually, the covering being mounted on and fixed to the metallic structure with each of the sections being a composite consisting of an exterior corrosion-resistance surface or sheet, an interior surface or sheet which has largely the same configuration as the exterior surface, and between the sheets an insulating layer or blanket obtained by the injection and subsequent polymerization of a foam having good fireresistant and adhesive properties.

In order to guarantee excellent resistance to all types of corrosion and particularly to atmospheric damage, the exterior covering or sheet is preferably made of aluminum sheeting, precoated or enamelled aluminum or of aluminum composition.

Even though the question of resistance to corrosion does not arise in the same way where the interior covering or sheet is concerned, the latter should also preferably be made of precoated aluminum sheeting due to its excellent properties of humidity resistance and its relatively low weight which adds to the self-supporting characteristics of the element by avoiding unnecessary weight on the supporting metallic structure.

However, as an alternative, the interior covering could be made of pre-coated steel if the structure were to be left uncovered or of galvanized steel if a ceiling were to be installed under the metallic structure to cover it.

The insulation blanket sandwiched between the exterior and interior sheets or covers is obtained by injection and subsequent polymerization of a foam such as polyurethane or phenolic.

In a particularly advantageous design, the structure of metallic components of the selfsupporting element consists of three parallel, tubular chords which stretch longitudinally and continuously between the two ends of the elements, one of the chords is a tie-chord arranged centrally on the symmetrical longitudinal plane of the element two side chords arranged laterally which constitute longitudinal sides of the element, web braces or web ties which are arranged on either side of the tie chord in symmetrical relatiqn to said longitudinal symmetrical plane of the element, and which web braces connect the tie-chord with the two lateral side chords.

In addition, the web braces either stretch from side-chord to the tie-chord or extend continuously from one side chord to the other and which are of one piece with the tie-chord in the middle.

Furthermore, the web braces all have largely the same angle of inclination in relation to transverse planes of the element which are planes perpendicular to the longitudinal axis of the element.

Finally, the web braces are arranged in a zigzag, alternately inclined towards the front and the back of the element, the connecting points of each web brace on the tie-chord and on one or both of the two side chords being joined at the connecting points of the adjacent web braces to the tie-chord and the chords respectively.

The structure described above is perfectly balanced since on the one hand it is symmetrical in relation to its central tie-chord and, on the other hand, it is of regular geometry on its whole length through the arrangement of its web braces inclined at the same angle.

In its most advantageous construction the selfsupporting element made according to the invention, presents itself, in a cross-section, in the shape of a V open at the top, whose longitudinal symmetrical plane is vertical and crosses the longitudinal axis of the tie-chord, the web braces being welded to said tie-chord defining on either side of the latter a plane called a slope, inclined about 450 on a horizontal plane, with the web braces extending to the lateral chords to which their tips are welded, the two lateral beams then forming the top of the metallic panel structure.

In the case where the web braces stretch continuously from one chord to the other, their median zone, by the back of which they are welded to the tie-chord is advantageously curved and the concavity turned upwards to hold a gutter.

The insulating covering of the element according to the invention supported by the metallic structure consists of: a) a central gutter overlapping from the base of the element resting on the tie-chord and the base of the web braces; b) two panels overlapping the two slopes of the element, and resting on the principal rafters being joined to the gutter in such a way as to ensure air and water-tightness; c) two caps each overlapping from the top of an element and the top of a second, adjacent element after being assembled on said first element, each cap resting on the tip of the web braces and the chord as well as on the same component parts of the second adjoining element, being attached to the panels in such a way as to ensure air and water-tightness.

In order to avoid any infiltration of rainwater in the bottom of the gutter which could harm the absolute insulation of the building through its roof, the said gutter is very long and extends in a continuous manner or in sections at least ten meters long from one end of the element to the other.

In order to facilitate the maintenance of the roof, it would also be advantageous to design it in sections which can be removed and replaced individually; therefore, the panels and caps are constructed in short elementary sections, the panel sections being solid and opaque or open and equipped with a skylight contributing to the natural lighting of the building.

Furthermore, since the structure is very balanced, it is possible to replace a blind panel with a containing a skylight and vice-versa.

In order to make each section of the insulating covering easily removable and individually replacable, the panels are tightly joined to each other by interior keys and exterior clips and the cap sections are also tightly joined to each other by interior keys and exterior clips.

Through the design defined above, the selfsupporting element according to the invention has another advantage: it can be assembled completely at the factory with the exception of the cap sections, of course, which in any case are only installed at the work site once the selfsupporting elements of the invention have been joined to each other, or it can be assembled only at the construction site by applying and joining the different component parts of the insulating cover to the basic structure delivered bare.

The modular and repetitive design of the panels and the cap sections allow these parts to be manufactured in the plant and then to be shipped go other continents by container, either by air of by sea, due to the compactness of these containers.

In case the construction with self-supporting elements according to the convention is desired at a great distance from the place of manufacture, it would be very easy to build only the metallic structure at the plant and later on assemble the panels, the cap sections and the gutters, shipped by container, on the spot.

Given these aforementioned possibilities, the applicant for patent has found it essential to simplify the assembly of the different component parts of the insulating cover on the selfsupporting basic structure.

For this purpose, the component parts of the insulating cover are designed in such a way that the gutter is first fixed to the web braces, after which the panels are fitted in the gutter and are affixed to the web braces and finally, the cap elements are fitted into the panels and are attached onto said panels by clips.

With this type of assembly, the means of attaching the gutter and the panels to the web braces consists of clamps which, ideally, do not go through the insulating blanket; thus, as the clamps in themselves do not constitute thermic points harmful to the insulation desired, the roof obtained by using the methods of the invention is completely insulated.

In order to better explain the purpose of this invention, we will now describe preferred forms of implentation which are to be considered only as examples of a purely illustrative and non-limiting nature.

Brief description of drawings Figure 1 presents a perspective of the selfsupporting element of the invention seen by its extremity before after removal of the fronton elements.

Figures 2a, 2b and 2c represent the (basic) metallic structure ensuring the self-supporting property of the element seen in perspective, from underneath and from the side, respectively.

Figure 3 represents an end view of an alternative to the self-supporting element of the invention, an alternative version in which the web braces each only extend to a slope of the element, from a high side chord to a low central tie-chord on its left half, the element is shown covered at the end by a fronton.

Figure 4 represents a view of the longitudinal section in the axis of the gutter, of the front part of the self-supporting element according to the invention.

Figure 5 represents a cross-section of the interlocking of a panel into the gutter.

Figure 6 represents a cross-section of the lateral liaison of two adjoining panel along the same slope of the self-supporting element.

Figures 7a and 7b represent, respectively, seen in a vertical axis cross-section and seen from underneath, a device allowing assembly at the longitudinal sides facing the two adjoining selfsupporting elements.

Figure 8 represents, seen in a transversal cross-section, the interlocking of the cap on a panel.

Figure 9 represents a longitudinal section of the insulating cover joined to a fronton element at its extremity.

Figures 10 and 11, respectively, are a transverse section and a perspective view of solar collectors or captors that heat the air space in the interior of the building covered by the assembled self-supporting elements of this invention.

Detailed description of accompanying drawings In the drawings the longitudinal self-supporting element of the invention in its entirety is shown by numeral 1.

The depth of this element is between 4.80 Meters (m) and 48 m, depending on the needs of the building to be constructed. For purely technical and manufacturing reasons it would be advantageous for this length to be multiple of 2.40 m.

In this respect, at least in France, the length of 21.60 m would be one of the most common lengths since it would correspond to the "transportable length" authorized by the law governing the roads.

In its most conventional construction, element 1 presents an overall width of 2.40 m and an overall height of 1.15 m for the supporting metallic structure, and an overall height of 1.20 m for the structure covered by its insulating covering, as we will explain in detail below, each of its sections is formed by an injected foam blanket 2 sandwiched between an exterior covering 3 and an interior covering 4.

The self-supporting property of element 1 is ensured by the basic structure of components shown in figures 2a-2b and 2c, said basic structure extending continuously between the two longitudinal sides, respectively left 5 and right 6 of the element 1, as well as between its transversal ends, respectively front 7 and rear 8, in order to precisely ensure the self-support no matter what the length of each element 1.

This structure of components consists of: a) a tie-chord 9 arranged centrally in the symmetrical longitudinal plane 10 of the element 1 and extending continuously between the two transverse sides 7 and 8; this tie-chord is tubular, and for the implementation of the self-supporting structure of 24 linear meters it could for example, be constructed from a tube of 3.2 mm thickness for a circular section of a 88.9 mm diameter, or from a 4 mm thick tube of square section with 90 mm sides.

b) of two identical chords arranged laterally and each constituting a longitudinal side, respectively left 11 and right 12 of element 1; these two chords are parallel to tie-chord 9 and they also extend cdntinuously throughout the length of the element; the two chords 11 and 12 are tubular, and as an example, for the construction of a carrying structure of 24 linear meters, they could each be made from 24 linear meters, they could each be made from a 2.9 mm thick tube with a circular section of 76.1 mm, or from a 3.2 mm thick tube of square section with 70 mm sides.

c) of web braces arranged on either side of tiechord 9, symmetric in relation to the longitudinal symmetrical plane 10 of element 1, and that connect said tie-chord to the two chords 11 and 12; In the alternate design of figure 3, the web braces 1 3 each extend from a chord to the tiechord and in this case, especially if the tie-chord and the chords are cylindrical tubes, it is particularly advantageous to weld from point to point on these three longitudinal chords 14 in the shape of an overturned V or of valley and flats 1 5, respectively to the tie-chord and the chords in order to facilitate the welding of the extremities of the web braces 1 3 to tie-chord 9 and chords 11 and 1 2 respectively.

In the following description of the tie-chord 9, side chords 11 and 12 and web braces 13, 113 may alternatively be referred to as tie-beam, beams and principal rafters respectively but the same component parts are intended.

In the variation presented in figures 2 and 4, the web braces 113 extend in a continuous line from one chord to the other, being, in their middle, of one piece with tie-chord 9; in both cases, each web brace is tubular and for the construction of a self-supporting structure of 24 linear meters it could well be made with a 2.7 mm thick tube having a square section of 45 mm sides; preferably the web braces 13 and 113 would all be inclined by largely the same angle in relation to the planes of the right section 16 of the element, planes which by definition extend parallel to sides 7 and 8 or may also extend orthogonally to the three tubular longitudinal ribs 9,11 and 12; the web braces 13 or 113 are then arranged in zig-zag as is made particularly clear by figures 2 and 4, in which the web braces are represented alternately inclined towards the front (1 13a) and towards the back (1 13h) of the structure; the separate parts 14 and 1 5 are then shared each by two web braces 1 3 which follow each other immediately along the structure and on each slope of the latter; by the same token, the contact points of each web brace 113 with the tie-chord (welding 17) and the two chords (welding 18) are connected to the contact points of the adjacent web braces at tie-chord 9 and chords 11 and 1 2 respectively.

It should be noted that regardless of the design of the web braces adopted, be it web braces 113 extending in a continuous line from one chord to the other and being welded to tie-chord 9 in their middle, or the web braces 13 extending only between the tie-chord and a lateral chord 11 or 12, the basic structure of the metallic panels is essentially symmetric and balanced, symmetric in relation to the vertical longitudinal plane on the one hand, balanced with the side in front of 7 and the side behind 8 through the alternate inclination of the web braces on the other hand.Thus the basic structure erected in this way has the double advantage of: presenting the same characteristics of mechanical resistance all along its length, and presenting two slopes, a left and a right, which are absolutely identical, which will simplify the installation even more-whether it be at the plant or at the construction site-since the skylights will be fixed on the slopes which are the most exposed to the North without having to pay any special attention to its arrangement-left or right-of the basic structure since the latter is symmetrical in its design.

In the area of ends 7 front and 8 back, at right angles to the part respectively in front of 1 9 and behind 20 of the structure in concrete or metal on which the two extremities of the metallic structure described above will rest, an end diagonal front 21 and rear 22 respectively, also ensures the connection between the two lateral chords and the center tie-chord, either by extending in a continuous line from one chord to the other, or by extending in two sections each going from the tie-chord to a side chord.

The web braces 13 or 113, and to a lesser degree the supports 21 and 22, serve to add to the self-supporting properties of the structure and to eliminate the sharp stress which is put on the latter transversally. Consequently the web braces 13 or 113 are arranged along the three ribs 9-11 -12 in a number of sufficient to assemble the three ribs rigidly, so that they are perfectly parallel along the full length of each element 1 and that in this manner the self-supporting property is guaranteed.

In this regard, in the construction which from an industrial point of view seems to be the most interesting, one places the three chords as illustrated in figures 1 and 4, i.e. the central tiechord 9 in the low position and the two lateral chords 11 and 12 in the high position.

Thus, after assembly, seen from the end, the element has the shape of a V open at the top, a V whose symmetrical plane 10 is vertical and crosses the longitudinal axis of tie-chord 9.

The web braces 13 or 113, connected to tiechord 9 by separate parts 14 or welded directly to said tie-chord, define on each side of the latter two planes called "slopes" which, of course, are symmetrical in relation to vertical plane 10 and which are inclined about 450 on plane 10 as well as on the horizontal plane.

In the construction described above the tiechord constitutes the base line of the structure and the two lateral chords constitute the tops.

The tie-chord thus has to support the gutters to catch the rainwater and chords 11 and 12 must each, after assembly with the beam opposite the adjacent self-supporting element on the roof that has been constructed, take the cap elements overlapping from the said two chords opposite and the devices which rigidly ensure their assembly.

The rainwater gutter has a rounded bottom so that the water can carry away any stones or moss that might, accidentally or not, have gotten into the gutter. The web braces are also rounded in their central part by the back of which they are welded to the upper side of tie-beam 9.

Consequently, as can be seen especially in figure 2a, each principal rafter 113 is curved in its low median part, the rounded part being concave and turned upwards. This central, rounded panel extends on either side after a rectilinial part, inclined about 450 on the horizontal, each belonging to a slope, and extending all the way to a lateral beam on which the tip of the principal rafter is welded in 18.

The principal rafters 1 3 or 11 3 being arranged in a zig-zag, inclined alternately towards the back and the front of the structure, they define all along the latter a distance P visible especially in figures 2, a distance that corresponds to the intervals which separate the liaison points ofthe principal rafters with each of the beams 11 or 12 or corresponds to the intervals which separates the liaison points of the principal rafters with the tiebeam 9.

In the most interesting structure both in regards to the simplicity of its manufacture, its mechanical resistance and its self-supporting properties over very great lengths, distance P is equal to the width of element L, i.e. equal to 2.40 m.

Width L means in this case the distance which separates the vertical symmetric axis 23 of the assembly devices in the upper part of the roof from a first element on its adjacent element of the symmetric vertical axis 23 from the other assembly devices of said first element on its other adjacent element.

The assembly devices in question represented in their entirety by reference 24 in figures 7, 8 and 10, having a width of 8 cm, the width of the structure measured between the exterior ribs of the two high beams, left 11 and right 12 respectively, therefore equals L minus 8 cm or 2.32 m. However, in order to simplify the comprehension of the description that follows, these outer ribs will most often be assimilated to the longitudinal sides of each element 1 by which it must be attached to its adjacent elements.

In the preceding preferable construction where L equals P, and where the slopes of each element of the roof are inclined 450 on the horizontal, angle a' formed by each principle rafter 1 3 or 113 in relation to the planes of the right section 1 6 as a result also largely equals 450.

With the previous dimensions given as an example for tie-beam 9, the beams 11 and 12 and the principal rafters 13 and 113, the basic structure built to be self-supportive over at least 24 linear meters, with the distance P and width L equalling 2.40 m, is still extremely light which accounts for its two principal advantages: low cost for both manufacture and transport, easier handling both during transport and at the time of installation on top of structure 1 9-20 which will carry the roof.

The metallic structure such as described previously in fact weighs only 1 2.5 kg per m2 horizontally; despite this low weight, the structure in question is capable of holding up, in France, in the hardest and most exposed areas, i.e. climatic zones classified "3" in which roofs have to be able to withstand snow and wind.

Underneath the self-supporting structure which has been described, there is an insulating cover obtained by the juxtaposition of several lightweight panels, individually removable and replaceable in order to facilitate maintenance service of the roof built in accordance with this invention.

In order to be at once insulating, resistant to bad weather and as light-weight as possible, each component part of the cover is a composite constituted by an exterior covering 3, which resists corrosion, an interior covering 4 largely of the same configuration as the exterior covering and running parallel and under the exterior covering and lastly an insulating blanket 2 obtained by injection and subsequent polymerization of a foam of good fire-reistant and adhesive properties.

The exterior covering 3, for example, is made of aluminum sheeting, preferably pre-laquered aluminum alloy, or else of any other material able to resist saline fog, corrosive atmospheric conditions, sand storms and any other atmospheric phenomena that is damaging.

For the construction of the basic structure already described as an example, the exterior covering of prelaquered aluminum could be made, for example, of a 10/10 mm sheet for the gutter, of 7/10 mm for the panel sections and the cap sections.

As far as the interior covering is concerned, it could be made, for example, from a 4/10 mm sheet, in pre-coated steel or pre-coated aluminum.

This insulating blanket 2, sandwiched between exterior covering 3 and interior covering 4 is obtained by injecting a foam between the two coverings, the foam's subsequent polymerization and simultaneous adhesion to the two coverings.

Taking into account the properties of phonic and thermic insulation, fire-resistance and good adhesion to the metal which the insulating blanket 2 must have, the injected foam should preferably be of the polyurethane or phenolic type, pure or charged.

The density of the foam blanket 2 would ideally be around 40 to 60 kg/m3.

Consequently, one would add to the basic ingredients of the polyurethane (i.e. polyol and isocyanate) which has a liquid density of about 1.2, an expansion agent of the Freon type which produces polyurethane foam of the proper density and compactness.

Each of these adhesive primers, also known as "wash primers" adds to the natural adhesive property which a polyurethane foam or a phenolic foam always develop at contact with a metal such as aluminum the moment it foams, i.e. at its polymerization.

All the elements which forms the insulating cover installed and fixed to the basic metallic structure are produced in the sandwich arrangement just described, i.e. they all have the following order: exterior, corrosion-resistant covering+insulating blanket+interior covering.

The component parts constituting the insulating cover are of three types: a) a gutter 25 in shape of a V open at the top, of the same concavity and direction as the center arch present in the central part of the principal rafters 113, said gutter stretching either in one piece between the transversal sides 7 and 8 of each element, or in sections of 10 to 12 meters long attached by air- and water-tight expansion joints.

b) the panels obtained by the juxtaposition of sections, which for the sake of the description will always be called panels; these panels have a constant width of 2.40 m in order to conform to distance P and they are designed with an opening for a skylight 26 on the north flank (panel 27) and without openings on the south flank (panel 28).

c) The caps, left 29 and right 30 respectively, are rounded, come in sections of 2.40 m length each, necessarily installed at the construction site, after the elements of the roof have been affixed to one another, overlapping from the top of a first element and the top of a second adjacent element after its assembly by devices 24 on said first element, with the panels being joined to the gutter and the caps being joined to the panels in such a way as to ensure absolute air- and watertightness between the corrugations of the actual roof, once all the elements 1 are assembled and entirely covered by the insulating cover at the base of the gutter, on their panels and by the caps underneath their longitudinal connecting line.

Whether it extends in one piece from one side of the element to the other or in 10 to 12 m sections connected by an air- and water-tight expansion joint, the gutter 25 especially illustrated in figures 1 and 9, and in detail in figure 5, is always constructed according to the design which will now be described.

The gutter is cast in a mold, also called "conformator", whose transversal section and length are identical to the transversal section and length of the gutter to be produced.

The mold consists of a bottom in the shape of V open at the top, bordered by two longitudinal walls and a top of the same shape as the bottom which fits on the upper part of the four walls bordering the bottom of the mold.

The sheet of metal destined to form the interior covering 4 is placed on the bottom of the mold, then polyurethane wedges of 56 mm thickness are placed at different points. The sheet metal which is supposed to form the outer coverings 3 is placed under the top where it is held in place by vacuum the moment the lid is closed.

The bottom and lid of the mold are then pressed towards each other, using straps or presses, a polyurethane foam is injected into the inside of the mold and after a wait of about half an hour, the polymerization is completed. The mold can now be opened and a perfectly finished and completed gutter be taken out.

In order to produce an ideal gutter which is absolutely water-tight, a mold is used which has two longitudinal walls forming a fold towards the interior in such a way that the foam blanket obtained after injection and polymerization, has V-shaped notches on each of its longitudinal sides in the thickness of the sandwich, as is illustrated in 32 of figure 5.

The interior covering 4 of gutter 25 has a return 33 going back towards the sandwich on each of its longitudinal sides.

The exterior covering 3 of the gutter also has a return 34 of about 3 cm high on each of its longitudinal sides, obtained by folding at 900 towards the top, a return which is supposed to constitute a third water stop.

The metal sheets 3 and 4 as defined above are obtained by shaping with rollers; the coverings extend over the whole length of the gutter to be produced, or more generally by sections of 2 m lengths. In the latter case, the polyurethane foam ensures the continuity between the sheet metal sections thanks to its adhesive properties.

Whether they be opaque or provided with a skylight, each panel 27 or 28, especially illustrated in figures 5 and 8, are always constructed according to the following design: The panels are also produced in a mold, the length and transverse side of which are identical to the side and length of the panel to be produced.

Therefore the mold has an interior length of 2.40 m.

The mold used to produce a panel is of the same type as the one used for making the gutter except for the two longitudinal walls which border the bottom of the mold, the upper longitudinal wall forming a fold towards the interior in such a way that the blanket obtained has a V-shaped notch in the thickness of the sandwich as can be seen at 35. The interior longitudinal wall forms a fold towards the exterior in such a way that the corresponding interior side of the panel has a V shaped projection 36, complimentary to notch 32 of the gutter, a projection which can furthermore be chamfered in 31 to facilitate the interlocking and adjustment.

The exterior covering 3 of panels 27 and 28 has a clamp 37 on its interior longitudinal edge, which in order to overlap from the upper exterior part of the gutter and to allow the fixation of a slip joint running the whole length of the gutter, is formed by a first fold 38 at 1350 a second fold 39 at 1350, parallel to the coverings, and by a return 40, folded at 1350 towards the bottom, a return which consequently rests elastically on the outer covering of the gutter and provides a first water stop over the entire length and the lower part of each panel.

In space 41 situated between clamp 37 of the panel and the upper part of the gutter bordered by return 34, a water-tight joint 42 is integrated, running the whole length of the gutter under clamps 37 of the various panels 27 or 28, joint 42 thus constituting a second water stop. Thus, water-tightness all along the joining line between the panels and the gutter is absolute. The water runs off the slopes of the roof, along the panels, then to the bottom of the gutter and has no possibility to cross the three successive water barriers that have been established, i.e. extremity 40 of ciaw 37, which by virtue of its light weight presses elastically on the exterior covering 3 of gutter 25, then joint 42 running the whole length of the roof, and finally return 34.

Along its longitudinal interior edge, the interior covering 4 of panel 27 or 28 presents a return 43 re-entrant towards the sandwich, a return inclined about 135O in such a way as to be parallel to the return 33 formed on each longitudinal edge of gutter 25.

At their upper parts, the exterior coverings 3 and interior covering 4 of panels 27 and 28 present exactly the same configuration as the exterior and interior coverings of gutter 25, i.e. a return 44 obtained by folding at 900 towards the top by approximately 3 cm and a return 45 reentrant towards the sandwich respectively.

The V-shaped notch in the thickness of the sandwich all along the upper longitudinal edge of panels 27 and 28 having a configuration identical to notch 32 formed on each longitudinal edge of gutter 25, the upper parts of the panels and the gutter are consequently absolutely identical, as is clearly illustrated in figures 5 and 8.

Details 35-45 and 44 respectively correspond to details 32-33-34 of the gutter.

The principal rafter 1 3 or 113, on each slope of each element of the roof, serving as support for the panels and the rectilineal lateral part of the gutter, the interior coverings 4 of the panels and the gutter are naturally coplanar, as is shown in detail in figure 5.

In order to respect this coplanar arrangement of coverings 4 of the gutter and the panels on the one hand, and to promote, thanks to the flexibility of claw 37 made of thin aluminum, the pressure of return 40 on the exterior covering 3 of the gutter, the thickness of the foam blanket 2 of each panel 27 or 28 is slightly greater than that of the foam blanket in the gutter.

Thus, for a thickness of 56 mm for the gutter blanket, given as an example, one will match to such a gutter panels whose blanket is 60 mm thick. Consequently, because the panels are manufactured in their injection mold, one places polyurethane wedges of the desired thickness, i.e.

60 mm thick, in this example, between the interior covering 4 and the exterior covering 3.

The cap sections, shown in detail in figures 8 and 10, are produced according to the same sandwich design as the gutter and the panels, with the help of a third mold which will be suitable for all sections to be produced, given the absolute sameness of each element of the roof between its left cap 29 and its right cap 30.

The length and the transversal and longitudinal sections of this third mold are identical to the length and the sections of the caps to be produced.

The mold therefore has a length of 2.40 m.

As can be seen from the annexed drawings, the principle of joining the cap elements to the panels is the same as the one previously described between the panels and the gutter, i.e. it is carried out by longitudinal interlocking of a male part into a female part in complimentary form.

The interlocking is done from the top, which explains the V shaped notch 25 of the scales, which is designed to receive the complimentary projection 46 provided on the longitudinal edge of all cap sections, projections which can furthermore be chamfered in 47 to facilitate interlocking and adjustment.

In order for the two longitudinal projections 46 of each cap section to come out of the mold such as they should be, the two longitudinal sides bordering the bottom of the third mold form a fold towards the exterior under which, at the moment of injection and foaming, the polyurethane will expand and put the two projections 46 into their final form.

The longitudinal sides of each cap section are structurally identical to the inner longitudinal edge of panels 27, 28, i.e. that to border the V shaped notch 46 identical to notch 36, the following is planned: all along the longitudinal edge of the interior covering 4 a return 48 re-entrant towards the sandwich, a return inclined about 1350 in such a way as to be parallel to re-entrant return 45 formed on the longitudinal upper edge of the panel, all along the longitudinal edge of the exterior covering 3, a flexible clamp 45 is formed by a first fold 50 at 1350 towards the exterior, a second fold 51 at 1350 towards the interior, consequently parallel to the coverings, and of a last return 52, folded at 1350 towards the interior, a return 52 whose length is such that it rests elastically on the exterior covering of panel 27 or 28 and constitutes a first water stop over the whole length and in the upper part of each panel.

In other words, and as can be verified by comparing figures 5 and 8, return 48 and clamp 49 are identical to return 43 and clamp 37 respectively.

In the same way that a water-tight seal is integrated in space 41 situated in the upper part of the gutter under clamp 37, a joint 53, also watertight, is integrated under each clamp 49 in the space situated between returns 44 and 52 and runs the full length of the self-supporting element, thus creating, along the full length of element 1, a second water stop which is continuous through abutment of its various parts of 2.40 m each.

With the third water-stop formed by return 44 in the upper part of the panels, the watertightness becomes absolute all along the joining line between the panels and the cap elements which cover them.

The interior coverings 4 of the cap elements are of course coplanary with those of the panels so that they rest in the top part of the structure on the tips of the principal rafters as well as on a beam, at each summit of the element, as can be seen in figure 8.

On each cap section, the planed interior extremities, inclined at 450 of the interior covering are connected by a curvilinear part or better still, by an inclined partition 54 which extends horizontally underneath and on even level with the assembly devices 24.

The two rectilineal sides of the outer covering of the cap sections are themselves joined by a curvilineal partition 55 whose concavity is turned downwards, first to encourage the run off of rainwater at the top of the roof, second to give a harmonious shape to the roof as a whole. After the assembly of elements 1 the regularity and the symmetry of the corrugation give excellent results where industrial aestethics are concerned.

In addition to water-tightness guaranteed by the various returns 40, 34, 52, 44 and the joints 42 and 53, it is planned to provide total airtightness and for this purpose each re-entrant return 33-43-45-48 respectively, formed on an interior covering is equipped with an air-tight joint, 56-57-58 and 59 respectively.

The contacts between the joints opposite one another, 56-57 and 58-59 respectively, are created by compression at the time of the installation of the component parts in such a way that the air- and water-tightness is complete.

As we have shown previously, gutter 25 extends in a continuous line from one side of element 1 to the other or, as an option, extends in two extra-long sections united by a water-tight expansion joint, which, in any case, ensures continuity of the whole gutter component of the roof.

On the other hand, the panels and the caps are installed in 2.40 m long sections, under the gutter, overlapping with the basic structure so that it is necessary to plan additional watertightness devices on the right side of the various transversal connections which the various sections of the panels and caps respectively, form among themselves.

These water-tightness devices shown in detail in figures 6 and 11, are used simultaneously to interlock the panels on the one hand and the cap sections on the other hand.

The additional interlocking and sealing devices consist mainly of interior keys and exterior clips, which are designed identically both for the panels and the caps and have been designated as 60 and 61 for the keys used for the panels and the caps respectively. The clips have been designated as numbers 62 and 63 and are used for the panels and the caps respectively.

The keys are made in the shape of straight, square traverses which extend transversally and in a continuous line between the two longitudinal edges of the panels for some, between the two longitudinal edges of the cap sections for the others.

To avoid creating thermic points, these keys are made of wood or polyurethane foam or of any other thermoplastic material.

Keys 60 and 61 are imbedded transversally between the adjacent panels and the adjacent caps respectively, and this all along the two slopes of each element 1. For this purpose, one of the diagonals 64 of each key is placed in a vertical plane of the transversal connection between the two panels or two cap sections respectively.

In order to imbed the keys, it has then been planned to make V shape notches in the two transversal sides of each panel and of each cap section, as is shown in the cross-section of figure 6 in particular and in a dotted line in the details of figures 5 and 8.

These notches are symmetrical on the two transversal sides of the panel or cap part in which they are cut. Besides, the two slopes 65a of each notch are inclined 450 on the coverings in such a way as to constitute the ideal complimentary section of key 60.

Keeping in mind the preceding description, one can easily understand that the notches 65 of the panels and 66 of the cap sections are directly obtained at the time of manufacture, in the second and third molds respectively, by shaping the two transversal walls which border the bottom of the mold by two re-entrant folds whose two sides are also inclined in relation to the bottom and the top of the mold and who, together form a dihedral angle of 900.

Since the panel is planar, the notches 65 and their complimentary keys 60 extend rectilineally from one longitudinal side of the panel to the other.

On the other hand, due to the fact that a general shape of an overturned V has been given to each cap element 29 and 30, each notch 66 cut on a transversal section extends parallel to the interior covering 4 of the cap, i.e. according to two directions inclined 450 on the vertical and joined among themselves by a horizontal part parallel to wall 54.

The molds necessary for the manufacture of the three component parts of the insulating roof are now entirely explained concerning their length and the sections they must present longitudinally and transversally.

With these three molds, the injection of polyurethane foam takes place through all or only some of the four walls bordering the bottom of each mold. For this purpose, orifices of the number and diameter needed for a good injection are drilled in the walls.

On the other hand, the bottom and the top of the molds are not at all used to introduce the foam and this is, of course, to avoid drilling multiple holes in the exterior and interior covers which would damage the insulation, the watertightness and especially the mechanical resistance and the self-supporting property of the roofing element.

In order to allow an excellent hold of the panels among themselves, as well as of the girder sections among themselves, and to ensure at the same time a total tightness of the roof in all the transverse connections between two panels on the one hand, and two cap sections on the other hand, a flange 67 inclined 450 is provided on each transverse edge of interior covering 4. On each transverse edge of the exterior covering 3, an outwardly extending flange 68 is also provided. Its general direction is perpendicular to the plane of the coverings 3, the flange 68 presenting two folds which form a recess 69 that can serve as an anchor point for clip 62.

The flanges 67 and 68 extend in a continuous line on each transverse edge of each panel.

Identical flanges, of the same shape and with the same function are provided on all transverse edges of the cap sections. To the flanges 67 and 68 correspond flange 70-discontinued in the area where the inclined walls of the interior covering are joined to the horizontal wall 54and flange 71 whose recessed angle 72 serves to anchor clip 63.

At right angles with each transverse junction thus defined, the air- and water-tightness is ensured by joints placed at the extreme lower and upper parts of the junction.

Thus, an airtight joint 73, shaped in a V, is glued under key 60-61 and is compressed when adjusting the two flanges formed as opposites on the interior coverings of the two component parts, 67 for the panels and 70 for the caps respectively.

In the same way, an air-tight joint 74 is glued into the base of clips 62 or 63 respectively, presses against and is crushed by distortion around the free end formed by the exterior flanges, 68 for the panels and 71 for the caps respectively, as soon as the clamp snaps into place.

In their structure described above, i.e. at measurements of 2.40 m, aluminum coverings of 7/10 for the exterior and 4/10 for the interior and a foam of 60 kg/m3 density, each panel weighs approximately 23.5 kg for an insulating blanket of 60 mm thickness. This weight is largely the same no matter what the type of skylight, open 27 or blind 28.

With the same values as those given above, the weight of each cap section is 60 kg for a foam blanket of 64 mm thickness, a dimension measured in back of clamp 49, at a right angle of the part of the interior covering 4 which is coplanar with covering 4 of the panel.

In this zone e, it is quite clear that the cap must be a few millimeters above the constant thickness of the panel, 64 mm for example instead of 60 mm in as much as the flexibility of the longitudinal clamp 49 will be that much greater and that the contact of return 52 with the top of the panel will be sound and water-tight.

The gutter weighs about 6.6 kg per linear meter with an outer covering of 10/10 thickness and an insulating blanket of 56 mm.

A gutter of 10 to 1 2 m sufficient to cover one half of a self-supporting roof of conventional length thus would weigh between 65 and 80 kg.

It has therefore been properly verified that each of the three component parts of the insulating cover is sufficiently light-weight to be transported easily, or to be handled by a low-powered lifting device, be it at the factory or at the work site, or it can even be lifted by one man alone as far as the panels and caps are concerned.

The installation of the insulating cover is carried out in three stages, whether it is done immediately at the plant, on the basic structure also manufactured at the plant or whether it takes place only at the site where the roof is installed, overlapping from a structure also built on the spot or transported from a near-by workshop or a distant factory. These three stages are: 1 0) installing the gutter overlapping with the tie-chord and the base of the structure.

20) installing the windowed and/or blind scales overlapping with the panels of the basic structure, operations 1 0 and 20 taking place in the shop or on the work-site, and 30) installing the cap sections overlapping with the high lateral chords of the structures and the devices 24 used to assemble two adjacent elements 1 longitudinally, this third operation having to take place, of course, at the construction site only.

If the access from the construction site to the factory is easy, either by road or railway, the installation of the gutter in overlap with the basic structure should preferably take place at the factory. Thus the operations at the construction site would be limited to lifting elements 1 for assembly by their longitudinal sides 5 and 6 respectively and lastly the finishing of the insulating cover by caps 29 and 30.

On the other hand, if the access to the construction site demands a long maritime transport or shipment by air, it would clearly be more advantageous to manufacture the portable structure locally and to have the gutter, the panels and the cap sections shipped in containers and, to then successively assemble the prefabricated component parts to the basic structure at the construction site. It would even be preferable to do soon the top of the basic structure after lifting the various metallic structures and assembling them with devices 24.

The roofing of the structure always begins with the installation of the gutter which is centered above the tie-beam, bringing the two lateral parts of the gutter into contact with the base of the principal rafters 13 or 11 3. At each intersection created by the horizontal plane 81 of notch 32 and a principal rafter, the gutter is attached with a metallic clamp 76, the base 77 of which is welded to the principal rafter or is fixed sliding in the eye of a spare part of which one part is pivoting and the other part is welded to the principal rafter, with clamp 76 ending in claws 78 which grip the foam of the gutter just behind the air-tight joint 56 which is fitted on return 33.

It should be noted that clamps 76 attaching the gutter 25 to the basic structure do not create a thermic point which could damage the insulation since they do not go through the insulation cover.

Panels 27 or 28, with or without skylight 26, are then placed on the slopes of the basic structure, above the gutter, then progressively lowered along the slopes until projection 36 interlocks with the V shaped notch 32 and overlap from the top of the gutter and the slip joint 42 by longitudinal clamps 37.

The panels are then tightly joined to each other by the interior keys 60 and the exterior clips 62. A good adjustment of the keys between the two notches 65 which are opposite from each other is obtained by chamfering at 79 the longitudinal angles of the intersections of the traverses 60, as can be seen in the cross-section of figure 6 and in a dotted line in figures 5 and 8.

Keys 60 ensure an excellent placement of the panels in relation to each other and constitute a first element of fixation; besides, the keys limit deformation of the panels which could be due to heavy snow and finally they join the panels tightly by ensuring a good levelling on both slopes of the structure.

At the level of the tips of the web braces or the chords 11 and 12, the keys 60 are further held by fixation devices 80, each consisting, for example, of a tenon which is screwed into the key from underneath without going all the way through said key in order to avoid creating a thermic point.

The final joining of the panels to each other is ensured by flanges 68 which form the exterior coverings, in co-operation with clips 62 which, extending in a continuous line from one longitudinal side of each panel to the other, are elastic over the whole width of the panel, from top to bottom and ensure air- and water-tightness at the angle of their transversal junction.

A first advantage that stands out in a structure built in this manner is that the latter is perfectly symmetrical, balanced and covered with panels along the metallic structure in such a way that it makes no difference if one has to install a panel with a window or without one.

In this regard, if one refers to figures 1 and 2, one can see that the skylights have a trapezoidal shape the larger base of which is close to the upper longitudinal side of the panel and the smaller base is mostly located in the upper third of the panel counting from its interior longitudinal side.

In other words, skylight 26 is built in between two diagonals 13 or 11 3 which extend towards a common junction at the level of the central tiechord 9, which means that each skylight is likely to be built in a zone marked 82 in figures 2a, 2b and 2c.

In order to ensure a perfect insulation, the skylights will preferably have double glass which is installed with an air and water-tight seal all around the skylight. The skylight can either be stationary or can swing open either at their large or at their small base.

Conventionally, the panels 27 and skylights 26 will cover the northen slope of the roof and are placed, at the choice of the architect, at every step, that is to say in relation to all the spaces 82 either regularly every nth step, or else irregularly if one wishes to especially light up certain areas of the building to be covered.

Once the relative arrangement of the open and the blind panels is decided upon, one proceeds to the assembly along their longitudinal sides of the various self-supporting elements 1 which constitute the roof in question. For this purpose, it has been planned to weld, either in the factory or at the work site, identical parts made of molded steel, 83 left and 84 right respectively, to the outside of chords 11 and 12, every 2.40 m, at an angle with weld 1 8 by which the principal rafters are welded to the chords.

These parts 83 and 84, approximately 7 cm in length, each have the shape of a semi-cone, the base of which, 85 and 86 respectively form the upper face of the part, the point of which, 87 and 88 respectively, is turned downward, and whose lateral, semi-conic walls, 89 and 90 respectively, are put in the shape of a moulding to co-operate either with a cylindric chord as illustrated by unbroken lines in figures 7a and 8, or with a square chord as indicated by dotted lines in the same drawings.

The semi-conic parts, 83 and 84 respectively.

are welded to their respective chords, left 11 and right 12 by welds designated 91 and 92 respectively.

At the time of installation of the roofing elements 1 at the construction site, a part made of molded steel 93, consisting of a saddle 94 surmounted by a shaft 95 which ends in an eccentric threaded rod 96, is affixed to each part 84 of the beam 12 taken on the left element chosen as a reference example, by means of an eccentric cam disk 97 and a screw nut 98.

After the first element 1 of the has been installed, an element chosen on the left for the progression of the mounting of the roof, a second element is hoisted and laid at proximity to the right of the first element, parts 83 then being arranged opposite parts 84 on each of which part 93 is fixed.

The cam disk 97 occupies the position represented by 97a in figure 7b, a position which allows entirely free access to the groove located to the right of part 93.

The self-supporting element at the right to be joined to the self-supporting element to the left is lifted up a few centimeters, then lowered in order to automatically take its place in saddle 94 and ensure its positioning.

This sytem of conical interlocking permits a ridge course margin of 1 5 mm in the transverse sense and of 1 5 mm towards the front and towards the back in the longitudinal sense.

Once the second element is perfectly positioned in relation to the first left reference element, the eccentric cam disk 97 is turned by a quarter turn, as is illustrated by arrow 99, so that it occupies the position shown in unbroken lines in 97b of figure 7b, and screw nut 98 is then tightened in order to secure the two selfsupporting elements tightly together.

The obvious advantages of the assembly device 24 are manifold: a) The self-supporting elements of several dozen meters long are positioned vertically, transversely and longitudinally with ridge course margins of 15 mm.

b) The assembly of the seif-supporting elements is carried out exclusively at the top of the roof by simply manipulating screw nut 98 and the eccentric disk 97, which eliminates any work beneath the roof and therefore eliminates any risks of accidents as well. Nor is it necessary to erect scaffolding under the roof.

c) The assembly is rapid since it is sufficient to each device to simply tighten the screw nut and to simply turn the eccentric disk by 900. It is also economical since one bolting every 2.40 m is sufficient.

After the assembly, from left to right of the roof of all its elements 1 which constitute said roof, the assembly devices 24 which join in pairs the right side 12 of a first element to the left side 11 of a second adjacent element, are covered by cap sections 29-30, the installation of which is particularly easy due to their light weight (6 kg per 2.40 m) on the one hand, and the particular configuration of the projections 46, whose exterior flanks 100 are situated exactly vertically since the slopes of each element are inclined 450 and the projections 46 are V-shaped to form two orthogonal flanks 100 and 101.

Consequently, for the installation of the various cap sections, it suffices to put the projections 46 opposite the notches 35 which are free in the upper parts of the panels, and to gently lower the caps between the vertical planes of said notches 35 and, at the same time, each cap positions itself relative to the whole of the roof, i.e. interlocks in the upper part of the panels until it comes to rest on the interior side 4 on the lateral chords 11 and 12, at the same time covering the upper parts of the panels with longitudinal clamps 49, which, all at the same time compress the sealing joint 53 and with their last return 52 press on the exterior covering 3 of the panels.

In the longitudinal sense the cap sections 29 and 30 are joined end to end in such a way that all their transverse junction planes are each merged with a transverse junction plane between two panels 27 or 28.

In other words, the connection between two cap sections is defined at right angles with keys 60 and the attachment of clips 62 on the two returns 68, i.e. at right angles of joints 18 formed by the contact of two web braces on a lateral chord 11 or 12.

This arrangement of the cap meets with no difficulties, since each cap section weighs so little that its handling is very easy, and since each section is manufactured at a length of 2.40 mm, the same length as the panels and in keeping with the structure of the metallic components.

The cap sections, 29 and 30 respectively, are joined to each other by means of keys 61 shown in figure 8, of the same square cross-section as keys 60.

These keys 61, made of wood or polyurethane, extend transversely in a shape as close as possible to the one of a cap, i.e. the traverses 61 can be shaped into a circular arch, especially if the interior covering 4 of each cap section is also curved, or else it may be shaped in three sections, in a broken line, giving to keys 61 the shape of an inverted V, especially if the two borders of covering 4 connect according to a horizontal line 54.

Interposing keys 61, each imbedded between two adjoining cap sections, however, is not sufficient to guarantee a perfect hold of the cap elements on the roof. Indeed, the shape of projection 46 and its complimentary notch 35 which allow rapid and easy installation of the cap sections, is on the contrary not advantageous in regards to the hold of the cap elements through the other components of the roof.

Therefore, in order to fix the cap sections onto the roof, it is planned to associate with flanges 71, shown in Figure 8, clips 63 of the same shape and playing the same role as clips 62 described above with reference to contact between the panels.

Consequently, clips 63 are curved in a way to correspond to the curve of exterior covering 3 and flanges 71 of the cap sections and they extend transversely of the caps and over the lines of joining of adjacent caps.

In order to improve this contact even more, clips 63 extend outwardly from each side of flanges 71 over the panels of the two assembled elements 1, in such a way that the clips 63 snap over the clips 62. This additional inter-locking improves the hold of the cap sections on the roof even more.

In order for each clip 63 to interlock properly in the upper part of a clip 62, it is essential that the flanges 71 and 68 be precisely aligned and that there be practically no break between these returns.

The arrangement of the panels and the cap sections made with transverse connections at right angles to weld points 18 leads to a perfect alignment of flanges 71 and 68.

In their curve above exterior covering 3 the flanges 71 extend over clamp 49 in such a way that only the last bend 52 of the clamp extends beneath flange 71.

In these circumstances, in order that there will be practical continuity between the flanges 71 and 68, the latter are cut at 102 at their upper part at a length of about 2 mm more than the length of clamp 49. In this way, before the interlocking of clips 62 and 63, flanges 71 and 68 provide the desired continuity, as is clearly illustrated in figure 8.

The air- and water-tightness of the various cap sections is obtained by the same means used to ensure air and water-tightness between the panels in their transverse junction plane, meaning that a joint with a V-shaped section identical to joint 73, is interposed between the flanges 70 and key 61 and that a joint identical to joint 74 is compressed between the base of clip 63 and the free longitudinal side of the associated flanges 71.

Keeping in mind the assembly method described above in regards to the panels to each other on the one hand and the cap sections on the other hand, it is clear that the dismounting of the cap sections as well as that of the panels is especially simple and quick so that for maintenance purposes all operations such as: access to the gutter, changing of exterior air- and water-tight seals, replacement of panels and their fixation clips, replacement of cap sections and their fixation clips can all be carried out easily and therefore at greatly reduced cost, all the more since, for example, dismounting and replacing a panel can be carried out by removing only the cap which overlies it and without having to touch the adjacent cap sections or panels.

Bythe same token, opaque panels in the roof can easily be replaced by panels with windows should the natural lighting of the covered building be insufficient.

Another advantage is that the slopes of the insulating roof, inclined at 450, allow for the installation of solar captors on the south side, i.e.

as a general rule on the opposite side from the skylights.

These solar captors are constituted of panels 103 made of translucent molded polyester resin which are 2.40 m long so that they can easily be connected to clips 62 by means of the interlocking clamps 104 which like the clips 63 are pressed together over clips 62 under recess 69.

In this design, the panels of the south slope of the roof are painted with flat black paint to create a better absorbing element.

Solar panels 103 are fixed at some centimeters above the panels in order to better retain the warm air.

Thus solar captors are constructed inside of which air is warmed by a hothouse effect.

In this hothouse, the air is introduced through a duct 105 and heated air is aspirated from the upper part through opening 106 at right angles of which opens an elementary duct 107 which is connected to a general pipe which extends longitudinally under the assembly devices 24 and in which the hot air that has been recuperated from the different elementary ducts 107 and which will be distributed to the interior of the building, circulates.

The hot air collected through the various general ducts will then be used to either heat the ambient air of the building, or for heating through the floor, or else to heat the water coils for hot water in the washrooms or to produce cold for the airconditioning of the building.

The inlet 105 for the intake of cold air and the opening for the outflow of hot air are arranged diagonally and at a distance of three to five panels of 2.40 m from each other. Consequently, every three to five modules a vertical separator is interposed between clip 62 and the container to right angles to the fastener clamp 104.

The solar collectors of the type described above can be constructed at the plant or may even without any major modifications be installed at the construction site itself, during or after the installation of elements 1.

In fact, in order to equip a building with solar captors, the only modification needed is to puncture a panel every three to five modules so as to make a passage for the elementary ducts 107 for the aspiration of hot air from the upper part of the collectors.

In order to recover rainwater, the selfsupporting elements 1 are all installed at the work site with the same 2% pitch obtained by the relative heights of the walls 1 9 and 20 of the supporting structure in concrete or metal.

The rainwater collected in the bottom of each gutter 25 is then recovered in a common guttering 109 which extends transversely along the whole facade of the building to be covered.

To ensure perfect water-tightness at the end of the gutter, in the area where the rainwater is recovered by guttering 109, it is planned to weld a part 110 of triangular shape of which the upper side 111 is rounded to fit into the curved side at the bottom of the gutter and into the center of the web braces 11 3.

A flange 112 provided on the upper side of 111 of metal sheet 110, extends towards the exterior of the building. This flange has a double role: provide water-tightness under the foam blanket of the gutter and serve as support for gutting 109.

Each of the longitudinal flanges 112 is pierced by two holes for the passage of threaded rods 11 5, thanks to which, and with the help of screw nuts 116 fastened under the rims 11 7 of the guttering, it is possible to give the latter the desired slope for the proper outflow of the collected water.

In order to avoid backing up of the water at the end of each gutter 25, it is been planned to notch the latter with notch 11 8 of shape as shown in Figure 1. the sides from the exterior covering to the interior covering.

The slant of flanges 112 which is similar to the slope of notch 1 8 ensures in any case the watertightness of the end of blanket 2 of the gutter on either side of 11 8.

It is also planned to protect the two component parts of the insulating cover on its two end sections 7 and 8 by means of fronton elements, which at the same time ensure the aesthetic aspect of the end of the roof.

By referring to figures 1,4 and 9 one can see that the mounting of these elements is implemented by sliding along the returns at the frontal end of the gutter and the adjacent panel.

For aesthetic reasons and also to protect the tympanum of the facade from bad weather, a weather board may be placed at the end of each slope of each self-supporting element 1. This weather board 119 will follow the design of the panels and its transverse side will preferably be chamfered with a slope inclined towards the back, from top to bottom, the weather board 11 9 jutting out in relation to the end diagonal 21 by about 60 cm at its upper part and about 30 cm at its lower part.

Each end panel consequently will have a first frontal flange 120 which extends towards the top of the exterior covering and a second frontal flange 121 which extends towards the inner covering.

By their inclination, these flanges 120 and 121 provide the inclination desired for the weather board.

For the same purpose, gutter 25 is extended downwards, through its interior covering by a first frontal flange 122 which provides the inclination desired for the weather board and through its exterior covering of a second frontal flange 123 which jutts out slightly towards the front of the flanges 120, 121 and 122 (figure 9). Flanges 120-121 and 122 have an height of about 30 mm while the flange 123 has a lesser height of about 20 mm.

The fronton elements, symmetrical with respect to each corrugation of the roof, are Ushaped, made of plastic or extruded aluminum.

Two variations of a transverse sections are illustrated in figure 9.

The centre-rib of each fronton element section 1 25 has a projection 126 opposite flange 1 23 and turned towards the front of the roof, space 127 thus defined between the fronton element and return 123, being able to compensate for movement of the exterior covering of gutter 25, as is shown by arrow 128 in the drawing.

Section 125 has a longitudinal groove in each of its two ends 129 and 130, upper and lower respectively, which are parallel to portion 124 and which grooves enable the ends to receive the flanges 120 in the upper groove, 121 and 122 in the lower groove respectively.

The installation of fronton elements 125 is implemented by sliding, starting at the upper part of the roof, as illustrated by arrow 133.

In this sliding operation, groove 131 cooperates with flange 1 20 formed by the exterior covering of the panel upwardly and groove 132 co-operates with flange 121 formed by the interior covering of the panel downwardly wards, and finally co-operates with flange 1 22 formed by the gutter, the flange 122 agreeing very exactly to flange 121 of the panel.

The fronton element 125 may have any shape the architect or the user desires. Thus, in the variation illustrated in broken lines in figure 9 as an example, the centre-rib 124 clearly extends under flanges 121 and 122 and its lowered end 1 30 thus provides coverage of the ends of the roof.

In this variation, centre rib 124 has a clamp 1 34 on its inside, which set at right angles with the extremities of returns 121 and 122 assumes the role of a slide, just like groove 132 during the installation by sliding of element 125.

The frontal extremities of the building between the supporting structure 19, 20 and each corrugation of the roof thus constructed are concealed by the tympanum 135 as illustrated by broken lines in figure 4 and crossed line in figure 1. The tympana are made from insulating sandwich panels or by double windows.

Whether opaque or windowed, the tympana are stationary or, as an option, can be opened.

If the latter is the case, the two halfs of each tympanum are preferably installed in such a way as to swing open towards the inside of the building around a rotational vertical shaft around with axis 23.

As an option, a subceiling can be installed under the metallic supporting structure, preferably suspended by the members of said structure.

This sub-ceiling, constructed of modules of 2.40 m length and made of fibre-board, of stainless steel, of galvanized steel or any other material resisting to fire for at least thirty minutes, has three functions: Aesthetic, by hiding the metallic sections of the structure, Security, by protecting the metallic structure from fire for at least thirty minutes, Improvement of the insulation by the air space created between the interior covering of the sandwich elements and the upper side of subceiling.

The invention is, of course, not limited to the applications nor to the methods of implemention which have been described. Different variations could be designed while still remaining within the framework of this invention.

Claims (12)

Claims

1. A self-supporting extra-long truss element for the construction of a roof of a building, the roof being formed by joining together several of such elements positioned side by side parallel to each other, the element being of composite construction comprising an elongate support structure made of metallic sections extending continuously from side to side and from end to end of the element and a cladding provided on the support structure, the cladding comprising replaceable panels at least some of which have an exterior, corrosion-resistant cover and an interior cover which is similar in configuration to the outer cover and which is positioned parallel to and beneath the latter, and an insulating filling of a foam of a material possessing good fire-resistant and adhesive properties between the two covers.

2. An element according to Claim 1 in which the said insulating filling is provided by injection and subsequent polymerization of the foam.

3. An element according to Claim 1 or Claim 2, the elongate support structure comprising three tubular parallel spaced-apart members which extend longitudinally and continuously between the two ends of the element, one said tubular member element being disposed centrally equidistant from the two sides of the element and the other two said tubular members being disposed each along a respective one of the two longitudinal sides of the element, and braces located on either side of the central tubular member extending between it and the other tubular members, and disposed symmetrically with respect to a longitudinal plane including the said central tubular member.

4. An element according to Claim 3, wherein the braces each extend either from a said side member to the said central member or extend continuously from one side member to the other and which are welded to the central member in the middle.

5. An element according to Claim 3 or Claim 4, wherein all of the braces are inclined at substantially the same angle to a plane normal to the longitudinal direction of the element.

6. An element according to Claim 5, wherein the braces are arranged in zig-zag configuration and incline alternately towards one end and the other of the element, the points of connection of each brace to the central member and to one or both side members being at the points of connection of adjacent braces and the central and the side members respectively.

7. An element according to any one of Claims 3 to 6, which is in transverse cross-section in the shape of a V, symmetrical about the said longitudinal plane, which planes is vertical and includes the longitudinal axis of the central member, the central member being welded to the braces in an area where the latter are rounded and provide an upwardly open concavity to receive a gutter, the braces inclining outwardly at either side of the position for the gutter at approximately 450 to the horizontal, the two side members providing top elongate side edges along the element.

8. An element according to Claim 7, wherein the said cladding further comprises a central gutter resting on the central member and on the bases of the inclined braces, the said panels being supported by and secured to the braces and joined to the gutter in such a way as to ensure airand water-tightness; and cap sections overlapping a top side edge of the element and a top side edge of a second adjacent element positioned against the first element, the cap sections resting on the tips of the braces and on a side member of both the first and second elements, the cap sections being attached to the two elements to ensure air- and water-tightness.

9. An element according to claim 8, wherein the gutter extends continuously or in sections of about ten meters long from one end of the element to the other, the panels and the cap sections being of shorter length, some of the panels being solid and opaque and others including a skylight for providing natural lighting for the building.

10. An elements according to claim 8 or claim 9, wherein the panels are tightly joined to one another by means of interior keys and exterior clips, and the cap sections are tightly joined to each other also by means of interior keys and exterior clips.

11. An element according to any one of claims 8 to 10 wherein the gutter is secured to the braces and the panels interlock in the gutter and are secured to the braces by means of clips.

12. An element according to claim 11, wherein the securement of the gutter and the panels to the braces is by means of clamps which do not puncture the insulated foam positioned between the exterior and the interior covers.

1 3. A self-supporting extra-long truss element substantially as herein described with reference to and as illustrated in the accompanying drawings.