EP0530101A1 - Watertight roof for buildings and method of laying the same - Google Patents

Abstract

After having laid the ribbed steel sheets (2) onto the purlins (1) of the frame, and placed the layer of insulation (3) on top, a flexible tape or a row of flexible small plates (4) for the connection of covering are laid on top of this layer of insulation, in line with each purlin, and then washers or rigid iron strips (5) are placed on top. Self-tapping screws or the like (6) are then inserted through the washers or iron strips; after having passed through the tape or the flexible small plates, the insulating layer and the ribbed steel sheet, these screws are screwed into the purlins (1). Finally, the watertight covering is fitted while being adhesively bonded or welded on the tapes or the flexible small plates (4). Application to the roofing of industrial buildings. <IMAGE>

Description

The present invention relates to a waterproof building cover, in particular for an industrial building, of the type described in the preamble of claims 1 and 4.

• on fixe les tôles d'acier nervuré sur les éléments (généralement les pannes) de la charpente, au droit des creux d'onde;
• on fixe les plaques isolantes sur les tôles d'acier nervuré par des vis ou analogues, c'est-à-dire des vis, des rivets ou des goujons, dont la tête s'appuie sur une rondelle rigide. Ces vis se vissent dans les tôles d'acier nervuré;
• enfin, le revêtement d'étanchéité est rendu solidaire des plaques d'isolation par collage ou par soudage à l'aide d'une source chaude, le plus souvent par un chalumeau à flamme ou à air, sur toute la surface des panneaux isolants et éventuellement au droit des rondelles des vis. En variante, le revêtement peut être fixé par des vis de la même manière que les plaques isolantes.

The classic technique for installing covers of this type described in DTU 43.3 (French standards) is as follows:

• the ribbed steel sheets are fixed on the elements (generally the purlins) of the frame, in line with the troughs;
• the insulating plates are fixed to the ribbed steel sheets by screws or the like, that is to say screws, rivets or studs, the head of which rests on a rigid washer. These screws are screwed into ribbed steel sheets;
• finally, the waterproofing coating is made integral with the insulation plates by bonding or by welding using a hot source, most often by a flame or air torch, over the entire surface of the insulating panels and possibly in line with the screw washers. Alternatively, the covering can be fixed by screws in the same way as the insulating plates.

The wind creates significant compression and depression forces, in places, on the roof (swirls, mask effect behind a wall or an emergence of the roof). The forces are exerted on the exterior surface, therefore on the waterproofing coating, which ultimately stresses the load-bearing element and the structure of the building.

In order to resist the forces of depression created by the wind, the French standards defined within the framework of the D.T.U. 43.3 and uses provide for a minimum of five fastenings per m² of roof, assuming that a fastening screw resists about 900N tearing.

The rupture is located at the plane of bonding of the sealing coating on the washer, or by unbuttoning the fixing head through the washer, or by tearing off the fixing through the ribbed sheet steel. The breaking values are relatively homogeneous, of the order of 900 to 1300 N.

In this classic technique, the large number of fasteners which is necessary makes the implementation long and expensive. In addition, all the fasteners appear on the underside of the ribbed steel sheets, which is awkward from an aesthetic point of view.

The object of the invention is to provide a cover of the same type which is much faster and economical to implement and which practically does not allow the appearance of screws or the like on the underside.

To this end, the subject of the invention is, according to a first embodiment, a waterproof cover of the aforementioned type, characterized by the characterizing part of claim 1.

Other features are described in claims 2 and 3.

According to another embodiment, the cover according to the invention, of the aforementioned type, is characterized by the characterizing part of claim 4.

In this case, preferably, each row of fixing members comprises at least two of these members per raised area.

Other features, which can be applied to either of the above two embodiments, are described in claims 6 to 10.

The invention also relates to a method of laying on parallel elements of the frame of a building, a cover comprising ribbed steel sheets, an insulating layer, in particular formed of plates adjacent, arranged on these sheets, and a sealing coating covering the insulating layer.

In the case of a cover according to the first embodiment described above, this method is characterized by the characterizing part of claim 11.

In the case of a covering according to the second embodiment described above, the laying method according to the invention is characterized by the characterizing part of claim 12.

• la Figure 1 est une vue en perspective d'une couverture étanche conforme à l'invention, en cours de pose, suivant deux variantes de mise en oeuvre;
• les Figures 2 et 3 sont des vues en coupe prises le long d'une panne de la charpente, respectivement suivant les lignes II-II et III-III de la Figure 1, de la couverture complète;
• la Figure 4 est une vue en plan, avec arrachement, de l'objet de la Figure 2;
• la Figure 5 est une vue à plus grande échelle prise en coupe suivant la ligne V-V de la Figure 2 ou de la Figure 3;
• la Figure 6 est une vue analogue à la Figure 2 d'un autre mode de réalisation de la couverture selon l'invention;
• la Figure 7 est une vue prise en coupe suivant la ligne VII-VII de la Figure 6;
• la Figure 8 est une vue analogue à la Figure 5 d'un autre mode de réalisation de la couverture selon l'invention, munie d'une surtoiture; et
• la Figure 9 est une vue en coupe longitudinale d'un accessoire utilisable dans le mode de réalisation de la Figure 8.

Examples of embodiments of the invention will now be described with reference to the appended drawings, in which:

• Figure 1 is a perspective view of a waterproof cover according to the invention, during installation, according to two alternative embodiments;
• Figures 2 and 3 are sectional views taken along a breakdown of the frame, respectively along lines II-II and III-III of Figure 1, of the complete cover;
• Figure 4 is a plan view, with parts broken away, of the object of Figure 2;
• Figure 5 is an enlarged view taken in section along the line VV of Figure 2 or Figure 3;
• Figure 6 is a view similar to Figure 2 of another embodiment of the cover according to the invention;
• Figure 7 is a sectional view taken along line VII-VII of Figure 6;
• Figure 8 is a view similar to Figure 5 of another embodiment of the cover according to the invention, provided with a roofing; and
• Figure 9 is a longitudinal sectional view of an accessory usable in the mode of realization of Figure 8.

The building cover shown without its waterproof coating in Figure 1 is placed on a series of purlins of parallel frames 1 made of I-irons with vertical core. It is made up of ribbed steel sheets 2 whose waves are perpendicular to the purlins, thermally insulating plates 3 rectangular, more or less compressible, arranged contiguously, members 4 for covering the covering, support members 5, and fixing screws 6.

The ribbed steel sheets 2 define raised areas 7 of relatively large width and much narrower wave hollows 8 with flanks 9 which are strongly inclined and at the bottom 10 parallel to the areas 7.

The connecting members 4 are relatively flexible and have, at least on their upper surface, a material compatible with that of the sealing coating with a view to bonding or welding it. It may be a strip, continuous or consisting of successive sections, or plates, as illustrated respectively in the right part and in the left part of FIG. 1, of thin metal coated with an appropriate material or made of the same material as the waterproofing coating and provided with a tear and tensile resistant frame. The width of this strip, or the size of the plates, can be of the order of 0.15 to 0.20 m.

The support members 5 are rigid members, in particular made of sheet steel at least 1 mm thick, protected against corrosion, for example by galvanization. It may be a succession of strips of elongated shape or washers, as illustrated respectively in the right part and in the left part of Figure 1. The diameter of the washers can be of the order of 60 mm and the strip width of the order of 40 mm. These dimensions are in any case significantly less than the width of the flexible strip 4 or the dimension of the flexible plates 4. - As can be seen in Figures 2, 3 and 5, each washer may have a deep-drawn bowl 11 having little near the same height as the heads 12 of the screws 6, and each strip can have two longitudinal ribs 11 having a height of the same order.

The screws 6 have a length greater than the sum of the thickness of the wings 13 of the purlins, the height of the ribbed steel sheets 2 and the thickness of the plates 3. They have, from their head 12, a smooth part 14, the length of which is greater than the sum of the thicknesses of the plates 3 and of the sheet metal 2, then a threaded part 15 and a self-tapping or self-tapping-tapping point 16. Alternatively, the screws 6 could be threaded over their entire height.

• (a) On met en place sur les pannes les tôles d'acier nervuré 2 et, si nécessaire, on assure leur fixation provisoire sur ces pannes au moyen d'organes de fixation 17 (Figures 2 et 3) disposés dans certains creux d'onde 8.
• (b) On pose un certain nombre de plaques isolantes 3.
• (c) Au droit d'une panne 1 chevauchée par ces plaques, on dispose une rangée de plaquettes 4 ou une bande souple 4. Si on utilise des plaquettes, on les pose à l'aplomb de plages 7 des tôles 2, par exemple à raison d'une toutes les quatre plages ou toutes les deux plages.
• (d) Sur chaque plaquette on pose une rondelle 5, ou bien sur chaque bande 4 on pose des feuillards ou une rangée de rondelles 5 situées comme indiqué ci-dessus pour les plaquettes 4.
• (e) On visse une vis 6 dans chaque rondelle 5 ou bien à des emplacements correspondants des feuillards 5. Ces vis traversent les plaquettes ou la bande 4, la plaque 3 et les plages 7 concernées, puis se vissent dans la branche supérieure de la panne, avec leur tête 12 en appui sur une rondelle ou un feuillard 5. Dans le cas d'utilisation de feuillards 5, ceux-ci peuvent être prépercés pour faciliter l'introduction des vis 6.
• (f) On répète les opérations (b) à (e) pour toutes les pannes chevauchées par les plaques 3 déjà en place, puis pour les autres parties de la couverture.
• (g) Enfin, on déroule le revêtement d'étanchéité 18, constitué d'une matière synthétique souple tel que le PVC ou d'un produit bitumineux, tout en le fixant par collage ou soudage sur les plaquettes ou la bande 4 et éventuellement sur les rondelles ou les feuillards 5. Bien entendu, les lés du revêtement d'étanchéité sont collés ou soudés entre eux dans leurs zones de recouvrement.

The installation of this cover is carried out as follows.

• (a) The ribbed steel sheets 2 are placed on the purlins and, if necessary, their temporary fixing is ensured on these purlins by means of fastening members 17 (Figures 2 and 3) arranged in certain recesses wave 8.
• (b) A number of insulating plates 3 are placed.
• (c) In line with a breakdown 1 overlapped by these plates, there is a row of plates 4 or a flexible strip 4. If plates are used, they are placed directly above the areas 7 of the sheets 2, for example at the rate of one every four tracks or every two tracks.
• (d) On each wafer we place a washer 5, or on each strip 4 we put strips or a row of washers 5 located as indicated above for the wafers 4.
• (e) A screw 6 is screwed into each washer 5 or else to corresponding locations of the strips 5. These screws pass through the plates or the strip 4, the plate 3 and the pads 7 concerned, then are screwed into the upper branch of the purlin, with their head 12 resting on a washer or a strip 5. In the case of the use of strips 5, these can be pre-drilled to facilitate the introduction of the screws 6.
• (f) Repeat operations (b) to (e) for all the failures overlapped by the plates 3 already in place, then for the other parts of the cover.
• (g) Finally, the sealing coating 18, consisting of a flexible synthetic material such as PVC or of a bituminous product, is unwound, while fixing it by bonding or welding on the plates or the strip 4 and optionally on the washers or the strips 5. Of course, the strips of the sealing coating are glued or welded together in their overlap zones.

An easy-to-install waterproof cover is thus obtained in which the fixing screws are practically invisible. In addition, the wind-off forces exerted on the waterproofing coating are directly transmitted to the purlins 1 via the fixing screws 6, the coating not being fixed to the insulating plates 3 or to the ribbed steel sheets 2.

• d'une part, que la longueur des vis 6 n'est pas critique, de sorte que les mêmes vis peuvent être utilisées avec une grande variété de tôles d'acier nervuré et d'épaisseurs de plaques isolantes;
• d'autre part, que les efforts de compression (dus au vent et aux charges d'exploitation telles que eau, neige, circulation d'entretien...) sont exercés sur le revêtement d'étanchéité puis sont transmis aux plaques d'isolation thermique 3, puis sont transmis aux tôles d'acier nervuré 2, sans nécessiter de fixation de celles-ci, puis aux pannes 1. Les tôles d'acier nervuré sont donc calculées en fonction de ces seuls efforts de compression et de l'écartement entre les pannes 1, et non en fonction des charges de dépression dus au vent.

It should also be noted:

• on the one hand, that the length of the screws 6 is not critical, so that the same screws can be used with a wide variety of ribbed steel sheets and thicknesses of insulating plates;
• on the other hand, that the compression forces (due to wind and operating loads such as water, snow, maintenance traffic, etc.) are exerted on the waterproofing coating, then they are transmitted to the thermal insulation plates 3, then are transmitted to the ribbed steel sheets 2, without requiring fixing thereof, then to the purlins 1. The ribbed steel sheets are therefore calculated as a function of these compression forces alone and of the spacing between the purlins 1, and not as a function of the vacuum loads due to the wind.

The tensile strength of the screws 6 depends on the spacing of the purlins, the vacuum forces due to the wind (and therefore on the geographic region) and on the spacing between the screws above the same purlin. For example, in France, for distances between purlins of 3 m and between fixings on the same purlin of about 0.50 m (every two waves of the sheets 2), the tensile strength of the screws 6 will not be less at 3000 N and will preferably be 5000 N with a safety factor of the order of 1.5.

In general, the components 4 to 6 of the cover are dimensioned so as to obtain everywhere an approximate homogeneity of the tensile and / or tear performances with respect to the tearing forces perpendicular to the roof or parallel to this: tensile strength between the screws 6 and the purlins, tensile strength between the heads 12 of the screws 6 and the washers or strips 5, tensile strength, perpendicular to the roof, between the plates or the strip 4 and the washers or the strips 5, tear resistance between the plates or the strips 4 and the rod of the screws 6, with respect to forces parallel to the roof, resistance of the bonding or welding between the coating d '' sealing and plates or bands 4 and / or washers or strips 5.

The bowl or ribs 11 of the supporting members 5 reduce the risk of perforation of the coating sealing by the heads of the screws 6.

As shown in phantom in Figure 5, the screws 6 can pass through a metal tubular spacer 19 interposed between the upper face of the ribbed steel sheet 2 and the assembly 4-5. This makes it possible to avoid, under the effect of the maintenance circulation, the perforation of the sealing coating by the fixing heads 12, especially with flexible and compressible thermal insulation plates 3.

The embodiment of Figures 6 and 7 differs from the previous one in that the tearing forces are transmitted to the purlins 1 indirectly, by means of ribbed steel sheets. For this, the sheets 2, which are made more rigidly than previously, are firmly fixed to the purlins, by means of fasteners 17 provided in each wave trough, and the number of screws 6 is increased, for example, as shown , two per track 7. Such an arrangement can be interesting in regions with little wind.

The embodiment of FIG. 8 differs from that of FIGS. 1 to 5 in two aspects: on the one hand, the washers 5 are flat and welded to the rod of the screws 6. On the other hand, these screws comprise, au- above the washer 5, an extension 20 which passes through the sealing coating and which projects slightly above it. This extension is threaded and receives by screwing the tapped lower bushing 21 of a support 22. The upper part 23 of this support is threaded, and on it is screwed, at an adjustable height, a plate 24. A rail 25 is fixed on all of the plates 24 of the same row, and an over-roof 26 having essentially an esthetic, non-watertight purpose, is fixed on the beams 25.

In this embodiment, to facilitate the installation of the waterproofing covering, one can start by screw a temporary cap 26 with a pointed head as shown in FIG. 9 onto the extensions 20. These plugs easily perforate the coating 18, and can then be removed to allow the supports 22 to be screwed.

In the embodiment of FIG. 8, the sealing of the covering is obtained by gluing or welding the covering 18 on the elements 4 and 5, all around the extension 20 of each screw 6.

As a variant, in each of the embodiments described above, the support members 5 can be integral with the connecting members 4 or even integral with them, in particular when the members 4 are made of coated metal.

Claims (12)

1 - Watertight building cover, especially for an industrial building, of the type comprising ribbed steel sheets (2) placed on parallel elements (1) of the building frame with the waves of these sheets extending perpendicular to these elements , an insulating layer (3), in particular formed of adjacent plates, disposed on these sheets, a sealing coating (18) covering the insulating layer, and connecting means (4 to 6) for holding the three components together (2 , 3, 18) of the cover and fix them to the frame, characterized in that said connecting means comprise, in line with each of said frame elements (1) and only at these locations: - coating connecting members (4) placed on the insulating layer (3) and comprising a row of flexible plates (4) or a flexible strip (4); - rigid support members (5) placed on the connecting members (4) and comprising a row of washers or a succession of strips; and - a row of fixing members (6), each fixing member passing through a support member (5), a connecting member (4), the insulating layer (3) and a ribbed sheet steel (2) and fixing in the corresponding frame element (1), each fixing member (6) having a head (12) which bears on the support member (5); and in that the sealing coating (18) is fixed only on the connecting members (4) and possibly on the support members (5). 2 - Cover according to claim 1, characterized in that each fixing member (6) crosses a raised area (7) of the ribbed sheet steel (2). 3 - Cover according to claim 1 or 2, characterized in that it comprises members (17) for temporarily fixing the ribbed steel sheets (2) to the structural members (1), these members passing in particular through hollow waves (8) of this sheet . 4 - Watertight building cover, in particular for industrial buildings, of the type comprising ribbed steel sheets (2) placed on parallel elements (1) of the building frame with the waves of these sheets extending perpendicular to these elements , an insulating layer (3), in particular formed of adjacent plates, disposed on these sheets, a sealing coating (18) covering the insulating layer, and connecting means (4 to 6) for holding the three components together (2 , 3, 18) of the cover and fix them to the frame, characterized in that said connecting means comprise, in line with each of said frame elements (1) and only at these locations: - A row of screws or the like (17) fixing the ribbed steel sheets (2) to the structural element (1), these screws or the like passing in particular through each trough (8) of these sheets; - coating connecting members (4) placed on the insulating layer (3) and comprising a row of flexible plates (4) or a flexible strip (4); - rigid support members (5) placed on the connecting members (4) and comprising a row of washers or a succession of strips; - a row of fixing members (6), each fixing member passing through a support member (5), a connecting member (4) and the insulating layer (3) and fixing on a raised surface (7) of a ribbed sheet steel, each fixing member (6) having a head (12) which bears on the support member (5); and in that the sealing coating (18) is fixed only on the connecting members (4) and possibly on the support members (5). 5 - Cover according to claim 4, characterized in that each row of fixing members (6) comprises at least two of these members per raised area (7). 6 - Cover according to any one of claims 1 to 5, characterized in that each fixing member (6) is a self-tapping or self-tapping screw. 7 - Cover according to any one of claims 1 to 6, characterized in that the support members (5) have a raised area (11) around or on either side of each head (12) of organ fixing (6). 8 - Cover according to any one of claims 1 to 7, characterized in that a rigid sleeve (19) surrounds each fixing member (6) and forms a spacer between the support members (5) and the sheets ribbed steel (2). 9 - Cover according to any one of claims 1 to 8, characterized in that each fixing member (6) has upward an extension (20) on which is fixed a support (22) of over-roofing (26). 10 - Cover according to claim 9, characterized in that it comprises temporary plugs (26) with pointed heads adapted to be mounted on said extensions (20) before the installation of the covering (18). 11 - Method for laying on parallel elements (1) of the frame of a building, a cover comprising ribbed steel sheets (2), an insulating layer (3), in particular formed of adjacent plates, placed on these sheets, and a sealing coating (18) covering the insulating layer, characterized by the following sequence of steps: (a) we place ribbed steel sheets (2) on the structural elements (1) with the waves of these sheets extending perpendicular to these elements, and, if necessary, these sheets are fixed on the structural elements , in particular by means of screws or the like (17) which pass through troughs (8); (b) part of the insulating layer (3) is placed on the ribbed steel sheets (2); (c) on this layer, a row of flexible plates (4) or a flexible strip (4), intended for the connection, is placed, in line with each structural element (1) that it covers and only at these locations coating; (d) a row of rigid washers or a succession of rigid support strips (5) is placed on the plates or the strip (4); (e) fixing members (6) are introduced through the washers or the strips (5) which, after passing through the plates or the strip (4) then the insulating layer (3), pass through the ribbed steel sheets then are fixed in the frame element (1); (f) repeating operations (b) to (e) over the entire extent of the cover; and (g) the sealing coating (18) is placed on the assembly thus produced, while fixing it, in particular by gluing or welding, on the flexible plates or strip (4) and possibly on the washers or the strips ( 5). 12 - Method for laying on parallel elements (1) of the frame of a building, a cover comprising ribbed steel sheets (2), an insulating layer (3), in particular formed of adjacent plates, placed on these sheets, and a sealing coating (18) covering the insulating layer, characterized by the following sequence of steps: (a) we place ribbed steel sheets (2) on the structural members (1) with the waves of these sheets extending perpendicular to these elements, and these sheets are fixed on the structural members, in particular by means screws or the like (17) which pass through troughs (8) therein; (b) part of the insulating layer (3) is placed on these ribbed steel sheets (2); (c) on this layer, a row of flexible plates (4) is placed, in line with each raised element (7), in line with each frame element (1) which it covers and only at these locations ribbed steel sheets, or a flexible strip (4), intended for the connection of the covering; (d) a row of rigid washers (5) is placed on the plates or the strip (4) each located at the level of an elevated surface (7) of ribbed steel sheets, or a succession of rigid support strips (5); (e) fixing members (6) are introduced through the washers or the strips (5) which, after passing through the plates or the strip (4) then the insulating layer (3), are fixed in said raised areas; (f) repeating operations (b) to (e) over the entire extent of the cover; and (g) the sealing coating (18) is placed on the assembly thus produced, while fixing it, in particular by gluing or welding, on the flexible plates or strip (4) and possibly on the washers or the strips ( 5).

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