Roof construction and means for fastening a sealing layer.
The present invention relates to a roof construction comprising a supporting substructure, an insulating layer, a sealing layer, and a device for fixing the sealing layer and the insulating layer to the substructure, said device including a plurality of attachment members, each including an anchoring element that is anchored to the substructure.
The invention also relates to a device for fixing a sealing layer and an insulating layer to a supporting substructure of a roof construction, said device including a plurality of attachment members, each including an anchoring element that is anchored to the substructure .
When externally insulating a roof construction, the insulating layer must be fixed to the supporting substructure, which can consist of concrete, lightweight concrete, wood, or sheet-metal. The fixing is accomplished with the aid of different types of attachment members, including anchoring elements, for instance nails or screws. The sealing layer is built up of lengths of material of a specific width, which are adapted, with overlapping, to the c-c distance between consecutive rows of bracing legs in the components that make up the substructure. It is thus important that consecutive lengths of material overlap where said bracing legs occur. Consequently, one and the same c-c distance between bracing legs and material of a specific width must be used throughout the entire substructure to place the overlaps in specific positions within the locality of the bracing legs. This can result in unnecessarily large overlaps or insufficient overlaps leaving a risk of pervious joints occurring.
The object of the present invention is to eliminate the above-mentioned disadvantages and to provide a device in a roof construction to enable a wider sheet, such as 2 , . or 6 metres wide, instead of a plurality of lengths of material, to be used and the same to be placed over the insulating layer to cover it and previously anchored attachment members, whereupon the sheet-shaped covering layer can be fastened to the fixing members without regard to the location of joints, if any, in the sheet.
In accordance with the invention, the roof construction, as well as the device, is characterized in that the attachment member comprises
- a sleeve, having a through-running hole that is tapered within the anterior portion of the sleeve to form an internal seat for co-operating with a stop head on the anchoring element, said sleeve being shorter than the thickness of the insulating layer and is arranged to be telescopically displaceable in relation to the anchoring element,
- a rigid joining element supported by the sleeve at its posterior end and having a plane joining surface, perpendicular to the longitudinal axis of the sleeve, and
- a layer of an adhesive, arranged on said joining surface to adhere to the sealing layer and to form a permanent joint between the sealing layer and the joining element .
The invention is further described in the following with reference to the drawings.
Figure 1 is an exploded view of a roof construction in accordance with the invention with its various fundamental parts.
Figure 2 is a cross-section of part of the finished roof construction .
With reference to Figure 1, this shows, in an exploded view, fundamental parts of a roof construction including a substructure 1, an insulating layer 2, laid out on the substructure 1, and a thin sealing layer 3 of a plastic material, preferably polyvinyl chloride. The substructure 1 can consist of concrete, lightweight concrete, wood, or sheet-metal. The insulating layer 2 consists of a material having a certain load-bearing capacity so that it can support a person without being permanently compressed at the location of the load. A suitable material for the insulating layer 2 is of a cellular-plastic type. The sealing layer 3 is in the form of a sheet made of lengths of sealing material that have been joined together using a suitable method, for instance welding by the addition of heat. The sheet can have a width of 2 , 4 or 6 metres, for instance. Further, the roof construction includes a device for fixing the sealing layer 3 and the insulating layer 2 to the substructure 1, said device including a plurality of multifunctional attachment members 4. Each attachment member 4 includes an elongate, hollow sleeve 5 of a suitable plastic material, an anchoring element 6 in the shape of a nail, as shown, or a screw, and a rigid joining element 7, supported by the sleeve 5 at its upper end and having a level joining surface 8 that is perpendicular to the longitudinal axis of the sleeve. As further illustrated in Figure 2, the sleeve 5 has a through-running hole 9, which is tapered within the anterior portion 10 of the sleeve to form a narrower whole part 11 with an internal seat 12 for co-operating with a stop head 13 on the anchoring element 6. The sleeve 5 is shorter than the thickness of the insulating layer 2 so that, when the sleeve 5 is in its unloaded state, the anterior end 14 of the sleeve 5 is located at a predetermined distance A from the substructure 1, the sleeve 5 being telescopically displaceable in relation to
the anchoring element 6, downward towards the substructure 1 when loaded from above and upwards when said load is reduced, which upward displacement occurs in co-operation with the rigid joining element 7 and is a result of the spring-back force in the temporarily compressed insulating layer 2. The distance B between the internal seat 12 and the posterior end 15 of the sleeve 5 is greater than said distance A between the anterior end 14 of the sleeve 5 and the substructure 1. The anchoring element 6 is thereby prevented from obtruding out of the sleeve 5 and through the sealing layer 3 when the sleeve 5 is loaded. Said distance A is at least 20 mm, whilst said distance B is at least 10 per cent of the thickness of the insulating layer 2 and not less than 15 mm.
In the preferred embodiment shown, the joining element 7 consists of an electrically conducting joining washer, preferably one that is round and made of a suitable metal material, such as steel plate. In the embodiment shown, the joining washer 7 is loosely connected to the sleeve 5 and to this end provided with a central hole 16 for receiving the sleeve 5 from its anterior end 14, the sleeve 5 being fashioned with a collar-like stop 17 at its posterior end 15 for co-operating with the joining washer 7. To this end the joining washer 7 is provided with a depressed central part 18 for receiving the collar 17. The joining surface 8 has a predetermined minimum size to permit an effective joint between the sealing layer 3 and the joining washer 7 with the aid of an adhesive. To this end, on its joining surface 8, the joining washer 7 has a layer 19 of adhesive attached to the same. The adhesive can be of any suitable type and material whatsoever. An adhesive that can be favourably employed is one that is activated by heat, i.e. is transformed to sticky state, and is non-sticky at temperatures under about 30°C, for instance. The layer 19 of adhesive can be applied to the joining surface 8 of
the joining washer 7 by simply coating the joining surface 8 with a suitable adhesive in the form of a so-called primer, which, once solidified, attaches to the joining surface 8, forming a permanent joint therebetween. The adhesive can also be of a type consisting of two components that are activated by heat to react chemically with each other and form a sticky mass that solidifies in the ambient temperature to form a permanent joint between the sealing layer 3 and the joining washer 7.
If so desired, the sleeve can be provided at its posterior end with a snap element, located a short distance from the collar 17, that is somewhat larger than the thickness of the joining washer 7 so that the joining washer 7 can be snapped past the snap element and received between this and the collar to be retained in this position, inter alia, to facilitate the assembly procedure .
Where the anchoring element 6 consists of a nail, such as illustrated in the drawings, a drill hole 20 for the nail 6 is pre-drilled into the substructure 1 and a drill hole 21 for the sleeve 5 is pre-drilled into the insulating layer 2.
When the attachment members 4 have been anchored in desired locations and the sealing layer 3 laid out on top of the insulating layer 2, the layer 19 of adhesive is activated by being heated with the aid of an external energy source so that the layer 19 of adhesive is transformed to sticky state for adhering to the sealing layer 3 thereby forming a permanent joint once it has solidified. Preferably, heat is applied to the layer 19 of adhesive from beneath, which heat is thus created in situ. Preferably, the energy is supplied from an external source (not shown) , generating heat in the joining washer
7 so that the layer 19 of adhesive is heated by the joining washer 7 to a raised temperature, over 30°C, for instance, to obtain said sticky state. The heat in the joining washer 7 is preferably generated by induction. A device (not shown) for employing this technique can comprise a high-frequency generator and induction apparatus. The generator is connected to a voltage source, the existing electricity supply network, for instance. The induction apparatus has a plane inductor, the copper threads of which are protected by a glass fibre sheet, intended to be brought into contact with the sealing layer 3 above a joining washer 7 of the kind described. The induction apparatus can be designed as a handheld tool with a suitable control device on the handle for controlling the function of the induction coil. With the aid of the induction apparatus, energy is supplied to the joining washer 7 by generating an alternating magnetic field that induces a current in the enclosed joining washer 7 of suitable amperage so that heat is generated in the joining washer 7 and emitted to the layer 19 of adhesive, which is thereby softened and melts to a sticky state, which results in the now sticky layer 19 of adhesive adhering to the underside of the sealing layer 3 and in a permanent joint forming therebetween when the layer 19 of adhesive solidifies again after the induction apparatus has been removed. In other words, the sealing layer 3 will be united by welding with each joining washer 7 in the roof construction .
Short-wave technique can also be used as an energy source, as can any other heat-generating technique that does not affect the sealing layer itself in any detrimental way.
Said joining surface 8 is at least 20 cm2, preferably at least 30 cm2 and most preferred at least 35 cm2, to
provide a sufficient adhesion area for each joining washer.
The expression "permanent joint" means that it resists existing stresses in the roof construction. With the present invention, it is possible to achieve joints between the sealing layer and each attachment member that can tolerate loads of at least 1,500 N without breaking.
The joining element of metal, for instance, can also be placed in the tool in which the sleeve with the collar is manufactured, the tool being modified so that a flange or similar is formed during the injection moulding in a position on the underside of the joining element so that the same becomes a unit with the sleeve.
P1483SE TP1 010614