The invention relates to a method for tightening a roofing underlay, which is placed below battens, which supports a roof overlay such as a tile roof.

The invention also relates to a U-profile for tightening a roofing underlay, which is situated below battens, which support a roof overlay such as a tile roof. The invention furthermore relates to application of U-profile.

Roofing underlays are often used in modern buildings as footing for a roof overlay, for example a tile roof where the roofing underlay is mounted below the battens, which support the roof overlay.

Most often, the roofing underlay consists of a polymeric flexible material, which is delivered in rolls, from which it is extracted when the roof construction is mounted. A roofing underlay, which is thus mounted below a roof overlay will easily flap when wind flows through the roof construction.

Such a flapping is noisy and can therefore be a nuisance for the residents in the building and flapping can cause tear and wear on the roofing underlay with a subsequent risk for its destruction.

It is therefore important that the roofing underlay, after mounting, is tightened such that flapping can be reduced to an acceptable level. From patent nr. WO 95/21974 is known a method and an item for tightening of roofing underlay, where the item contains a spring, which is used as power source for stretching between battens and roofing underlay.

It has been found, however, that the known technique involves some drawbacks, including that items with springs are relatively expensive to produce and time demanding to mount and moreover, are manufactured from a hard material, which easily destroys the roofing underlay by inappropriate mounting.

Another type of roofing underlay tighteners are also known, which consist of a product manufactured from a material, similar to foam rubber, which is shaped as for example a pipe, and which is fastened between batten and roofing underlay by application of a self-locking strip, which is put through the pipe hole and around the batten to which it is to be fastened. This type of roofing underlay tighteners also have drawbacks, including that it is time-consuming to mount roofing underlay tighteners with strips and it is time-consuming and difficult to bring along these roofing underlay tighteners, which are delivered as separate single items. For both of the mentioned known techniques it is furthermore a safety problem that the fitter must use both hands to carry out the mounting and he can therefore not support his hands with a subsequent increased risk for fall from the roof construction. It is therefore an object of the invention to improve the known technique including method, roofing underlay tighteners and application.

The object of the invention is achieved by a method of the type stated in the introductory portion of claim 1 , which is characterized in that U-profile shaped roofing underlay tighteners are mounted between the roofing underlay and the battens. By application of U-profile shaped roofing underlay tighteners it can be achieved that these can be mounted without application of mounting aids such as strips.

By an appropriate shaping of the U-profile shaped roofing underlay tighteners, these can be mounted to the battens in the way that the opening in the U-profile squeezes around the batten to which it is to be fastened and thereby secured solely by the friction between the U-profile tightener and the batten.

The advantage is also achieved that the U-profiles can be mounted by using only one hand whereby the fitter can support his balance with the free hand and thereby reduce the risk of plummeting.

Further appropriate embodiments of the method are stated in claim 2. As mentioned, the invention also relates to a U-profile. This U-profile is characterized in that the U-profile has an opening with a width, which corresponds to the width of the batten, which it is to be mounted to, and a depth which is between 5 and 100 mm, preferably between 20 and 50 mm, where the U-profile furthermore has a width, which is between 10 and 100 mm, preferably between 40 and 70 mm, and where the U-profile has a thickness of material in continuation of the opening, which is between 5 and 100 mm, preferably between 20 and 60 mm and where the thickness of material from the bottom of the opening to the surface, which stretches the roofing underlay (2) is between 10 and 200 mm, preferably between 40 and 100 mm more, preferably between 50 and 70 mm. Hereby, it becomes possible to achieve that the U-profile fits the batten to which it is to be mounted, in such a way that it can be mounted to the batten without application of aids including strips, screws and tools. The stated dimensions also ensure that the roofing underlay in an appropriate way is stretched by the pressure, which occurs against the roofing underlay from the U-profiles, which are mounted to the battens, which are placed between the roofing underlay and the roof overlay. Further appropriate embodiments appear from claims 4 to 6.

The invention will now be explained more fully with reference to the drawings, in which: Fig. 1 shows a roof construction with roofing underlay, battens and roof overlay, where U-profile shaped roofing underlay tighteners are mounted to the battens.

Fig. 2 shows a simplified diagram of an U-profile shaped roofing underlay tightener.

In fig. 1 is with 1 shown a roof construction built around trusses 3 and where there is mounted a roofing underlay 2 typically consisting of rolled out sheets of cloth manufactured from a flexible material, which is to protect trusses 3 and other below placed building parts against for example water, which permeates the roof overlay 7.

The roofing underlay 6 is placed below battens 4,5, which support the roof overlay 7, which for example can be assembled from tiles.

In fig. 1 is shown a number of U-profile 6 shaped roofing underlay tighteners, which are mounted to battens 4,5, which support the roof overlay 7, such that the U-profile 6 shaped roofing underlay tighteners are mounted to those battens 4, which are closest to the roofing underlay 2. In fig 1 is shown a 5:1 magnified segment of one of the U-profile 6 shaped roofing underlay tighteners, which are placed between the battens 4,5 and the roofing underlay 2.

In fig. 2 is shown a U-profile 6 shaped roofing underlay tightener, which is characterized in that the U-profile 6 has a opening 13 with a width 8, which corresponds to the width of the batten 4,5, which it is to be mounted to and a depth 9, which is between 5 and 100 mm, preferably between 20 and 50 mm, where the U-profile furthermore has a width 12, which is between 10 and 100 mm, preferably between 40 and 70 mm, and where the U-profile has a thickness of material 11 in continuation of the opening 13, which is between 5 and 100 mm preferably between 20 and 60 mm, and where the thickness of material 10 from the bottom of the opening 13 to the surface 14, which stretches the roofing underlay 2, is between 10 and 200 mm, preferably between 40 and 100 mm more, preferably between 50 and 70 mm.

The width 8 of the opening in the U-profile 6, which corresponds to the width of the batten 4,5, which it is to be mounted to, will in a preferred embodiment be equal to the width of the batten or less than this, preferably 1 to 5 mm narrower.

It is hereby achieved that the U-profile shaped roofing underlay tightener will squeeze around the batten 4,5, to which it is mounted and thereby increase the friction between the items and thereby the attachment.

In a preferred embodiment, the U-profile 6 shaped roofing underlay tighteners are manufactured from a polymeric and preferably elastic material where polyethene has shown to be especially appropriate.

It has been found to be appropriate to manufacture the U-profile 6 shaped roofing underlay tighteners in modules including in rows, which can easily be separated without use of tools.

Hereby, the transportation of the U-profile 6 shaped roofing underlay tighteners is eased when these for example are brought by roof fitters.

With the invention it is achieved that the U-profile 6 shaped roofing underlay tighteners are inexpensive to manufacture and quick and simple to transport and mount.

Furthermore, the U-shaped 6 roofing underlay tighteners are manufactured in the stated materials and long-lasting dimensions.