The present invention relates to a side flashing member for use with a roof penetrating structure installed in an inclined roof surface, said flashing member having a substantially U-shaped cross section to allow water to be drained off along the side of the roof penetrating structure, one arm of the U engaging the roof penetrating structure and the base of the U being substantially in plane with the roof. The invention further relates to a method of making such a flashing member.

When flashing roof penetrating building structures, for example chimneys or frame structures for roof windows, in order to protect them from the weather and to provide a seal between the structure itself and the roof, it is common to use flashing covers of sheet metal, for instance aluminium, copper, steel or zinc. Conventionally, such flashing covers have been manufactured by ordinary tin man work from a plane sheet material which is profiled and formed to make a fit at the desired location. The comparatively costly adjustment and assembly work on location, which is required when using this conventional craftsmanship, may, however, be avoided by use of pre-manufactured flashing members.

Typically, a flashing assembly adapted to be used with a roof window comprises upper and lower flashing members adapted to be mounted in a horizontal position between the roof surface and the upper and lower frame portions of the window, respectively, as well as first and second side flashing members adapted to be mounted in sloping positions between the two side frame portions and the roofing. The above flashing members may be said to form a collar around the window, and to waterproof the joint between this collar and the window the flashing assembly further comprises cap members.

When rain etc. hits the roof above the window, water drains off from the roofing onto the upper flashing member, from there onto the side flashing members, then onto the lower flashing member and finally back onto the roofing below the window.

In some geographical areas roof windows are often mounted in the so-called "Encastrée" manner where the window does not project as far above the plane of the roof as is normally the case. This type of mounting improves the insulation properties and is thought to be more aesthetically pleasing, but due to the fact that drainage water may gather at particularly the bottom of the window, it may entail problems with the draining off of water. This is normally solved by using a lower flashing member with a decreased slope, which may be said to "lift" the water up onto the outer surface of the roofing in stead of merely "deflecting" it. An example of such a flashing is illustrated in the Danish Patent application nr. PA 2002 01847 (not published).

However, when two windows are to be mounted one above the other as described e.g. in DE 202 06 327 U a problem arises with getting water away from the horizontal gutter flashing member used between two such windows. The problem is particularly related to cases, where the gutter is also used to drain off water condensing on the inside of the window, as it must then be located below the level of the inside of the window pane.

A possible solution to the problem might be to give the side flashing members used with the bottom window a smaller slope than the roof, thus making them lie deeper in the roof at the top of the bottom window where they contact the gutter flashing member. Such a difference in slope between otherwise parallel parts of the window and flashing may, however, lead to lack of precision in mounting, possibly caused by a deliberate misfitting in the attempt to make the flashing look nice. Furthermore the overlap between the side flashing and cap members will vary corresponding to the difference in slope, thereby becoming either too small or unnecessarily large at one end. A flashing of roof penetration with sectioned profiles is shown in document DE-A-2422474. It is therefore the object of the present invention to provide a side flashing member which can be used regardless of the type of mounting. In addition it is the obj ect to provide a method of making such a flashing member.

According to the invention a flashing is provided, which comprises a receiving section, a lifting section and a draining section all being formed from a single piece of material, the draining section being in use inclined at substantially the same angle of slope as the roof and, in the mounted state, being positioned below said receiving section seen in the direction of slope and higher than the receiving section seen perpendicular to the roof surface, and the lifting section being arranged between the receiving and draining sections.

This implies that the side flashing member may be used with all types of roof windows and mountings i.e. also for Encastrée mounting, and it is especially well suited for mounting of two windows closely one above the other.

The receiving section is primarily meant to be mounted in direct contact with the gutter flashing member used between two windows mounted one above the other, i.e. as side flashing for the bottom window, and at the same time in contact with the side flashing member of the top window. The water drained off by these other flashing members thus flows onto the receiving section and from there via the lifting section onto the draining section. The receiving section thus must be located sufficiently deep in the roof structure to receive the water drained off by the contacting gutter flashing member and to keep the water from penetrating the joint between these two flashing members.

Presupposing that the material used is in itself watertight, the forming of the three sections from a single piece of material guarantees watertightness, which is essential in the present type of flashing. On the contrary supposedly sealing joints such as welding might be flawed or become deteriorated over time.

For use with typical roof penetrating structures the size of the receiving section primarily depends on the other flashing members connected thereto, i.e. the receiving section must be sufficiently long to accommodate the width of the gutter flashing member contacting the inventive flashing member from the side. In practice, the receiving section will constitute the smaller part of the flashing, while the draining section extends along the bulk of the side of the roof penetrating structure.

In a preferred embodiment, the receiving and draining sections have substantially the same slope, i.e. substantially the same slope as the roof. In this embodiment the receiving section may thus be said to serve only to take up the water, while the lifting section transfers the water from the receiving section to the draining section, thus lifting it from one level to another seen in the direction perpendicular to the roof surface.

The slope of the lifting section preferably, in the mounted state, constitutes a horizontal angle of 0-10° having the same direction of slope as the roof, as it must prevent pools from forming between the lifting and receiving sections. For aesthetical reasons the slope should be as small as possible thereby giving the lifting section the smallest possible extent seen from above perpendicular to the roof surface.

The fact, that the receiving and draining sections both have a slope corresponding to the slope of the roof, entails that the flashing does not penetrate as deeply into the roof structure as if it had had the same slope as the lifting section, thus leaving more room for e.g. insulation.

To minimize the number of items, which has to be kept in stock, it is advantageous that each flashing member can be used in different flashing assemblies, especially with different constellations of roof penetrating structures being arranged close to each other. It is therefore preferred, that the side flashing member has separation means for adaptation to different installation situations. For instance the arm of the U-shaped flashing member engaging the roof penetrating structure may be provide with separation means allowing in-situ adaptation to the gutter flashing used in each particular case. The flashing is preferably provided with separation means for more than one type of contacting flashing, only one of these sets of separation means being used in each case.

The separation means may be printed lines, grooves, notches or embedded strips, and may serve as guides for scoring the material with e.g. a knife or may enable separation without the use of tools. Which is preferred depends on other factors such as the material, thickness or shape of the flashing.

In a particularly preferred embodiment, the side flashing member is connected to or integral with another side flashing member. In this way the joint between neighbouring side flashing members that is otherwise necessary when two windows are mounted side by side may be avoided, thus leading to improved watertightness and a decreased risk of wrongful mounting. Such a side flashing member might be provide with separation means as described above, whereby all windows can be supplied with such a double side flashing member, that can be split and used as ordinary side flashing members when the window is to be used alone.

The further object of the invention, to provide a method of making a U-shaped flashing member as mentioned above, is achieved by a method, where angles between sections are formed by folding the material twice giving it the shape of a Z and subsequently securing at least one part of the Z-shaped fold while pulling on at least one other part to at least partly unfold the Z. By this method it is possible to make a flashing member that is sufficiently watertight and at the same time relatively cheap to manufacture. Furthermore such a flashing may be made from a substantially rectangular piece of material by folding only, thus rendering the use of sealing joints such as weldings superfluous.

The invention will now be explained in detail with reference to the schematic drawings, in which

• Fig. 1 is a perspective view showing the prior art flashing assembly for a two by two configuration of roof windows, and
• Fig. 2 is a perspective view of a flashing member according to the present invention.

In the figures the different components are not necessarily drawn to scale but merely serve to illustrate general principles.

Fig. 1 illustrates the different components of a prior art flashing assembly for four roof windows 1,2 mounted two by two in an inclined roof surface. At the top of the top windows 1 upper flashing members 3 channel the water coming from the roofing above the windows out onto side flashing members 4 running in parallel with the top windows seen in the direction of slope. The side flashing members 4 are substantially U-shaped to prevent water from coming into contact with the window and from penetrating into the roof next to the window. Between the top windows 1 and bottom windows 2 lies a pair horizontal gutter flashing members 5 which collects water hitting the surface of the top windows 1. The gutter flashing members 5 drains the water off onto side flashing members 6 by the bottom windows 2. Below the bottom windows 2 is a pair of lower flashing members 7, which drains off water hitting the lower windows 2. Corner portions 8 of the lower flashing member further leads the water from the side flashing members 6 on onto the roof surface below the windows.

The flashing assembly shown in Fig. 1 is a standard flashing for ordinary roof windows. In some cases the horizontal gutter flashing members 5, however, must be located deep in the structure as they are also used for collection water condensed on the inside of the top windows 1. When this is combined with Encastrée mounting of the windows 1,2, the horizontal gutter flashing members 5 will be located beneath the level of the bottom side flashing members 6 shown in Fig. 1, thus rendering the use of such a prior art flashing unusable.

A side flashing member 100 according to the present invention is illustrated in Fig. 2. It comprises a receiving section 110, a lifting section 120 and a draining section 130. The receiving and draining sections 110,130 are inclined at substantially the same angle A, preferably the same slope as the roof (not shown), while the angle of slope B of the lifting section 120 is small or close to zero. The angle B must obviously be positive, as a pool would otherwise form between the receiving and lifting sections leading to accelerated degradation of the flashing material.

Due to the difference of slope, the receiving section 110 will be located deeper in the roof than the draining section 120, the difference in depth being indicated by the distance d in Fig. 2. It is to be noted, that the flashing is not drawn to scale and that the distance d may well be smaller compared to other parts of the flashing member 100.

The receiving section 110 may also have a smaller angle of slope than the draining section 130, possibly even the same slope as the lifting section 120, thus making them work as one section (not shown). This will allow the horizontal gutter flashing members (not shown) to be located even deeper in the structure. However, in such an embodiment the side flashing member will penetrate deeply into the roof structure, as the distance d will increase, and there will be less room for other elements such as insulation.

In installation situations, in which the side flashing member 100 is utilized for connection with an intermediate member in the form of a gutter flashing member (not shown) to drain off water from the gutter flashing member onto the inventive side flashing 100, the side flashing shown in Fig. 2 must be adapted by making a cut-out in the upright part 111 of the receiving section 110. For this purpose separation means 112 have been provided in the embodiment shown allowing the removal of a portion 113 of the flashing material.

It might also be desirable, to use a side flashing member according to the present invention in connection with a single window or the upper flashing member of a group of windows. In that case the side flashing member 100 could be provide with alternative separation means 114 allowing the corner 111 of the side flashing member to be separated 114' and bent 114'' down to be level with the roof surface.

Each side flashing member 100 may be provided with more than one set of separation means 112,114 thus allowing the use of one side flashing member for many purposes. For instance it might have separation means corresponding to two or more different widths of the gutter flashing member. When mounting the side flashing member the appropriate set of separation means are used leaving the others untouched.

The separation means 112,114 may be printed lines indicating where to cut the material using for instance a pair of plate shears; notches that allows a part of the flashing to be separated from the rest by repeated bending; an embedded strip that may -be pulled from the material thereby weakening it or separating it as known from packs of crackers; or a strip of the material itself being separated from the rest by two notches as know from beverage cans. As hinted, the separation may take place with or without the use of tools, but preferably no special tools should be necessary.

In Fig. 2 the side flashing member 100 has been shown with one arm 101 of the U being upstanding, while the other 102 is level with the roof surface. For use on the other side of the window, a mirror image flashing member (not shown) is provided. When two windows are mounted side by side, the level portions of the two side flashing members are arranged in an overlapping manner. To avoid this joint between neighbouring side flashing members, the side flashing member according to the invention may, however, also have two upstanding arms each meant to engage one of the windows, corresponding to the intermediate prior art side flashing members 4',6' shown in Fig. 1. Alternatively two side flashing members according to the invention may be made in one piece, or they may be provided with engagement means for watertight engagement. In case of the one-piece solution the inventive side flashing member might be provided with separation means as described above allowing in-situ separation. This latter embodiment entails the advantage that all windows can be supplied with such a double side flashing member. When two windows are mounted side by side, one of the these double flashing members is used between them, while the other is split in two for use on the two sides of the windows facing the roof surface. If a window is to be used alone the double flashing member is simply split and used as ordinary side flashing members.

Preferably, the side flashing member 100 shown in Fig. 2 is formed by folding a single piece of sheet material, thus obtaining an excellent watertightness. The forming is performed in three steps: First Z-shaped folds are made where angles are to occur between different portions of the flashing member; then folds are made along the length of the flashing member giving it the U-shape; and finally one or more parts of the Z-shaped folds are secured while pulling on the rest of the folds to at least partially unfold them. By the flashing member in Fig. 2 the Z-shaped fold between the receiving section 110 and lifting section 120 has been secured at the sides 141,142 and unfolded by pulling at the middle 143, thus locally making the flashing member concave. On the contrary the fold between the lifting section 120 and draining section 130 has been secured at the middle 153 and unfolded at the sides 151,152 to give the flashing member -a locally convex shape. As may be clearly seen the transition from the folded to the unfolded state is gradual.

It is also possible to manufacture the side flashing member 100 using other techniques, e.g. deep drawing, compression moulding or the like.

Whereas the present invention has been described with respect to preferred embodiments thereof, it will be understood that various changes and modifications will be suggested to one skilled in the art and it is intended to encompass such changes and modifications as fall within the scope of the appended claims. For example the inventive side flashing member may be used wherever other flashing members are installed deeply in the roof, i.e. not only with windows but also with solar panels and the like.