Side flashing member, method of making such a side flashing member and a flashing assembly.
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 flashing assembly comprising such a side flashing member and to a method of making it .
When flashing roof penetrating building struc- tures, 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 flashings of sheet metal, for instance aluminium, copper, steel or zinc. Conventionally, such flashings 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 re- quired 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 be- tween 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 "Encastree" 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 illus- trated 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 to small or unnecessarily large at one end.
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 object to provide a method of making such a flashing member.
According to the invention a flashing is provide, which comprises a receiving section and a draining section, the draining section being 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 at least a part of the receiving section seen perpendicular to the roof surface.
This implies that the side flashing member may be used with all types of roof windows and mountings i.e. also for Encastree 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 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.
For use with typical roof penetrating struc- tures 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 flashing member further comprises a lifting section arranged between the receiving and draining sections, and in the mounted state the receiving and draining sections have substantially the same slope, while the lifting section is horizontal or has a relatively small slope in the same direction as the receiving and draining sections. This embodiment may be said to constitute a division of the receiving section as described above, the first or receiving section serving only to take
up the water, while the second or 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 constitutes a horizontal angle of 0-10°, 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 visual extent.
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 pene- trate 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.
One of the most important qualities of flashing members of the present kind is watertightness and it is therefore preferred, that the flashing is formed from a single piece of material . Presupposing that the material itself is watertight and that the shaping of the material has not ruptured it, this guarantees watertightness, whereas supposedly sealing joints such as welding might be flawed or become deteriorated over time.
The inventive flashing member can be made from any suitable material such as plastic or rubber, but in a preferred embodiment is made from metal, pref- erably aluminium or aluminium alloys. Depending on the material, it might be given a surface coating, and different materials may be used in combination. Examples of such combinations is a sandwich structure
of aluminium and bitumen as known from other types of flashings or expanded metal covered with rubber to make it watertight.
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 gut- ter' 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 ma- terial, 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, thus forming a double 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 inventive side flashing member and in particular the double side flashing member, may form part of a flashing assembly for use with roof penetrating structures mounted in a group comprising at least three structures, at least one structure being mounted above another and at least one structure being mounted to the side of another. Advantageously such a flashing assembly may further comprise gutter flashing members for use between structures mounted one above the other, at least one of these gutter flashing members having separation means for dividing it into a top and a bottom flashing member for use above and below the group, respectively. Such gutter flashing members are described in Danish patent ap- plication PA 2002 01919 (not published) . The flashing assembly may further comprise other adaptable flashing members as for instance the ones described in Danish patent application PA 2002 01919 (not published) . 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 se- curing 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,
Fig. 2a and 2b are perspective views of a flashing member according to the present invention showing two different configurations of separation means, Fig. 3 is a perspective view of en double side flashing member for use between windows mounted side- by-side, and
Fig. 4 is a perspective view corresponding to the one in Fig. 1 showing a flashing assembly accord- ing 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 used with 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 side frame portions of the top windows. 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 lay 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 fur- ther leads the water off from the side flashing members 6 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, how- ever, must be located deep in the structure as they are for example also used for collection water condensed on the inside of the top windows 1. When this is combined with Encastree 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 such a prior art flashing assembly unusable.
A side flashing member 100 according to the present invention for use on the left side of the window seen from the outside is illustrated in Fig. 2a. 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. 2a. It is to be noted, that the flashing is not drawn to scale and that the distance d may well be e.g. 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 flash- ing 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.
Before installation the inventive side flashing 100 shown in Fig. 2a and 2b must be adapted by making a cut-out in the upright part 111 of the receiving section 110. For this purpose separation means 112,112 ' ,114 ' ,11 ' ' have been provided allowing the removal of a portion 113,113' of the flashing material .
In Fig. 2a the bottom of the portion 113 is approximately level with the underside of the roofing material (not shown) and with the opposite side portion 104 of the side flashing member. Such a side flashing member is used, when the gutter flashing is located substantially above the level of the roof.
For use with gutter flashings located deeply in the roof as previously described the separation means 112' must, however, allow the removal of a larger portion 113' as shown in Fig. 2b showing a side flashing member for use on the right side of the window. To prevent water from flowing backwards into the gutter flashing (not shown) or possibly penetrating into the underlying structure, the bottom of the portion 113 ' to be removed must be located at a distance above the bottom of the receiving section 110. If, for some reason, the removal of the relatively large portion 113 ' of the flashing member is disadvantageous a portion having no contact with the edge of the flashing may also be removed, thus leaving for example a circular hole (not shown) in the side 111. 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 ',114'' shown in Fig. 2a allowing the corner 111 of the side flashing member to be separated 114 ' and bent 11 ' ' down to be level with the roof surface . Each side flashing member 100 may be provided with more than one set of separation means 112,112 ', 114 ', 114 ' ' thus allowing the use of a standard side flashing member for many purposes. For instance it might also have separation means corre- sponding 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 , 112 ' , 114 ' , 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 bev- erage cans. As hinted, the separation may take place with or without the use of tools, but preferably no special tools should be necessary. The separation means may also have different colour codes or the like to help the person performing the separation to choose the right one.
In Figs. 2a and 2b the side flashing member 100 has been shown with one arm 101 of the U being upstanding, while the base 102 is level with the roof surface. In the embodiment shown, the U-shape is one with sharp corners. It is, however, to be understood that the inventive flashing member may come in many other configuration, as long as the overall shape is not altered significantly. For example, the U might have rounded corners or the base might be convex giv- ing the flashing member a shape resembling a W or concave giving it a V-like shape.
The flashing members in Fig. 2a and 2b are mirror images, and when two windows are mounted side by side, the level portions of the two side flashings 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 also, as shown in Fig. 3, have two up-
standing arms 101', 101'' each meant to engage one of the windows, one of which is indicated by a part of the window frame 10. This double side flashing member has two receiving sections 110, one on each side, and, correspondingly, two lifting sections 120 elevating the water to the level of a common draining section 130 ' .
Between the two receiving and lifting sections is a connecting portion 106 corresponding to the joint side portions 104 of two single side flashing members. The connecting portion 106 is substantially level with the draining section 130' and its width allows the double flashing member to "ride" on the rafter 9, the two receiving sections 110 being lo- cated on each side of the rafter.
If the neighbouring windows are mounted high in the roof or if no rafter is present between them, the double side flashing member may also be formed without the connecting portion 106, i.e. with only one receiving and one lifting section spanning the width between the two windows .
The side flashing member in Fig. 3 is provided with separation means 105 as described above allowing in-situ separation. This embodiment entails the ad~ vantage 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.
Alternatively two side flashing members according to the invention may be provided with engagement means for watertight engagement, e.g. an adhesive
tape.
Preferably, the side flashing members are formed by folding a • single . piece of sheet material, thus obtaining an excellent watertightness. The for - ing 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 members in Figs. 2a and 2b the Z-shaped fold between the receiving section 110 and lifting section 120 has been secured at the sides 141,142 and un- folded 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.
Fig. 4 shows the use of a side flashing member as described above in a flashing assembly used with four roof windows mounted in a two-by-two configuration. The flashing assembly corresponds to the prior art flashing assembly shown in Fig. 1 and like members are given like reference numbers with 10 added thereto. Thus the flashing member 14 in Fig. 4 fulfils substantially the same purposes as the flashing
member 4 in Fig. 1.
At their upper ends in the mounted state the side flashing members 16 are formed as shown in Fig. 2a and 2b and the flashing member 16' as shown in Fig. 3. It is to be understood that the length of the draining section may be chosen freely as it has no essential influence on the functionality of the side flashing member.
The gutter flashing members 15 of Fig. 4 are located deeply in the roof and relatively large portions have therefore been removed from the side flashings members 16, 16'.
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 flash- ing 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.