A roof window and a method for mounting a roof window

Technical Field

The present invention relates to a roof window configured for being mounted in a roof structure inclined in a direction of inclination and comprising a roofing material, said roof window comprising a frame, a sash carrying a pane and a covering assembly, said frame comprising a top frame member, two side frame members and a bottom frame member configured to extend horizontally and be arranged lowermost in the mounted state when seen in the direction of inclination, said frame members together defining a frame opening and a frame plane, and each of said frame members extending in a length direction and each having an outer side facing away from the frame opening and extending in a height direction from an interior side to an exterior side, said exterior side being configured for facing away from an interior of a building covered by the roof structure in a mounted state, and said covering assembly comprising a plurality of flashing members for covering a joint between the frame and the roof structure, wherein a top flashing member extends along the top frame member, a bottom flashing member extends along the bottom frame member, and at least two side flashing members extend along the side frame members in the mounted state. The invention further relates to method for mounting a roof window.

Background Art

When installing roof windows in a roof structure of a building it is necessary to make an opening in the roof structure and subsequently to reestablish the weatherproofing of the building otherwise provided by the roof structure. For this purpose, the joint between the roof window and the roof structure is covered by a covering assembly including flashing members and cladding members. To achieve the best possible weatherproofing, it is essential that the covering assembly is mounted correctly and that it subsequently stays in place, even during heavy winds and when affected by big temperature variations.

Summary of Invention

With this background, it is therefore an object of the invention to provide a roof window with an improved covering assembly and a method for mounting a roof window.

This and further objects are achieved with a roof window of the kind mentioned in the introduction, which is furthermore characterised in that the exterior side of the bottom frame member comprises an inclined flashing engagement surface forming an obtuse angle with the outer side of the bottom frame member.

The inclined flashing engagement surface allows the bottom flashing member to be brought into contact with the frame by displacing the bottom flashing member in a direction parallel to the frame plane and perpendicular to the bottom frame member by lifting a leading edge of the bottom flashing member and helping to guide the bottom flashing member into place. In this way, the bottom flashing member may be brought in underneath another part of the roof window or be slid into engagement with another flashing member, an interface unit, or the like. This provides increased versatility compared to most prior art covering assemblies, where the bottom flashing member is typically mounted by lowering it into contact with the frame in a direction perpendicular to the frame plane, often necessitating a particular mounting sequence or even removal of other components. ,

The angle between the inclined flashing engagement surface and the outer side of the bottom frame member is to be understood as the interior angle measured within the boundaries of the bottom frame member. Due to the angle being obtuse, the flashing engagement surface will be located lower at the outer side of the bottom frame member than at an inner side of the bottom frame member opposite the outer side when seen in the height direction.

To help keep the bottom flashing member in place once mounted, the exterior side of the bottom frame member may comprise a flashing retention recess at the inner side of the bottom frame member opposite the outer side. This recess may receive an edge projection at the leading edge of the bottom flashing member, so that the bottom flashing member hooks onto the bottom frame member and the edge projection serves as a barb hindering or preventing a retraction of the bottom flashing member once it has been mounted. During mounting, the displacement of the bottom flashing member is continued until the edge projection comes into engagement with the flashing retention recess. The engagement may result in a tactile feed-back to the installer indicating that the bottom flashing member has been mounted correctly. If the bottom flashing member is made from aluminium or a material with similar elasticity, the leading edge may be bent upwards in relation to the rest of the bottom flashing member due to the contact with the flashing engagement surface and the edge projection may then snap into the flashing retention recess. The edge projection may be a flange extending over substantially the entire length of the bottom flashing member, but it is also possible to employ one or more local projections.

The inclined flashing engagement surface preferably extends at an angle of 110-160 degrees, more preferably 115-140 degrees, still more preferred 120-130 degrees with respect to the outer side of the bottom frame member. The optimal angle will depend on factors such as the material used for the bottom frame member and/or the bottom flashing member, the space available over the bottom frame member, and the dimensions of the bottom frame member, and it may be determined by simple experiments.

The flashing engagement surface may be provided on a traditional frame member, such as a wooden frame member, a frame member made from a wood-based core encased in a polymer, or a frame member made by extrusion, but is also possible to provide the frame with an interface unit and forming the flashing engagement surface therein. The interface unit may for example comprise an elongate element, such as a rail, provided on an exterior side of a traditional frame member and extending in the length direction thereof. The frame may also comprise one or more shorter interface unit elements.

In one embodiment, the bottom frame member comprises a bottom element of an interface unit and this bottom element comprises a tool recess allowing the insertion of a tool between the bottom flashing member and the bottom frame member. Such a tool recess, which remains uncovered by the bottom flashing member, allows for the later insertion of a tool, which can then be used to lift the bottom flashing member off the bottom frame member. This may for example be advantageous in connection with maintenance and repair but will also facilitate disassembly for recycling at the end of the life of the roof window. The tool might for example be a screwdriver or a similarly elongate tool, but it is also possible to lift the bottom flashing by hand by inserting a finger in the tool recess. A tool recess may also be provided in a bottom frame member not comprising an interface unit element.

The covering assembly may further comprise a plurality of cladding members each for covering a part of the sash and overlap with at least one flashing member, thereby covering joints between the sash and frame and between the frame and the flashing members.

In one embodiment, the roof window further comprises a reinforcement element arranged between the bottom flashing member and the bottom frame member, possibly attached to the bottom frame member by screws or like fasteners. The reinforcement element may reduce the risk of the bottom flashing member being pulled off the bottom frame member, for example under the influence of wind, by fixating the bottom flashing element in the height direction or creating a tension in the bottom flashing element hindering a movement in the height direction.

The reinforcement element may comprise a section extending along the outer side of the bottom frame member and a section extending along the exterior side of the bottom frame member, said sections preferably being substantially perpendicular to each other.

The reinforcement element may comprise a projection projecting into a recess on the outer side of the bottom frame member and extending in parallel to a section extending along the exterior side of the bottom frame member. The projection will help to prevent an upwards movement of the reinforcement element in the height direction.

The reinforcement element may engage with bent edges on the bottom flashing element, so that it is fixated in relation to the bottom flashing element.

The reinforcement element may extend over the entire length of the bottom frame member, but it is presently considered advantageous that the reinforcement element has a length in the length direction constituting between 1 :10 and 1 :2 of the length of the bottom frame member.

The reinforcement is preferably made from sheet metal by bending or from a polymer by moulding and is preferably elastic.

The advantages provided by the reinforcement element will apply even if the bottom frame member does not comprise an inclined flashing engagement surface.

A second aspect of the invention relates to a method for mounting a roof window in a roof structure inclined in a direction of inclination and comprising a roofing material, said roof window comprising a frame and a sash carrying a pane element, said frame comprising a top frame member, two side frame members and a bottom frame member, said frame members together defining a frame opening and a frame plane and each extending in a length direction, and each of said frame members having an outer side facing away from the frame opening and extending in a height direction from an interior side to an exterior side, wherein said method comprises the steps of: A) arranging the roof window in an opening in the roof structure with the bottom frame member extending horizontally and being arranged lowermost when seen in the direction of inclination, and with the exterior sides of the frame members facing away from an interior of a building covered by the roof structure, and B) arranging a plurality of flashing members so that they cover a joint between the frame of the roof window and the roof structure with a top flashing member extending along the top frame member, a bottom flashing member extending along the bottom frame member, and at least two side flashing members extending along the side frame members, characterised in that during step B) the bottom flashing member is displaced in a direction parallel to the frame plane and perpendicular to the bottom frame member thereby bringing a leading edge of the bottom flashing member into engagement with an inclined flashing engagement surface on the exterior side of the bottom frame member, said flashing engagement surface forming an obtuse angle with the outer side of the bottom frame member.

Embodiments and advantages described with reference to the first aspect of the invention also apply to the second aspect of the invention and vice versa.

Brief Description of Drawings

In the following description embodiments of the invention will be described with reference to the schematic drawings, in which

Fig. 1 is a perspective view of a roof window with a covering assembly,

Fig. 2 is a perspective view showing the mounting of a bottom flashing member,

Fig. 3 is a cross-sectional view showing a bottom flashing member arranged on a bottom frame member,

Fig. 4 is a perspective cross-sectional view showing the lower left corner of the roof window in Fig. 1 ,

Fig. 5 corresponds to Fig. 4 but showing a cross section at the line V- V in Fig. 4,

Fig. 6 corresponds to Fig. 5 but with a second flashing element of the bottom flashing member removed,

Fig. 7 is a perspective view of a bottom flashing member arranged on a bottom frame member,

Fig. 8 is a cross-sectional view showing a bottom flashing member arranged on a bottom frame member,

Fig. 9 is a cross-sectional view of a reinforcement element, and

Fig. 10 is a perspective view of parts of a bottom flashing member arranged on a bottom frame member.

Description of Embodiments

Referring initially to Fig. 1 , a roof window 1 is shown with a covering assembly 10, wherein the right-hand side of the top flashing member 1011 is shown in a state of delivery, before adaptation to the shape of a roofing material (not shown). The roof window 1 is shown in an inclined position as it is intended for being mounted in an inclined roof structure.

In addition to the top flashing member 1011 , the covering assembly 10 comprises a plurality of side flashing members 1012, 1013, a bottom flashing member 1014, and a plurality of cladding members 1021 , 1022, 1023, 1024 each covering a part of the sash carrying the pane 4 and overlapping with one or more flashing members.

The roof window 1 comprises a frame (not visible in Fig. 1 ), and the top flashing member 1011 , the side flashing members 1012, 1013, and the bottom flashing member 1014 extend in a respective length direction L along top, side, and bottom frame members, respectively. The frame members together define a frame opening covered by the pane 4 and a frame plane F.

In Fig. 2 the roof window 1 is shown mounted in a roof structure 11 with a roofing material 112 and a direction of inclination D.

The mounting of the covering assembly starts with the mounting of the bottom flashing member 1014, which is displaced in a direction parallel to the frame plane F and perpendicular to the length direction L of the bottom frame member 24.

As shown in Figs 3 and 4, the exterior side 20e of the bottom frame member 24 comprises an inclined flashing engagement surface 241 forming an obtuse interior angle S with the outer side 20o of the bottom frame member 24. The flashing engagement surface is thus located lower at the outer side of the bottom frame member than at the inner side 20s when seen in the height direction H. In the embodiment shown the angle S is 125 degrees.

When the bottom flashing member 1014 is mounted by displacement in a direction parallel to the frame plane F and perpendicular to the length direction L of the bottom frame member 24 as indicated by the double arrow in Fig. 3, the leading edge 1014e of the bottom flashing member 1014, which here comprises an edge projection 1014p, comes into engagement with the flashing engagement surface 241. As the bottom flashing member 1014 is displaced further, this contact will result in the leading edge 1014e being lifted, thereby helping it to slide into place. In the embodiment shown, the exterior side 20e of the bottom frame member 24 comprises a flashing retention recess 242 at the inner side 20s of the bottom frame member 24 opposite the outer side 20o of the bottom frame member 24. When the bottom flashing member 1014 has been displaced sufficiently far, the edge projection 1014p, here in the form of a bent flange, falls or snaps into the flashing retention recess 242, so that the bottom flashing member hooks onto the bottom frame member 24. In this way, the mounted bottom flashing member 1014 will be prevented from sliding away from the bottom frame member 24 under the influence of gravity or from being pulled off unintentionally.

Turning now to Fig. 5, which shows a cross-section along the line V-V in Fig. 4, it is seen that the bottom frame member 24 is provided with a bottom element 84 of an interface unit 8 and that a section of the inclined flashing engagement surface 241 is formed by this bottom element 84. It is, however, to be understood that the frame 2 does not need to include an interface unit 8.

As is seen in Fig. 6, where a part of the bottom flashing member 24 has been removed, the bottom element 84 of the interface unit 8 comprises a tool recess 243. The tool recess 243 extends deeper than the edge projection 1014p such that a part of the tool recess 243 remains uncovered by the bottom flashing member 1014, thereby allowing the insertion of a tool, such as a screwdriver, between the bottom flashing member 1014 and the bottom element 84. In this way, the tool can be used for lifting the bottom flashing member 1014 off the bottom frame member 24 if needed. A tool recess 243 might also or alternatively be provided in the bottom frame member 24, for example if the roof window 1 does not include an interface unit 8.

The bottom element 84 shown does not include a flashing retention recess 242, but it is to be understood that other embodiments might do so.

As is seen in Fig. 3, a recess 244 may be provided in the exterior side 20e of the bottom frame member 24 and/or in a bottom element 84 of an interface unit 8. The recess may serve to drain off any condensation forming on the interior side of the bottom flashing member 1014 or accommodate a sealing strip. The flashing engagement surface 241 may extend over the recess as shown in Fig. 7 or from the recess as shown in Fig. 3.

In the embodiment in Fig. 1-6, the bottom flashing member 1014 comprises a first flashing member 1015 and a second flashing member 1016, which are interconnected in sliding engagement to allow their relative position to be adjusted during mounting. This, however, does not need to be the case, as illustrated by the alternative embodiment in Fig. 7-8 showing a bottom flashing member 1014 for use with a with a profile roofing material, such as tiles, and comprising a frame attachment element 1014f and a skirt element 1014s.

As seen in Fig. 8, the bottom flashing member 1014 may comprise a reinforcement element 1014r, extending underneath the frame attachment element 1014f from a bent edge, where the frame attachment element is connected to the skirt element, to the edge projection 1014p, which in this case is folded into a double layer section as seen in the enlargement. The reinforcement element is thus locked in relation to the bottom flashing member 1014.

The reinforcement element 1014r comprises a projection 1014r1 projecting into a recess 245 on the outer side 20o of the bottom frame member 24 and extending in parallel to the section 1014r2 extending along the exterior side of the 20e of the bottom element 84. In this way the reinforcement element is fixated in relation to the bottom element in the height direction H, and the risk of the bottom flashing member 1014 being pulled off the bottom element 84 and the bottom frame member 24, for example under the influence of wind, is thus reduced.

It is noted that even though the bottom element 84 shown in Fig. 8 does not comprise a flashing retention recess as in Fig. 3, the bottom flashing member will hook onto and possible snap onto the bottom element in the same way as described above.

Another, simpler reinforcement element 1014r is shown in Fig. 9. In the mounted state, this reinforcement element extends only from the recess 245 and the section 1014r2 configured for extending along the exterior side of the bottom element 84 or the bottom frame member 24 is somewhat shorter so that it does not necessarily extend as far towards the edge projection 1014p as shown in Fig. 8. This reinforcement element may thus not be fixated in relationship to the bottom flashing member 1014, but will span the space between the edge projection 1014p and the section 1014h of the bottom flashing member extending in parallel with the edge projection, i.e. in the height direction H. The tension thereby created will hinder that the bottom flashing member 1014 is pulled off the bottom element 84 and the bottom frame member 24.

The reinforcement element 1014r in Fig. 9 can be attached to the bottom frame member 24 or the bottom element 84 means of screws or like fasteners (not shown) inserted through openings (not visible in Fig. 9) in depressions 1014r3. The depressions are not strictly necessary, but they will allow a tight contact between the sections of the bottom flashing member 1014 and the reinforcement element 1014r extending in the height direction H. Furthermore, the depressions may create a distance between the outer side 20o of the bottom frame member 24 and/or the bottom element 84, which may contribute to the creation of tension in the bottom flashing member as described above.

In both embodiments of the reinforcement element 1014r is made from sheet metal, and the projection 1014r1 is made by bending so that it comprises two layers of material. Other embodiments are, however, possible as long as the projection in able to engage properly with the recess 245.

The relative lengths of the two reinforcement elements 1014r shown in Fig. 8 and 9 are shown in Fig. 10, where a bottom flashing member 1014 is shown without the frame attachment element and mounted at a bottom frame member 24 with bottom elements 84. The reinforcement element of the type shown in Fig. 8 is shown on the bottom frame member 24, while the reinforcement element of the type shown in Fig. 9 is shown next to it. As may be seen, the reinforcement element of the type shown in Fig. 8 has a length corresponding to about half the length of the bottom frame member 24, while the reinforcement element of the type shown in Fig. 9 has a length corresponding to about a quarter of the length of the bottom frame member. The longer the reinforcement element, the stronger the force applied to the bottom frame member. The embodiment in Fig. 8 thus provides a very strong fixation of the bottom flashing member 1014, but it could be even stronger if the reinforcement element 1014r extended over the entire length of the bottom frame member 24. Experiments have, however, shown that a very strong attachment may make it difficult to mount the bottom flashing member and/or created unwanted tensions. The embodiment in Fig. 9 is therefore presently considered advantageous, at least for use in some climate zones.

As is also seen in Fig. 10, the recess 245 does not need to extend over the entire length of the bottom frame member 24, but to facilitate installation of the reinforcement element 1014r, it is preferably slightly longer than the projection 1014r1 . In the embodiment shown, the recess is considerably longer than the reinforcement element to allow the use of a longer reinforcement element where necessary. It is also possible to use two or more shorter reinforcement elements. This may especially be advantageous with larger roof windows and may allow the attachment force provided by the reinforcement elements to be distributed more evenly on the bottom flashing member.

Components of the roof window 1 are easily disassembled and each component may in principle be reused, be recycled by appropriate environmentally responsible disposal means, or the material be recovered for other uses.

List of reference numerals

1 Roof window

10 Covering assembly

1011 Top flashing member

1012 Side flashing member

1013 Side flashing member

1014 Bottom flashing member

1014e Leading edge

1014p Edge projection

1015 First flashing member

1016 Second flashing member

1021 Cladding member

1022 Cladding member

1023 Cladding member

1024 Cladding member

11 Roof structure

112 Roofing material

2 Frame

20e Exterior side of frame member

20o Outer side of frame

20s Inner side of frame

24 Bottom frame member

241 Flashing engagement surface

242 Flashing retention recess

243 Tool recess

25 Recess

4 Pane

8 Interface unit

84 Bottom element

D Direction of inclination

F Frame plane

H Height direction

L Length direction

5 Angle of flashing engagement surface