523969
No: 523969
Date: 4 February 2003
NEW ZEALAND
Patents Act 1953
COMPLETE SPECIFICATION
A FLASHING
WE, VERSATILE BUILDINGS LIMITED a New Zealand company of 112 Waterloo Road, Sockburn, Christchurch, New Zealand do hereby declare the invention, for which we pray that a Patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement:-
1
INTELLECTUAL PROPERTY OFFICE OF N.Z.
- 4 FEB 2004
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RECEIVED
2
TITLE OF INVENTION A FLASHING BACKGROUND TO THE INVENTION
This invention relates to a flashing for use in building construction.
With the recent controversy concerning the so-called ""leaking building" syndrome, there is a perceived need for more effective flashing systems with building constructions in order to prevent or significantly minimise the possibility of damage from the ingress of moisture. This applies equally to what could be termed more simple cladding systems where a pressed metal cladding is applied directly to a framing system such as used for the building of garages, sheds and low cost cabins. The present invention has particular application to such building systems.
A problem which can also exist with such building systems is ""cupping" of the cladding profile. Not only is the occurrence of ""cupping" of the cladding unsightly, but can also result in lack of weatherproof ing when the cupping occurs in the vicinity of a joint between adjacent sections of cladding profile, windows, doors and openings.
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For the sealing of joins between adjacent cladding profiles and cladding profiles with overlapping exterior sealing elements, it is known to use a back-flashing. Generally, the back-flashing is located with the framing and will incorporate some means of anchoring a portion of the exterior sealing element. To provide flashing both on the flat and at corners, such flashing elements are generally ^flat" or ^angled". This means that the builder must have a supply of both flat and angled back-flashing elements.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a back-flashing which provides improved water tightness.
It is a further object to provide a back-flashing which can provide support for a cladding profile in order to prevent cupping of the profile.
A further object is to provide back-flashing of a construction which makes it versatile in its end use.
Broadly according to one aspect of the invention there is provided a back-flashing including an elongate element, mounting means extending longitudinally along the elongate element for the mounting and, in use, of an exterior sealing element and partition means extending
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longitudinally along the elongate element and located to at least one side of the mounting means.
In the preferred form of the invention the mounting means is formed by a series of end to end spaced apart elongate mountings. Each mounting is preferably formed by a pair of spaced apart fins defining a groove or slot into which a leg portion of an exterior sealing element can engage.
Preferably opposing surfaces of the fins have serrations or some other form of gripping surface.
According to the preferred form of the invention the partition means are located to each side of the mounting means. Preferably the partition means is a series of end to end spaced apart walls. Preferably the walls project from a surface of the elongate element to substantially the same height as the mountings project from said surface.
The preferred form of the invention also provides a back-flashing in which a marginal elongate element is hingedly coupled (preferably continuously) to a long edge of the elongate element. In the preferred form the marginal elongate element is formed integrally with the elongate element, the hinge coupling being a flexible area of reduced thickness of the material from which the back-flashing is formed.
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BRIEF DESCRIPTION OF THE DRAWINGS
In the following more detailed description of the invention reference will be made to the accompanying drawings in which:-
Figure 1 is a plan view of a part of the length of a back-flashing according to the present invention,
Figure 2 is a cross-section on line A-A of Figure 1 but on enlarged scale,
Figure 3 is a side elevation view of the back-flashing as shown in Figures 1 and 2,
Figure 4 is an end elevation view of a profile of exterior pressed sheet metal cladding material which can typically be used with the back-flashing of the present invention,
Figure 5 is a perspective view of the back-flashing in its folded configuration,
Figure 6 is a perspective view of the back-flashing according to the present invention as used in one configuration in conjunction with the metal cladding of Figure 4,
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Figure 7 is a section view of the back-flashing and metal cladding where metal cladding is fixed to a timber frame, and
Figure 8 is an elevation view of the arrangement shown in Figure 7.
DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INVENTION
The back-flashing according to the present invention is, in its preferred form, extruded from a plastic material. The back-flashing element 10 includes an elongate, relatively thin body 11. Along one long edge thereof is hingedly coupled a marginal element 12.
The main body 11 and marginal element 12 are preferably formed in one piece. The marginal element 12 is joined to the main body 11 by an area of flexible material of reduced thickness 13 so as to form a hinge. Figure 5 shows the marginal element 12 in the folded conf igurat ion.
Thus the marginal element 12 can either be positioned to lie substantially in the plane of the main body 11 (see Figure 7) or can be hinged about the hinge 13 to the ""folded11 position as shown in Figures 1, 2 3 and 5 where it lies substantially at right-angles to the plane of the
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main body 11. When the marginal element is so hinged into the position shown in the drawings, the back-flashing can be used as an "angle" back-flashing, and thus is particularly useful as a flashing around door and window openings. When the marginal portion 12 is in the plane of the main body 11, the back-flashing can be used as a ""flat" back-flashing e.g. for joins between adjacent ends of cladding material.
As a result, the builder only needs to have a supply of one form of back-f lashing. This can be used in the ""flat" configuration at say a join along a wall of adjacent lengths of cladding profile (see Figure 8) . At an angle or corner of the building construction and around door and window openings, the flashing can be bent into the upright position (relative to the plane of main body 11) so as to provide weatherproofing.
As with known back-flashings, the back-flashing element 10 has a centrally disposed pair of opposing fins 14. Toward the distal ends of the fins 14 and on opposed faces there are provided a plurality of teeth or serrations in a known manner. Thus, a sealing element which is elongate in form and substantially "T" cross-section with substantially equivalent serrations on the distal end of the stem of the ""T11 shape, can be engaged into the groove formed between the opposing fins 14 so as to anchor the sealing element to the back-flashing element.
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Unlike known back-flashing elements however, the present invention provides for the pair of fins 14 to be discontinuous. As a consequence, along the length of the body 11, there are a series of aligned (end to end) but spaced apart centrally disposed anchoring sections 16. Each anchoring section 16 is formed by a pair of opposed fins 14 defining therebetween a groove or slot 15 to receive the stem of a T shaped exterior sealing element.
Located to one but preferably both sides of the anchoring section, is a partition means in the form of a wall 17. The walls 17 are spaced from, but in one preferred form, aligned to the anchoring section 16.
To further describe the back-flashing, reference will now be made to the cladding profile P with which the back-flashing can be used and a building construction employing the back-flashing element.
Figure 4 shows the profile of a cladding P which is used by us in the construction of buildings and referred to under trade mark Supaclad. Along one long edge of the profile P is a tongue T, while the opposite edge has a receiving profile R. Thus, in a known manner the tongue T of one length of profile P can interengage with the receiving section R of an adjacent and parallel disposed length of profile P.
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Located in the width of the profile P is a longitudinally extending channel C. By comparing the elevation of the back-flashing element as shown in Figure 3 with the profile as shown in Figure 4, it will be observed that the positions of the channel C, the tongue T and the receiving section R, correspond with the spaces between adjacent anchoring sections 15 and walls 17. This can be further observed in Figures 6 and 7.
As a consequence, when the cladding P is located with the back-flashing element 10 (the latter having been fastened to the framing F), the walls 17 locate against or closely adjacent the underside of the profile P between the channel C and the respective receiving section R or tongue T. Thus, at least one support wall 17 supports the cladding profile P, preventing it from ""cupping".
In a ""corner" arrangement it will generally be the case that both support walls 17 and the anchoring section 16 locate and contact with or are closely adjacent the profile P to support it against ""cupping".
As can be seen more clearly in Figure 2, the back-flashing element also includes a radiused bead 19 at the outside edge at the main body 11 and on the free or distal edge of the hinged marginal portion 12.
The present invention thus provides a back-flashing which has a multiplicity of support walls 17 and central fins
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The back-flashing is versatile in use, as it can be used in both flat and angle configurations, thereby overcoming the need for the manufacturer to produce two different configurations of back-flashing to suit flat and angle end use. This also is an advantage to the builder who no longer will need to maintain stocks of two different configurations of back-flashing.
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