IE20020283A1

IE20020283A1 - Gutter expansion joint

Info

Publication number: IE20020283A1
Application number: IE20020283A
Authority: IE
Inventors: Brian Mcintyre; Robert Rae
Original assignee: Cgl Cometec Ltd
Priority date: 2001-04-18
Filing date: 2002-04-18
Publication date: 2002-10-30
Also published as: GB2375360B; GB2375360A; GB0208726D0; GB0109516D0

Abstract

The present invention provides an expansion joint arrangement for guttering. The joint is comprised of abutting first and second gutters 3,5 23,25 which are secured to one another by a structural sealant adhesive 8,28. The sealant adhesive 8, 28 is a modified silicon sealant that is sufficiently strong as to provide a watertight expansion joint without the need for mechanical fixings. The joint itself may be a joggle joint or else may be a butt strap arrangement. <Figure5>

Description

GUTTER EXPANSION JOINT The present invention relates to an expansion joint and in particular to an expansion joint for guttering that remains watertight under thermal or mechanical expansion of the joint.

Gutter expansion joints are used so that guttering remains watertight when subject to strain. A traditional technique for joining gutter sections relies on the use of a joggle joint or butt strap with a sealant applied between the sections. Once the sealant is applied, the sections are fixed by bolts or similar mechanical fixing means. The employment of such fixing means has the obvious disadvantage that holes are required to be punched through the section pieces, and the holes themselves can become the source of leaks and, in metal sections, a source of metal fatigue or corrosion.

OPEN TO PUBLIC INSPECTION UNDER SECTION 28 AND RULE 25 iNl No. Of S g U A more recent alternative to the above technique involves the use of butt straps. Butt straps are attached across an expansion gap between any two sections. Placed over the top of the butt strap is a membrane that can then be solvent or heat welded in place to provide the water tight expandable joint. Although providing a significant improvement in terms of reliability over the previous methods, the use of butt straps is still time consuming, relying on solvent or heat welding to be carried out. Accordingly the formation of such systems tends to be carried out at the factory before being transported to the required location.

It is an aim of the present invention to obviate or mitigate one or more of the problems described above .

According to a first aspect of the present invention, there is provided a gutter expansion joint comprising first and second gutter sections, the first gutter section having an abutting portion which abuts a corresponding abutting portion on the second gutter section, wherein at least one of the abutting portions has an adhesive sealant applied thereto such that the first and second gutter sections are fixed together by said adhesive sealant.

In a preferred embodiment, the abutting portion of the first gutter section comprises a joggle portion, and the abutting portion of the second gutter section comprises a projecting shelf, wherein the adhesive sealant is applied to the joggle portion such that the shelf is adhered thereto.

Preferably, the joggle portion has barrier means for retaining the adhesive sealant thereon. Preferably, the barrier means comprises a stopper fixed to the joggle portion. Alternatively, the barrier means comprises one or more shaped troughs.

In a second preferred embodiment, both abutting portions have adhesive sealant applied thereto, the joint further comprising a butt strap positioned over the joint and fixed to the abutting portions of the first and second gutter sections by the adhesive sealant.

Preferably, one of the first and second gutter sections has a projecting flange extending at least partially around the outer perimeter of the abutting portion of the gutter section, the outer surface of the other gutter section adjacent the abutting portion being positioned on said flange.

The adhesive sealant is a modified silicon structural sealant having a breaking strength greater than lN/mm2 and preferably greater than. 2N/mm2 .

Preferably, the adhesive sealant has a maximum allowed distortion of ±25%. Preferably, the adhesive sealant also has a modulus of elasticity in IEO 2 0 2 8 3 the range 0.5-1.5N/mm2 and most preferably in the range 0.75-1.5N/mm2.

According to a second aspect of the present invention, there is provided a method of forming a gutter expansion joint from first and second gutter sections, the first gutter section having an abutting portion adapted to abut a corresponding abutting portion on the second gutter section, the method comprising the steps of: applying an adhesive sealant to at least one of the abutting portions; and positioning the first and second gutter sections such that the abutting portion of the first gutter section abuts the corresponding abutting portion of the second gutter section such that the first and second gutter sections are fixed together by said adhesive sealant.

Preferably, the method comprises the further step of adapting the joggle portion to provide a barrier means for retaining the adhesive sealant on the joggle section. Preferably, said barrier means comprises a stopper fixed to the joggle portion.

IE 0 Ζ 0 2 8 3 Alternatively, said barrier means comprises one or more shaped troughs .

Preferably, the method further comprises a further step of applying an additional quantity of adhesive sealant between the joggle section and shelf following the positioning step.

In a second preferred embodiment, the adhesive sealant is applied to the abutting portions of both the first and second gutter sections by way of an adhesive sealant-coated butt strap adapted to be fixed to the first and second gutter sections.

Preferably, one of the first or second gutter sections has a projecting flange extending at least partially around the outer perimeter of the abutting portion of the gutter section, the outer surface of the other gutter section adjacent the abutting portion being positioned on said flange during the positioning step.

Preferably, the adhesive sealant is a modified silicon structural sealant having a breaking strength greater than lN/mm2 and most preferably greater than 2N/mm2.

Preferably, the adhesive sealant has a maximum allowed distortion of ±25%. Preferably, the adhesive sealant has a modulus of elasticity in the range 0.5-1.5N/mm2 and most preferably in the range 0.75-1.5N/mm2.

IE 0 2 0 2 8 3 An embodiment of the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a section view through a first embodiment of a gutter expansion joint; Figures 2(a)-(c) show the steps of a method of constructing the expansion joint of Figure 1; Figure 3 shows a section view through a second embodiment of the gutter expansion joint; Figures 4(a)-(d) show the steps of a method of constructing the expansion joint of Figure 3; Figure 5 shows a section view through a third embodiment of the gutter expansion joint; and Figures 6(a)-(d) show the steps of a method of constructing the expansion joint of Figure 5.

Referring initially to Figure 1, a first embodiment of an expansion joint for joining sections of an insulated modular gutter is generally depicted at 1. The view shown is a section view through the base of the gutter sections, with the remaining portions of the gutter removed for illustrative purposes. The expansion joint 1 comprises first and second gutter sections 3,5 which each have an abutting portion which abuts the corresponding abutting portion of the other gutter section. In this first embodiment, the abutting portion of the first gutter section 3 is a joggle portion 2, and the abutting portion of the second gutter section 5 is a projecting shelf 4.

The joggle portion 2 is formed by an indentation or notch in the first gutter section 3 which contains two generally U-shaped troughs 6 and 7. These Ushaped troughs 6 and 7 are employed to house a structural adhesive sealant 8 that acts to bond the gutter sections 3 and 5 together while producing a watertight seal between them. The dimensions of the U-shaped troughs 6 and 7 are chosen such that the structural adhesive sealant 8 is maintained at an optimum thickness so as produce the adhesive, watertight and expansion properties required for the expansion joint 1.

Figures 2(a)-(c) present the three steps required to form the first embodiment of the gutter expansion joint joining the first and second gutter sections 3,5 together. These steps involve: 1. a first quantity of structural adhesive sealant 8 being applied to fill the second U-shaped trough 7 of the joggle portion 2 of the first gutter section 3, as depicted in Figure 2(a); the second gutter section 5 then being positioned so as to abut the first gutter section 3, such that the shelf 4 of the second gutter section 5 locates across the top of the joggle portion 2 of the first gutter section 3 thereby contacting the adhesive sealent 8 in the trough 7, as depicted in Figure 2(b); and 3. a second quantity of structural adhesive sealant 8 then being applied at the interface of the shelf 4 of the second gutter section 5 and an edge portion of the first U-shaped trough 6 of the first gutter section 3, as depicted in Figure 2(c).

Figures 3 and 4(a)-(d) show a modified embodiment of the gutter expansion joint described above. Again, the view shown is a section view through the base of the gutter sections, with the remaining portions of the gutter removed for illustrative purposes. The modified expansion joint 10 comprises first and second insulated modular gutter sections 13,15. As before, the first gutter 13 is provided with an abutting portion in the form of a joggle portion 12 while the second gutter 15 has an abutting portion in the form of a shelf 14.

Where this embodiment differs from the first embodiment is that in place of the trough arrangement on the joggle portion 12 there is a plastic stopper 16 located at the leading edge of the joggle portion 12 of the first gutter 13. The stopper 16 retains the structural adhesive sealant 18 in the joggle portion 12 such that the first and second gutters may be bonded together to produce a watertight expansion joint.

Figures 4(a)-(d) show the steps to achieving the expansion joint of the second embodiment. The steps involve: e 1. applying the stopper 16 at the leading edge of a joggle portion 12 of the first gutter section 13 to retain the adhesive sealant 18, as depicted in Figure 4(b); 2. applying a quantity of adhesive sealant 18 to fill the joggle portion 12 of the first gutter 13, as depicted in Figure 4(c); 3. positioning the second gutter 15 so as to abut the first gutter 13, such that the shelf 14 of the second gutter 15 locates across the top of the joggle portion 12 of the first gutter 13 and contacts the adhesive sealant 18 in the joggle portion 12, as depicted in Figure 4(d).

Figures 5 and 6(a)-(d) show a third embodiment of the gutter expansion joint. As with the previously described embodiments, the view shown is a section view through the base of the gutter sections, with the remaining portions of the gutter removed for illustrative purposes. The expansion joint 20 comprises first and second gutter sections 23,25, but unlike the previously described embodiments, neither the first or second gutters 23,25 has a joggle portion. Instead, this embodiment utilises an adapted butt strap arrangement. ΙΕΟ 2 028 3 The joint is formed between the abutting first and second gutters 23,25 by applying the adhesive sealant 28 to a butt strap 30 which is then positioned so as to be across the join of the abutting gutters 23,25. Adhesive tape 27 is placed across the join prior to the application of the butt strap 30.to prevent ingress of adhesive sealant 28 into the join. The second gutter 25 has a flange 24 upon which the first gutter is positioned to facilitate the creation of the joint.

With reference to Figures 6(a)-(d), the method steps of achieving the third embodiment of the gutter expansion joint are shown. The steps comprise: 1. Positioning the first gutter 23 upon the flange 24 of the second gutter 25 such that an abutting portion of the second gutter 25 abuts a corresponding abutting portion of the first gutter 23, as depicted in Figure 6(a); 2. applying an adhesive tape 27 across the join of the abutting gutters 23,25 so as to prevent sealant adhesive from entering the join between the gutters 23,25, as depicted in Figure 6(b); 3. affixing plastic stoppers 26 to each end of a butt strap 30, and inverting the butt strap 30 so as to apply a quantity of adhesive sealant 28 to the underside of the butt strap 30, as depicted in Figure 6(c); and 4. righting the butt strap arrangement and affixing it to the abutting portions of the first and second gutters 23,25 so that the butt strap 30 is positioned over the join of the abutting first and second gutters 23,25 and adhesive tape 27, as depicted in Figure 6(d).

In this way, a watertight expansion joint is produced without the need to apply mechanical fixings to either of the first and second gutters.

A suitable structural adhesive sealant for use in each of the embodiments described above is a modified silicon sealant, based upon MS Polymer.

The sealant has a breaking strength greater than lN/mm2 and preferably greater than 2N/mm2. In tests, it has been found that the sealant may optimally have a breaking strength of 2.2N/mm2. Furthermore, the sealant may distort by up to ±25%. In other words, the sealant may expand or contract by up to 25% without any breakage or adverse effects upon its performance. To permit this distortion, the sealant has a modulus of elasticity of between 0.5N/mm2 and 1.5N/mm2. Tests have shown that a modulus of elasticity of between 0.75N/mm2 and 1.5N/mm2 is preferable, and that a modulus of elasticity of 1.3N/mm2 is best for this application. Additionally, the structural adhesive sealant is temperature resistant between -40°C and +90°C.

The adhesive sealant is resistant to water and, thanks to the properties discussed above, it can flex and expand when placed under stress or strain to maintain the joint. This is in contrast to sealants currently used in this field which are' not intended to offer adhesive properties because mechanical fixings secure the gutter components together.

When applied, the structural adhesive sealant maintains contact with the gutters at all times so rendering the expansion joint watertight. Ideally, a surface activator is applied to the surface initially to remove any moisture, grease or the like from the surface. This ensures a good initial contact between the sealant adhesive and the gutters .

The structural adhesive sealant exhibits a reliable tensile strength that is capable of pulling down the unloaded section of the gutter adjacent to the expansion joint. It offers a high initial tack thus removing the requirement for initial support when applied to the expansion joint.

The present invention has the advantage that it provides a reliable and quickly-assembled watertight expansion joint that does not require the employment of mechanical fixings, and can be easily assembled on site. The adhesive sealant used has a combination of strength and elasticity superior to conventional sealants. This allows the adhesive sealant to be used for the joint where the conventional sealants would be unsuitable.

Modifications and improvements may be incorporated without departing from the scope of the invention.

Claims

CLAIMS:

1. A gutter expansion joint comprising first and second gutter sections, the first gutter section having an abutting portion which abuts a corresponding abutting portion on the second gutter section, wherein at least one of the abutting portions has an adhesive sealant applied thereto such that the first and second gutter sections are fixed together by said adhesive sealant.

2. The expansion joint of Claim 1, wherein the abutting portion of the first gutter section comprises a joggle portion, and the abutting portion of the second gutter section comprises a projecting shelf, wherein the adhesive sealant is applied to the joggle portion such that the shelf is adhered thereto.

3. The expansion joint of Claim 2, wherein the joggle portion has barrier means for retaining the adhesive sealant thereon.

4. The expansion joint of Claim 3, wherein the barrier means comprises a stopper fixed to the joggle portion.

5. The expansion joint of Claim 3, wherein the barrier means comprises one or more shaped troughs .

6. The expansion joint of Claim 1, wherein both abutting portions have adhesive sealant applied thereto, the joint further comprising a butt strap positioned over the joint and fixed to the abutting portions of the first and second gutter sections by the adhesive sealant.

7. The expansion joint of any preceding claim, wherein one of the first and second gutter sections has a projecting flange extending at least partially around the outer perimeter of the abutting portion of the gutter section, the outer surface of the other gutter section adjacent the abutting portion being positioned on said flange.

8. The expansion joint of any preceding claim, wherein the adhesive sealant is a modified silicon structural sealant.

9. The expansion joint of any preceding claim, wherein the adhesive sealant has a breaking strength greater than lN/mm 2 .

10. The expansion joint of any preceding claim, wherein the adhesive sealant has a breaking strength greater than 2N/mm 2 .

11. The expansion joint of any preceding claim, wherein the adhesive sealant has a maximum allowed distortion of ±25%.

12. The expansion joint of any preceding claim, wherein the adhesive sealant has a modulus of elasticity in the range 0.5-1.5N/mm 2 .

13. The expansion joint of any preceding claim, wherein the sealant has a modulus of elasticity in the range 0.75-1.5N/mm 2 .

14. A method of forming a gutter expansion joint from first and second gutter sections, the first gutter section having an abutting portion adapted to abut a corresponding abutting portion on the second gutter section, the method comprising the steps of: applying an adhesive sealant to at least one of the abutting portions; and positioning the first and second gutter sections such that the abutting portion of the first gutter section abuts the corresponding abutting portion of the second gutter section such that the first and second gutter sections are fixed together by said adhesive sealant.

15. The method of Claim 14, wherein the abutting portion of the first gutter section comprises a joggle portion, and the abutting portion of the second gutter section comprises a projecting shelf, wherein the adhesive sealant is applied to the joggle portion such that the shelf is adhered thereto .

16. The method of Claim 15, comprising the further step of adapting the joggle portion to provide a barrier means for retaining the adhesive sealant on the joggle section.

17. The method of Claim 16, wherein said barrier means comprises a stopper fixed to the joggle portion.

18. The method of Claim 16, wherein said barrier means comprises one or more shaped troughs.

19. The method of any of Claims 15 to 18, further comprising the step of applying an additional quantity of adhesive sealant between the joggle section and shelf following the positioning step .

20. The method of Claim 14, wherein the adhesive . sealant is applied to the abutting portions of both the first and second gutter sections by way of an adhesive sealant-coated butt strap adapted to be fixed to the first and second gutter sections .

21. The method of either of Claims 14 or 20, wherein one of the first or second gutter sections has a projecting flange extending at least partially around the outer perimeter of the abutting portion of the gutter section, the outer surface of the other gutter section S 28 3 adjacent the abutting portion being positioned on said flange during the positioning step.

22. The method of any of Claims 14 to 21, wherein the adhesive sealant is a modified silicon structural sealant.

23. The method of any of Claims 14 to 22, wherein the adhesive sealant has a breaking strength greater than lN/mm 2 .

24. The method of any of Claims 14 to 23, wherein the adhesive sealant has a breaking strength greater than 2N/mm 2 .

25. The method of any of Claims 14 to 24, wherein the adhesive sealant has a maximum allowed distortion of ±25%.

26. The method of any of Claims 14 to 25, wherein the adhesive sealant has a modulus of elasticity in the range 0.5-1.5N/mm 2 .

27. The method of any of Claims 14 to 26, wherein the adhesive sealant has a modulus of elasticity in the range 0.75-1.5N/mm 2 .

28. A gutter expansion joint substantially as hereinbefore described with reference to the accompanying drawings . IE Ο 2 9 2 8 3 1 29. A method of forming a gutter expansion joint substantially as hereinbefore described with reference to the accompanying drawings.