GB2294751A

GB2294751A - Minimising the ingress of moisture through a chimney

Info

Publication number: GB2294751A
Application number: GB9522417A
Authority: GB
Inventors: Eugene Edward Finn; Eileen Margaret Finn
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-11-02
Filing date: 1995-11-01
Publication date: 1996-05-08
Also published as: GB9522417D0

Abstract

A device (1) for preventing the ingress of moisture from a chimney (4) to a chimney breast (3) comprises a tray (12) which is located in the chimney (4) adjacent the exit of the chimney (4) from a roof (5). The area of the tray (12) is substantially similar to that of the chimney (4), and side walls (14) and an end wall (15) extend upwardly from the tray (12). Flue accommodating openings (17) are located within the tray (12) for accommodating flues (9) of the chimney (4). A first flashing member (22) extends downwardly from the tray (12) over a first lower portion (24) of the roof (5) for facilitating water run off, while a second flashing member (25) extends downwardly from a second upper portion (26) of the roof (5) to the tray (12) between the end wall (15) and the chimney (4). <IMAGE>

Description

"A method and a device for minimising the ingress of moisture through a chimney The present invention relates to a method and device for minimising the ingress of moisture to a chimney breast from a chimney projecting above the roof of a house or other building. The invention also relates to a chimney with the device located therein, and to a building comprising a chimney with the device located therein.

In the past virtually all houses and buildings were built with chimneys which extend above the roof of the house or building. Indeed, many houses are currently being built with chimneys, this is despite the fact that virtually all houses now are provided with central heating. Because of the extensive use of central heating and the limited use, and in many cases, the complete lack of use of a fire delivering warm flue gases through the chimney, problems can arise due to the ingress of moisture from the chimney projecting above the roof of the house or building. Such moisture penetrates down through the chimney and into the chimney breast. This moisture, in general, leads to the formation of damp patches on the chimney breast and adjacent walls in rooms within the house. This is undesirable and objectionable.In general, this problem did not arise in the past when open fires were the normal form of heating. The passage of relatively warm flue gases from an open fire through the flue or flues of a chimney tended to evaporate the moisture in the chimney before it could penetrate below ceiling level, and in many cases before it penetrated much below roof level of the house or building.

There is therefore a need for a method and a device for minimising the ingress of moisture to a chimney breast from a chimney projecting above the roof of a house or building.

The present invention is directed towards providing such a method and a device. The invention is also directed towards providing a chimney with the device located therein, and a building comprising a chimney with the device located therein.

According to the invention there is provided a method for minimising the ingress of moisture to a chimney breast from a chimney projecting above the roof of a house or building, the method comprising the steps of placing a moisture impervious sheet member transversely across the chimney adjacent the exit of the chimney from the roof for preventing the ingress of moisture from the chimney, the area of the sheet member being substantially similar to the transverse cross-sectional area of the chimney adjacent the sheet member, and the sheet member being provided with one or more flue accommodating openings corresponding to the number of flues in the chimney for accommodating respective flues therethrough.

Preferably, the method further comprises the step of connecting the sheet member to the roof by a flashing means.

In one aspect of the invention the method comprises the step of placing the sheet member in the chimney adjacent an inclined roof.

In another aspect of the invention the flashing means comprises a first flashing means which extends between the sheet member and a first portion of the roof adjacent the sheet member but at a level lower than that of the sheet member for accommodating water run off from the sheet member to the roof and for preventing the passage of water between the chimney and the first portion of the roof. The flashing means may also comprise a second flashing means for extending between the sheet member and a second portion of the roof which is adjacent the sheet member but at a level higher than that of the sheet member for accommodating water run off from the roof to the sheet member and for preventing the passage of water between the chimney and the second portion of the roof.

Preferably, the first and second flashing means are located at opposite ends of the sheet member.

Advantageously, side walls extend between the first and second flashing means on opposite sides of the sheet member, the side walls extending upwardly of the sheet member relative to the chimney. Ideally, an inner wall extends around each flue accommodating opening, each inner wall extending upwardly of the sheet member relative to the chimney.

In one aspect of the invention the sheet member is of sheet metal. Preferably, the sheet metal of the sheet member is of stainless steel.

Advantageously, a keying means is provided on at least one side of the sheet member for keying the sheet member to the chimney, and preferably, a keying means is provided on each side of the sheet member.

In a further aspect of the invention each flashing means is of sheet lead material.

Additionally the invention provides a device for minimising the ingress of moisture to a chimney breast from a chimney projecting above the roof of a house or building, the device comprising a sheet member of moisture impervious material for placing transversely across the chimney adjacent the exit of the chimney from the roof for preventing the ingress of moisture through the chimney, the sheet member being of area substantially similar to the transverse cross-sectional area of the chimney adjacent where the sheet member is to be placed, one or more flue accommodating openings being provided in the sheet member for accommodating respective flues therethrough. Preferably, the sheet member defines a peripheral edge for substantially coinciding with the periphery of the chimney.

In one aspect of the invention a flashing means is provided for connecting the sheet member to the roof.

In another aspect of the invention the device is for placing in a chimney adjacent an inclined roof.

In one aspect of the invention the flashing means comprises a first flashing means extending from the sheet member for sealably connecting the sheet member to a first portion of the roof at a level lower than the level of the sheet member for facilitating water run off from the sheet member to the first portion of the roof and for preventing the ingress of moisture between the chimney and the first portion of the roof.

The flashing means may also comprise a second flashing means extending from the sheet member for seal ably connecting the sheet member to a second portion of the roof at a level above that of the sheet member for accommodating water run off from the second portion of the roof to the sheet member and for preventing the ingress of moisture between the chimney and the second portion of the roof.

In one aspect of the invention each flashing means comprises a flashing member, and the first flashing member is connected to the sheet member by folding the flashing member with a portion of the sheet member extending beyond the peripheral edge thereof.

In another aspect of the invention the first and second flashing means are located on respective opposite ends of the sheet member.

Preferably, a pair of side walls extend upwardly from respective opposite sides of the sheet member between the first and second flashing means. Advantageously, an inner wall extends upwardly around each flue accommodating opening.

In one aspect of the invention a keying means is provided on at least one major surface of the sheet member for keying the sheet member to the chimney, and preferably, a keying means is provided on both major surfaces of the sheet member.

Further the invention provides a chimney comprising the device according to the invention, the device being located in and extending transversely across the chimney adjacent the exit of the chimney from the roof for preventing the ingress of moisture from the chimney to a chimney breast.

Further the invention provides a building comprising a roof and a chimney according to the invention.

The invention will be more clearly understood from the following description of a preferred embodiment thereof which is given by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a top perspective view of a device according to the invention for minimising the ingress of moisture to a chimney breast from a chimney, Fig. 2 is a partly cut away side elevational view of a chimney according to the invention with the device of Fig. 1 illustrated installed in a chimney, Fig. 3 is a perspective view of a chimney extending through portion of a roof illustrating the device of Fig. 1 in use, and Fig. 4 is a transverse cross-sectional view of a detail of the device of Fig. 1.

Referring to the drawings there is illustrated a device according to the invention indicated generally by the reference numeral 1 for minimising the ingress of moisture to a chimney breast 3 from a chimney 4 which projects above and through an inclined roof S of a house or building, only a portion 6 of the house being illustrated in Fig. 2. The chimney 4 is of the type which is of rectangular transverse cross-section and is topped with a coping stone 7. The chimney 4 accommodates a pair of flues 9.

The device 1 comprises a sheet member 10 of stainless steel material for placing transversely in the chimney 4 between two courses of bricks or blocks of the chimney 4, adjacent where the chimney 4 exits through the roof 5. The sheet member 10 is bent on opposite sides at 11 to form a tray 12 with short side walls 14 which extend upwardly on two sides of the chimney 4. A short end wall 15 extends upwardly from the sheet member 10 between the side walls 14 for a purpose which will be described below. An end portion 16 extends from the opposite end of the sheet member 10, also for a purpose which will be described below. A pair of flue accommodating openings 17 for accommodating the flues 9 are provided in the tray 12, and inner walls 18 extend around the flue accommodating openings 17, and upwardly from the tray 12 for surrounding the flues 11.

The device 1 is for installing in the chimney 4 adjacent the exit of the chimney 4 through the roof 5, and the area of the tray 12 is substantially similar to the transverse cross-sectional area of the chimney 4 adjacent where the device 1 is to be located. When installed in the chimney 4, the periphery of the tray 12 coincides with the peripheral surface of the chimney 4 and the side walls 14 and end wall 15 project upwardly adjacent the sides and end of the chimney 4, respectively. A keying means, namely, sheets of galvanised expanded metal mesh 20 are welded to the opposite faces of the tray 12 for keying the tray 12 to the chimney 4.

A flashing means comprises a first flashing member 22 and a second flashing member 25 both of sheet lead for preventing the ingress of moisture between the chimney 4 and respective first and second portions 24 and 26, respectively, of the roof 5. The first flashing member 22 is secured to the end portion 16 by folding the flashing member 22 and the end portion 16 together, see Figs. 2 and 4. The first flashing member 22 extends downwardly from the tray 12 and is of sufficient width and length to extend to and over the first portion 24 of the roof S which is at a lower level than the level of the tray 12 in the chimney 4 for facilitating water run off from the tray 12 to the lower first portion 24 of the roof 5.The second flashing member 25 extends from the second portion 26 of the roof 5 which is at a higher level than the level of the tray 12 in the chimney 4, and extends downwardly from the second portion 26 of the roof 5 onto the tray 12 for facilitating water run off from the second portion 26 of the roof 5 onto the tray 12. The second flashing member 25 extends substantially the width of the chimney 4, and extends downwardly into the tray 12 between the end wall 15 and the chimney 4. This, thus, prevents the ingress of moisture between the chimney 4 and the second portion 26 of the roof 5. The first flashing member 22 extends for a width which is substantially similar to the width of the chimney 4, and thus, prevents the ingress of moisture between the chimney 4 and the first portion 24 of the roof 5.

In use, when the chimney 4 has been built to the level of the roof 5, the tray 12 is installed in the chimney 4 with the side and end walls 14 and 15 extending upwardly. A narrow gap is left between the end wall 15 and the chimney 4 for accommodating the second flashing member 25 therebetween. The end portion 16 and the first flashing member 25 are allowed to depend downwardly from the chimney 4. The chimney 4 is then built upwardly from the tray 12 and finished. As the roof is being tiled or slated, the first and second flashing members 22 and 25, respectively, are worked in with the roof cladding at the appropriate times.

The advantages of the invention are many, a particularly important advantage of the invention is that the ingress of moisture from the chimney to the chimney breast is almost entirely eliminated, and in most cases, is completely eliminated. The tray acts as a moisture barrier thereby preventing the ingress of moisture from the chimney to the chimney breast.

While the device has been described for use in a chimney having two flues, the device may be provided for a chimney with one, or indeed, any number of flues.

While it is preferable, it is not essential that the side walls and end wall be provided. Indeed, the inner walls may also be omitted. It is also envisaged that the keying means may be omitted, and where a keying means is provided, any other suitable keying means besides galvanised expanded metal mesh may be provided.

It will of course be appreciated that sheet materials other than sheet lead and sheet stainless steel may be used in the construction of the device.

Claims

1. A method for minimising the ingress of moisture to a chimney breast from a chimney projecting above the roof of a house or building, the method comprising the steps of placing a moisture impervious sheet member transversely across the chimney adjacent the exit of the chimney from the roof for preventing the ingress of moisture from the chimney, the area of the sheet member being substantially similar to the transverse crosssectional area of the chimney adjacent the sheet member, and the sheet member being provided with one or more flue accommodating openings corresponding to the number of flues in the chimney for accommodating respective flues therethrough.

2. A method as claimed in Claim 1 in which the method further comprises the step of connecting the sheet member to the roof by a flashing means.

3. A method as claimed in Claim 2 in which the method comprises the step of placing the sheet member in the chimney adjacent an inclined roof.

4. A method as claimed in Claim 3 in which the flashing means comprises a first flashing means which extends between the sheet member and a first portion of the roof adjacent the sheet member but at a level lower than that of the sheet member for accommodating water run off from the sheet member to the roof and for preventing the passage of water between the chimney and the first portion of the roof.

5. A method as claimed in Claim 3 or 4 in which the flashing means comprises a second flashing means which extends between the sheet member and a second portion of the roof which is adjacent the sheet member but at a level higher than that of the sheet member for accommodating water run off from the roof to the sheet member and for preventing the passage of water between the chimney and the second portion of the roof.

6. A method as claimed in Claim 5 in which the first and second flashing means are located at opposite ends of the sheet member.

7. A method as claimed in Claim 5 or 6 in which side walls extend between the first and second flashing means on opposite sides of the sheet member, the side walls extending upwardly of the sheet member relative to the chimney.

8. A method as claimed in any preceding claim in which an inner wall extends around each flue accommodating opening, each inner wall extending upwardly of the sheet member relative to the chimney.

9. A method as claimed in any preceding claim in which the sheet member is of sheet metal.

10. A method as claimed in Claim 9 in which the sheet metal of the sheet member is of stainless steel.

11. A method as claimed in any preceding claim in which a keying means is provided on at least one side of the sheet member for keying the sheet member to the chimney.

12. A method as claimed in Claim 11 in which a keying means is provided on each side of the sheet member.

13. A method as claimed in any of Claims 2 to 12 when dependent on Claim 2 in which each flashing means is of sheet lead material.

14. A method for minimising the ingress of moisture to a chimney breast from a chimney projecting above the roof of a house or building, the method being substantially as described herein with reference to and as illustrated in the accompanying drawings.

15. A device for minimising the ingress of moisture to a chimney breast from a chimney projecting above the roof of a house or building, the device comprising a sheet member of moisture impervious material for placing transversely across the chimney adjacent the exit of the chimney from the roof for preventing the ingress of moisture through the chimney, the sheet member being of area substantially similar to the transverse cross-sectional area of the chimney adjacent where the sheet member is to be placed, one or more flue accommodating openings being provided in the sheet member for accommodating respective flues therethrough.

16. A device as claimed in Claim 15 in which the sheet member defines a peripheral edge for substantially coinciding with the periphery of the chimney.

17. A device as claimed in Claim 15 or 16 in which a flashing means is provided for connecting the sheet member to the roof.

18. A device as claimed in Claim 17 in which the device is for placing in a chimney adjacent an inclined roof.

19. A device as claimed in Claim 18 in which the flashing means comprises a first flashing means extending from the sheet member for sealably connecting the sheet member to a first portion of the roof at a level lower than the level of the sheet member for facilitating water run off from the sheet member to the first portion of the roof and for preventing the ingress of moisture between the chimney and the first portion of the roof.

20. A device as claimed in Claim 18 or 19 in which the flashing means comprises a second flashing means extending from the sheet member for sealably connecting the sheet member to a second portion of the roof at a level above that of the sheet member for accommodating water run off from the second portion of the roof to the sheet member and for preventing the ingress of moisture between the chimney and the second portion of the roof.

21. A device as claimed in any of Claims 19 to 20 in which each flashing means comprises a flashing member, and the first flashing member is connected to the sheet member by folding the flashing member with a portion of the sheet member extending beyond the peripheral edge thereof.

22. A device as claimed in any of Claims 19 to 21 in which the first and second flashing means are located on respective opposite ends of the sheet member.

23. A device as claimed in any of Claims 19 to 22 in which a pair of side walls extend upwardly from respective opposite sides of the sheet member between the first and second flashing means.

24. A device as claimed in any of Claims 15 to 23 in which an inner wall extends upwardly around each flue accommodating opening.

25. A device as claimed in any of Claims 15 to 24 in which a keying means is provided on at least one major surface of the sheet member for keying the sheet member to the chimney.

26. A device as claimed in Claim 25 in which a keying means is provided on both major surfaces of the sheet member.

27. A device for minimising the ingress of moisture to a chimney breast from a chimney projecting from the roof of a house or building, the device being substantially as described herein with reference to and as illustrated in the accompanying drawings.

28. A chimney comprising the device as claimed in any of Claims 15 to 27 in which the device is located in and extends transversely across the chimney adjacent the exit of the chimney from the roof for preventing the ingress of moisture from the chimney to a chimney breast.

29. A chimney as claimed in Claim 28 in which the device is placed in the chimney for preventing the ingress of moisture to a chimney breast of the chimney, the device being placed in the chimney using the method according to any of Claims 1 to 14.

30. A chimney substantially as described herein with reference to and as illustrated in the accompanying drawings.

31. A building comprising a roof and a chimney as claimed in any of Claims 28 to 30 extending through the roof.