Field of the Invention
[0001] This invention concerns a chimney attachment and method of fitting a flue liner in
a chimney.
Background
[0002] Many existing chimneys can be repaired or improved by installing a flue liner which
is effectively an inner tube for the chimney. A chimney is usually lined by passing
a flexible metal tube along the length of the chimney and the liner is usually supported
at the top of the chimney by a top support plate. A chimney pot is usually fitted
to the chimney top to protect the flue liner and provide a traditional finish to the
chimney top.
[0003] Providing a waterproof seal at the top of the chimney has always been a problem and
installers often do not achieve a seal that will last the life of the installation.
Masonry chimneys are usually porous and moisture may be driven through a brick or
stone chimney by capillary action. Moisture entering the space between the liner and
the chimney may interact with old soot, sulphurous material and other debris contained
in the space to produce an unpleasant smell. Since the inside of the chimney will
get hot in use (due to the passage of hot flue gases) the moisture in the space may
form malodorous fumes. If there is no other vent for such fumes then the fumes may
enter the house via the chimney (for example through the bricks or mortar. The fumes
may comprise, for example, gases, water vapour and particulate matter (such as soot
or other debris), and the term "fumes" should be taken to be any matter that can be
vented.
[0004] Although it is advisable to ventilate the space outside a flue liner it is common
that no provision for ventilation is made. Air bricks or ventilation pipes are sometimes
provided however it is questionable which side of the chimney is the most suitable
position for such bricks depending on the wind direction relative to the chimney.
Also flue installers/fitters may neglect to fit such bricks or pipes because, for
example, of inclement weather conditions and exposure on the roof of the house. That
is, a worker on a ladder, in the rain, may not be minded to drill holes in the chimney
brickwork that would be necessary to provide appropriate ventilation.
Summary of the invention
[0005] According to an aspect of the invention there is provided a chimney attachment for
fitting to a chimney to support a flue liner in the chimney, the flue liner and chimney
defining a space therebetween. The chimney attachment may comprise a support for supporting
the flue liner in the chimney. The chimney attachment may be arranged such that connection
of the flue liner to the support provides a first outlet in gaseous communication
with the flue liner for venting flue gases to atmosphere and a second outlet in gaseous
communication with the space between the flue liner and the chimney to vent gases
(e.g. water vapour) in the space to atmosphere.
[0006] Conveniently, the flue liner may comprise a flexible metal flue liner. For instance,
the flue liner may be constructed from stainless steel.
[0007] Preferably, the attachment may constitute, in use, a primary support for the flue
liner within the chimney. In use, the attachment may bear substantially the full weight
of the flue liner. Advantageously, the attachment may constitute, in use, the only
support for the flue liner within the chimney, i.e. the flue liner may not be attached
or connected to the wall of the chimney by any other means at any other point. Preferably,
the attachment may be attached to a top end of the flue liner. In use, the flue liner
may hang or be suspended from the attachment. Preferably, the support may be adapted
to engage with the flue liner at or close to a top end of the flue liner.
[0008] The chimney attachment may be advantageous as on fitting the chimney attachment to
a chimney and/or chimney pot and connecting a flue liner to the chimney attachment
a vent (second outlet) is provided for fumes that may be present between the flue
liner and the chimney. Since the vent is effectively built into the chimney attachment
there is no need to rely on a worker to drill holes or fit air bricks in the masonry
of the chimney, it is a natural consequence of fitting the chimney attachment.
[0009] In one embodiment, the first and second outlets are a common outlet, the chimney
attachment comprising flue gas and ventilation flow channels, each leading to the
common outlet, the flue gas flow channel in gaseous communication with the flue liner
and the ventilation flow channel in communication with the space between the flue
liner and the chimney. Such a common outlet may allow an aesthetically pleasing chimney
attachment to be formed without parts of the attachment extending beyond the radial
width of the chimney.
[0010] In another embodiment, the first and second outlets are separate outlets. For example,
the chimney attachment may comprise a wall defining a flue gas flow path terminating
in the first outlet, the wall providing a support surface to which the flue liner
can be connected, connection of the flue liner to the support surface separating the
first outlet from the second outlet. The wall may define a central void, the void
providing the flue gas flow path, and may be arranged to be spaced from a chimney
or chimney pot to provide a ventilation flow path between the wall and the chimney
or chimney pot to the second outlet. The support surface to which the flue liner can
be connected may be arranged to be located downstream of where the wall first divides
a space in a chimney or chimney pot into the flue gas and the ventilation flow paths.
It will be understood that "downstream" and "upstream" as used herein means relative
to the flow of flue gases. It may be desirable to separate the first outlet from the
second outlet to avoid flue gases entering the space between the flue liner and the
chimney and to allow the second outlet to be designed for the specific requirements
for venting the space. For example, it may be desirable that the second outlet is
arranged to avoid the ingress of rain water to the space between the flue liner and
the chimney through the second outlet. More specifically, the attachment may be arranged
such that, in use, the second outlet opens horizontally or/and downwardly.
[0011] In one embodiment, the second outlet may be a hole in the wall, the hole located
upstream of the support surface. For example, the chimney attachment may be a chimney
pot wherein the flue liner is arranged to be connected to the inner surface of the
chimney pot downstream of a hole in the chimney pot that provides the second outlet.
[0012] Alternatively, the chimney attachment is arranged to be retro-fitted to a chimney
pot, (rather than being the chimney pot itself).
[0013] In one arrangement, the chimney attachment comprises a frame attachable to the chimney
or a chimney pot, the frame comprising a support ring providing the support for connecting
to the flue liner, the support ring connectable to the chimney such that there is
a gap between a wall of the chimney and at least a portion of the support ring, the
gap leading to the second outlet to vent gases in the space to atmosphere.
[0014] The second outlet may be provided at at least two, three and preferably four or more
spaced apart locations around the terminal attachment. Preferably, the second outlet
extends continuously around a substantial, and preferably, all of a circumference
of the chimney attachment. It will be understood that "a substantial circumference"
may mean at least a quarter and more preferably, at least a half of the circumference.
This construction of the chimney attachment may mean that the ventilation provided
by the attachment is not directional and provides ventilation in substantially all
radial directions. This provides the advantage that a fitter does not need to consider
wind direction or other factors since the chimney attachment or terminal generally
has no preferred orientation about its longitudinal axis.
[0015] Preferably, the attachment may provide a support surface for chimney-top devices
or ornaments such as rain caps, aerials or weather vanes. Optionally, the attachment
may comprise a rain cap configured to prevent or at least reduce the ingress of rain
into the chimney without obstructing the or each outlet. The rain cap may be provided
with the attachment and attachable thereto. Alternatively, the rain cap may be permanently
connected to or integrally formed with the attachment. The provision of a rain cap
may improve the aesthetic appearance of a given chimney.
[0016] In an embodiment, the attachment may comprise a spacing member and a pot hanger,
wherein, in use, the spacing member is located or locatable on top of a chimney or
a chimney pot and between the chimney or the chimney pot and the pot hanger, wherein
the spacing member is shaped and dimensioned such that, in use, the second outlet
is defined at least partially by the spacing member.
[0017] The second outlet may be defined by the spacing member or by a combination of the
spacing member and the chimney pot or the chimney or by a combination of the spacing
member and the pot hanger.
[0018] The spacing member and the pot hanger may be provided as separate components. Alternatively,
the spacing member and the pot hanger may be integrally formed or permanently joined,
e.g. welded, together.
[0019] The spacing member may comprise a flange or a washer. Preferably, the spacing member
may be made from a metal, e.g. stainless steel.
[0020] The spacing member may comprise a Belleville washer or an at least partially corrugated
washer. A suitable corrugated washer may be manufactured from a flat washer using
a crimping machine.
[0021] According to a further aspect of the invention, there is provided a method of installing
a flue liner into a chimney comprising fitting a chimney attachment onto and/or into
a chimney or a chimney pot and attaching a flue liner to the chimney attachment. The
chimney attachment may comprise at least one outlet. The flue liner may be connected
to the chimney attachment such that the at least one outlet is in gaseous communication
with the flue liner for venting flue gases to atmosphere and in gaseous communication
with the space between the flue liner and the chimney to vent gases in the space to
atmosphere.
[0022] Conveniently, the flue liner may comprise a flexible metal flue liner. For instance,
the flue liner may be constructed from stainless steel.
[0023] Preferably, the attachment may constitute a primary support for the flue liner within
the chimney. The attachment may bear substantially the full weight of the flue liner.
Advantageously, the attachment may constitute the only support for the flue liner
within the chimney, i.e. the flue liner may not be attached or connected to the wall
of the chimney by any other means at any other point. Preferably, the attachment may
be attached to a top end of the flue liner. The flue liner may hang or be suspended
from the attachment.
[0024] At least one outlet may comprise a first outlet and a second outlet, wherein the
flue liner is attached to the chimney attachment such that the first outlet is in
gaseous communication with the flue liner for venting flue gases to atmosphere and
the second outlet is in gaseous communication with the space between the flue liner
and the chimney to vent gases in the space to atmosphere.
[0025] The method may comprise fitting the chimney attachment to the top of a chimney pot.
[0026] The method may comprise not drilling a ventilation hole or fitting ventilation bricks
in a chimney stack of the chimney.
[0027] The method may comprise fitting a rain cap to the chimney attachment. Alternatively,
the chimney attachment may comprise a rain cap.
[0028] According to a further aspect of the invention there is provided, in combination,
a chimney having a flue liner therein and a chimney attachment, the flue liner and
chimney defining a space therebetween, the chimney attachment connected to the flue
liner to provide a first outlet in gaseous communication with the flue liner for venting
flue gases to atmosphere and a second outlet in gaseous communication with the space
between the flue liner and the chimney to vent gases in the space to atmosphere.
[0029] The chimney attachment of the invention can be used with chimneys that may or may
not be provided with a chimney pot. Therefore, references to the chimney attachment
being configured and used in relation to a chimney pot can also be read as being configured
and used in relation to a chimney and vice versa.
[0030] Embodiments of the present invention will now be described, by way of example only,
with reference to the accompanying drawings, in which:-
Figure 1 is a cross-sectional view of a chimney finished with a flue liner presented
as background to the invention;
Figure 2 is a cross-sectional view of a chimney finished with a flue liner and a "pot
hanger" presented as background to the invention;
Figure 3 is a cross-sectional view of a chimney finished with a flue liner and a chimney
attachment according to an embodiment of the invention;
Figure 4 is a cross-sectional view of a chimney attachment with the chimney attachment
in-situ at the end of a chimney according to an embodiment of the invention;
Figure 5 is an oblique view of the chimney attachment of Figure 4 with the line A-A
corresponding to the section illustrated in Figure 4;
Figure 6 is a cross-sectional view of a chimney attachment according to another embodiment
of the invention;
Figure 7 is a cross-sectional view of part of a chimney attachment according to another
embodiment of the invention;
Figure 8 is a cross-sectional view of part of a chimney attachment according to a
further embodiment of the invention; and
Figure 9 illustrates a cross-sectional view of a further embodiment of a chimney attachment
according to an embodiment of the invention.
[0031] Referring to Figure 1, a chimney 30 is provided with a flue liner 10 and a chimney
pot 20. It is normal practice to take the liner 10 to the top of the chimney pot 20.
The space between the liner 10 and the chimney 30 may be loose filled with a material
such as Vermiculite or perlite insulation. Typically the liner 10 is a flexible metal
liner, for example, the liner may be constructed from stainless steel. Providing a
seal between the chimney pot 20 and the liner 10 can be problematic. Usually the seal
is provided by hard cement mortar, however, this generally does not seal well with
a metal liners because such liners expand and contract as they heat up and cool down.
Flexible sealants may be used but these usually do not tolerate the high temperatures
present when the chimney is in operation and these sealants can degrade.
[0032] Figure 2 illustrates a similar chimney and liner system to that shown in Figure 1
but in this case a conventional seal 40 is present to provide a seal between the liner
10 and pot 20 (such seals 40 are often referred to as "pot-hanger" seals). In this
case, a flexible sealant 42 can be used to prevent rain entering the chimney between
the liner 10 and the pot 20. A vent 50 may be provided in the chimney 30 by the fitment
of an air brick ventilation component or by the drilling of holes, according to the
practice of the tradesperson installing the pot-hanger seal 40.
[0033] Figure 3 illustrates a chimney and liner system which has been provided with a chimney
attachment 100 in accordance with one particular embodiment of the invention. The
chimney attachment 100 provides a first, central outlet 114 for venting flue gases
that travel up flue liner 10 and a channel 110 for venting fumes from the space 15
between the flue liner 10 and the chimney pot 20 through a second outlet 112. That
is, the chimney attachment 100 defines a conduit that provides flow communication
from the space 15 between the flue liner 10 and the wall of the chimney pot 20 to
the second outlet 112. The curved arrows shown in Figure 3 illustrate the flow of
gases vented from the space 15. It can be seen that the fumes are vented away from
the opening of the flue so that the fumes do not travel down the flue into the building.
[0034] Figure 4 is a cross-sectional view of the chimney attachment 100 fitted to the top
of a flue. The chimney attachment 100 is a frame comprising an outer wall 140 and
an inner wall 150. These walls 140, 150 at least in part, define a ventilation channel
110 that acts as a vent for fumes from the space 15 or region/volume that is present
between the chimney/chimney pot 20 and the flue liner 10. In effect the channel 110
provides flow communication between the space 15 outside the flue liner 10 to the
outside wall of the chimney/chimney pot 20 thereby directing fumes away from the inside
of the flue. The flow of the fumes is illustrated by curly arrows in Figure 4.
[0035] It should be noted that a chimney pot may or may not be provided on the chimney so
that the chimney attachment 100 can vent to the outside of a chimney pot (if present)
or to the outside of the chimney itself.
[0036] In the embodiment of the chimney attachment 100 illustrated in Figure 4 there is
a top wall 120 that joins with the inner 150 and outer walls 140 to form an open box
section that provides the venting channel 110. A further radial inner wall 145 having
an L-section defines the radial inner extent of the ventilation channel 110. This
radial inner wall may be attached to the walls 140, 150, by appropriate bridges (not
shown), the bridges having gaps therein to allow fumes to flow to the outlet 112.
As will be discussed in reference to Figures 6-7, various geometries can be used to
provide a venting channel 110 of which some do not have a top wall 120. In the embodiment
shown in Figure 4 the inner 150 and outer 140 walls take the form of co-axial walls
that define a cylindrical space to form the venting channel 110. The walls 150, 140
in this example take the form of concentric rings however other shapes could be used
and the term "cylindrical" is to be taken in its broadest sense in which a cylinder
of circular cross-section is only one embodiment. For example, the chimney, chimney
pot and/or liner may take a form which has a substantially rectangular cross-section
or cross-section of some other polygon (regular or irregular).
[0037] The outer or inner surface of wall 150 provides a support surface for attaching to
the top of flue liner 10 to support the liner 10 in the chimney 20. This support surface
is provided downstream of a point 155 where the wall 150 first divides a space in
a chimney or chimney pot into the central outlet 114 and ventilation channel 110 (ie
"first" in the sense of the first instance of the dividing wall 150 in the direction
of travel of the flue gases). In this way, when the flue liner 10 is connected to
the support surface, the flue liner 10 separates the outlets 114, 112, with the first
outlet 114 in gaseous communication with the flue liner 10 and the second outlet 112
in gaseous communication with the space 15 between the flue liner 10 and the chimney
20.
[0038] The top wall 120 of the chimney attachment 100 may have a step 160 as can be seen
in Figure 4. This step 160 may be provided so that, in cases when the liner 10 protrudes
above the top of the chimney pot 20, the ventilating channel 110 is maintained, and
the ingress of driving rain is reduced.
[0039] Figure 5 is a perspective view of the chimney attachment 100 illustrated in Figure
4 in isolation from the flue. The chimney attachment 100 illustrated in Figure 5,
has support tabs 130 which can be incorporated into the chimney attachment 100 for
fixing the chimney attachment 100 to the chimney pot 20. The support tabs 130 may
be an integral part of the body of the chimney attachment 100 or they may be fixed
to the chimney attachment 100. The tabs 130 may be composed of a resilient material
that can be biased to provide a gripping force on the chimney pot 20. The gripping
force may act radially inwardly on the outer surface of the pot 20 or it may act radially
outwardly on the inner surface of the pot, or tabs 130 may be provided that act in
both of these ways.
[0040] The support tabs 130 provide the double function of supporting the chimney attachment
100 on the chimney pot while providing a passage to enable ventilation. The chimney
attachment 100 can in fact be fixed to the flue in many different ways, for example
by the use of a clamp band or fixing screws. Instead of using a fixing means to fix
the chimney attachment 100 to the outside of the chimney pot 20 a fixing means could
also be used to fix the chimney attachment 100 to the flue liner 10. The fixing means
has the function of supporting the attachment on the chimney pot 20 and spacing the
outer wall 140 of the attachment 100 away from the pot 20 so as to provide the venting
channel 110. The venting channel 110 will therefore run from the inner surface of
the pot to the atmosphere on the outer side of the pot and the venting will be directed
down the outside surface of the pot.
[0041] Figure 6 is a cross-sectional view of a further embodiment of the chimney attachment
100 fitted to a flue. In this embodiment the inner 140 and outer 150 walls form a
substantially open triangular section that acts as the venting channel 120. Therefore,
the geometry of the terminal 100 is such that it does not have a top wall 120.
[0042] Figure 7 is a cross-sectional view of one side of a chimney attachment 100 according
to another embodiment of the invention. In this case the inner 150 and outer 140 walls
have an L-shaped cross-section to form the venting channel 110.
[0043] Figure 8 is a cross-sectional view of one side of a chimney attachment 100 according
to a further embodiment of the invention. In this case the inner 150 and outer 140
walls are different sections of the same curved structure.
[0044] In the embodiments of the terminal 100 illustrated in Figures 6 to 8 a fixing means
170 is shown fixing the terminal 100 to the flu liner 10, however, the fixings could
act on the chimney or chimney pot 20 instead of, or as well as, on the flu liner 10.
[0045] In the embodiment illustrated in Figures 4 to 8 the chimney attachment 100 is of
a design that can be retro-fitted to a chimney 20 and flue liner 10. In other embodiments
the chimney attachment 100 could be an integral part of a flue liner 10 or a flue
liner section 11.
[0046] Referring to Figure 9, in this embodiment the chimney attachment is a chimney pot
1100 comprising a cylindrical wall 1150. The cylindrical wall 1150 defines a first
outlet 1114 and has a hole 1112 therein that provides a second outlet. In use, a flue
liner 1010 is attached to the inside surface of wall 1150 above hole 1112 to support
the flue liner in the chimney. By connecting the flue liner 1010 in this way, the
first outlet 1114 is in gaseous communication with the flue liner 1010 and the second
outlet 112 is in gaseous communication with the space between the flue liner 1010
and chimney 1020. A guard 1070 may be provided to prevent rain water entering space
1015 through hole 1112.
[0047] A rain cap (not shown) may be added to any of the embodiments of the invention, e.g.
as shown in Figures 3 to 9. The rain cap may be configured to prevent or at least
substantially reduce the ingress of rain into the chimney without obstructing the
first outlet.
[0048] A further embodiment of the invention may be illustrated in relation to Figure 2.
The seal 40 may be replaced with a spacing member in the form of a corrugated washer.
The corrugated washer has corrugations extending in a radial direction. Accordingly,
ventilation channels are provided between the pot hanger and a topside of the washer
and between an underside of the washer and the chimney pot. The pot hanger is shaped
such that the ventilation channels are sheltered from rain.
[0049] Advantageously, as with the other embodiments of the invention, this embodiment of
the invention provides, in use, ventilation of the space between the flue liner and
the chimney, without an installer having to drill ventilation holes or install a ventilation
or air brick.
1. A chimney attachment for fitting to a chimney to support a flue liner in the chimney,
the flue liner and chimney defining a space therebetween, the chimney attachment comprising
a support for supporting the flue liner in the chimney and arranged such that connection
of the flue liner to the support provides a first outlet in gaseous communication
with the flue liner for venting flue gases to atmosphere and a second outlet in gaseous
communication with the space between the flue liner and the chimney to vent gases
in the space to atmosphere.
2. A chimney attachment according to claim 1, wherein the first and second outlets are
a common outlet, the chimney attachment comprising flue gas and ventilation flow channels,
each leading to the common outlet, the flue gas flow channel in gaseous communication
with the flue liner and the ventilation flow channel in communication with the space
between the flue liner and the chimney.
3. A chimney attachment according to claim 1, wherein the first and second outlets are
separate outlets.
4. A chimney attachment according to claim 3, comprising a wall defining a flue gas flow
path terminating in the first outlet, the wall providing a support surface to which
the flue liner can be connected, connection of the flue liner to the support surface
separating the first outlet from the second outlet.
5. A chimney attachment according to claim 4, wherein the wall defines a central void,
the void providing the flue gas flow path, and is arranged to be spaced from a chimney
or chimney pot to provide a ventilation flow path between the wall and the chimney
or chimney pot to the second outlet or wherein the second outlet is a hole in the
wall, the hole located upstream of the support surface.
6. A chimney attachment according to claim 4 or claim 5, wherein the support surface
to which the flue liner can be connected is arranged to be located downstream of where
the wall first divides a space in a chimney or chimney pot into the flue gas flow
path and the ventilation flow paths.
7. A chimney attachment according to any one of claims 1 and 3 to 6, comprising a frame
attachable to the chimney or a chimney pot, the frame comprising a support ring providing
the support for connecting to the flue liner, the support ring connectable to the
chimney such that there is a gap between a wall of the chimney/chimney pot and at
least a portion of the support ring, the gap leading to the second outlet to vent
gases in the space to atmosphere.
8. A chimney attachment according to any one of the preceding claims, wherein the second
outlet is arranged to avoid the ingress of rain water to the space between the flue
liner and the chimney through the second outlet, preferably wherein the attachment
is arranged such that, in use, the second outlet opens horizontally or/and downwardly.
9. A chimney attachment according to claim 1, claim 3 or claim 8 comprising a spacing
member and a pot hanger, wherein, in use, the spacing member is located or locatable
on top of a chimney or a chimney pot and between the chimney or the chimney pot and
the pot hanger, wherein the spacing member is shaped and dimensioned such that, in
use, the second outlet is defined at least partially by the spacing member.
10. A chimney attachment according to any one of claims 1 to 9, wherein the chimney attachment
is a chimney pot or wherein the chimney attachment is arranged to be retro-fitted
to a chimney pot.
11. A method of installing a flue liner into a chimney comprising fitting a chimney attachment
onto and/or into a chimney or a chimney pot, the chimney attachment comprising at
least one outlet, and attaching a flue liner to the chimney attachment such that the
at least one outlet is in gaseous communication with the flue liner for venting flue
gases to atmosphere and in gaseous communication with the space between the flue liner
and the chimney to vent gases in the space to atmosphere.
12. A method according to claim 11, wherein the at least one outlet comprises a first
outlet and a second outlet, the flue liner is attached to the chimney attachment such
that the first outlet is in gaseous communication with the flue liner for venting
flue gases to atmosphere and the second outlet is in gaseous communication with the
space between the flue liner and the chimney to vent gases in the space to atmosphere.
13. A method according to claim 11 or claim 12, wherein the chimney attachment is fitted
to the top of a chimney pot and preferably comprising not drilling a ventilation hole
or fitting air bricks in a chimney stack of the chimney.
14. A flue liner for a chimney comprising a chimney attachment according to any one of
claims 1 to 10.
15. In combination, a chimney having a flue liner therein and a chimney attachment, the
flue liner and chimney defining a space therebetween, the chimney attachment connected
to the flue liner to provide a first outlet in gaseous communication with the flue
liner for venting flue gases to atmosphere and a second outlet in gaseous communication
with the space between the flue liner and the chimney to vent gases in the space to
atmosphere.