Note: Descriptions are shown in the official language in which they were submitted.
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FLASHING FOR INCLINED ROOF AND METHOD FOR
INSTALLING THE SAME
FIELD OF THE INVENTION
The present invention relates to a flashing useful for weatherproofing an
aperture made in an inclined roof.
The invention also relates to a method for installing such a flashing onto a
roof.
BACKGROUND OF THE INVENTION
It is of common practice in the construction industry to use a flashing to
seal the
interstitial gap between the roof and a vertical member such as a pipe, a
venting
is : duct or a chimney passing through an aperture made in this roof.
In addition to ensuring weatherproofing of the roof aperture, the flashing is
usually also devised to ensure proper drainage of the water that can
accumulate on the roof.
Currently, a variety of roof flashings of different shape are available for
weatherproofing an aperture made in a roof to allow passage of a vertical
structure. Figures 1A to C show three examples of such flashings respectively
called "flat flashing", "gable flashing" and "pitched flashing".
The flat flashing shown in Figure 1A is commonly used for waterproofing an
opening in a flat roof or building surface.
The gable flashing shown in Figure 1 B is used for weatherproofing an opening
in the peak of an inclined roof.
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Last of all, the pitched flashing shown in Figure 1 C is used for
weatherproofing
an opening on a an inclined roof, such as a pitched, lean-to, pavilion or
gable
roof. In the latter case, the surrounding member of the gable flashing which
is
usually of the conical shape must extend from the flat base of the flashing in
s such an inclined direction as to accommodate the roof slope.
In use, the flat base of the pitched flashing is positioned over the aperture
made
in the inclined roof and fastened on the same.
io As is known, the roofs can be made of variety of materials, like for
example
tiles, stainless steel or other metal alloys, PVC or other polymeric
materials,
bitumen or fiberglass. Some of these roof materials can also be in the form of
corrugated sheets. In the latter case, condensation and moisture can
accumulate in their grooves. When used to insulate a roof covered with a
rs corrugated material, pitched flashings of conventional structure, viz. with
a flat
base, may obstruct these grooves and thus not allow efficient drainage of
water
that may accumulate. Furthermore, the installation of such flashings can be
problematic depending on the shape of the ridges on the roof material.
20 SUMMARY OF THE INVENTION
A first object of the present invention is to provide a roof flashing for use
on an
inclined roof, which is different from the known pitched flashings and
overcome
some of their disadvantages, in particular when used on inclined roofs of
25 corrugated surfaces.
More specifically, the first object of the present invention is to provide a
flashing
for weatherproofing an aperture made in an inclined roof, to allow the passage
of substantially vertical member through this inclined roof.
Like the existing pitched flashings, the flashing according to the invention
comprises a base member adapted to be mounted over the aperture made in
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the inclined roof, and a surrounding member extending upwardly from the base
member to fit around the vertical member passing through the roof.
The base member comprises a covering panel of quadrilateral shape. This
covering panel has a top edge which is adapted to be positioned on an upper
part of the inclined roof and a bottom edge which is adapted to be positioned
on a lower part of this roof. The covering panel also comprises two opposite
side edges and an opening, this opening being large enough to allow the
passage of a vertical structure passing through the roof.
In accordance with a very specific feature of the invention, the base member
also comprises a bottom sidewall projecting downwardly from the bottom edge
of the covering panel, and two lateral sidewalls that respectively extend
downwardly from the opposite side edges of the covering panel and sidewardly
from the back wall in a tapering fashion. As may be appreciated, the covering
panel, bottom sidewall and lateral sidewalls of the base member altogether
define a hollow housing.
2o The tubular surrounding member is attached to, and extends upwardly from
the
base member. This surrounding member comprises a top opening which is
sized to tightly fit around a vertical structure passing through the inclined
roof.
It also comprises a bottom opening coaxially positioned on top the opening of
the covering panel of the base member, and sized to allow passage
therethrough of a vertical structure.
In accordance with a particularly preferred embodiment of the invention, the
surrounding member of the flashing is funnel-shaped and has its top opening
smaller in size than its bottom opening. Preferably, this surrounding member
3o has a central axis inclined toward the top edge of the covering panel of
the base
member. Preferably also, the top opening of the surrounding member is
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substantially circular in shape and its botfom opening is substantially
elliptic in
shape.
In another particularly preferred embodiment of the invention, the lateral
sidewalls of the base member are shorter in length than the covering panel of
the base member. Preferably also, the flashing according to the invention is
made of welded metal.
In accordance with a further preferred embodiment of the invention, the base
io member also comprises flanges projecting outwardly from each lateral
sidewall
to facilitate fastening of the flashing to the roof.
Another object of the invention is to provide a method for installing the
flashing
according to the invention as disclosed hereinabove. This method comprises
four basic steps.
The first step consists in cutting a slot in the upper part of the inclined
roof
above the aperture made therein. This slot needs to be large enough to receive
the top edge of the covering panel of the base member.
The second step consists in inserting the top edge of the covering panel into
the slot.
The third step consists in positioning the bottom sidewall of the base member
onto the lower part of the inclined roof in such a manner that the bottom
opening of the surrounding member is located on top of the roof aperture.
The fourth step consists in fastening the base member to the inclined roof
with
suitable fastening means such as screws and nails.
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In use, the aperture made in the roof can be of a shape different from the one
of opening made in the flashing. The roof aperture can, for example, be
rectangular.
5 The method according to the invention may also comprise additional optional
steps. By way of example, it may comprise the additional step of applying a
sealant to the junction of the roofing material and the base member of the
flashing.
lo The method may also comprise the additional step of installing a storm
collar
around the top opening of the surrounding member and the vertical structure
for
further sealing any space left in-between them.
The method according to the invention may further comprise the additional step
of inserting the top edge of the covering panel of the base member into the
roof
slot to such a depth that the top edges of the lateral sidewalls of the base
member rest adjacent to this roof slot.
In accordance with a particularly preferred embodiment of the method, the
fastening means are used to fasten to the roof the flanges projecting
outwardly
from each lateral sidewall of the base member.
Thanks to its particular structure and the way it is installed, the flashing
according to the invention may be installed in a very easy and efficient
manner
on any kind of roofs, including roofs with a corrugated structure defining
downwardly oriented ridges.
In such a case, one has only to cut for indentations to be into the bottom
sidewall of the base member. These indentations must be large enough to
~o receive the ridges of the corrugated roof. However, they can easily be
"adjusted" to fit any kind of corrugated roofing material whatever be the form
of
their ridges (square, round, sinusoidal, etc.).
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The same flashing can also be installed in an easy and efficient way on an
inclined metal roof.
In all cases, the problem of water drainage mentioned hereinabove is solved.
Thus, the flashing according to the invention is very efficient and versatile
and
can be used in an efficient way on any kind of roof.
The invention and its advantages will be better understood upon reading the
lo following non-restrictive description of a preferred embodiment of it, made
with
reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figures 1A to 1 C identified as "prior art" are perspective views of three
different
kinds of flashing already in use;
Figures 2A and 2B are side elevational views of two flashing according to the
invention, which are respectively adapted for use with roofs of different
angulation;
Figure 3 is a top plan view of the flashing according to the invention as
shown
in Figure 2A;
Figure 4 is a top plan view of the sheet of metal used to make the base
member of the flashing shown in Figures 2A and 3, before this sheet is
processed and folded to form a hollow housing;
Figures 5A to 5C are perspective views showing successive steps of the
installation of a flashing according to the invention onto a corrugated roof.
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Figure 6 is a perspective view of the flashing shown in Figures 2B, 3 and 4
after
it has been installed onto a roof and the installation of the chimney has been
completed.
Figure 7 is a is a top plan view of a flashing according to the invention with
flanges projecting outwardly from each lateral sidewall.
Figure 8 is a is a top plan view of the sheet of metal used to make the base
member of the flashing shown in Figure 7, before this sheet is processed and
folded to form a hollow housing.
io Figure 9A to 9C are perspective views showing successive steps of the
installation of the flashing shown in Figure 7 onto a corrugated roof.
DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION
As aforesaid, the flashing 1 according to the invention is intended to be used
for
weatherproofing the gaps that exist in-between an inclined roof 3 and a
vertical
member passing therethrough, such as a chimney 5 as shown in the illustrated
embodiment (see Figure 6) or alternatively a pipe, a venting duct or any other
kind of member having to pass through the roof.
The flashing 1 comprises a base member 7 adapted to be mounted over the
aperture 9 made in the inclined roof 3 to allow passage of the chimney 5 (see
Figure 5B). The flashing 1 also comprises a surrounding member 11 extending
upwardly from the base member 7 to fit around the chimney 5.
As better shown in Figures 2A, 2B, 3 and 4, the base member 7 is in the form
of a hollow housing.
It comprises a covering panel 13 of quadrilateral shape having a top edge 15
3o adapted to be positioned on an upper part of the inclined roof, a bottom
edge
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17 adapted to be positioned on a lower part of the inclined roof and two
opposite side edges 19, 21. The covering panel 13 is provided with an opening
28 large enough to allow passage of the chimney 5 therethrough.
The base member also comprises a bottom sidewall 23 projecting downwardly
from the bottom edge 17 of the covering panel and two lateral sidewalls 25, 27
that respectively extend downwardly from the opposite side edges 19, 21 of the
covering panel and sidewardly from the bottom sidewall 23 in a tapering
fashion. As aforesaid, the covering panel 13, the bottom sidewall 23 and
lateral
io sidewalls 25, 27 altogether define a hollow housing.
As is shown in Figure 4, the base member 7 can be made from a metal sheet
cut in such a way that, after properly folding its lateral and bottom parts,
the
requested bottom and lateral sidewalls 23, 25 and 27 of the base member 7 are
"created" and properly positioned to allow welding of their adjacent edges to
achieve the requested hollow housing form.
Preferably, as shown in Figures 2A and 2B, the lateral sidewalls 25, 27 of the
base member 7 are shorter in length than the covering panel 13. Such allows
formation of a flat flange adjacent to the top edge 15 and thus facilitates
insertion and positioning of the top edge of the base member 7 in the slot cut
in
the roof during installation of the flashing, as will be better explained
hereinafter.
Also preferably, as shown in Figure 7, the base member 7 comprises flanges 38
flanking both lateral sidewalls 25, 27 to help in securing the base member 7
to
the roof.
As also shown in the drawings, the surrounding member 11 is tubular in shape,
preferably made of metal too, and attached to the base member 7 by welding.
3o The surrounding member 11 comprises a top opening 29 sized to tightly fit
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around the chimney 5; and a bottom opening coaxially positioned on top the
opening 23 of the covering panel 13 of the base member. Of course, the bottom
opening must also be sized to allow passage therethrough of the chimney 5.
As shown, the surrounding member 11 is preferably shaped as a funnel. Thus,
its top opening 29 is smaller in size than its bottom opening.
Inasmuch as, in most constructions, the chimney 5, pipe or other member that
have to pass through the roof, extend vertically and the roof on which the
1o flashing 1 is intended to be installed for weatherproofing purpose is
itself
inclined, the surrounding member 11 has to be oriented at an angle selected as
a function of the inclination of the roof. In other words, the central axis
"X" of
this surrounding member 11 will be inclined toward the top edge 15 of the
covering panel 13 of the base member 7.
In such a case also, the top opening 29 of the surrounding member 11 will be
substantially circular in shape and the bottom opening of the surrounding
member will substantially elliptic in shape and sized to match the size of the
opening 23 made in the covering panel 13 of the base member 7.
Figures 2A and 2B are illustrative of the shape and inclination that may have
the
surrounding member 11 as a function of the actual slope or inclination of the
roof. Figure 2A shows the shape that the flashing 1 must have to fit on a roof
having a pitch of 1/12 to 7/12. Figure 2B shows the same shape for a flashing
adapted to fit on a roof with a pitch of 8/12 to 12/12 (2B). The expression
"roof
pitch" as used hereinabove refers here to a measurement used to quantify the
steepness a roof. It is measured by the rise in inches for each 12 inches of
horizontal run. The larger the fraction, the steeper the roof is. Of course,
other
shapes could be selected depending on the user's needs.
The following Tables 1 and 2 summarize the dimensions that may have the
flashing 1 according to the invention as shown in the accompanying drawings.
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As can be appreciated, these dimensions vary as a function of the diameter of
the chimney. Value (A) is a measurement of the length of both the top and
bottom edges 15, 17 of the base member 7. Value (B) represents the length of
the covering wall 13 of the base member. Value (C) denotes the width of the
5 bottom opening of the surrounding member 11 and value (D) the diameter of
the top opening 29 of the same member 11. Value (E) represents the length of
the bottom opening of the surrounding member 11.
TABLE I
Dimensions (in inches) of a flashing for a roof with a pitch of 1/12 to 7/12
(see
figure 2A)
Diameter of 5 6 7 8
the chimney
(inches)
A 24 24 24 24
B 24 24 24 26
C 12 1/8 13 1/8 13 1/2 14 1/2
D 7 3/8 8 3/8 9 3/8 10 3/8
E 12 5/8 13 7/8 14 1/4 15 3/8
TABLE 2
Dimensions (in inches) of a flashing for a roof with a pitch of 8/12 to 12/12
(see
figure 2B)
Diameter of 5 8 7 8
the chimney
(inches)
A 24 .24 26 26
B 28 26 28 30
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C 14 3/8 13 3/a 15 1/8 16%
D 7 3/8 8 3/8 9 3/8 10 3/8
E 17 1/8 16 1/2 18% 19 7/8
TABLE 3
Dimensions (in inches) of a second embodiment of a flashing for a roof with a
pitch of 1/12 to 7/12
Diameter of 5 6 7 8
the chimney
(inches)
A 243/4 24% 243/ 24%
B 21% 21% 213 233/
C 29 1/8 29 1/8 29 1/8 29 1/8
D 24 24 24 26
E 7 3/8 8 3/8 9 3/8 10 3/8
TABLE 4
Dimensions (in inches) of a second embodiment of a flashing for a roof with a
pitch of 8/12 to 12/12
Diameter of 5 8 7 8
the chimney
(inches)
A 243/ 243/ 263/ 26%
B 25% 23% 25% 27%
C 25 5/8 29 1/8 31 5/8 32 1/16
D 28 26 28 30
E 7 3/8 8 3/8 9 3/8 10 3/8
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TABLE 5
Dimensions (in inches) of a flashing for a roof with a pitch of 12/12 to 21/12
Diameter of 5 8 7 8
the chimney
(inches)
A 263/a 26% 263 26%
B 31% 37% 38% 403/a
C 31 3/16 31 3/16 31 3/16 31 3/16
D 3134 37% 38% 40%
E 7 3/8 8 3/8 9 3/8 10 3/8
As disclosed hereinabove in the Summary of the Invention, the flashing I
according to the invention can be installed in a very simple yet efficient way
with
io a method involving four basic steps to which may be added a plurality of
optional steps.
As shown in Figures 5A to 5C, the installation of the flashing 1 onto a roof
through which passes a chimney 5 as illustrated in Figure 6, may be carried
out
using the following sequence of steps:
1. aligning the axis "X" (or centerline) of the flashing 1 with the centerline
"Y"
of the chimney, as shown in Figure 5A.
2. drawing the interior outiine of the surrounding member 11 of the flashing
on
the roof, as shown in Figure 5B.
3. removing the flashing 1 and cutting an aperture 9 in the roofing material
by
following the previously drawn interior outline.
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4. cutting a slot 31 parallel to the peak of the roof and centered along an
axis
passing through the middle of the aperture 9, so as to receive the top edge
15 of the covering panel 13 of the basic member 7;
5. inserting the top edge 15 of the base member 7 of the flashing into the
slot
31 and resting the bottom sidewall 23 of the base member 7 of the flashing
towards the bottom part of the roof, such an insertion into the slot 31 being
preferably made to such a depth that the top edges of said lateral sidewalls
27 of the base member rest adjacent to the roof slot 31 ;
6. outlining the profile of the roof ridges 33 in the case the roofing
material is
corrugated as shown in the drawings and has such ridges, on the bottom
sidewall of the flashing and cutting indentations 35 that correspond to the
shape of the roof ridges and are large enough to fit these roof ridges, as
shown in Figure 6;
7. fastening the flashing to the roof using, for example, at least six wood
screws sealed with metal/rubber washers or silicone or alternatively nails or
other fixation means;
8. sealing the base member 7 of the flashing 1 at the roof junction with an
external grade sealant;
9. inserting the chimney 5 through the flashing; and
10. installing a storm collar 37 around the junction of the flashing 1 and the
chimney 5 and optionally sealing the storm collar 37 to the chimney 5 with
a caulking roll (ECR'm) or silicone.
In a preferred embodiment of step 7, as illustrated in Figure 9C, the
fastening
of the flashing to the roof may be carried out by fixing the flanges 38 to the
roof
with the aforesaid fixation means.
As aforesaid, a main advantage of the flashing according to the invention is
that
it can be efficiently installed onto a corrugated roof. In such a case and as
already disclosed hereinabove (see step 6), indentations 35 can be cut into
the
bottom sidewall 15 of the flashing 1 so as to fit the ridges of the roofing
material.
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Such makes it possible to install the flashing 1 onto any kind of inclined
corrugated roof, especially made of metal while providing an efficient
insulation
from the outside and more particularly from moisture.
Another advantage of the invention is that the flashing 1 provides an easy and
simple way to seal any gaps formed in-between an inclined roof and a vertical
structure passing through this roof. This flashing is particularly useful when
used on inclined corrugated metal roofs.
lo Of course, it may be understood that the present invention has been
described
in detail hereinafter and illustrated in the accompanying drawings. As a
matter
of fact, numerous obvious modifications could be made to it without departing
from the scope or spirit of the present invention.
