Note: Descriptions are shown in the official language in which they were submitted.
CA 02526797 2011-12-07
-1-
SILL PAN FLASHING FOR DOORS AND WINDOWS
Background of the Invention
This invention relates in general to prohibiting weather-related
moisture from entering a building and, in particular, to a sill pan and
threshold
flashing unit for window and door openings in a building.
In recent years, many attempts have been made to find a solution
to the ever present problem of unwanted water and air intrusion into
buildings.
Historically, flashing is the term used to identify the means or components
utilized to prevent water intrusion. In this invention, the flashing can be
used to
control water intrusion and/or air intrusion. Controlling water and air
intrusion is a very serious concern which may result in exterior and interior
damage if not prevented or corrected in a timely manner. Recent studies have
CA 02526797 2005-11-14
-2-
shown that the extent of such damage, on an annual basis, has run into
millions
of dollars. In addition, heat loses through air leakage around window, door
and
louver openings have taken on new significance due to today's high energy
costs.
It has become imperative that a more serious approach be taken to control
water and air intrusion to reduce heating costs.
In the past, one method for dealing with the potential for water
intrusion at a door or window frame opening in an exterior building wall was
to
provide a pre-formed sill pan to collect and control the water. This objective
was accomplished with preformed plastic or metal pieces mounted along the sill
of the opening in the wall construction, to protect the underlying material
from
damage. However, such sill pans have proven to be too. expensive for all
building applications. The high cost of manufacture and wide variety of sizes
required for a vast array of door and window opening sizes has limited the
desirability of this type of device for more widespread application.
Alternatively, a surface sealed approach has been used. Putty-like
components are used to caulk around openings between the window and door
frames in an attempt to seal the gaps and prevent inward seepage of water and
air into the building. However, after a period of time, the putty-like
compounds
had a tendency to dry up, shrink and produce gaps or openings. This provides a
passageway for water and air to penetrate the building enclosure ultimately
resulting in deterioration beneath the window and door frames at the sheathing
or structural components adjacent thereto.
Tar is another option that has been used. The application of a wad
of tar at strategic locations surrounding the window or door opening may be
economical, but it is seldom effective over the long term. Moreover, it is
very
messy and difficult to efficiently apply.
CA 02526797 2011-12-07
-3-
In an effort to overcome the inadequacies inherent with caulking
and tar, advances in the chemical field have produced new sealant materials
which are better equipped to withstand the sun, temperature variations and
exposure to the elements for a longer period of time. Nevertheless, these
improved sealants eventually break down or are not initially installed
properly
resulting in water and air intrusion. Something more than caulking, tar and
sealants is desirable and new flashing materials and techniques are needed to
provide long-term and economical protection against water and air intrusion.
Known prior art attempts to provide flashing devices for the sills
of window and door openings are disclosed in U.S. Patent Nos. 993,861;
1,677,130; 4,555,882; 5,899,026; 6,401,401; and 6,401,402.
All known approaches suffer from significant problems, including
limited long-term effectiveness, inability to economically accommodate a
variety
of opening sizes, substantial expense, limited operating temperature ranges,
labor intensive construction and installation procedures, and unreliable
moisture penetration prevention.
In view of the above described conditions and consequences of
prior art solutions, a need exists for a weatherproofing solution for window
and
door opening sills or thresholds that is not subject to these shortcomings and
installation errors and lasts the life of the building structure.
Summary of the Invention
These and other problems in the prior art have been overcome by
this invention which in one embodiment includes a number of flexible
membrane flashing components utilized in combination as a uniquely formed
CA 02526797 2005-11-14
-4-
termination accessory for providing sill or threshold and end dam corner
protection at the sill or threshold areas of a roughed-in window door or other
opening. The flashing of this invention seals the sill or threshold of the
opening
with or without the use of pre-formed or molded termination accessory units in
the lower left and right corners of the opening.
As a result of unique components and their associated installation
and folding sequence, a sill or threshold flashing is created to form the
required
closure at the corner areas thus eliminating the need for a termination
accessory
unit of the type previously utilized. The uniquely folded and assembled
flashing
components of this invention are creased and folded and formable in a variety
of
sizes which can then be cut in-situ by the installer to the required
dimensions of
a particular job. It has been found that a typical window sill rough opening
can
be completely flashed by utilizing a single section of the flashing membrane
by
installing it in a particular sequence with associated components to form a
pair
of folded end dams.
In one embodiment of this invention, the flashing system for
preventing intrusion of water and air through the sill or threshold areas of
an
opening in a wall for a window, a door, and other through wall penetrations
includes a sill pan membrane having a top face and a bottom face. A first
portion of the sill pan membrane is adapted to be positioned on the sill or
threshold and an adjacent portion of a jamb of the wall opening. A second
portion of the sill pan membrane is adapted to extend rearwardly from the sill
or
threshold and jambs of the wall opening. The second portion is adapted to be
formed into a sill rear dam adjacent the sill or threshold and jambs of the
wall
opening. The sill pan membrane includes a first adhesive layer on the bottom
face of the first portion of the sill pan membrane and a second adhesive layer
on
CA 02526797 2011-12-07
-5-
the top face of the second portion. The adhesive layers each may include a
pressure sensitive self adhesive applied generally uniformly and continuously
over the respective faces of the associated portions of the sill pan membrane.
The flashing system also includes in one embodiment a pair of sill
end dams formed by folds in the sill pan membrane. Each sill end dam is
adapted to be juxtaposed to a juncture of the sill or threshold and one jamb
of
the wall opening. A pair of juncture sealing strips are each adapted to be
applied at one of the junctures of the sill and one of the jambs and over the
sill
pan membrane when installed in the wall opening. A front downwardly
depending flange formed in the sill pan membrane is adapted to be juxtaposed
to the wall opening subjacent to the sill and jambs thereof. A pair of gusset
folds
in the sill pan membrane are each adapted to be positioned proximate a
juncture between the sill and one jamb of the wall opening. Further, a pair of
termination membranes are each adapted to at least partially overlap one
another and be applied adjacent the juncture of the sill or threshold and one
of
the jambs over the sill pan membrane when installed in the wall opening. One
of the termination membranes is adapted to be applied on the sill or threshold
of the wall opening and extend forwardly and outwardly therefrom toward the
adjacent jamb and the other termination membrane is adapted to be applied on
the jamb of the wall opening and extend forwardly and downwardly therefrom.
According to one aspect of the present invention there is
provided a flashing system for preventing intrusion of water and air through a
sill area of an opening in a wall, the flashing system comprising a sill pan
membrane having a top face and a bottom face; a first portion of the sill pan
CA 02526797 2011-12-07
-5a-
membrane adapted to be positioned on the sill and an adjacent portion of a
jamb of the wall opening; a second portion of the sill pan membrane adapted
to extend rearwardly from the sill and jambs of the wall opening, the second
portion being adapted to be formed into a sill rear dam adjacent the sill and
jambs of the wall opening; a first adhesive layer on the bottom face of the
first
portion of the sill pan membrane; and a second adhesive layer on the top face
of the second portion of the sill pan membrane; wherein the adhesive layers
each further comprise a pressure sensitive self adhesive applied generally
uniformly and continuously over the respective faces of the associated
portions of the sill pan membrane.
According to a further aspect of the present invention there is
provided a flashing system for preventing intrusion of water and air through
sill area of an opening in a wall, the flashing system comprising a flexible
sill
pan membrane having a top face and a bottom face; a first portion of the sill
pan membrane adapted to be positioned on the sill and an adjacent portion of
a jamb of the wall opening; a second portion of the sill pan membrane adapted
to extend rearwardly from the sill and jambs of the wall opening, the second
portion being adapted to be formed into a sill rear dam adjacent the sill and
jambs of the wall opening; a first adhesive layer on the bottom face of the
first
portion of the sill pan membrane; a second adhesive layer on the top face of
the second portion of the sill pan membrane; wherein the adhesive layers each
further comprise a pressure sensitive self adhesive applied generally
uniformly
and continuously over the respective faces of the associated portions of the
sill
pan membrane; a pair of sill end dams formed by folds in the sill pan
membrane, each sill end dam being adapted to be juxtaposed to a juncture of
the sill and one jamb of the wall opening; a pair of juncture sealing strips
each
adapted to be applied at one of the junctures of the sill and one of the jambs
CA 02526797 2011-12-07
-5b-
and over the sill pan membrane when installed in the wall opening; a front
downwardly depending flange formed in the sill pan membrane and adapted
to be juxtaposed to the wall opening subjacent to the sill and jambs; a pair
of
gusset folds in the second portion of the sill pan membrane, each gusset fold
being adapted to be positioned proximate a juncture between the sill and one
jamb of the wall opening; and a pair of termination membranes each adapted
to at least partially overlap one another and be applied adjacent the juncture
of the sill and one of the jambs over the sill pan membrane when installed in
the wall opening, one of the termination membranes being adapted to be
applied on the sill of the wall opening and extend forwardly and outwardly
therefrom toward the adjacent jamb and the other termination membrane
adapted to be applied on the jamb of the wall opening and extend forwardly
and downwardly therefrom.
According to another aspect of the present invention there is
provided a method of flashing a sill of an opening in a wall comprising the
steps of applying a first portion of a flexible sill pan membrane on the sill
of
the opening and portions of the jambs adjacent to the sill; folding a second
portion of the flexible sill pan membrane into a sill rear dam rearwardly from
the sill and jamb portions of the wall opening; and adhesively securing the
first portion of the flexible sill pan membrane to the sill and jamb portions.
Brief Description of the Drawings
The objections and features of the invention will become more
readily apparent from the following detailed description taken in conjunction
with the accompanying drawings in which:
CA 02526797 2005-11-14
-6-
Fig. 1A is front elevational view of an exemplary rough opening in
a wall with selected sill pan flashing components according to one embodiment
of this invention installed therein;
Fig. 1B is a view similar to Fig. 1A with the flashing components
and a window installed in the opening in the wall;
Fig. 2 is a perspective view of a membrane sheet from which the
sill plan flashing component of Fig. 1A can be formed according to this
invention;
Fig. 2A is a perspective view from the rear of the membrane sheet
of Fig. 2 folded into the sill pan flashing component when installed in the
rough
opening in the wall;
Figs. 3-4 are perspective views of additional flashing components
according to one embodiment of this invention to be installed at a juncture of
the sill and a jamb of the rough opening; and
Figs. 5A-5D are sequential perspective views of components of the
sill pan flashing kit according to one embodiment of this invention being
installed in the rough opening.
Detailed Description of the Invention
Referring to Figs. 1A-1B, one embodiment of the components of a
sill pan flashing kit 1o is shown installed along the sill 12 and adjacent
lower
portions of jamb members 14 in a rough opening 16 in a wall 18 intended to
receive a window frame 20, door frame (not shown) or the like. The opening 16
also includes a header 22 spaced from the sill 12 and extending between the
spaced jamb members 14. While the flashing kit 1o is shown and described with
respect to a window frame 20 and associated opening 16, it should be readily
CA 02526797 2005-11-14
-7-
appreciated that the kit can be utilized for other wall openings, door
thresholds
and the like. As such, the term sill or variations thereof is used herein
without
limiting the invention to exclude door thresholds or any other application.
One component of an embodiment of the sill pan flashing kit io
according to this invention is a flexible sill pan membrane 24 shown
particularly
in Figs. iA and 2. In one embodiment, the flexible sill pan membrane 24 is a
polyethylene cross-laminated sheet, although other materials may be readily
utilized within the scope of this invention. The sill pan membrane 24 has a
top
face 26 and a bottom face 28. The sill pan membrane 24 is adapted to be
installed along the sill 12 of the rough opening 16 and folded along fold
lines 30
as shown in Fig. 2 to extend upwardly along the lower portion of each jamb 14
in
the rough opening 16. The sill pan membrane 24 also has a fold line 32
extending substantially the entire width of a central sill region 34 of the
membrane 24. The fold line 32 separates a sill region 34 of the membrane from
a front downwardly depending flange 36 of the membrane 24 adapted to cover
the front face 38 of the wall 18 underlying the sill 12 as shown in Figs. 1A
and 1B.
The sill pan membrane 24 is preferably cut or sliced along lines 4o and along
the
fold line 32 at the outward lateral ends thereof so that the jamb panel 42 of
the
sill pan membrane 24 can be applied to the jambs 14 of the rough opening 16
and the downwardly depending flange portion 36 can likewise be installed as
shown in Figs. 1A and 1B.
Advantageously, the sill pan membrane 24 includes two distinct
portions 44, 46. A first adhesive layer 48 is on the bottom face 28 of the
first
portion 44 of the sill pan membrane 24 as shown in Fig. 2. A second adhesive
layer 50 is positioned on the top face 26 of the second portion 46 of the sill
pan
membrane 24. The second portion 46 containing the second adhesive layer 50
CA 02526797 2005-11-14
-8-
is separated from the first portion 44 of the membrane 24 by a fold line 52
extending substantially the entire major dimension of the sill pan membrane
24.
In one embodiment, the first and second adhesive layers 48, 50 may be
rubberized asphalt adhesive or a pressure-sensitive adhesive (PSA) and covered
by a protective peel strip 48a, 5oa until the sill pan membrane 24 is to be
installed in the rough opening 16.
The sill pan membrane 24 also includes an angular fold line 54 in
each outward lateral corner area 56 of the second portion 46 as shown in Fig.
2.
The function of these angular fold lines 54 will be described later herein.
Additional components of the flashing kit 1o according to one
embodiment of this invention include a pair of juncture sealing strips 58,
each
adapted to be applied at one of the junctures of the sill 12 and one of the
jambs
14 of the rough opening 16. The juncture sealing strips 58 are intended
primarily to block exposed corners 6o formed in the sill pan membrane 24 when
it is initially installed in the rough opening 16 as shown in Fig. 1A. The
juncture
sealing strips 58 preferably include an adhesive on one surface thereof for
application of the juncture sealing strip 58 over top of the top face 26 of
the sill
pan membrane 24. The juncture sealing strips 58 cover the juncture between
the associated jamb 14 and sill 12 of the rough opening 16 on top of the sill
pan
membrane 24 and extend downwardly and outwardly therefrom to the front
face 38 of the wall 18 adjacent the rough opening 16.
The flashing kit 1o according to one embodiment of this invention
also includes a pair of termination membranes 62, 64 (Figs. 3 and 4) which are
particularly adapted for installation at the left end of the sill 12 as shown
in Figs.
1A and 1B. One of ordinary skill in the art will appreciate that complementary
termination membranes, which are mirror images of those shown in Figs. 3 and
CA 02526797 2005-11-14
-9-
4, are utilized at the right side end of the sill 12 according to this
invention. The
termination membranes 62, 64 are each adapted to at least partially overlap
one
another and be applied adjacent the juncture of the sill 12 and one of the
jambs
14 over the sill pan membrane 24 and juncture sealing strips 58 when installed
in the wall opening. The termination membrane 64 shown in Fig. 4 includes a
generally rectangular portion 66 separated by a fold line 68 from a downwardly
depending flange 7o having an angular edge 72. The rectangular portion 66 of
the termination membrane 64 of Fig. 4 is intended to overlap the sill pan
membrane 24 on the sill 12 of the rough opening 16 with edge 74 of the
membrane 64 juxtaposed to the jamb 14. The downwardly depending flange 70
is intended to overlap a portion of the flange 36 of the sill pan membrane 24
and
be folded downwardly along the fold line 68. The angular outwardly projecting
edge 72 extends outwardly from the rough opening 16 as shown in Fig. 5B.
The other termination membrane 62 of Fig. 3 includes a pair of
rectangular portions 76, 78 separated by a fold line 80. The termination
membrane 62 is intended to be applied along the jamb 14 of the rough opening
16 adjacent to the sill 12. The downwardly projecting portion 78 of the
termination membrane 62 extends below the sill 12 of the rough opening 16 and
overlaps the angular projection 72 of the termination membrane 64. The
termination membranes 62, 64 each include an adhesive layer 62a, 64a on a
bottom face thereof for convenient and easy application and installation.
The installation of the components of the flashing kit 1o according
to this invention is shown sequentially in Figs. 5A-5D. Prior to installing
the
flashing kit 10, any housewrap should be removed from the sill 12 and adjacent
portions of the jambs 14. The surfaces of the sill 12 and jambs 14 should be
CA 02526797 2005-11-14
-10-
smooth, dry and free from dirt, debris, ice and other foreign material. These
surfaces of the sill 12 and jambs 14 should be primed.
The sill 12 of the rough opening 16 is covered by the sill region 34
and sill pan membrane 24 as shown in Figs. 1A and 5A with the second portion
46 extending rearwardly from the rough opening 16 and the downwardly
depending flange 36 positioned along the face 38 of the wall 18 subjacent to
the
rough opening 16 as shown in Figs. 1A and 5A. Advantageously, the first
adhesive layer 48 on the bottom face 28 of the first portion 44 of the sill
pan
membrane 24 securely mounts the sill pan membrane 24 to the sill 12 and lower
jamb portions 14 once the peel strip 48a is removed. Then the membrane 24 is
folded along the fold lines 3o and slit or cut along cut lines 40. The sill
pan
membrane 24 may be conveniently cut from a roll of membrane material to a
length appropriate for the size of the sill 12 and rough opening 16 to be
flashed.
The first portion 44 should extend about three inches up each jamb 14 from the
sill 12. One technique for installing the first portion 44 of the sill pan
membrane
24 is to begin application on one of the jambs 14 and proceed downwardly
toward the sill 12, across the sill 12 and then up the other jamb 14, removing
the
peel strip 48a as needed.
Next, the juncture sealing strips 58 are installed at the juncture
between each jamb 14 and the sill 12 as shown in Figs. 1A and 5A to cover the
exposed corners 6o. Additional flashing protection is provided by the
installation of the termination membranes 62, 64. The termination membrane
64 is installed as shown in Fig. 5B adhesively secured in place on top of
portions
of the sill pan membrane 24 and juncture sealing strip 58.
Next, the termination membrane 62 is installed along the lower
portion of the jamb 14 adjacent the sill 12 to cover the exposed portion of
the
CA 02526797 2005-11-14
-11-
juncture sealing strip 58 and the jamb portions 42 of the sealing membrane 24.
Likewise, the angular projecting portion 72 of the termination membrane 64 is
also covered by the downwardly projecting portion 78 of the termination
membrane 62. Once the sill membrane 24, juncture strips 58 and termination
membranes 62, 64 are installed as shown and described in Figs. 5A-5C for both
jamb portions 14 of the rough opening 16, the window frame 20, door frame or
the like is installed in the rough opening 16 as shown in Fig. 1B.
A sill rear dam 82 is then formed in the second portion 46 of the
sill pan membrane 24 as shown in Figs. 5D. After the peel strip 5oa is
removed,
the second adhesive layer 5o is exposed on the second portion 46 of the sill
pan
membrane 24. The second portion 46 is then folded upwardly along the fold
line 52 as shown by arrow A in Fig. 5D. Advantageously, the second adhesive
layer 50 is on the top face 26 of the sill pan membrane 24. When the second
portion 46 is folded upwardly, it is likewise folded along each of the angular
fold
lines 54 to form a gusset 84 extending outwardly from the rough opening 16 as
shown by arrow B in Fig. 5D and attached to the frame 20. The confronting
surfaces of the corner area 56 on the second portion 46 of the sill pan
membrane
24 contain portions of the second adhesive layer 5o and are therefore readily
sealed with each other to form the gusset and maintain the second portion 46
of
the sill pan membrane 24 into the sill rear dam 82 adjacent the jambs 14 of
the
wall opening 16. The configuration of the sill pan membrane 24 when cut and
folded is shown from a rear perspective view in Fig. 2A. Once folded into this
configuration, fasteners such as staples, tacks, nails or the like 86 may be
inserted through the rear of the sill rear dam 82 and into the wall 18 and/or
window frame 20 installed in the rough opening 16.
CA 02526797 2005-11-14
-12-
After the components of the flashing kit to are assembled and
installed as described and shown herein, the window frame 20, door frame or
the like may be inserted into the rough opening 16 as shown in Fig. 1B with
the
sill area thereof being sealed against air and water intrusion through the
wall 18.
Advantageously, the materials of the flashing kit 1o according to one
embodiment of this invention do not tear or deform when the frame 20 is being
installed in the rough opening 16 nor do they mar or fowl the frame 20 as with
prior art materials such as tar and the like. The sill rear dam 82 can be
formed
with the gussets 84 after the frame 20 is installed and then tacked to the
frame
20 as shown in Fig. 2A.
Advantageously, the membrane 24 can be cut and sized to flash
the sill 12 of an opening 16 of any size in the wall 18 on-site thereby
providing an
efficient and economical solution to inhibit water and moisture from entering
the building structure through the opening 16.
The various components of the flashing kit 1o according to this
invention may be made of any of a variety of known materials suitable for
flashing a rough opening 16 in a wall 18. Presently preferred materials for
the
membrane are uncured rubber, cured rubber and cross-laminated polyethylene.
Another material for the flashing member 24 according to this invention is
FlexwrapTM commercially available from Tyvek . Generally, the FlexwrapTM
product is a butyl compound containing melamine, cyanurate and aluminum
hydroxide as fire retardants. The adhesive 32 may be a pressure sensitive
adhesive (PSA) or butyl adhesive containing a non-halogen fire retardant
additive and is covered with a release liner or peel strip as is well known.
Other
materials which may be suitable for one or more of the components of the
CA 02526797 2005-11-14
-13-
flashing kit 10 of this invention may be sheet metal, with or without adhesive
for
mounting to the opening 16 in the wall 18.
Preferably, the membrane 24 is available in roll form and can be
cut to the approximate dimensions. The membrane 24 is provided with the peel
strips 48a, 5oa and a pressure sensitive adhesive 48, 50 on opposite sides.
Finger pressure is applied to insure good contact and removal of any air
bubbles
which may reside thereunder. Again, as with the silicone rubber adhesive
sealant, this product readily bonds and adheres to the itself and the surface
on
which it is applied.
As can be seen from the foregoing drawings and their descriptions,
there has been set forth several embodiments and options available to a
builder
to prevent water and air intrusion around windows and door openings. This
system provides an economical, less time consuming, effective procedure for
solving a very serious problem in the construction industry.
From the above disclosure of the general principles of this
invention and the preceding detailed description of at least one preferred
embodiment, those skilled in the art will readily comprehend the various
modifications to which this invention is susceptible. Therefore, I desire to
be
limited only by the scope of the following claims and equivalents thereof.
1 claim:
