Note: Descriptions are shown in the official language in which they were submitted.
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WINDOW WRAP
1. Field of the Invention
The invention relates generally to window wraps, and, more particularly, to a
window wrap that may be used to finish the drywall edges around windows.
2. Background of the Invention
A window frame typically consists of side jambs and a head and bottom sill,
formed in a rectangular shape. When a building is being constructed, a rough
window frame is constructed, providing a space for a window through the wall.
The
rough frame may be constructed of a variety of materials, depending on the
construction of the wall in which the window will sit, however typically the
rough
frame is constructed with 2x4 or 2x6 studs. Drywall may then be placed over
the
framing surface of the wall, and around the rough window frame opening. The
drywall around the rough window frame is then either finished by forming
corners
with drywall panels used to form the jambs and sills of the finished frame,
using any
of the conventional means for finishing drywall corners, or a window wrap is
constructed out of wood or other materials, to provide the finished frame and
cover
the unfinished edges of the drywall around the window frame.
These conventional methods of constructing a finished window frame is time
consuming, and to be done properly, requires the skills of an experienced
craftsman.
Drywall panels are widely used in the construction industry for forming the
interior walls and ceilings of rooms. Drywall panels are made of a gypsum or
reinforced gypsum core covered with paper. Drywall panels have the advantages
of
being easy to cut to desired sizes and to attach to assorted types of framing.
However, it is very difficult to cut drywall panels so that the edges are
perfectly
straight and smooth and can meet to form a perfectly straight corner, which is
aesthetically to be desired. In addition, when the drywall panels are cut to
the
desired sizes, the edges of the panels are left exposed. This exposed gypsum
core
is soft and tends to crumble unless the severed edges are somehow protected.
This
is especially important at outside wall corners.
When window frames are built of framing materials such as wood, the inside
and outside corners thereby formed are seldom perfectly straight. Small
variations in
the sizes of the wood-framing members, warping of the wood, and inconsistent
building practices lead to imperfectly straight corners where walls and window
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frames meet. When drywall panels are then attached to the crooked framing
materials, their intersections will also be crooked.
An assortment of devices have been used to provide a smooth and durable
finish for the intersections where two pieces of drywall abut to form an
inside or
outside corner, such as are present in finished window frames, Among the
conventional devices used are drywall tape and metal corner beads.
Conventional
drywall tape is provided in narrow, elongated ribbons or strips of porous
paper
wound into rolls. The paper is sometimes perforated to increase moisture
penetration and to prevent air bubbles from being entrapped behind the tape.
The
drywall tape is first applied to joints and edges of abutting drywall panels
and is then
covered with wet plaster, sometimes called "mud". The plaster is feathered and
smoothed along the edges of the tape to conceal the demarcations between the
tape
edges and the drywall panels to which the tape is applied. When the wet
plaster has
dried, the tape and drywall can be painted or otherwise covered with a
suitable wall
covering.
A great deal of skill is needed to apply the plaster to both sides of an
inside
corner such that a perfectly straight intersection is achieved. Also, to
correct the
crookedness resulting from the warped framing members and inconsistent
building
practices described above often several coats of plaster must be applied, with
an
entire day of drying time needed between each coat. Even then, a perfectly
straight
corner seldom results. It is also likely that, unless in the most highly
skilled hands,
the plaster trowel will mar the first side of the plaster while the second
side is being
applied. Once the plaster has been applied and dried, it must be sanded to an
appropriate finish to provide a surface suitable for the application of paint
or
wallpaper.
Because drywall tape is formed of paper, it is quite flexible and will conform
to
various surface configurations of the edges of infiersecting panels of
drywall. When
conventional drywall tape is used at the outside corners of walls, the
flexibility of the
tape often results in a corner demarcation that is irregular, since the tape
conforms
to irregularities in the exposed, severed edges of the drywall panels. The
tape is
also fragile and does not stand up well to the constant physical abuse
suffered by
outside corners. As a consequence, conventional drywall tape cannot be used at
exposed outside corners.
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To finish outside corners in building construction, therefore, metal corner
beads are often used. Conventional metal beads are configured in an L-shaped
or
angle-shaped cross section and are typically fabricated from elongated
perforated
strips of metal, such as galvanized steel, permanently deformed with a
lengthwise
90-degree bend to form elongated angles. The metal beading is typically
positioned
at the intersections of adjacent drywall panels that meet at right angles to
form an
outside corner within a roam. The sections of metal beading are nailed in
place
through the drywall panels to wooden supporting structural members located
behind
the drywall panels. Wet plaster is then smoothed into place to cover the metal
flanges or leg members of the metal beading, and the edges of the plaster are
smoothed and feathered to attempt to conceal the metal edges.
While the rigidity of the metal beading does allow an outside corner of an
inside building wall to be finished with a sharp, straight edge, which is
aesthetically
pleasing, the use of metal beading involves some significant problems. Over
time,
the metal corner bead will rust, thereby producing rust stains that are
clearly visible
on the surfaces of the walls at the corner. (t is not always possible to
completely
cover the edges of the metal flanges or the nail heads used to attach the
metal
corner bead to the drywall panel, detracting from the desired smooth
appearance of
the wall. Cracks often develop in the overlying plaster at the outer edges of
the
flanges. To prevent this from happening, often two or three coats of plaster
are
applied, with prior coats allowed to dry and harden, which may take as long as
24
hours, before a subsequent coat is applied. When the corners are crooked or
jagged
due to problems with the underlying framing, metal beads do not cover enough
surface area or have enough flexibility to correct the inequalities that
exist. Another
problem is inherent in the tact that the malleable metal from which tfi'e
metal beads
are made has a very poor memory and is subject to being dented or wrinkled,
after
which it is difficult to straighten it to produce a smooth finish. Because of
the rough
handling to which most of the material at a work site is subjected, it is not
uncommon
for the strips to be wrinkled, dented, and perhaps twisted, thus rendering
them either
unusable, or usable only to produce an inferior end result. In addition, the
metal
strips are used in large quantities in construction and can add up to
considerable
cost.
Furthermore, when drywall corners are used to finish the window frame, the
resulting frame is not very insulated. This type of frame is also not very
strong and
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cracks often times develop at the corners of the window frame. Outside air
leakage
will then also occur.
If a conventional window wrap is used, the resulting frame is stronger and
may be more insulated, however, its use requires extra time, material and
expense
to install. Such conventional window wraps are also prone to outside air
leakage.
Therefore, a need exists for a window wrap that protects the edges of the
drywall used around the window, provides pertectly straight corners for the
finished
window frame, is strong, insulated, eliminates outside air leakage around the
window
frame, and is easy and economical to use.
None of the described conventional ways of finishing a window frame fulfills
these needs.
The window wrap described herein is able to fulfill all these before described
needs. The window wrap has perfiectly formed corners and may be used for any
depth jamb/sill. The window wrap covers and protects the exposed edges of
drywall
around the inside edge of the window frame, and is adjustable to fit various
thicknesses of drywall panels. The window wrap may be insulated and may be
sealed to prevent outside air leaks. Finally, the window wrap may be
economically
manufactured due to its simplified cross-sectional shape.
SUMMARY OF THE INVENTION
A window wrap used to accommodate and protect various thicknesses of
drywall around a rough window frame, which forms a window frame with perFectly
square corners. The window wrap has a jamb/sill extension and a wall
extension,
each extending perpendicular to each other. The wall extension has a front
surface,
a rear surface, and a distal surface extending between the front and rear
surfaces,
and is adjustable to tit various thicknesses of drywall panel. A layer of
primer or
adhesive laminate is applied to the front surface of each extension so that
paint can
bond to the front surface. The jamb/sill extension of the window wrap may also
be
made similar to the wall extension and used to form any depth of jamb/sill.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention can be more readily understood in conjunction with the
accompanying drawings, in which:
Fig, 1 is a partial perspective view of one embodiment of the component used
to form each portion of the window wrap in accordance with the present
invention;
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FIG. 1a is a partial perspective view an alternative embodiment of the
component used to form each portion of the window wrap in accordance with the
present invention;
FIG. 1 b is a partial perspective view an another alternative embodiment of
the
component used to form each portion of the window wrap in accordance with the
present invention;
FIG. 2 shows a cross-sectional view of the preferred component used to form
each portion of the window wrap in accordance with the present invention;
FIG. 3 is a detailed cross-sectional view taken from the outlined section of
FIG. 2 showing the front surface of the drywall corner finishing device used
to form
each portion of the window wrap in accordance with the present invention
covered
with a layer of primer;
FIG. 4 shows a detailed cross-sectional view taken from the outlined section
of FIG. 2 showing the front surface of the drywall corner finishing device
used to form
each portion of the window wrap in accordance with the present invention
covered
with a layer of adhesive laminate;
FIG. 5 shows a cross-sectional view of the drywall corner finishing device
used to form each portion of the window wrap in accordance with the present
invention bent 90° to form an outside corner.
FIG. 6 is a detailed cross-sectional view of the center joint of the drywall
corner finishing device as shown in FIG. 2, showing an embodiment of the
device
with a tapered joint;
FIG. 7 is a partial perspective view of two drywall corner finishing devices
each bent to form outside corners, with their ends cut at an angle to form a
90°mitered joint when placed together.
FiG. 8 shows a front perspective view of four drywall corner finishing
devices,
each bent to form outside corners, and their ends cut at an angle to form a
90°miter-
joint with each other, and joined together to form the window wrap of the
present
invention.
FIG. 9 shows a rear perspective view of the window wrap shown in F1G 8.
FIG. 9a shows a rear perspective view of an alternative embodiment of the
window wrap.
F1G. 10 is a front view of the window wrap of the present invention.
FIG. 11 is a rear view of the window wrap of the present invention.
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FIG. 12 is a side view of the window wrap of the present invention.
FIG. 13 is a cross-sections! view~~of the wall or jamb/sill extension showing
its
use with a drywall panel with the application of plaster between the drywall
panel and
the extension.
FIG. 14(a), 14(b) and 14(c) are partial cross sections of the wall or
jamb/sill
extension illustrating the use of the extension with a'/2" thick drywall
panel. '
FIG. 15(a) and 15(b) are partial cross sections of the wall or jamb/sill
extension illustrating the use of the device with a 518" thick drywall panel.
F1G. 16 is a further partial cross-section of the wall or jamb/sill extension
illustrating the use of the device with a 5/8" thick drywall panel and a block
as affixed
to a framing structure.
DETAILED DESCRIPTION
Drywall panels are conventionally supplied in predetermined widths, for
example 3/8 inch, %2 inch, and 5l8 inch widths, etc., and not meant to be
inclusive.
The window wrap of the present invention is able to conform to any width of
drywall
panel used.
The window wrap of the present invention is preferably fabricated using
drywall corner finishing device components which are the subject of a previous
but
co-pending patent application, Application number 09!888,011. Therefore, the
drywall corner finishing device components will be described first, followed
by a
description of the window wrap constructed using the drywall corner finishing
device
components.
Turning to FIGS. 1 and 1a, the left 102 and right 104 wings of the drywall
corner finishing device component are attached to a flexible center joint 100
and
extend outwardly therefrom to a distal edge 110. In FIG. 1 a, the wings 102,
104 have
a front surface 106 and a rear surface 108. The front surface 106 and rear
surface
108 extend outwardly beyond the outer strut 110 of the wings 102, 104. When
the
drywall corner finishing device covers either an inside corner or an outside
corner,
the rear surface 108 of the device is juxtaposed to the framing of an interior
wall
while the front surface 106 faces out into the room, contiguous with the
surface of
the drywall panels forming the wall. In the embodiment shown in FIG. 1, wing
104
only has a front surface 106. The front surface 106 may be covered with a
layer of
primer 300 as shown in FIG. 3 so that any paint or wall covering that is
eventually
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used to decorate the wall will adhere easily. Alternatively, the front surface
106 may
have an adhesive laminate 400 attached to it as shown in
FIG. 4.
In the preferred embqdiment of the drywall corner finishing device, a laminate
400 is used on the front surface 106. For best results the laminate should
have
extensible or flexible properties to it sa that the laminate does not crack
when the
device is bent at the flexible joint, but otherwise have surface
characteristics as
similar to those of drywall panels. Through extensive testing, best results
were had
using a paper laminate manufactured by Fibermark of Fitchburg, Massachusetts,
and sold under product number X41693. It is understood that disclosure of this
particular laminate does not limit the invention to use of only this laminate
nor
exclude the use of other laminates which are also suitable for use with the
device.
In the preferred embodiment, the paper laminate is affixed to the device by a
pressure sensitive adhesive, which remains pliable after application and
during
normal operating conditions of the device. Through extensive testing, best
results
were had using an adhesive manufactured by Worthern Industries of Nashua, New
Hampshire, and sold under product number Nylco E-68. This adhesive provides a
fusion level bond between the device and the laminate, which greatly reduces
the
tendency of the laminate to separate from the device. Other suitable adhesives
include those which do not harden nor negate the extensible properties of the
applied paper laminate.
The device itself may be extruded using various materials. In the preferred
embodiment of the invention, a PVC plastic is used, manufactured by Veka, Inc.
of
Fombell, Pennsylvania, and sold under product number X-15.
It is understood that disclosure of this particular material does not limit
the invention
to use of only this material nor exclude the use of other materials which are
also
suitable for use with the device.
The structure of the drywall corner finishing device component is more clearly
seen in FIG. 2. The flexible center joint 100 preferably extends from the
front
surface of each wing to the other and is either tapered or has parallel walls,
but it is
to be expressly understood that any joint shape, such as actuate, V-shaped, U-
shaped, C-shaped, etc. can be used that allows the device to bend through a
variety
of angles at the center joint 100. The center joint 100 extends along an axis
that
extends linearly to form a corner or edge.
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The tapered joint 101 embodiment of the flexible joint has a front surface
which extends parallel to the front surface 106 of the device. The rear
surface of the
tapered joint 101 tapers inwardly from the two wings, toward the front
surface. This
allows for a sharp, clean corner to form along the front surface of the
tapered joint
101 here it is the thinnest, when the device is bent along the joint, as can
be more
clearly seen in F1G. 6.
The tapered joint 101 embodiment of the flexible joint may be used to form
both inside and outside corners.
A number of struts 206 separate the rear surface 108 of each wing 102, 104
from the front surface 106 of each wing 102, 104. In the embodiments shown in
FIGS. 1 a, 1 b and 2, the pattern of struts 206 provides stability to the
structure of the
corner device and also allows the device to be folded around outside corners,
as
discussed in more detail below. It will be obvious to one skilled in the art
that the
pattern of struts 206 shown in FIGS. 1 and 2 is not the only pattern that will
provide
these features of stability and folding and that other patterns would be
suitable and
are to be included in the present invention.
The edge 202 of the rear surface 108 extends beyond the edge 200 of the
front surface 106. The outer portion 204 of the front surface 106 tapers
slightly
toward the rear surface 108 so that, as discussed in more detail below, the
edge of a
drywall panel can be placed in the space 114 between the front surface 106 and
the
rear surface 108 such that the edge 202 of the rear surface 108 and the edge
200 of
the front surface 106 are in close opposition to the drywall panel.
A flexible flange joint 113 is located at the intersection of the rear surface
108
and the outer edge 110. The rear surface 108 may then be bent at the flexible
flange joint 113 thereby allowing the rear surface flange 112 to pivot about
the
flexible flange joint 113 to adjust the space 114 between the front surface
106 and
rear surface 108 to fit various thickness drywall panels.
It is to be understood that types of flexible flange joints 113 other than
that
illustrated in FIGS. 1 - 13 can be used in the present invention and that the
present
invention includes all types and designs of joints that provide the above-
described
bending and pivoting.
In the preferred embodiment of the device, the front surface 106 and the rear
surface 108 taper slightly towards each other, as they extend towards the
distal ends
of each wing 102, 104. This tapering of the wings 102, 104 helps to facilitate
a
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smooth transition from the surfaces of the device and the surfaces of the
inserted
drywall panels.
FIG. 5 illustrates the drywall corner finishing device bent at the center
joint
100, at a 90°angle, as shown by arrow 500, to form an outside corner.
Four drywall
corner finishing devices are needed, each formed in a 90° outside
corner, to be used
as the jamb and sill portions of the window wrap. The four portions of the
window
wrap consist of two side jamb portions, a head sill portion, and a bottom sill
portion.
As FIG. 7 shows, the ends of each portion are cut at an angle to form a
90°mitered joint between the ends of each joined portion. In this
configuration, the
wings of the drywall corner finishing device now form a wall extension 302 and
a
jamb/siil extension 304.
FIGS. 8-12 show the four jamb/sill portions assembled together to form the
window wrap. The portions are joined at each miter joint 306. While the jamb
sill
portions may be joined together in any fashion, the preferred connection is
with a
mitered-joint. The mitered joint may be fastened together by a fastener or
adhesive.
However, the preferred means of joining each miter jointed end is to fuse or
weld
each end to each other. By doing this, an air and water tight seal is formed
between
each adjacent portion. The wall extensions 302 of each portion all extend
outwardly
from the center joint and lie in the same plane. The jamb/sill extensions 304
of each
portion now all extend rearward from the center joint, each extension
perpendicular
to the adjacent extension.
Thus, the above-described window wrap may be manufactured to
accommodate any size window frame simply by varying the lengths of jamb
portions
and sill portions joined together. The jamb/sill extensions may also be varied
to
accommodate any desired jamb/sill depth. If the desired jamb/sill depth is
shallower
than the length of the jamb/sill extension, the extension may be cut to the
proper
depth. However, if the desired jamb/sill depth is deeper than the length of
the
jamb/sill extension, a piece of drywall may be inserted into jamb/sill
extension to
provide the desired depth.
The window wrap may then be inserted, as a unit, directly into the rough
window frame. It is preferred that an adhesive be used between the rear
surface
202 of the wall extensions 302 and the rough frame. However, a trim channel or
caulk my also be used between the window wrap and the rough window frame. The
use of adhesive allows for settlement of the window wrap, reduces the chance
of
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cracking at the corners of the window wrap, and provides an almost airtight
seal
between the window wrap and the frame. The drywall panels on the framing wall
around the window frame may then be inserted into the space 114 of the wall
extension 302 of the window wrap.
As an example, in FIG. 13, the extension of the window wrap is attached to
the wall framing 800 by use of nails 806. The window wrap preferably is made
of
plastic soft enough to permit the nails 806 to be driven through the flange
112 of the
rear surface 108 without the need for pre-formed holes. It is to be expressly
understood that other methods such as the use of screws, bolts, adhesive, etc.
will
be equally efficacious in attaching the window wrap to the supporting members
of
the framing. The attachment location of the window wrap and the positions of
the
nails 806 can be varied to enable the window wrap to correct inequalities that
may
exist within the framing and from one framing member 800 to the next. If
necessary,
shims may be placed behind the window wrap before it is attached by nails 806
or
affixed by an adhesive. The edges of the drywall panels 804 are inserted into
the
spaces 114 between the front surface 106 and rear surface 108, such that the
edges
of the drywall panels 804 abut the outer strut 110 of the wings 102, 104. It
can be
seen in FIG. 13 that the spaces 114 between the front surface 106 and rear
surface
108 are just large enough to accommodate the drywall panels 804 and that the
front
surface 106 and rear surface 108 are closely juxtaposed to the drywall panels
804.
The drywall panels 804 thus hide the nails 806. The drywall panels 804 are
attached
to the framing 800 in the usual fashion.
As FIG. 13 shows, plaster 1300 is then applied to the tapered distal portion
204 of the front surface 106 and the tapered edge of the drywall panel 804 to
hide
the edge 200 and provide a smooth, level surface. Because plaster 1300 is
applied
only to the tapered portion 204 of the finishing device, difficulties inherent
in
plastering within corners are avoided. Such difficulties include, among
others, the
difficulty in maneuvering a plaster trowel within a corner, the skill need to
produce a
perfectly straight edge where the two sides of the corner meet, and the need
for
several layers of plaster 1300 to completely hide the joint between the window
wrap
and the drywall or to correct the inequalities resulting from mis-sized, mis-
placed, or
warped framing members, with each layer requiring considerable time to dry.
Once
plaster 1300 has been applied, the surface of the wall or sill/jamb can be
finished by
painting, wallpapering, or any other method desired. The primer 300 bonded to
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front surface 106 enables paint or other wall coverings to adhere to the front
surface
106 of the finishing device. In another embodiment, a laminate 400 can be
adhesively affixed to the front surface 106 to provide a surface for
subsequent
painting.
Plaster alternatives may also be used to hide the edge 200. Plaster
alternatives include, but are not limited to stucco, stucco plasters,
synthetic stucco
and cement siding products.
Alternatively, the window wrap may be installed without applying plaster
between the edges of the window wrap and the drywall, to hide the window wrap
edges. The window wrap may then be painted or covered in any way desired,
providing a visual border around the border. Another alternative is to hide
the
window wrap by placing molding over the edges of the window wrap and drywall.
FIG. 14(a) illustrates the wall or jamb/sill extension in a resting position.
When'/2" drywall panel 1500 is inserted into space 114 between the edges 200,
202
as shown in FIG. 14(b), the drywall panel 1500 is held against the rear
surface
flange by edge 200 as shown in FIG. 14(c).
FIG. 15(a) illustrates 5/8" drywall panel 1600 inserted into space 114.
between
the edges 200, 202. With the greater thickness drywall panel 1600, rear
surface
flange 112 pivots at flexible flange joint 113, away from the front surface
106. Front
surface 106 remains relatively straight due to outer strut 110, which extends
from the
front surface 106 of the extension away from the end of each wing, to the rear
surface. Another consideration which helps to allow the front surface 106 to
remain
relatively straight while the rear surface flange 112 pivots, is that the wall
thickness
of the rear surface 108 is slightly thinner than that of the front surface
106. This
effect could also be facilitated in other'ways such as reducing the wall
thickness of
the rear surface 108 where it intersects the outer strut 110 at the flexible
flange joint
113, thereby weakening the immediate area, allowing the flange joint 113 to
pivot
more easily.
FIG. 15(b) illustrates rear surface flange 112 held in place adjacent drywall
panel 1600 once the extension and drywall panel 1600 are installed, as further
shown in FIG. 16.
Best results when using the device were found when an adhesive was used to
affix the inside surface of space 114 of an extension with the drywall.
Preferably a
fusion bond adhesive is used. Two adhesives which were found to be suitable
for
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this application are product number PL Premium manufactured by OSI Sealants of
Mentor, Ohio and product number F2100 in combination with product number
F2100A, manufactured by ITW Foam Seal of Oxford, Michigan. It is understood
that
disclosure of these particular adhesives does not limit the invention to use
of only
these adhesives nor exclude the use of other adhesives which are also suitable
for
use with the device.
FIG. 16 illustrates how the extension of the window wrap is installed with a
5/8" panel 1600. A block 1700 may be used to keep the device and the drywall
panel 1600 parallel with the framing surface which the drywall panel 1600 is
attached. The block 1700 is affixed to the rear surface 108 of the extension.
The
window wrap and drywall panel 1600 are affixed to the framing surface by nails
1702
or some other fastening device. When the nails 1702 are fastened into the
framing
surface, the rear surface flange 112 is sandwiched between and adjacent to the
framing surface and the drywall panel 1600. Thus, this window wrap can be used
for
drywall panels that are thicker than the thickness of the device.
The window wrap of the present invention may be modified in several ways.
First, the window wrap may be constructed of a solid material or a material
other
than plastic. Second, the drywall corner finishing device component may be
extruded with a 90° bend at the center between the two wings, the joint
between the
two being rigid. While this would save the step of bending the device between
the
extrusion and the angled-cut steps, it is easier to store and transport the
device,
before the jamblsill portions are connected together when the device is flat.
Third, if
added insulation in the window wrap is desired, insulation may be placed
between
the struts before each portion is joined together. Fourth, each of the outer
portions
of front and rear surfaces of each extension, which are adjacent the outer
edges,
and are free of reinforcing structure, may be excluded. Fifth, each of the
jamb and
sill portions may be connected together other than by a mitered joint or other
than by
fusing or welding the portions together. Sixth, each of the wall or jamb/sill
extensions may be constructing using only a single surface. Lastly, the jamb
and sill
portions may be connected together at angles other than 90° to each
other, allowing
for use with different shaped window frames.
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