CA1328374C - Adjustable window building kit - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

This invention provides an improved set of extrusions whereby a window can be assembled on-site from lengths of extrusion, rather than pre-made in a work shop. By the use of at least two extrusions, one of which is directly attached to the window aperture, for each of the sill, jambs, and head piece, irregularities in and warping of the window framed aperture are accommodated by inserting shims either between these extrusions, or between the extrusions and the window aperture. The shims are channel-like extrusions, which, on assembly, are adjusted to the required thickness by cutting the side walls of the channel. After the window is assembled into the aperture, any shims used are hidden by the extrusions.

Description

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This invention relates to a kit and to a method of on-site construction, or reconstruction, of windows utilizing panes which can be displaced either horizontally or vertically. More particularly, this invention is concerned with windows in which the glass panes are unframed and are installed in slots provided in the fixed parts of the window.

It is known to construct window fenestration systems from a plurality of metal, typically aluminium, or plastic, typically PVC, extrusions of a greater or lesser degree of complexity. Generally several different extrusions are needed in order to assemble a complete window. Furthermore, these complex shapes are not such as to permit on-site assembly of the window and its framing, more or less as the window unit is being installed into the aperture prepared for it.
Generally speaking the window, be it either for new construction or for replacement purposes, is delivered effectively fully assembled to the site. Usually the only on-site assembly needed is to attach external hardware such as pulls and locks. Such frames also use a single piece extrusion for each of the sill, jambs and head piece.

There is one inherent disadvantage with this procedure which although perhaps not apparently important for new construction, nevertheless does o~cur. Where replacement construction is concerned, it is a major problem. The disadvantage is that such a preassembled window has to be made to predetermined dimensions. For new construction it should be possible to ensure that the aperture provided for the window is of the correct size, be this in timber frame construction or any other method. But mistakes do happen, and fenestration apertures do get framed the wrong size. Furthermore, in little modern timber frame construction is the timber being used as true as one could desire. Thus although the framed aperture may be of nominally the correct dimensions, if the wood is warped, the actual framed dimensions will not be the same as the nominally correct ones.
Whilst this does also occur with replacement window construction, there is then the added complication that sometimes the actual framed aperture cannot be determined until the old window has been removed.
There is consequently a need for a window construction system that -. : - , ~ . : , . ~ - , -will accommodate these dimensional problems, particularly if such a system could provide for on-site assembly of the window.

This invention seeks to provide such a window construction system, assembled from a plurality of mutually cooperating extrusions, which, due to ~heir essentially simple nature, can be cut and assembled directly into the aperture framed for the window on site. A
particular feature of this invention is that these various extrusions cooperate together to "hide" any shims required to provide a substantially linear frame with right angle corners into which the glass is fitted.

Thus in its broadest embodiment t ~ s invention provides a window framing system adapted to receive at least one window pane comprising a plurality of mutually cooperating extrusions, wherein each of the four members making up the perimeter of the frame, comprising a sill, two ~ambs, and a head piece, comprise at least two members, including a first member attached directly to the window aperture and a second member attached in cooperating relationship to the first member, and wherein any shims necessitated by inaccuracies in the window aperture are fixedly inserted between either the first member and the aperture face, or between the first and second member.

In a narrower broad embodiment this invention provides a window framing system adapted to receive a plurality of horizontally or vertically sliding window panes comprising a plurality of mutually cooperating extrusions, wherein each of the four members making up the perlmeter of the frame, comprising a sill, two ~ambs, and a head piece, comprise at least two members, including a fir6t member attached directly to the window aperture and a second member attached ~ -in cooperating relationship to the first member, and wherein any shims necessitated by inaccuracies in the window aperture are fixedly inserted between either the first member and the aperture face, or between the first and second member.

ln a preferred embodiment, the window glazing includes two separate sets of window paneR, thus providing double glazing.

In a further preferred embodiment, each of the jambs comprises twomembers, in which the first member is of a generally channel shaped cross section with a flat base area, which is attached to the window aperture, and at least two upstanding legs, and a second member having on one face slots adapted to receive the legs and on its other face at least one slot adapted to receive a pane of glass.

In another preferred embodiment, the head piece comprises three members, in which the first member is of a generally channel shaped cross section with a flat base area, which is attached to the window aperture, and two upstanding legs; the second member is of a generally channel shaped cross section with a flat base area and a doubled outside wall, the outer outside wall extending toward the base area of the channel to provide a slot continuous and contiguous with the outside wall of the channel, adapted to receive the legs of the first member ~so that the second member nests inside the first member in a base to base relationship); and a third member adapted to fit across the legs of the second member (to convert the channel into a box member) and having on its outer face at least one slot adapted to receive a pane of glass.

In a variation of this embodiment, the second member, although extruded for simplicity in a simple channel shape, is provided with a longitudinal break line in its base area, and is separated into two parts before attachment to each leg of the first member. This has the advantages both of making installation easier, and of economy of material. The base area is made wide enough to provide an adequate face width to bear against any needed shims.

In an additional preferred embodiment the sill comprises three members, in which the first member is of a generally L-shaped cross section, one limb of which is fixedly attached to the window aperture; a second member comprising a generally wedge shaped box member, the thinner end of which is the outer (weather) end of the sill, having a single slot proximate its thicker end adapted to receive the upstanding limb of the first member, and a third member : ~ , i328374 adapted to be attached to the second member having on its upper face at least one slot adapted to receive a pane of glass.

In this embodiment of the sill, any shims needed are fixedly attached between either the first member and the second member, or between the second member and the window aperture. The same shims as those described for the jambs and head piece are preferred.

In an alternative additional preferred sill embodiment, in a similar fashion to the jamb and head piece arrangements described above, a generally channel shaped member can be used for the first member, together with a second receiving slot in the underside of the second member.

In all of these embodiments, any shims necessitated by poor alignment of the window aperture are inserted fixedly between the first and second members. Preferably these shims comprise a channel like member having a flat base and two upstanding legs, which can be adjusted for thickness by trimming the legs, and is installed substantially at right angles to the first member, and with the second member abutting its flat base.

Thus it can be seen that this multi part construction for the sill, jamb, and head members provides two advantages. First, the flexibility of each of the first members accommodates variances out of t~ue of the window aperture. Second, the interconnection of the pairs of first and second members automatically provides a draft and heat seal between the portions of the window frame which have to be substantially straight (as otherwise the window panes will jam) and the framing of the window aperture, which generally will not be substantially straight. At present such gaps have to be sealed by other means, such as forcing glass wool into them. If these gaps are small - as they should be - this is an awkward and time consuming operation. Alternatively, these gaps can be caulked, but then as the gap can be up to about 15 cm deep (many modern houses are framed in so-called "2x6" lumber) it can use up an inordinate amount of caulking.

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This form of construction can be used for any type of window that can be assembled from a set of extruded moldings. It therefore appears to be most useful for a window of the sliding pane type, and that form of window is described in more detail below. Nevertheless it will be apparent from that description that the extrusions used herein can easily be modified to accept other glazing systems which do not use a more or less free-standing glass pane. These will include thermopanes, fixed windows, and windows which swing about a pivot to open. It is also contemplated to provide within a single window opening windows of two different types, such as a fixed pane and a wind-open window, separated by an intermediate joint jamb. For situations such as these the extrusions described below can still be used, with other, extra, extrusions attached to them (into the slots provided for the glazing) to provide the needed anchorages for other glazing systems.

The invention will now be described by way of a discussion of the particular embodiments of the attached drawings in which:

Figure 1 shows in exaggerated form a timber framed window aperture;

Figure 2 shows a sill anchor and seal strip;

Figure 3 shows a sill member;

Figure 4 shows an adjustable shimming member;

Figure S shows a sill track member;

Figure 6 shows a jamb holder;

Figure 7 shows a first jamb member;

Figure 8 shows a second jamb member;

Figure 9 shows an adjustable head piece;

~328374 Figure 10 shows a head track retaining member; and i Figure 11 shows a head track member.

In Figures 2 to 11, cross sections are shown for the various members depicted, except for the view in Figure 4B.

In describing these figures, it is easiest to describe the sequence of steps taken in creating a window. In this embodiment, all of the extrusions used are made in PVC.

Inspection of the window aperture shows that, as can be seen in Figure 1, although the framing, 1, provided in the wall is generally square, more detailed examination shows that a truly rectangular shape, shown dotted as 3, is slightly smaller. Consequently, a plurality of shims, typical ones of which are shown placed at 2, will -be needed. It is worthwhile to note at this stage that if a j conventional pre-made window were being used, all that could be done I would be to provide wedging shims on all four sides around a window ¦ fitting the dimensions implied by the line 3. In assembling a window i according to the present invention, a sill anchor and seal strip, as shown in Figure 2, is attached across the lower member, ls, of the framing 1. For a new construction, this will be the window aperture framing; for replacement construction, this may be the original framing, or it may be an existing sill, or other trim piece.
Similarly, when reconstructing, existing window wood if sound will be retained, the jambs and head piece being attached to it.
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The placement of the anchor and seal strip is carefully selected, since its location determines the placemen~ of the whole window in the window aperture. It is located into the window framing so that the window will be aligned substantially parallel to the outside wall, and with the outer thinner edge of the sill located to ensure rain run-off. The strip comprises a generally L-shaped length, with one limb 5 being shorter than the other, 4. The anchor strip is installed with the shorter limb upwards. It is nailed, stapled, or attached by other suitable means to the window aperture.

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The next step is to install the sill second member, as shown in Figure 3. This is a box member, of a generally wedge shaped cross section, as shown at 10, with suitable internal strengthening ribs.
The number and placement of the ribs will in large part be determined by the overall depth of the sill, and the nature of the window. A
double glazed window requires a stronger sill to support the greater weight of glass when compared to a single glazed window. The sill member is provided with a locating slot 6 which engages the upstanding limb 5 of the anchor strip. It is also provided with a slot on its front edge, 8, the purpose of which will be discussed below, an anchor slot 9 and upstanding ridge 7. The base of the sill is recessed at 53 to provide clearance over the anchor strip in areas where no shimming is needed.

In an alternative embodiment, a channel member is used as the anchor strip, and the sill member is provided with a second slot, as shown dotted at 54, into which the other upstanding leg of the channel member is inserted. As this method of construction is more complex, the simpler system described above is preferred. The use of an anchoring channel serves to hide any shims needed. In the absence of such a channel, a trim piece is inserted in the slot 8, to hide any shims and to provide a weather seal between the sill and the wall.

The cut length of sill 10 is ad~usted for level with shims.
Preferably, these are as shown in Figure 4. The extrusion can be seen to have a flat face, 13, and legs 11 and 12. A suitable length is cut and placed with the flat face upwards and substantially at a rlght angle to the length of the sill. Generally the shim will extend from near the vertical face of the llmb 5 of the anchor and seal strip to close to the outer edge of the wall. Using a sharp ~nlfe, the legs are ad~usted to get the sill 10 levelled. Suitably, where needed, shims will be about 15 cm apart. They can be nailed or otherwise fixed in place. The s~ll is then placed over the anchor, with limb 5 engaging slot 6. If desired, caulking can be laid (not shown) under the sill before it is finally placed.

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It can thus be seen that the angle trim provides a continuous inner wall and seal for the sill, and which also allows enough vertical adjustment to level the sill. As a last step, a suitable external trim strip will be fitted into the slot 8 (not shown in the figures).

Onto the sill member 10 is installed a suitable length of the sill track member, as shown in Figure 5. This is adapted to be a snap fit onto the sill member 10. The downwardly projecting flexible rib 19 i9 inserted into the slot 9, and the outer wall 18 locates closely inside the rib 7. Although not shown in the drawings, it is desirable to provide cooperating drainage apertures in both of the rib 7 and the wall 18, together with the other downwardly pro~ecting support ribs shown on the sill track. This can be done in several ways; the provision of thinned 'knock out' portions coupled with a judicious selection of extrusion cutting points is convenient. If preferred, insertion of the sill track can be left until the main parts of the jambs have been installed.

! The first step toward assembling the jambs i8 to fixedly insert in place aligned vertically from and to coopera~e with the sill member , two ~amb holders, a6 shown in Figure 6, to each of the sides 1; of j the framing 1. These are installed with the recess 52 on the outer, weather, side of the window. This recess is provided to give clearance for a trim strip which can be placed at the same time. The anchor angle of Figure 2 can be conveniently used for this purpose.
Both the trim, if used, and the ~amb holder are nailed, for example, into the window framing. Suitable lengths of the jamb members are then offered up, but not inserted onto, these jamb holders and checked for verticality in the plane of the window pane. Any needed shims, using the procedure outlined above, are inserted into the flat ~ base 15A of the ~amb holder. The ~amb members can then be secured in j place, with the legs 16, desirably provided with felt seals for air tightness 17, entering the slots defined by ribs 41,42; 43,44;
48,49; and 50,51 of the jamb members shown in Figures 7 and 8.
These members comprise a left and right pair, Figure 7 being the 1 left, and Figure 8 belng the right hand; if desired, these can be! reversed, as both the head and sill track members have four ~ - 8 -G
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The head part of the window is assembled in a similar fashion.
First, a suitable length of the adjustable head piece shown in Figure 9 is nailed in place, in cooperating alignment with the top ends of the ~amb holders. This is placed with the recess 25 to the weather side of the window, so as to allow insertion of a trim piece. Again, the anchor strip of Figure 2 can be used for this, or, where building codes require, an overhead drip angle trim can be inserted. The head track retaining member of Figure 10 is conveniently extruded as a single piece. In use it is snapped apart along the indent 31 to provide two separate head track retainers. These can be seen to be interchangeable, and are attached over the downwardly projecting legs 21 and 22 (after installation) of the ad~ustable head piece. As with the ~ambs, these retainers are first offered up to determine any required shim thicknesses, again using the shims of Figure 4, which are placed between the flat part 20 at the base of the channel of the ad~ustable head piece and the parts 32 and 33 of each of the head track retainers. The shims are nailed or otherwise secured into place, and will generally extend substantially across the full width of the channel of Figure 9. The head track retainers are also put in place onto the ribs 21 and 22, which enter into the gap provided between legs 26,27 and sidewalls 28,29 in the head track retaining members. The head track retainers are either separately nailed, or held in place with the same nails used to retain the shims in place.
The ends of the head track retainers are also cut away suitably at 36 and 37, at each end, to provide clearance over the jamb holders. The third pro~ectlng leg 23 of the ad~ustable head piece, together with ~ -the thinner end lip 24, serves to provide a water tight seal across the width of the head piece, since lip 24 bears down onto the outer head track retainer when it is pushed onto the leg 22.

Finally, a suitable length of head track, as shown in Figure 11 is inserted into the retaining members, wherein it is a snap-in fit between the ribs 34,35 and the base portions 32,33 of the head track _ g _ ,~'`' :
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~ ' .. ', ' " ', . ' "' ' .1 . . ' ' ~ ,''" " ': , , ' ' ' ~' ' ' ' - ' ' ' ' : ' ' ' . . ' .. ' :: : . .'' ' ,' retaining members (it is to be noted that the drawings are not to a uniform scale), and the left and right jambs, mentioned previously, are put into place. The sill track member, if not placed earlier, will be put in place before the jambs are finally installed. The window frame is now ready to receive its glazing. This will comprise suitably cut panes fitted directly into the head and sill tracks, utilizing the greater slot depth in the head tracks. These tracks can be provided with felt or other sealing means, and also, at the sill, with adequate condensation drainage. In the extrusions shown provision is made for double glazing, but this system can be modified for single glazing if desired. Similarly, the extrusions can be modified to incorporate insect screens, as desired.

Certain modifications will be made in this system if it is being used to replace an existing window rather than to provide a new one. In that case there will usually be a projecting sill, generally of wood, already present. The main sill members are then placed onto this existing sill, and, if deemed necessary, a suitable cap molding applied over it. Similarly, a top drip molding will also then generally be present, and hence only minimal trim will be needed to be fitted into the recesses provided in the jamb holders (52) and the ad~ustable hesd pieces (25).

Where a window is being installed into new construction, then in some places the sill is not required to project. As noted above, the slot 8 can then be used to provide a simple weather seal by using the anchor strip of Figure 2 overlapping with existing siding, inserted into the slot 8.

In the drawings the various mutually cooperating parts, e.g. the limb 5 and the slot 6, are shown plain, for simplicity. In practice, these parts will be modified with restraint and retaining means so that once assembled they cannot easily be separated. Thus the limb 5 can be provided with barbs, and the slot 6 with inner cooperating ridges. This is especially important for the jambs, as this form of anchorage is all that is needed to hold it in place. Similarly for the sill the only location needed i8 the anchor piece as in Figure 2 ,,4^' , ~ ' ' ' ' , .. ' , ,''' ,: '' ' ,.
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as the combination of the jambs and the simple weight of the window panes is enough to keep it in place. This avoids having to make holes through these pieces to anchor them, which would be difficult to seal. In a similar way, where relevant or necessary, subsidiary seals can be provided to ensure that the window is weather tight.
This will include the seals shown in Figures 7 and 8 for the glass into the jambs, and the placement of conventional fibre or the like seals in both the sill and head tracks. It is also conventional practice to provide the central edges of the glass panes with a meeting rail and a pull rail, and to provide the window when assembled with window locks.

Further, unless carefully ground edges are used, it is desirable to provide the glass panes with snap-on edges, to protect the sill track at least from being scored or gouged by sharp glass edges.
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The extrusions used herein are hollow shapes; when deemed desirable~
or when building codes so require, these cavities can be filled with suitable thermal insulation, for example foam or polystyrene strips pre-r~de and cut to fit the aperture in question.

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Claims (11)

1. A window framing system, adapted to receive a plurality of horizontally or vertically sliding window panes, comprising a plurality of mutually cooperating extrusions, wherein each of the four extruded members making up the perimeter of the frame, consisting of a sill, two jambs, and a head piece, comprises at least two members, including a first member for direct attachment to the window aperture and a second member attached in cooperating relationship to the first member, wherein any shims necessitated by inaccuracies in the window aperture are fixedly inserted between the first member and the second member, and wherein any required shims comprise an extruded channel like member having a flat base and two upstanding legs adapted to be installed with its length transverse of the second member, with its legs cut to provide the required shim thickness, and with its flat base bearing against a cooperating flat surface of the second member.

2. A window framing system, adapted to receive a plurality of horizontally or vertically sliding window panes, comprising a plurality of mutually cooperating extrusions, wherein each of the four extruded members making up the perimeter of the frame, consisting of a sill, two jambs, and a head piece, comprises at least two members, including a first member for direct attachment to the window aperture and a second member attached in cooperating relationship to the first member, wherein any shims necessitated by inaccuracies in the window aperture are fixedly inserted between the first member and the window aperture face, and wherein any required shims comprise an extruded channel like member having a flat base and two upstanding legs adapted to be installed with its length transverse of the second member, with its legs cut to provide the required shim thickness, and with its flat base bearing against a cooperating flat surface of the second member.

3. A window framing system according to claim 1 or 2 adapted to receive two independant sets of window panes to provide double glazing.

4. A window framing system according to claim 1 or 2 wherein all of the extrusions used are fabricated from PVC.

5. A window framing system according to claim 1 or 2 wherein each of the jambs comprises two members, in which the first member is of generally channel shaped cross-section with a flat base area and two parallel upstanding legs; in which the flat base area is for direct attachment to the window framing; and in which the second member has in one face two laterally spaced parallel slots adapted to receive the upstanding legs of the first member, and in its other face at least one slot adapted to receive a pane of glass.

6. A window framing system according to claim 1 or 2 wherein the head piece comprises three members, in which the first member is of a generally channel shaped cross section with a flat base area and two parallel upstanding legs in which the flat base area is for direct attachment to the window framing; the second member comprises a further channel shaped cross section having a doubled outside wall, the outer outside walls extending from the tip of the leg toward the base of the second member adapted to receive the legs of the first member, and a third member adapted to fit engageably into the gap between the legs of the second member, and having on its outer face at least one slot adapted to receive a pane of glass.

7. A window framing system according to claim 1 or 2 wherein the second member comprises a pair of sub-members, each of which is attached to each leg of the first member, and each of which has base portions extending towards each other in the gap between the legs of the first member proximate the base of the first member.

8. A window framing system according to claim 1 or 2 wherein the sill comprises three members, in which the first member is of a generally channel shaped cross section with a flat base area and two substantially parallel upstanding legs, in which the flat base area is for direct attachment to the window framing; the second member comprises a generally wedge shaped box member having slots in its base adapted to receive the upstanding legs of the first member, one of which slots is proximate the thicker end of the general wedge shape of the second member, and the third member has one face adapted to fit onto and engage with the sloped face of the generally wedge shaped second member, and having on its outer face at least one slot adapted to receive a pane of glass.

9. A window framing system according to claim 1 or 2 wherein the sill comprises three members, in which the first member is of a generally L-shaped cross section, one limb of which is for direct attachment to the window framing; the second member comprises a generally wedge shaped box member having a longitudinal slot in its base proximate its thicker edge adapted to receive the other limb of the first member, and the third member has one face adapted to fit onto and engage with the sloped face of the generally wedge shaped second member, and having on its other face at least one slot adapted to receive a pane of glass.

10. A window framing system adapted to receive a plurality of horizontally or vertically sliding window panes, comprising in combination:
(a) a sill comprising three members, in which the first member is of a generally L-shaped cross section, one limb of which is for direct attachment to the window framing; the second member is a generally wedge shaped box member having a longitudinal slot in its base proximate its thicker edge adapted to receive the other limb of the first member, and the third member has one face adapted to fit onto and engage with the sloped face of the generally wedge shaped second member, and having on its other face a plurality of slots adapted to receive panes of glass constituting a double glazing system;
(b) a right and a left jamb, each of which comprises two members, in which the first member is of generally channel shaped cross-section with a flat base area and two parallel upstanding legs; in which the flat base area is for direct attachment to the window framing; and in which the second member has in one face two laterally spaced parallel slots adapted to receive the upstanding legs of the first member, and in its other face a plurality of slots adapted to receive panes of glass constituting a double glazing system;
(c) a head piece comprising three members in which the first member is of a generally channel shaped cross section with a flat base area and two upstanding parallel legs in which the flat base area is for direct attachment to the window framing;
the second member comprises a pair of sub members, each of which is attached to each leg of the first member, wherein each sub member has a base portion extending toward the center of the base of the first member in the gap between the legs of the first member, and a doubled wall portion which is adapted to receive a leg of the first member; and a third member adapted to fit engageably into the gap between the two sub members constituting the second member having on its outer face a plurality of slots adapted to receive panes of glass constituting a double glazing system;
(d) where required, shims comprising a channel section, comprising a substantially flat base with two upstanding leg portions, placed substantially perpendicularly to the first members and extending for a substantial proportion of the width of the second member, wherein the second member bears on the flat base of the channel section, the legs of which are of a height to provide the required shim thickness; and wherein all of the sill, jamb, head piece, and, when used, shims, are PVC extrusions.

11. A kit for a window frame comprising extrusion lengths in PVC
adapted to provide in combination:

(a) a sill comprising three members, in which the first member is of a generally L-shaped cross section, one limb of which is for direct attachment to the window framing; the second member comprises a generally wedge shaped box member having a longitudinal slot in its base proximate its thicker edge adapted to receive the other limb of the first member, and the third member has one face adapted to fit onto and engage with the sloped face of the generally wedge shaped second member, and having on its other face four slots adapted to receive four panes of glass constituting a double glazing system;
(b) a right and a left jamb, each of which comprises two members, in which the first member is of generally channel shaped cross-section with a flat base area and two parallel upstanding legs; in which the flat base area is for direct attachment to the window framing; and in which the second member has in one face two laterally spaced parallel slots adapted to receive the upstanding legs of the first member, and in its other face two slots adapted to receive two panes of glass constituting a double glazing system;
(c) a head piece comprising three members in which the first member is of a generally channel shaped cross section with a flat base area and two upstanding parallel legs in which the flat base area is for direct attachment to the window framing;
the second member comprises a pair of sub members, each of which is attached to each leg of the first member, wherein each sub member has a base portion extending toward the center of the base of the first member in the gap between the legs of the first member, and a doubled wall portion which is adapted to receive a leg of the first member; and a third member adapted to fit engageably into the gap between the two sub members constituting the second member having on its outer face four slots adapted to receive four panes of glass constituting a double glazing system;
and (d) where required, shims comprising a channel section, comprising a substantially flat base with two upstanding leg portions, placed substantially perpendicularly to the first members and extending for a substantial proportion of the width of the second member, wherein the second member bears on the flat base of the channel section, the legs of which are of a height to provide the required shim thickness.