AU712941B2 - Fixing windows in window openings - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): DOWELL AUSTRALIA LIMITED A.C.N. 004 437 898 Invention Title: FIXING WINDOWS IN WINDOW OPENINGS The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 FIXING WINDOWS IN WINDOW OPENINGS FIELD OF THE INVENTION This invention relates to fixing windows in window openings and has particular although not exclusive application in connection with concrete formed buildings.

Throughout the specification the terms window or window frame or the like are to embrace not only windows but also the fitting of doors or other similar products into openings in walls of buildings.

DESCRIPTION OF PRIOR ART Hitherto, window frames have been fitted into window openings in buildings such as concrete formed buildings.

Reference should be made to Figure 1 herein which shows a typical prior art installation. This will be described in more detail in due course. The window frame is held in the window opening by bracket members which are, in turn, fastened directly into the wall surfaces of the window opening. Usually an outer or weather side bracket is first fitted in place and then the window frame butted up to that bracket. A sealant material is applied to the abutting faces. A further bracket is then applied to the inside of the installation to retain the window frame within the 25 window opening. A problem with such installations is that firstly, considerable stresses are placed on the window as a result of thermal expansion and/or contraction.

Secondly, the window opening may change in size because of movement in the building itself. Such change in the a a..

building itself can occur as a result of thermal influences or as a result of structural influences.

A problem with such prior art installations is that the sealant eventually breaks down or ruptures because of H:\Gale\Keep\speci\CAP.Dowell.P21377.doc 1/08/97 3 this movement. In practice, sealant such as silicone based sealants are design specified to experience no more than movement relative to the thickness of the sealant.

Whilst in theory, the space between the brackets in the prior art installations can be increased thereby increasing the thickness of the sealant, this is difficult to accurately control on site due to inexperienced installation trades persons and also due to the non ability to predetermine the extent or depth of actual penetration of the sealant over the faces of the window frame and the brackets. Thus, the prior art systems have been deficient.

OBJECT AND STATEMENTS OF THE INVENTION The present invention has been devised to attempt to overcome the above problem.

Therefore, a first broad aspect of the present invention may be said to reside in a method of fitting a window frame in a window opening which is peripherally larger than the periphery of said window frame, said method e 20 having the steps of: 1. cutting a head channel, a sill channel and two jamb channels to required lengths to custom fit in said window opening, assembling said head channel, said sill channel and said two jamb channels to form a locating frame for said window frame in said window opening, said channels having a predetermined channel wall spacing width, in the direction of the thickness of the window frame, sufficient to accommodate receipt of edge portions of the window frame and weather sealing means for sealing said window frame relative to said locating H:\Gale\Keep\speci\CAP.Dowell.P21377.doc 1/08/97 4 frame, said channels each also having a channel wall height sufficient to overlap the weather side and inside faces of said window frame when said window frame is located within the channel walls of said locating frame and said locating frame is fastened to said window opening, 3. fastening said locating frame to said window opening and locating said window frame in said locating frame within the channel walls thereof, said method permitting said window frame and said locating frame to be sealed in said window opening by a. applying sealant between said locating frame and said window opening and b. applying sealant between said locating frame and said window frame, said method providing a window installation where eo "..movement between said window frame and said window opening 20 caused by thermal expansion or building movement is accommodated primarily by relative movement of said window frame within said locating frame.

In this way, appropriate sealant thickness can be applied between said locating frame and said window 25 opening, and further, appropriate sealing can be applied between said window frame and said locating frame. Such a *system enables relatively unskilled installation trades persons to assemble a window frame within a window opening and yet provide controlled fitting for appropriate sealant thickness which will accommodate for relative movements of the window frame, locating frame, and said building defining the window opening.

H:\Gale\Keep\speci\CAP.Dowe11.P21377.doc 1/08/97 5 It is particularly preferred that the sealant between said window frame and said locating frame be of the non adhesive type.

It is particularly preferred that the sealant between said window frame and said locating frame be a non adhesive sealant PVC or a similar plastics material to permit for movement of said window frame relative to said locating frame.

It is particularly preferred that the sealant between said locating frame and said window opening include two sealants one being a non adhesive sealant and the other being an adhesive sealant.

It is also particularly preferred that the channels for any of the head, sill or jambs be a two part channel having a first channel part defining the body of the head sill or jamb and one channel wall, and wherein the other part can be fitted to the body part to provide the other channel wall.

In this way the locating frame can be fitted in the 20 window opening, and then the window frame can be fitted in the locating frame, and finally the other part can be fitted to mechanically constrain the window frame within the locating frame.

It is particularly preferred that the two part channel 25 be the jamb channels.

It is also particularly preferred that the other part be snap lock fitable to the body part.

A window installation made according to the above method also forms part of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention can be more clearly ascertained examples of preferred embodiments will now be H:\Gale\Keep\speci\CAP.Dowell.P21377doc 1/08/97 6 described with reference to the accompanying drawings wherein: Figure 1 is a transverse vertical cross sectional view of an upper portion of a window installation of a prior art type.

Figure 2 is an exploded isometric view showing the rear view of a locating frame and a window opening in a building according to an example of a preferred embodiment of the invention.

Figure 3 is a transverse vertical cross sectional view of the example of the preferred embodiment.

Figure 4 is a transverse horizontal cross sectional view showing one jamb section of the example of the preferred embodiment of the invention.

Figure 5 is a view similar to that of Figure 3 conceptually showing the arrangement.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT Referring firstly to Figure 1, where a prior art 20 window installation is shown, it can be seen that there is provided a window frame 1 fitted in a window opening 3 in a building having wall surfaces 5. Usually a recessed p channel 7 is provided at the position of the window opening to provide for wind pressure equalisation as is known in 25 the building construction arts. The window frame 1 is delivered on site pre-manufactured. Trade persons then fit p brackets 9 around the window opening 3 to define a locating position of the window frame 1 relative to the window opening 3. The brackets 9 are held in place by suitable fastening means 11. Typically the brackets 9 are turned inwardly in the direction as shown. When the brackets 9 have been fitted around the window opening on the top, bottom and sides, the window frame 1 is moved into place H:\Gale\Keep\speci\CAP.Dowell.P21377.doc 1/08/97 7 and sealant 13 such as a bonding type silicone is smeared onto the abutting faces of the window frame 1 and the bracket 9. Further brackets 15 are then fitted on the inside of the window frame 1 by fastening means 11. These brackets 15 extend along the top, bottom and side walls of the opening 3. Further sealant 17 is similarly smeared on the abutting faces, and the window frame 1 is thereby held within the window opening 3.

A problem with such installation is that the thickness of the sealant 13 and 17 between the window frame 1 and the brackets 9 and 15 is not accurately controllable. In some instances, the sealant may have a thickness of only approximately imm. In some instances, the sealant may not extend completely over the abutting surfaces. Thus, when the window expands or contracts due to thermal changes there is relative movement between the window 1 the mounting brackets 9 and 15 and or the building wall surfaces 5. Further, there can be similar movement of this type caused by structural movement of the building wall 20 surfaces 5 such as occurring on settling of the building or due to thermal influences or the like. Thus, as known sealant such as silicone sealants tolerate only 25% maximum .o.o movement relative to thickness of the sealant then the above installation is not satisfactory. It has been found *25 that installations of the above type fail because the sealant breaks or ruptures shortly after installation.

It therefore can be seen that the above system offers .oo the following disadvantages.

1. The window frame is only sealed relative to the brackets 9 and 15 by a smear of sealant 13 and 17 2. The sealant application is not in accordance with manufactures recommendations where the H:\Gale\Keep\speoi\CAP.Dowell.F2i377.doc 1/08/97 8 sealant must have a width or thickness of application at least equal to 25% of any intended movement 3. The sealant is not repairable without disassembly of the window installation.

Typically this is not practical as rendering or the like is usually applied over the wall surfaces 5 and the brackets 9 and 15 to give a finished appearance to the building. This can typically be plaster or cement rendering.

4. The sealant is concealed and not visible.

The window installation is such that the window frame 1 is not able to move freely due to movement caused by thermal expansion or by movements in the building.

6. Typically the fastening means 11 are provided through openings of sufficient diameter to allow the shanks of fastening 20 means 11 to pass therethrough. Thus, the fastening brackets 9 and 15 themselves are not able to thermally expand lengthwise 0..

without applying unnecessary forces to the fastening means 11.

25 7. Building movement can be transferred directly to the window frame 1.

8. Any thermal movements or building movements *will frequently cause noise to be generated.

9. Wind pressure equalisation is difficult.

10. The window frame 1 is held to the brackets 9 and 15 by a means of rivets. Generally these rivets are visible and therefore unsightly.

H:\Gale\Keep\speci\CAP.Dowell.P21377.doc 1/08/97 9 11. There are three points of fixing which must each be attended to in a controlled manner.

The three points of fixing comprise:- 1. The fixing of the brackets 9 2. Fixing of the brackets 3. Fixing of the window frame 1 relative to the brackets 9 and 12. Usually a skilled installation team is required in order to achieve a mediocre result.

13. Accurate cutting to length of the brackets 9 and 15 is required in order to avoid uneven gaps at the ends where the head, sill and jamb sections intersect.

Referring now to the example of the preferred embodiment of the invention reference will firstly be made generally to Figures 2 through 4. In Figure 2, a building wall surface 5 is shown with a window opening 3 therein.

20 Typically the window opening can be in a concrete wall 5 or p in a brick wall 5 or any other wall 5. A window locating frame 19 is provided to fit within the opening 3 and be ne attached to the wall surfaces 21 therein. In Figure 2, the locating frame 19 appears as a single unitary frame 25 however, it should be appreciated that the locating frame is made up from a head section 23 a sill section 25 and two jamb sections 27. Desirably, these are each individually Sp fitted to the wall surfaces 5 within the opening 3 and a unitary frame is desirably not pre-made and then fitted within the window opening 3. Thus, the window opening 3 is measured and an appropriate length head 23, sill 25 and jambs 27 are cut from lengths of stock material for those sections. The head 23, sill 25 and jambs 27 are formed of H:\Gale\Keep\speci\CAP.Dowell. 21377 doc 1/08/97 10 channel material such as aluminium extrusion. The channels collectively form a channel in the locating frame 19 in which the window frame (not shown in Figure 2) can be received.

Each of the head section 23 and sill section 25 is provided with cut-out notches 29 which provide for neat fitting of the head section 23 and sill section 25 across the width of the opening 30. Thus, it can be appreciated that a front portion 31 of the locating frame 19 will overlap and surround the external wall surfaces 5 of the opening 3. The jamb sections 27 are cut to lengths which will fit within the remaining space between the head section 23 and sill section Figure 2 shows that the jamb sections 27 are received within the channel portions 33 of the head section 23 and the sill section 25. Thus, moisture which may be on the a. jamb section 27 within the channel portions 35 thereof will collect into the channel portion 33 of the sill Appropriate drainage may be provided within the sill 20 portion Figure 2 shows that each of the jamb sections 27 and head section 23 have a series of elongate slots 37 therein.

Similar slots are also provided in the sill section The slots 37 are provided to permit screws or other 25 fastening means to be passed therethrough and into the wall surfaces to hold the sections in place in the opening 3.

The elongate slots allow for relative movement caused by *oe .expansion of the sections 23, 27 or It should be appreciated that Figure 2 is partly schematic in nature and that the cross sections of the head section 23, sill section 25 and jamb section 27 are different, as will be referred to hereinafter.

H:\Gale\Keep\speci\CAP.D.Well1P21377 aoa 1/08/97 11 Referring now to Figure 3 there is shown the transverse cross sectional view of a typical installation of an example of a preferred embodiment of the invention.

Here, a window frame 1 has been shown diagrammatically in that the detailed section of the window frame 1 has not been shown. This figure clearly shows that the head section 23 and the sill section 25 are of channel configuration. This figure also clearly shows that the head section 23 has an outer flange part 39 which is arranged to overlap the outer or weather face of the wall surfaces 5 and that the sill section 25 has a similar flange part 41. Each of the flange parts 39 and 41 contains seal retaining arms 43 which, in turn, define a seal channel on the inside face of the flange parts 39 and 41 in which a PVC or like material bulb seal 45 can be received. The seal 45 is a non adhesive type seal. Thus, when the head section 23 and sill section 25 are in place and fastened through the elongate slots 37 by fastening means 47 to wall surfaces 5, then the bulb seal 45 will 20 compress against the outer weather side of the wall *'Ssurfaces 5 and provide a seal. If desired, a release tape may be provided over the wall surfaces 5 at that location to provide the sealing in accordance with sealant manufacturers preferred recommendations.

25 Referring now to Figure 4 there is shown a horizontal cross sectional view taking through the example shown in Figure 3 showing detail of the jamb sections 27. Here it o* can be seen that the jamb sections 27 are, in fact comprised of two parts. A first part 49 is provided from a generally shaped extrusion, and the second part 51 is provided from a generally shaped extrusion. The trunk 53 is provided with an offset 55 plus a flange part 57 which overlaps the outer face of the wall 5, and a further H:\Gale\Keep\speci\CAPDowell. P21377 .doc 1/08/97 12 flange 59 which provides one wall of the channel. The first part 49 can be fitted to the wall 5 by fastening means 47 passing through appropriate ones of the slots 37.

The flange 57 contains seal retaining arms 43 to provide a seal channel similar to that of the head 23 and sill 25 so that a further PVC or like bulb seal 45 can be received therein. When the first part 49 is fastened to the wall 5 as shown, the bulb seal 45 can provide sealing thereto. If desired, a release tape may be applied to the outer surface of the wall surface 5 at that location to assist in the sealing.

Figure 4 shows that the first part 49 is received within the upstanding channel walls of the sill 25. It is similarly received in the walls of the channel of the head section 23. The second part 51 of the jamb 27 is fitable to the first part 49 (which can be termed a body part) to define the other channel wall. In this example, the second part is snap lock fitable relative to the first part 49.

Here it can be seen that the first part 49 contains an arm 20 61 which defines a channel 63 into which a leg 65 of the a second part 51 can be received. The first part 49 has an inclined flange 67 which provides an undercut shoulder on the trunk 53 thereof. The leg 65 is provided with a complimentary inclined surface 69 which will permit the snap locking engagement of the second part 51 relative to the first part 49.

The second part 51 is only fitted to the first part 49 after the window frame 1 is located in the locating frame 19.

It should be noted that when the second part 51 is fitted to the first part 49 a channel wall 71 lies coplainer with a channel wall 73 of the sill 25. In this connection, the example shown in Figures 3 and 4 is H:\Gale\Keep\speci\CAP.Dowell.P21377.doc 1/08/97 13 slightly different to that shown in Figure 2 where the corresponding channel of the jambs are shown fitted within the channel walls of the sill It is noted that the locating frame 19, which is produced by the individual assembly of the head section 23, sill section 25 and jambs 27 to the wall surfaces appropriately locates the locating frame 19 relative to the opening 3. The window frame 1 can then be moved to fit within the locating frame 19. This is achieved by the relative dimensions of the channel sections formed by the head section 23 and sill section 25 permitting the window frame 1 to be moved upwardly fully into the channel section of the head section 23 and over the upper surface of the channel walls in the sill 25. The window frame 1 can then be lowered so it can rest on spacers (not shown) fitted within the channel of the sill 25 to position the window frame 1 to a predetermined height within the sill section 25. This will position the window frame 1 substantially in the position shown in Figure 3. The window frame 1 can 20 then be moved laterally from side to side between the jambs 27 to centrally locate it therebetween. The second part 51 can then be fitted to each of the jambs 27 to retain the window 1 captive within the locating frame 19.

If desired, spacers (not shown) may be provided 25 between the jambs 27 to centrally locate the window frame 1 between the jambs 27. All the aforementioned spacers may comprise packers which may be a plastics moulding or some other suitable convenient spacer or packer.

It can therefore be seen that the window frame 1 is fitted within an opening 3 which is peripherally larger than the periphery of the window frame 1. The channel width provides a predetermined wall spacing width in the channel in the direction of the thickness of the window to H:\(,ale\Keep\speci\CAP.Dfele11P21377doc 1/08/97 14 accommodate receipt of edge portions of the window frame and also to accommodate receipt of weather sealing means of a predetermined thickness to provide good sealant life expectancy. It is also seen that the locating frame 19 provides a channel formed by each of the individual channels of the head, sill and jambs which channel has a wall spacing width in the direction of the thickness of the window frame 1 sufficient to accommodate receipt of the window frame 1. It is also seen that each of the channels also has a channel wall height sufficient to overlap the weather side and the inside faces of the window frame 1 when the window frame 1 is located within the locating frame 19.

By inspecting Figures 3 and 4 it can be seen that each of the channels of the head 23, sill 25 and jambs 27 has channel walls where the free ends 75 are provided with in turned ribs 77. It should be noted, however, in the case of the jamb 27, the flange 59 is provided with seal retaining arms 43 which define a seal channel in which an 20 elongate cup shape seal 79 is received. This seal is made from a material such as PVC or the like and is a non adhesive sealant. Sealant means 81 in the form of a PVC or similar plastic material gaskets 81 can then be provided between the in turned ribs 77 of the channels to sealingly 25 hold the window frame 1 within the locating frame 19. Such sealant 81 is preferably a non adhesive type sealant.

The locating frame 19 can then, in turn, be sealed o*o Srelative to the wall surfaces 5 by an adhesive type sealant such as a silicone or like sealant 83 both on the weather side and the inside side of the locating frame 19.

By referring to Figure 5 which conceptually shows the installation it can be seen that the sealing of the window frame 1 relative to the wall surfaces 5 is effected by a H:\Gale\Keep\speci\cAP.Dowel .P21377 .doc 1/08/97 15 non adhesive sealant between the window frame 1 and the locating frame 19, as diagrammatically shown by sealant It is also effected by a dual seal formed by a non adhesive sealant 87 and an adhesive type sealant 89. In each case, the sealants 85, 87 and 89 can be controlled such that in the case of the adhesive type sealants 89, a considerable thickness or body can be provided which will allow for relative movement of the locating frame 19 relative to the wall surfaces 5 around the window opening 3. Typically, this is of sufficient thickness to accommodate expected movement and this be in accordance with sealant manufacturers specification of 25% movement in the thickness of the applied sealant. These sealants are readily visible without being unsightly.

In addition, it can be seen that the window frame 1 is then retained within the locating frame 19 so it can float therein. The non adhesive seals 85 are such that they are of pre-determined thickness and therefore allow for relative expansion or movement of the component parts 20 whilst still maintaining effective sealing. In other words a window installation is provided where movement between said window frame and said window opening caused by thermal ~expansion or building movement is accommodated primarily by relative movement of the window frame within the locating frame.

o .Whilst it has been shown that non adhesive sealant 81/85/87 may be chosen, the use of an adhesive material 5555.5 *sealant is not excluded. It is felt however, that superior results will be achieved if non adhesive sealant materials are used.

Returning now to Figure 3 it can be seen that the bottom of each of the channels defined by the head section 23 and sill section 25 are spaced from the wall surfaces H:\ale\Keep\speci\CAP.Dowell.P21377 doc 1/08/97 16 defining the opening 3 by legs 91. These legs 91 define a cavity between these sections and the wall surfaces 5 which can be used for pressure equalisation and appropriate air passageways may be provided in the sections for this purpose. In the case of the sill 25, drainage openings or mechanical flaps or the like may be provided therein to allow accumulated water to escape.

The following advantages can be realised from the example of the preferred embodiment 1i. The particular construction guarantees a minimum thickness of sealant dimension across the relevant seal areas.

2. Sealant dimensions are controlled and in accordance with manufactures recommendations for providing required degrees of movement 3. The sealant is easily inspectable, at least the adhesive sealant 83. In the event of any disconformity then the sealant 20 can be easily repaired.

4. The window frame 1 is able to float within the locating frame 19.

5. Because of the elongate slots provided in the head section 23 sill section 25 and 25 jamb sections 27 for permitting mounting or fastening to the wall surfaces 5, there can be movement of those sections independent of the window frame 1.

6. Minor building movement of the wall surfaces 5 is not transferred directly to the window frame 1.

H:\Gale\Keep\speci\CAP.Dowell.P21377.doc 1/08/97 17 7. Wind pressure loading can be balanced to minimise risk of water penetration into the building.

8. Noise from expansion on other building movement is unlikely to be generated by the window installation.

9. The window frame 1 may be premanufactured to size and the locating frame 9 custom fitted to the window opening 3.

Any laps at corner joints of the head section 23 sill section 25 and jamb section 27 can be easily sealed externally by a suitable sealant.

11. All fixing points are concealed and sealed.

12. A single line fixing point for the fastening means 47 can be provided by appropriate positioning of the slots 37 in 20 the respective head section 23 sill section 25 and jamb section 27. This, in turn, aids installation.

13. No special fixing skills are required and an unskilled trades person can provide 25 a quality installation.

14. Because the outer flange parts 39, 41 and 57 of the head section 23 sill section and jamb section 27 respectively overlap the weather face of the wall surfaces there is overlapping at all corners and accurate cutting to length of those sections is not critical.

H:\Gaie\Keep\speci\CAP.Dowell.P21377.do 1/08/97 18 Modification may be made to the invention as would be apparent to persons skilled in the window arts. For example, instead of having the jamb sections 27 in a two part form, one or both of the head section 23 or sill section 25 may be made of a two part form in a similar manner to that described for the jamb section 27. Further, if desired all of the head section 23 sill section 25 and jamb sections 27 may be of two part form.

These and other modifications may be made without departing from the ambit of the invention the nature of which is to be determined from the aforegoing description.

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Claims (10)

1. cutting a head channel, a sill channel and two jamb channels to required lengths to custom fit in said window opening,

2. assembling said head channel, said sill channel and said two jamb channels to form a locating frame for said window frame in said window opening, said channels having a predetermined channel wall spacing width, in the direction of the thickness of the window frame, sufficient to accommodate receipt of edge portions of the window frame and weather sealing means for sealing said window frame relative to said locating frame, said channels each also having a 20 channel wall height sufficient to overlap .o the weather side and inside faces of said window frame when said window frame is located within the channel walls of said locating frame and said locating frame is fastened to said window opening,

3. fastening said locating frame to said window opening and locating said window o* frame in said locating frame within the channel walls thereof, said window frame and said locating frame being sealed in said window opening by a H:\Gale\Keep\speci\CAP.Dowell.P21377.doc 1/08/97 20 a. sealant between said locating frame and building material defining window opening and b. weather sealant of pre-determined thickness between said locating frame and said window frame, said method providing a window installation where movement between said window frame and said window opening caused by thermal expansion or building movement is accommodated primarily by relative movement of said window frame within said locating frame. 2. A method as claimed in claim 1 wherein the sealant between said window frame and said locating frame be of the non adhesive type. 3. A method as claimed in claim 2 wherein the sealant between said window frame and said locating frame be a non adhesive sealant PVC or a similar plastics material to too* permit for movement of said window frame relative to said I..locating frame.

4. A method as claimed in any one of the preceding claims .:Q wherein the sealant between said locating frame and said window opening include two sealants one being a non adhesive sealant and the other being an adhesive sealant.

A method as claimed in any one of the preceding claims 25 wherein the channels for any of the head, sill or jambs be 0* a two part channel having a first channel part defining the body of the head sill or jamb and one channel wall, and wherein the other part is fitted to the body part to provide the other channel wall.

6. A method as claimed in claim 5 wherein the two part channel be the jamb channels.

7. A method as claimed in claim 6 wherein the other part is snap lock fitted to the body part. :\Gale\Keep\speci\CAP.DowelI .P21377.do 1/08/97 21

8. A window installation made by the method of any one of the preceding claims.

9. A kit of parts for performing the method of any one of the preceding claims 1 to 7 to provide a window installation said kit comprising: a. channel means for providing a head channel, a sill channel, and two jamb channels for a window opening by production therefrom of a locating frame as defined in any one of claims 1 to 7. b. a window frame for fitting within the locating frame as defined in any one of claims 1 to 7 whereby said window frame and said locating frame can then be sealed in said window opening by: i. applying sealant between said locating frame and building material defining said window opening and ii. applying sealant between said locating 20 frame and said window frame.

10. A method of fitting a window frame in a window opening substantially as herein described with reference to the accompanying drawings. 25 Dated this 1ST day of AUGUST 1997 DOWELL AUSTRALIA LIMITED By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent Attorneys of Australia H:\Gale\Keep\speci\CAP.Dowell.P21377.doc 1/08/97