WO1988001670A1

WO1988001670A1 - Window installation

Info

Publication number: WO1988001670A1
Application number: PCT/GB1987/000606
Authority: WO
Inventors: Alan Malcolm Harrison
Original assignee: Alan Malcolm Harrison
Priority date: 1986-09-06
Filing date: 1987-09-03
Publication date: 1988-03-10
Also published as: FI891023A0; GB2216940A; AU7859687A; DK252288D0; GB2216940B; FI891023A; JPH01503720A; DK252288A; GB8907743D0; EP0321484A1

Abstract

Method and apparatus for installing windows which avoids the need for man-handling windows up ladders or up scaffolding or through window openings from the inside, all of which as well as being potentially hazardous requires more than one person except for the smallest of windows, especially when pre-glazed. We provide a winch (29; 112) carried by a frame member (11; 100, 102) which is positioned internally of the window opening into which the window is to be fitted. The winch is coupled by a lifting line (31; 141) to a lifting harness (37; 130, 150) adapted to carry the window. The lifting line is passed through the window opening. Accordingly, operation of the winch allows the window to be lifted into the window opening from a position externally of the opening and below it. Attaching the lifting harness to the window glass by suckers (134, 136, 154, 156) allows glazed frames to be lifted into position. Advantageously the lifting harness provides adjustable abutments (158, 160) for the lifting line to assist in aligning the window with the opening. A pivotable guide arm (180) extending from the window opening and with which the lifting line cooperates further assists lifting and window fitting.

Description

Title: Window Installation

DESCRIPTION

The present invention relates to window installation and in particular to a method of fitting windows into a window opening, especially replacement windows, and to an apparatus for use in the method.

The fitting of replacement windows is a time consuming operation using the known installation • methods. One of the most time consuming parts of the operation is actually positioning the window frame into the window opening. This is especially difficult when windows above ground level are to be replaced as it is often essential to errect scaffolding at a convenient level if only as a resting point. The use of a hoist may be obligatory to carry the weight of large windows and is positioned externally of the building, conveniently fixed to the scaffolding. Errection of scaffolding and fixing up of a hoist is clearly time consuming. For smaller jobs ladders may be used and the window lifted up into position by two or more workmen without the use of a hoist. Clearly, this is potentially dangerous.

An alternative is to install the windows by passing them through the window opening from the inside, where the shape and size permits, but this too is a precarious operation requiring several workmen and almost invariably dictates that the glazing be omitted. With the other techniques, the glazing may be in place when the window frames are installed although this is rarely the case due to the difficulty in handling glazed units. There is clearly a need for a method of fitting windows which is simpler and quicker to perform preferably requiring less workmen and which avoids the need to errect scaffolding, and which as a consequence leads to more economic and speedier installation. A further aim is to be able to install window frames when fully glazed to further reduce .fitting time. The present invention aims to meet these objective by providing a new method of window installation, and apparatus for use in the method. According to the first aspect of the present invention then, there is provided a method of installing a window into a window opening in which lifting means for the window takes its abutment primarily internally of the window opening and the lifting harness for the window passes through the window opening so that the window is lifted into position from a starting position externally of the opening and below it.

We are predominently concerned with installing window frames, glazed or unglazed, but the method can be applied to installing glass into frames in a window opening.

In one embodiment of the method the window frame is guided along an inclined path by a guide member disposed externally of the window opening and conveniently terminating below, the bottom, of the opening. In another embodiment, the window frame is raised substantially vertically initially by running the harness over a guide arm projecting out from the window opening, and is then swung into the window opening by withdrawing the guide arm. The window frame is preferably carried on a craddle which has a connection point for the harness disposed above the bottom edge of the frame to ensure correct positioning of che window frame during the lifting and fitting movement.

By locating the lifting means internally of the window opening, the window frame is securely held

« during the positioning operation. The abutment . for the lifting means may be fixed but, as an alternative to provide latteral positioning of the window frame relative to the window opening, a side ways traversing arrangement is provided as an optional extra.

According to another aspect of the invention there is provided apparatus for use in fitting a window frame into a window opening, comprising a frame member carrying lifting means, conveniently in the form of a winch, which frame member is adapted for positioning in use primarily internally of a window opening to take abutment against a wall preferably above the uppermost edge of the window opening and conveniently having a second abutment which, in use, rests on a floor surface and preferably against the wall.

As an alternative to engaging the floor the second abutment could engage the bottom of the window opening.

More especially, the frame member is dimensioned to stradle the upper and lower boundaries of the window opening and is conveniently telescopic in nature so that a guide for the lifting means (which guide is preferably in the form of and idler roller) is carried adjacent the upper end of the frame work and can be positioned appropriately, height wise, for each window opening. The framework is conveniently a two stage rig with one member slidable Inside another and positioned adjustably with respect of one another by pin means received in mutually alignable holes of the two stages. Conveniently the winch for the wire lifting rope is attached to the lower stage. The winch may be hand or power operated. The frame member may be provided with a fixed foot at the bottom for locating it say in a corner adjacent wall and floor and with a fixed finger at the top for spacing the frame from any wall obstruction above the window opening, such as a curtain rail and/or pelmet. Where a window is being fitted to a new house the finger can be omitted as such obstructions would not normally be present at the time of window installation.

For use with the lifting means is a lifting cradle for the window, which cradle constitutes another aspect of the invention. One embodiment of cradle has a hook for receiving the end of the lifting harness and abutment means which receives the lower inside corner of the window frame to support the frame during lifting. Conveniently, the hook is carried on a member extending upwardly from the said abutment means and centrally thereof and preferably said member carries adjustably an upper abutment against which the window frame can rest. Said upper abutment is above the centre of gravity of the frame to ensure stability of the lifting cradle.

The lower abutment may conveniently take the form of an elongate member which is -shaped in cross-section. That at the top may be a simple elongate flat bar. A cap member or members, say of U-shape may be utilised to embrace together the top edge of the window frame and the upper abutment.

Another embodiment of cradle uses suckers attaching by suction to the glass say in a window frame to be fitted. Especially convenient is to use two pairs of suckers, say adjustably, _'mounted on a respective carrier. In use, one carrier- is positioned adjacent the bottom of the window frame with the suckers disposed in_^side ways relation, and the other above it and towards the upper edge of the window frame or as otherwise convenient. The use of suckers enables any size of window frame to be accommodated.

The carriers are adapted for engagement with cable or^' the like of lifting means and to this end both have guide means therefor. We find it convenient to use a loop of cable and to have the guide means of the bottom carrier in the form of a pulley rotatable relative to the carrier and around which the looped end of said cable passes. The guide means for the upper carrier conveniently comprises a pair of guide fingers, one for each of the two cable runs making up the aforesaid loop. These guide fingers are spaced apart so splaying out the cable towards the sides of the window relative to the substantially central position of the lower pulley. More especially these guides are pivotably mounted on the carrier with releasable catch means to allow swinging of the guides towards one another whilst at the same time moving the cable away from the window. This pivotable guide system allows adjustment of the angle of the window to aid final positioning by bringing it more towards parallel with the window opening.

The use of suckers is advantageous in that it does away with any obstruction around the bottom of the window frame and so allows glazed windows to be fitted straight into position and even fixed before release of the winch. The ability to install ready glazed units speeds up installation time and also reduces glass breakage which is high when the glass is installed separately.

According to another aspect of the invention, we find that a carrier having one or more suckers for affixing it to glass (on its own or fitting in a frame) can also be provided with one or more wheels, preferably two at opposite ends thereof, which can be deployed not only during lifting to assist in guiding the frame up a wall of a building and/or around any obstructions, without damage to the frame, but also as a means of manoeuvring the window frame, say on the ground.

The above described apparatus is quite suitable for installing first floor windows, where an inclined lift up a convenient guide, (even a ladder will suffice) is possible. For higher elevations it may be preferable to lift the window frame vertically and then swing it into the window opening. For this purpose a pivαtable guide bar is employed which carries roller means at its free end over which the lifting wire rope/cable(s) passes. Conveniently, the guide- arm is carried on a support plate which can rest on the lower edge of the window opening. The guide bar can be arranged to pivot automatically and an adjustable stop provided for final positioning or a strut provided to secure the support plate to the frame member, which strut can serve to adjust the angle of the guide bar, preferably by screw threaded adjusting means.

According to this further aspect of the invention then we find that the window installation can be assisted if we have a guide bar which is positioned to extend from the window opening adjacent the lower boundary thereof on which it conveniently takes its abutment, preferable also coupled to the frame member inside the room. More especially we find it advantageous if the guide arm carries pullies to receive the wires of the lifting cable conveniently spaced apart relation corresponding to the spacing of the wires in the upper carrier of the lifting craddle, and more especially to have the arm freely pivotable and positioned for engagement by the window frame being lifted in such a way as to pivot towards the window opening on contact by the window frame/cradl'e thereof. Whilst we say freely pivotable, we do infact prefer the hinge of afford a small resistance to pivoting so that the arm does not pivot merely under the frictional force of the wire passing over the pullies, but requires contact by the frame. Also we prefer to have the arm pivotable for movement in the opposite direction say on lowering of a window. Movement in this respect is rendered possible by a lip or latch plate on the guide bar co-operable with the window frame or carrier.

More especially the pivotable guide arm carries an abutment to limit automatic pivoting of the guide arm but which abutment is manually adjustable thereafter for final positioning. Said guide arm connection with the frame member is such as to permit swinging of the guide arm in a transverse plane so that the guide arm can be withdrawn out of the way into the room. Additional means may be provided to restrict swaying movement of the window possibly caused by the wind. Such means may comprise guide ropes attached to the ends of the shaft of the idler pulley on the end of the guide arm and to the lifting cradle. To further assist transverse alignment of the window frame, the aforementioned ^" fixed foot and finger for the frame member can be replaced by a traverse mechanism, whereby the frame member can be adjusted for position side-ways. Rollers and/or wheels may be employed to permit movement and these may be free wheeling or more preferably, positively driven.

One convenient embodiment comprises a belt entrained around a pair of spaced apart pullies. The spacing provides the required stability for the framework. Such a construction can be employed at both the foot and head of the framework. Conveniently, both units are driven by means of a bevel gear arrangement with a telescopic driveshaft between the upper and lower drive gears. Conveniently, said drive shaft is constructed of hollow square section material for ease of grip and to allow vertical adjustment to correspond to the height adjustment of the frame member and yet allow driving rotation thereof by hand rotation.

Zero pressure against the wall can never be achieved with loads outside the pivot pressure point.

The present invention will now be described further, by way of example only, with reference to the accompanying drawings; in which:-

Figure 1 is a side view .showing the method and .apparatus of installing a window.frame according to the_. present invention;

Figure 2 is a side view in the position of use of additional items of apparatus for lifting with vertical and swing action;

Figure 3 is a side view of a traversable frame member;

Figure 4 is a schematic front view of the traversing arrangement;

Figure 5 is a more detailed view of a traversing mechanism and drive therefore;

Figures 6 and 7 are a front and side elevation respectively of the basic frame member used in the apparatus; Figures 8 and 9 are respectively a rear view of a frame supporting cradle and a side view of the cradle with frame in position;

Figure 10 is a front elevation of the main frame of a lifting rig according to another embodiment of the invention;

Figures 11 and 12 are elevations of respective lower and upper carrier parts of a lifting craddle; and

Figures 13 and 14 are side elevation and plan of an extension arm for use with the frame of Figure 10.

Referring more particularly to the drawings,

Figure 1 shows a window opening 1 in a cavity wall 3 of a building, with a lintel 5 over the window opening.

Flooring and joists are shown at 7 defining a floor in the building. Positioned on the ouside of the building and leaning against the wall is a ladder 9 which serves as a guide during window fitting, as described hereinafter. The lifting means comprises a frame member 11, In the form of a two stage extendable rig as illustrated with one part slidable in the other. Pin means 25 is provided to engage in mutually alignable holes 27 of the two parts for setting the rig at the desired length. Rectangular hollow section steel is particularly suitable for the twb parts. A ^'foot is shown at 13 which fits into the bottom end of the frame member and secured in position by screw threaded means 15 as illustrated, or alternatively, pin means. A resilient stop may be provided at 17 to abut against the wall/skirting board and the bottom edge of the foot preferably incorporates a high friction material to ensure good location where the foot contacts the floor. An optional finger 19 is shown fitted into the tap end of the frame member and secured in position using a screw threaded clamp arrangement 21 as illustrated. A resilient high friction grip is provided at 23.to contact the wall surface. The finger throws out the top of the .frame member to clear the' pelmet and curtain rail illustrated at 25.

Alternative mechanical fixing • means can be provided for the foot and finger, or they can be welded in place when provided as permanent fixtures. The lower frame part 11a carries a winch assembly 29, hand or power operated, with a wire rope 31. The adjustable frame part lib carries a guide for the wire rope, which guide is in the form of an idler roller 33.

The window frame to be fitted into position is illustrated at 35 located in a lifting cradle 37

(illustrated further in Figures 8 and 9). The cradle has a hook 39 onto which the end of the wire rope 31 is attached. The cradle 37 comprises a transverse elongate member 41 of L-shaped cross-section and welded intermediate its length to one end of a support tube 43. The member 41 embraces the inner lower corner of the window frame 35. The support tube 43 is hollow to receive adjustably a strut 45 of an upper transverse window frame support 47 welded to the strut. Suitable mechanical fixing means 49 is provided for locating the members 41 and 47 at the desired distance relative to one another. A threaded nut welded to the tube 43 and receiving a threaded fixing bolt engaging the tube 45 is one possibility. The member 47 carries one or more soft pads 51 along its length to contact the window frame without damage. To aid security of the window frame on the cradle a security cap or caps 53 of inverted U-shape Is/are provided to embrace the member 47 and the top member of the window frame. This simply pushes into position for ease of fitting and removal.

As will be seen from Figure 1, the window frame is guided up the ladder 9 with the member 41 of the craddle running on the ladder. Adjustable guides may be provided fon the member 41 to embrace the sides of the ladder for positioning purposes. The position of the hook 39 from the bottom of the window frame, and the height of the guide idler 33 are arranged so that the top of the window frame is drawn into the window opening. The lifting .apparatus, being wholely accommodated internally, does not hinder fitting of the window frame into the window opening. If necessary one man can fit a window using the described apparatus since the window frame is held against falling by the abutment of the lifting means internally. The lifting apparatus is of compact construction so that it can be easily brought indoors and errected in the required position. The approximate angle of the load stress is shown by the arrow S and the pivot point for the load pressure is shown at P.

Figure 2 illustrates additional apparatus for use in fitting more elevated windows, or in locations where a guide (ladder) 9 cannot be easily employed. A support plate 61 is shown which rests on the lower edge of the window opening and is additionally secured to the framework 11 (not illustrated) by a clamp 63 carried on a pivotable bar 65. Upstanding from the support plate 61 are two parallel spaced apart struts 67 disposed side by side. A guide arm 69 is pivotably mounted on the support plate 61 and carries at its outer free end a pulley 71 for receiving the wire rope 31 of the winch lifting means. A cill plate 73 restricts outward pivtoing of the guide arm 69 and inward pivoting is controlled by screw threaded adjustment means. For this purpose a screw threaded strut 75 rotacable by a hand wheel 77 is received in a threaded swivel nut 79 journalled in the guide arm. By using the pivotable guide arm 69, a window frame can be lifted vertically up to level with the window opening and then by pivoting the arm, drawn into the window opening and the guide arm apparatus removed when the load is supported by the wire passing over the idler 33. The cradle 37 may be conveniently provided with a. catch 81 for locating the wire for vertical lifting.

Referring now to Figures 3 and 4, the basic frame of the lifting means is shown at 11 comprising a similar elongate extensible strut carrying winch mounting and wire rope guide roller. The opposite ends of the strut, i.e. foot and head are hollow in the illustrated embodiment to receive top and bottom mounting plates 101, 103 for traversing means 105, 106. A roller 107 is mounted at the foot for engaging the walls/skirting board, conveniently having a soft high friction peripheral coating.

- A front view of the foot traversing means is shown in Figure 4. It comprises two pulleys 109 journalled _ on a mounting plate around which is entrained a flexible belt 111 conveniently a V-belt. Alternatively, toothed wheels and belt may be employed. Idler rollers 113 are provided tc hold the belt in contact with the floor on which the rig is supported for movement transversly.

One of the pulleys 109 is provided with a bevel gear 115 mating with a gear 117 which is rotatably driven by a drive shaft 119. The drive shaft 119 is of two part construction and conveniently of square section, allowing extension thereof the•compliment the length of the main frame member 11. The upper part of the drive shaft 119b carries a bevel gear at its upper^" end which mates with a bevel gear on a pulley 121 of a similarly constructed traversing mechanism 105. The upper mechansi is dispaced substantially in a horizontal plane to co-operated with the wall and define the upper pivot/pressure point for the frame member. A similar rubber belt 111 is employed entrained around rollers 109'. By rotating the drive shaft, the pulleys 109,

109' are rotated and the lifting rig is moved laterally relative to the window opening for .correct alignment of the window frame being lifted.

An alternative construction of traverse mechanism is illustrated with reference to Figure 5, showing the parts exploded and for fitting to a modified construction of frame member illustrated in Figures 6 and 7.

The frame member comprises hollow parts 11a, lib slidable one within the other. A winch mounting plate is shown welded to part 11a at 83. Holes 27 are provided for locating the part 116 adjustably relative to part 11a. The lower part 11a has a plate 85 welded thereto for mounting of the traversing mechanism and can also serve as a support foot, when the traversing mechanism is- -not mounted in position. A soft high friction layer 87 is provided along the bottom edge of the plate.

A mounting plate 89 for the upper traversing mechanism is secured to the part 116 by two spaced apart plates 91. Bores therein 93 receive a pin on which the wire rope idler pulley 33 is journelled for rotation in a position between the plates.

The pulleys in the form of cogged pulleys 119 are mounted on the plates 85, 89 by means of pins and washers as shown at 127 and carry internal on bevel drive gear 123 secured to the drive shaft 119' by split pins 129₄, whith the lower gear accommodated within a cover 125. Also shown are lugs 131 secured to the driveshaft to assist turning thereof, and low friction material 133 as thrust journals for the pulleys 109. Geared belts are shown at 137 entrained around pairs of pulleys 119. The pulleys 119 and bevel gears 23 may be made as a die casting or a plastic moulding. Each 5 pulley is conveniently provided with gear teeth, but only the ones driven by the bevel gear of the drive shaft is used in operation.

Referring now to Figures 10 to 14 there is illustrated a further embodiment of the invention. For 10. convenience we term this our twin wire design. Referring firstly to Figure 10, the rig comprises an elongate frame member, conveniently of hollow round section stainless steel (to give required strength with compact construction), having two parts 100, 102 with 5 one slidable in the other for height adjustment and facilitating collapse for transportation. One part 102 has holes for a pin 104 to set the frame at any desired length. A cross bar 106 is located at the end of the part 102 and carries, to opposite sides of the frame 0 102, two rotatable pullies 108, 110 and outwardly of these rubber abutments 120 serving as wall contact points for the frame.

A winch 112 for wire cable is fixed adjacent the upper end of the lower frame part 100 and is hand 5 operated by handle 111 as indicated and conveniently incorporating a one-way ratchet to prevent accidental unwinding under load. The winch may be electrically operated as an alternative. A looped wire/cable 114 has the two ends fitted to the winch spool 116. A weight spreading foot 122 is provided at the bottom of the lower frame part 100 conveniently connected by way of a pin joint as shown at 124. A first clamp is shown at 126 and the purpose of this will be described further herein below. Referring now to Figures 11 and 12 there is illustrated means to facilitate lifting of a glazed window frame comprising two carriers. The carrier 130 illustrated in Figure 11 comprises an elongate bar 132 on which are mounted two suckers 134, 136 adjustable axially thereon in slots 135 using screw or cam action clamps. The suckers are of conventional design having manual pump means for generating desired suction when suckers are placed on glass of a frame to be lifted. The carrier has mounted rotatably thereon a pulley 138 conveniently in housing 140. The looped end of cable 114 passes around said pulley. Also mounted on the carrier at opposite ends thereof for deployment are wheels 142, 144, being pivotable from the illustrated position to one at 90 degrees thereto. The purpose will be'described hereinafter. Figure 12 shows an upper carrier 150 having a similar elongate frame member 152 into a corresponding pair of suckers 154, 156 mounted axially movable thereon and likewise having screw or cam type clamp means. The frame also has two guide arms 158, 160 pivotably mounted thereto at 162, 164. The guide arms have a bend therein conveniently S-shaped to serve as location/retention means for respective runs of the looped wire/cable 114, the runs being hooked round the guide arms as illustrated at 170, 172.

. Releasable cat-.. ; means are provided for retaining the guide arms in a- first position, as illustrated in

Figure 12, and conveniently taking the form of pins

174, 176 slidable in the arms and engagable in reception means in the carrier.

The lifting craddle comprising of the aforedescribed suckers is advantageous in being able to fit to any design of window frame irrespective of frame parts. Furthermore, the twin wire/loop arrangement gives a more balanced and controllable lifting action. Whilst the pivotable guide arms allow the window inclination relative to the window opening to be adjusted into a more parallel attitude immediately prior to winching into the window opening. To further assist in lifting and fitting of the window we find a further guide arm to be advantageous such as that Illustrated in Figures 13 and 14. The guide comprises an arm member 180 hinged at 182 to an abutment member 184 which locates on the bottom sill of the window opening (i.e. window ledge). Conveniently this of two part construction with inner 186 and outer 188 members slidable one within the other for adjustment of axial length and having a clamp lock 190 at the end for fixing to the frame member 100 - see also Figure 10. The window abutment member extends from ^"the outer member and has a flange part which engages around the outer edge of the window opening.

The arm member 180 carries a transverse arm 192 whose ends have pullies 194, 196 for receiving the respective parts of the lifting loop 114. Also illustrated is an actuating abutment 198 having first and second abutments 198a and 198b.

When in the position illustrated, a window frame being lifted or more usually the upper carrier 150 contacts the abutment causing the arm 180 to pivot upwards as the window is raised further. This is advantageous in bringing the window frame towards the window opening. A lip 199 of abutment 198b engages with a lip of the carrier 150 before the arm gets to a 45 degrees angle to prevent the arm and hence the window from swinging uncontrollably towards the window opening. An adjustable stop 200 carried by the movable arm 180 determines the point when automatic pivoting stops and manual control is resumed to achieve final positioning. The second abutment 198b also comes into play in the event of the window having to be lowered after the hinged arm 180 has gone over centre as happens when it approaches its vertical position (infact past the 45 degrees point). In this situation the bottom carrier engages the lip 198b causing the arm to be entrained by the carrier and therefore give outward pivoting to set the frame off from the building as desired. As the arm pivots outwards it automatically disengages from the carrier. In operation of the embodiment of Figures 10 to

14 then, the frame member 100 is first positioned in the room, inside of the window opening with its foot 122 abutting the floor and it abutments 120 contacting the wall with any height adjustment made as necessary - having usually been carried on site in its collapsed position. The guide arm 180 is then fitted on to the arm, if not already in place and swung out, its length aαjusted to position the abutment 184 around the window edge. The lifting cable can then be palyed out and over the pullies 108, 110, 194, 196. Down below, the carriers 130, 150 are positioned on the glass in the frame to be lifted. Conveniently the frame is positioned with its centre line approximately in line with the centre of the two carriers. The lower carrier is positioned spaced from the bottom of the window frame such that the wheels thereof are engageable with the ground to allow movement of the frame on the ground using said whels if desired. The spacing of the suckers may be adjusted to allow fitting where .larrow frames are involved. The lifting wire is entrained around the guides therefor. Lifting may now commence, by winding in the cable using the winch. Lifting is initially vertical up to the point of contact of the upper carrier 130 with the abutment 198a when the guide arm starts to pivot inwards on continued elevation. This causes the frame to move towards the window opening, but still inclined relative thereto. The guide arms 158, 160 may then be unlatched and pivoted outwards causing the window frame to pivot outwards at the top because the length of the cable is effectively increased bringing it approximately parallel to the window opening. The bottom of the frame being held by the guide arm may then be moved towards the frame by adjustment of the abutment too before the guide bar is finally swung inwards. Further actuation of the winch pulls the frame into position, where it can be fixed before release of the suckers.

Claims

1. Window fitting 'apparatus comprising a frame member carrying lifting means, an upper end of the frame member has a wall engaging abutment and the other end carries a support foot whereby, in use, the frame member is adapted for positioning internally of a window opening to take its abutment at least partially against a wall bounding the window opening, and rotatable_ guide means carried adjacent the upper end of the frame member, and wherein the lifting means comprises a winch carried by the frame member and coupled by a lifting line to a lifting harness adapted to carry the window, the lifting line passing over said rotatable guide means.

2. Window fitting apparatus as claimed in claim 1 in which the frame member comprises two elongate members which are telescopic so that, in use, the wall engaging abutment and the support foot are positioned to staddle the upper and lower boundaries of the window opening with the support foot abuting a floor surface.

3. Window fitting apparatus as claimed in claim 1 or 2 in which the lifting harness comprises a cradle having abutment means to receive the lower inside corner of a window and an arm extending upwardly from the abutment and carrying a hook to receive the lifting line.

4. Window fitting apparatus as claimed in claim 1 or 2 in which the lifting harness comprises one or more suckers attaching by suction to the window glass and wherein the harness carries spaced lifting line engaging means which, in use, are positioned one above the other.

5. Window fitting apparatus as claimed in claim 4 in which ^• the lower of the lifting line engaging means comprises a rotatable guide roller around which the lifting line is looped.

6. Window fitting apparatus as claimed in claim 4 or 5 in which the upper of the lifting line engaging means comprises two guide fingers one for each run of looped lifting line and providing adjutable abutment positions for the line.

7. Window fitting apparatus as claimed in any one of claims 1 to 6 further comprising a guide arm arranged to be extensible and retractable from the window opening adjacent the lower boundary thereof and provided with guide rollers with which the lifting line cooperates.

8. Window fitting apparatus as claimed in claim 7 in which the guide arm -is mounted for pivotal movement when contacted by the lifting harness or window on movement thereof.

9. A method of installing windows into an opening comprising positioning lifting means for the window with its abutment internally of the window opening, passing a lifting harness of the lifting means through the window opening which harness is adapted for attaching to the window then externally of the opening and lifting the window into the opening from a position externally of the opening and below it by operation of the lifting means.

10. A method as claimed in claim 9 further comprising initially lifting the window generally vertically by passing the harness over a guide arm extending from the opening and then swinging the window at least partially into the opening by withdrawing the guide arm.