GB2034382A - Window frames - Google Patents

Abstract

Alternatively the frame is wholly of g.r.c. A window frame 10 moulded in (g.r.c.), has an auxiliary frame 16 pivoted to form a movable light, a sill member 20 and a head member 26, also moulded in g.r.c. The g.r.c. side members of the frame 10 provide sufficient support to enable the head member 26 to bear the weight of building elements 30 above the aperture in which the frame is fitted without the need for a lintel extending into and interfering with the building elements at the side of the aperture, thus making construction easier. Window frame members comprise an outer skin 56 of plastics filled with a settable composition. For example, a frame is moulded from glass fibre reinforced cement (g.r.c.) in a polyvinyl chloride skin, which both acts as a mould and gives the frame a good external appearance. <IMAGE>

Description

SPECIFICATION Frames for apertures in buildings and methods of making them This invention relates to the construction of apertures such as doors and windows in buildings.

Frames for apertures in buildings, e.g. window frames, are traditionally made from timber, but this material requires regular painting and maintenance and eventually replacement.

Frames made from steel or aluminium are also well known, but are not inexpensive and there are problems with condensation owing to the heat conducting properties of these metals.

More recently, polyvinylchloride (PVC) frames have been introduced. These have a good appearance and do not need painting or maintenance, but they are expensive, especially since the PVC must be very thick to give the frame the necessary structural strength and rigidity.

According to one aspect of the present invention, there is provided a method of making a frame for an aperture in a building, comprising arranging a hollow skin of plastics material to define the frame, filling the skin with a settable reinforcing composition, and allowing the settable composition to set, whereby the plastics skin acts as a mould for the settable composition and forms an outer surface for the frame. The plastics skin may be much thinner than in known PVC frames, so reducing expense.

Preferably the settable composition contains a fibrous reinforcing material, and the composition may be a cementitious material such as glass fibre reinforced cement (g.r.c.). Preferably the hollow skin is of tubular crosssection so as substantially to enclose the settable composition as it sets. With g.r.c., this ensures that the conditions in which it cures are optimum in order to develop the best strength characteristics and to lessen the likelihood or degree of a reduction in strength as the material ages.

According to a second aspect of the invention there is provided a frame for an aperture in a building, having frame-forming members which comprise an outer skin of plastics material filled with a settable reinforcing composition.

According to a third aspect of the invention there is provided a construction of an aperture in a building, including a frame for the aperture, the frame having one or more vertical members extending substantially from the top to the bottom of the aperture, the vertical member or members being made from a load supporting material. By "load supporting material" we mean that the vertical member or members should be capable of supporting the load of the building elements above the aperture, without the need for a lintel to spread the load to the building elements at the side of the aperture.

Preferably there are at least two said vertical support members, one at each side of the aperture. There may also be such vertical support members at intermediate positions between the sides. Two or more modular frames may be provided in the aperture, each module having two vertical support members at its sides, the vertical support members of adjacent frames being joined together in abutment to form composite intermediate vertical support members. The rest of the frame may be made from the same material as the vertical support members. Most suitably, the load supporting material is glass fibre reinforced cement (g.r.c.), and the frames may be moulded in g.r.c.

Preferably the frame has a head member at the top thereof spanning the vertical support members to support building elements above the aperture. The head member may have a flange or flanges extending forwardly and/or rearwardly. This is paricularly useful where the building has a conventional cavity wall construction, since the frame can then lie generally in the plane of the cavity with the flanges on the head member projecting forwardly and rearwardly to support the inner and outer skins of the wall respectively.

Two window constructions embodying the invention will now be described by way of example, with reference to the accompanying drawings, wherein: Figure 1 is a front view of one window construction, Figure 2 and 3 are vertical cross-sections along the lines A-A and B-B respectively in Fig. 1, Figure 4 shows an alternative form of head member, Figure 5 is a horizontal section along this line C-C in Fig. 1, Figure 6 is a front view of the second window construction, Figure 7, 8 and 9 are cross-sections along the lines D-D, E-E and F-F respectively in Fig. 6, Figure lOis a cross-section showing a head member for the second window construction, Figure it is a cross-section showing a sill member for the second window construction, Figures 12 and 13 are cross-sections through plastics skins for two further window frames, and Figure 14 shows a jig for the manufacture of the frames of Figs. 1 2 and 1 3.

Referring to the drawings, and firstly to Figs. 1 to 5, the window constructions comprise several modular frame units which are each moulded from g.r.c. In Fig. 1, there are seen two such modular units side-by-side, but windows could be made up with just one modular unit, or with three or more units.

Each module comprises a rectangular frame 10. Inside the rectangular frames 10 (which can be sub-divided by member 12) there are provided lights, which may be a fixed light 14, or may have auxiliary frames 16 which are hinged to the frame 10 by hinges 18.

The foot of the frame 10 rests on a sill member 20, being bonded in a channel 22 thereof, for example with an epoxy resin adhesive. The silt member 20 is supported on building elements 24 forming the inner and outer skins of a cavity wall. At the top of each frame 10, there is a head member 26, which has a longitudinal reinforcing rib 28 which fits in the cavity between building elements 30 of the inner and outer skins of the cavity wall above the aperture. The head member 26 also has two smaller depending parallel ribs 32 which form a channel in which the frame 10 is bonded in the same manner as in the channel 22 of the sill member 20. The head member 26 has flanges 34 which project forwardly and rearwardly from the frame 10, and the building elements 30 are supported on these flanges 34.The head member 26 at its ends rests on the vertical members of the frame 10, and since the vertical members are formed of g.r.c. which is an effective load bearing material, the weight of the building elements 30 above the aperture can be borne without the need for any lintel extending into engagement with the building elements 36 at the side of the aperture. It is therefore possible to make a much neater aperture, there being no need to interrupt the line of the building elements 36 at the sides of the aperture. In building the wall containing the aperture, the sills 20, frames 10 and head members 26 are simply built in as the work proceeds.

Where a window is being made up from two or more modular units, it is desirable that their frames 10 shoud be secured together.

This can be achieved as seen in Fig. 5 by simply moulding bolt holes 38 into the construction of the vertical members of the frames 10. These bolt holes are countersunk and spaced at regular intervals along the length of the vertical members. It is easy to insert bolts to join the adjacent frame members 10 together, or alternatively the adjacent members could be joined by screws. Mastic can be applied between the frames 10 to prevent the ingress of moisture.

Fig. 4 shows an alternative heavy duty head member 40, which can replace the head member 26 where there is a particularly heavy load above the aperture to be supported. Usually this will happen where the inner skin of the cavity wall has to support a floor which will take high loadings. The head member 40, like the head member 26, has a forwardly projecting flange 34 to support the outer skin (which will not be subjected to the high loadings) and also depending ribs 32 forming a channel to accommodate the frame 10. Instead of a rearwardly projecting flange 34, however, it has a box section 42 on which is supported the inner skin 44. Such a box section 42 has much greater strength than a mere flange 34.It could also, if desired, be reinforced in the same manner as the lintels dscribed in our co-pending Application No. 26261/78, though of course it is not a lintel as it does not extend over the building elements 36 at the side of the aperture.

Suitably the modular units are about two feet wide, and can be made in a number of different heights. It will be notices that, where the frames 10 of adjacent modules abut, there is effectively a composite, double thickness vertical support member. This is useful because it occurs at intermediate points between the sides of the aperture, where a load bearing member is most needed since those building elements 30 above but towards the sides of the aperture will usually interlock with the building elements 36 at the sides, and thus reduce the support which is necessary actually at the sides of the aperture.

One problem with any window or doorframe is to provide an acceptable finish. A particularly preferred approach to this problem is exhibited by the window construction shown in Figs. 6 to 11. Referring to those drawings, the window has a generally similar construction to that seen in Figs. 1 to 5.

However, in place of the frames 10 and auxiliary frame 16, there are provided fixed frames 52, 53, and an auxiliary frame 54 hinged to one of the fixed frames, 53, to provide an openable window. Each frame 52, 53, 54 is moulded from g.r.c., but unlike the frames seen in Figs. 1 to 5 they have an outer covering 56 of polyvinyl chloride (p.v.c.). This outer covering serves a two-fold purpose: it provides an attractive and maintenance free finish to the frames, and it serves to provide a mould for the g.r.c. when the frame is being formed.

This latter feature can be seen especially from Figs. 7 to 9. In Fig. 8, it can be seen that the p.v.c. covering 56 of the frame member 52 is generally channel-shaped, with a restricted mouth 58 provided by inturned flanges 60. The inturned flanges 60 are formed with V-shaped grooves 62. At the inner edges of the flanges 60, there are depending lips 64. The covering 56 is extruded in lengths, the ends of which are mitred at 45" as seen at 66 (Fig. 6). Four such mitred lengths are then welded together to form the desired rectangular frame 52.

Subsequently, the channel sections are filled with g.r.c., in a jig which stops up the open mouths 58. This jig also provides for a recess 68 in the g.r.c. in the mouth 58, in order to save g.r.c. and reduce the finished weight. In the moulding process, the downturned lips 64 become set into the g.r.c., in order to key the covering 56 to the g.r.c. To improve this keying, the inner surface of the covering 56 may be extruded with ribs 70, for example at internal corners of the channel section or elsewhere.

The channel section covering 56 (and there fore the finished frame 52) is provided with a shaped recess 72 around the inner edge of its outer face. This recess 72 is shaped to receive a pane of glass 74, which is pressed against a gasket 76 by a conventional press fitted plastics glazing strip. Glazing systems of this type are well known, for example under the Trade Mark REDDIPLEX.

Referring to Fig. 9, the frame 53 is generally constructed in the same manner as the frame 52. However, it has a recess 78 around the inner edge of its outer surface, providing a shoulder 80. The auxiliary, hinged frame 54 is received in this recess 78, and abuts against the shoulder 80 when the window is closed. The auxiliary frame 54 also has a p.v.c. covering 82 similar to the covering 56.

This covering 82 is also of channel section, but unlike the covering 56 the open mouth of the channel is arranged on the rearward surface of the frame 54 when in position, and as can be seen in Fig. 9, it is covered by a snapon p.v.c. cover plate 84 in use. In manufacturing the frame 54, extruded lengths of the covering 82 are mitred at 45 as seen at 86 (Fig. 6). The lengths are then welded into a rectangular form, laid horizontally with the open mouth of the channel sections upwards, and filled with g.r.c. The cover plate 84 is fitted after the g.r.c. has set. The inner edge of the front face of the frame 54 has a recess 72' in which fits a pane of glass 74 in exactly the same manner as in Fig. 8.

The cover plate 84 of the frame 54 is fitted with a conventional weatherproof sealing strip 86, which when the window is closed abuts closely against the shoulder 80. A further such weather strip 88 is provided on an outwardly extending flange 90 of the frame 54, and abuts against the front face of the frame 53. Suitably, the weather strips 86, 88 are of the pile type such as that available under the Trade Mark REDDIPILE.

As seen in Fig. 7, the cavity between the inner and outer skins 48, 50 of the cavity wall is bridged by a vertically arranged moulded g.r.c. cavity closure piece 92 which has two ribs 94 which fit inside the cavity.

This cavity closure piece is secured (e.g. by bolting) to the vertical side member of the frame 52 or 53, and thus forms part of the vertical support member. It has a longitudinal groove 96 corresponding to one of the grooves 62, and in position the grooves 96, 62 produce a vertical channel within the thickness of the frame construction, running near the front face thereof. A p.v.c. sealing strip 99 having a compressible bead 100 fits in this channel, preventing the ingress of draughts, moisture, etc. The p.v.c. sealing strip also has an integral external flange 98 covering the crack between the closure piece 92 and the frame 52 or 53. This flange 98 is shown partially cut-away in Fig. 6. A similar p.v.c. sealing strip 99 is used where the frames 52 and 53 meet, in which case the bead 100 is compressed within a vertical channel formed from two co-operating grooves 62.

As seen in Figs. 10 and 11, a slightly different form of sealing strip 102, also made from p.v.c., is used at the top and bottom of the frames 52, 53, between the frames and a head member 114 and sill member 106. In Fig. 11, the sealing strip 102 has a longitudinal bead 100 which is compressed in a channel formed between a groove 62 and a groove 104 in the sill member 106. Projecting from the bead 100, there is a p.v.c.

flange 108, which is slightly downturned at 110 in order to conform to the upper surface of the sill 106 outside the window. A similar p.v.c. sealing strip 102 is used between the top of the frame 52, 53 and the head member 114 (in Fig. 10), the flange 108 projecting so as to lie above the auxiliary hinged frame 54 and not interfere with its opening and closing. On the internal side of the sill in Fig. 11, there is also a groove 104 cooperating with grooves 62 in the frame members 52, 53, in which is compressed a p.v.c.

sealing strip 1 03. In like manner this has a projecting flange 108, but in this case the flange is straight without any kink. This is so that the flange 108 lies across the junction between the sill member 106 and an internal window ledge 112.

The head member seen in Fig. 10 is an improved version of that seen in Figs. 2 and 3. In place of the symmetrical cross-section rib 28, there is an asymmetrical rib 46. When this rib 46 is positioned in the cavity between the inner skin 48 and the outer skin 50, it lies towards the inner skin and away from the outer skin. The result of this is that for a given weight of the rib 46, reinforcement is provided for the rear flange 34a supporting the inner skin 48 than is provided for the forward flange 34b supporting the outer skin 50. This is advantageous in buildings where the inner skin can be expected to take a higher loading as a result of supporting floors, etc., inside the building.

Referring now to Fig. 12, a hollow polyvinyl chloride skin 1 20 is formed as an extrusion.

The skin 1 20 is generally of channel section with a restricted mouth in which an extruded PVC closure strip 1 22 is a snap fit by means of U-section edges 1 24 which engage with the lips 1 26 of the restricted mouth.

Four lengths of the extrusion 1 20 are glued together, with mitred corners, to form a rectangular frame in which the restricted mouths in which are placed the closure strips 1 22 face outwardly. Of course, further frame members can also be included if more than one light is required in the modular frame.

The enclosed hollow tubular frame 126 thus formed from four lengths of hollow skin 120 and four lengths of closure strip 1 22 is placed in the jig shown schematically in Fig.

14. It is supported around the outside by a framework 1 28 on a baseboard 130, and on the inside it is supported by a pressure frame 1 32 (only part of which is seen in Fig. 14) which prevents the extrusion 120 bulging when it is filled.

Filling holes 1 34 are formed in the closure strip 122 which lies at the top of the frame, and a similar drain hole is formed in the strip at the bottom of the frame, to coincide with a drain hole 1 36 at the bottom of the framework 1 28. g.r.c. is then poured into the filling holes 134, and flows around the frame 126.

As soon as it starts to pour out of the drain hole 136, this hole is plugged up. This ensures that g.r.c. travelling down each side of the frame 1 26 mingles together in the region of the drain plug. The glass fibres therefore mingle well in this region so as to give good strength. Were there no drain hole 136, the fibres from each side might not intermingle, and a weakness might result.

The frame 126 is now left until the g.r.c.

sets and cures. Normally, to obtain the best and longest lasting strength characteristics of g.r.c. it is necessary for the curing to take place in a humid atmosphere. However, since the g.r.c. is substantially entirely enclosed by the skin 1 20 and closure strip 122, this is not necessary.

If desired, the closure strip 1 22 can now be pulled out and re-used in a further frame (thus saving costs). To facilitate its removal, it is extruded with lugs 1 38 by means of which it can be pulled from its snap-fit engagement with the lips 1 24. If it is not desired to remove the strip 122, it can be initially placed with the lugs 1 38 on the inside instead of the outside as shown; the lugs will then key into the g.r.c. 140.

Referring again to Fig. 12, it will be seen that the extrusion includes a recess 142 similar to the recess 78 in Fig. 9. In this recess fits a frame for a movable light as indicated by dotted lines at 144. A shallow channel 146 with a restricted mouth is provided at the edge of the recess 142 to receive a weatherproof sealing strip between the skin 1 20 and the movable light 144. The movable light 144 may be made in the same manner as the frame 126, and may have a completely enclosed tubular plastics skin.

An alternative skin extrusion 120' is seen in Fig. 13. This is similar to that seen in Fig. 12, and is used in the same way, except that instead of the recess 142 there is a similar recess 148 to accept a pane of glass and a proprietary glazing system, as in Fig. 9. A gasket is received in a shallow channel 150, and a pane of glass is pressed against this by a plastics glazing strip received in a channel 152.

The PVC skin in the various embodiments above can be relatively thin compared to known PVC frames, because the strength of the frame is provided by the g.r.c. The present frames therefore have cost advantages over all known frames except perhaps timber frames; and once the cost of painting and maintenance of timber frames have been taken into account, there are even cost savings over these.

It is well known for window frames to be supplied in bags of polyethylene or another protective plastics material. The present frames can be similarly packaged, and can be laid in the aperture in the building while still in the plastics bags. The plastics bags are then cut around the frames (leaving behind a strip of the plastics material between the frame and the building elements around the aperture). Any unsightly edges of the plastics material are covered when making good subsequently.

Although window modules have been descibed above, it is obviously possible to use the invention for other apertures in buildings, such as doors. Other materials than g.r.c.

could be used, for example glass fibre reinforced plastics, but g.r.c. is much preferred because of its good compressive loading qualities. G.r.c. is also maintenance free and has an attractive appearance.

Claims (27)

1. A method of making a frame for an aperture in a building, comprising arranging a hollow skin of plastics material to define the frame, filling the skin with a settable reinforcing composition, and allowing the settable composition to set, whereby the plastics skin acts as a mould for the settable composition and forms an outer surface for the frame.

2. A method according to claim 1 wherein the settable composition contains a fibrous reinforcing material.

3. A method according to claim 1 or claim 2 wherein the settable composition is a cementitious composition.

4. A method according to claim 1 wherein the settable composition is glass fibre reinforced cement.

5. A method according to claim 2 or claim 4 wherein the fibre-reinforced settable composition is poured into the hollow skin at an upper portion thereof and flows through the interior of the skin at each side of the frame to an outflow aperture at a lower portion thereof, and the outflow aperture is blocked after the settable composition starts to flow therefrom, whereby fibres in the settable composition flowing down the two sides of the frame intermingle in the region of the outflow aperture.

6. A method according to any one of the preceding claims wherein the hollow skin is of tubular cross-section so as substantially to enclose the settable composition as it sets.

7. A method according to claim wherein after the settable composition has set a removable portion of the tubular section of the skin is removed.

8. A method of making a frame for an aperture in a building, substantially as described herein with reference to Figs. 6 to 11 or Figs. 1 2 to 14 of the accompanying drawings.

9. A frame for an aperture in a building, having frame-forming members which comprise an outer skin of plastics material filled with a settable reinforcing composition.

10. A frame according to claim 9 wherein the settable composition contains a fibrous reinforcing material.

11. A frame according to claim 9 or claim 10 wherein the settable composition is a cementitious composition.

1 2. A frame according to claim 9 wherein the settable composition is glass fibre reinforced cement.

1 3. A frame according to any one of claims 9 to 12, wherein the plastics skin has an integral configuration which receives and retains a glazing strip for retaining a pane of glass in the frame.

14. A frame according to any one of the preceding claims, including an auxiliary frame pivoted thereto so as to be movable between an open and a closed position.

1 5. A frame according to claim 14, including a weatherproofing strip which is sandwiched between the plastics skin and the auxiliary frame when in the closed position, the weatherproofing strip being received and retained in an integral configuration in the plastics skin.

1 6. A frame for an aperture in a building, substantially as described herein with reference to Figs. 6 to 11 or Figs. 12 to 14 of the accompanying drawings.

1 7. A frame for an aperture in a building, made by a method according to any one of claims 1 to 8.

1 8. A construction for an aperture in a building, comprising two or more frames according to any one of claims 9 to 17, joined together side by side.

1 9. A construction for an aperture in a building, including a frame for the aperture, the frame having one or more vertical mem bers extending substantially from the top to the bottom of the aperture, the vertical mem ber or members being made from a load supporting material as defined herein.

20. A construction according to claim 1 9 wherein there are at least two said vertical support members, one at each side of the aperture.

21. A construction according to claim 1 8 or claim 1 9 wherein there are one or more said vertical support members at intermediate positions between the sides of the apertures.

22. A construction according to claim 21 wherein two or more modular said frames are provided in the aperture, each module having two vertical support members at its sides, the vertical support members of adjacent frames being joined together in abutment to form composite intermediate vertical support members.

23. A construction according to any one of claims 1 9 to 22 wherein the load supporting material is glass fibre reinforced cement.

24. A construction according to claim 23 wherein the glass fibre reinforced cement is moulded in a hollow plastics skin which provides an outer covering for the frame when installed.

25. A construction according to any one of claims 1 9 to 23 wherein the frame has a head member at the top thereof spanning the vertical support members to support building elements above the aperture.

26. A construction according to claim 25 wherein the head member has a flange or flanges extending forwardly and/or rearwardly to support the building elements.

27. A construction for an aperture in a building, substantially as described herein with reference to Figs. 1 to 5 of the accompanying drawings.