NZ244116A - Window frame member with internal and external apertures in reveal part of the frame member for trickle ventilation of room - Google Patents

Description

24 4 7 n.z. r .. • . i'iCn 2 6 NOV 1993 received NEW ZEALAND PATENTS ACT, 1953 No.: 244116 Date: 27 August 1992 COMPLETE SPECIFICATION IMPROVEMENTS IN OR RELATING TO WINDOW VENTILATION SYSTEMS We, COMALCO EXTRUSIONS LIMITED and CARTER HOLT HARVEY ALUMINIUM LIMITED trading in partnership as COMALCO-CHH ALUMINIUM, each a New Zealand company, of, of 30-32 Bowden Road, Mount Wellington, Auckland, New Zealand hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:- 2 ^ 4 1 1 This invention is concerned with improvements in or relating to window systems. More particularly this invention is concerned with improvements in or relating to the trickle ventilation of buildings, and particularly dwellings, either private or public, by including a controllable ventilation opening in the window system.

Over the last 20 years, improvements to the air tightness of buildings have been achieved by various new products used in building construction. These products range from cladding materials, linings, roofing systems, and an increase in the use of jointing methods that reduce air leakage into the building. The joinery used in buildings has also been improved significantly in its resistance to water and air penetration. When considering heat retention in a building, one effect of this reduction in air leakage has been advantageous, that being the reduction in the cost of heating the building. However, some other effects are not advantageous.

When considering air quality, it has been established by long term testing that the air in a building such as a dwelling should be changed every two hours, that is, there should be 0.5 air changes per hour. In buildings built by modern construction methods, air change rates as low as 0.1 air changes per hour have been recorded when windows have been closed. The result of this is to cause poor quality air grades for human habitation. The most visible result of low air change rates is condensation which forms on cold surfaces such as the surfaces of glass, aluminium window frames, and interior linings. Heavy rates of condensation can be seen where water is introduced into a room by respiration, burning of fuels such as gas in stoves, and steaming hot water.

If air which is too moist is not removed from a building, that passing over any cold surfaces will deposit moisture onto those surfaces. Often the surfaces will be those of glass windows or aluminium joinery which are not - 3 - 4 1 1 damaged by the moisture although it may appear unsightly. Less visible but more insidious is the condensation depositing on walls and ceilings. The effects of this may be mildew build-up, wall-paper falling off, and rotting of wooden window liners.

To help improve the quality of air in buildings various methods are available. Dehumidifiers can be used but can be expensive to buy and operate. One way of improving the air quality is to increase the rate of air change up to the recommended 0.5 air changes per hour. There are various ways this can be achieved, one way being the provision of trickle ventilation systems in windows. An object of the present invention is to provide a novel trickle ventilation system for a window.

In the art there is a difference between trickle ventilation as opposed to comfort ventilation. Comfort ventilation is intended primarily to control heat build-up in the building or dwelling as well as improve air quality and avoid staleness. For example, comfort ventilation opening area would typically be in the order of two to ten square metres per house. Trickle ventilation is intended to provide a small air flow into the building or dwelling compared to comfort ventilation. For example, trickle ventilation opening area is typically recommended at 0.03 to 0.04 square metres per house.

Security also has to be considered in ventilation systems because just leaving a window slightly open is not secure, and special window handles that enable a window to be open 5 to 10 millimetres but still held closed by a secondary latch are not as secure as many people would like. This has led to ventilators providing for trickle ventilation becoming more popular.

Up till now most ventilators for providing trickle ventilation have comprised a unit which is added to the window. Typically, during the assembly of the window, a pre-assembled ventilation unit is added as part of the window, whether this be a sash window or a fixed light window, the unit being inside the window frame. To fit these units into the window the glass is cut smaller 24 4 1 H by the amount required to fit the unit. Disadvantages of such ventilation units can include factors such as complexity and cost.

Another type of trickle ventilation system for a sash window has had ventilation holes provided in the sash bottom rail. While the ventilation holes can be shut off there is still a risk of water being blown by the wind inwardly through the ventilation holes when they are open. The source of some of this water is any water sitting on the sill or transom as the case may be over which the sash bottom rail is located when the sash window is closed.

When a product is part of the window supplied to the New Zealand market it has to pass tests regulated by the New Zealand Standards Association. The standard for windows is NZS 4211:1985. Part of this standard provides for a water test which requires a prototype window to be tested to varying degrees of water tightness.

An object of the present invention is to achieve, for at least the preferred embodiments of the invention, the 1100 Pascal rating which is summarised as follows: 1. The window is fitted into a test rig. 2. The rig is pressurised to 0.3 x 1100 Pascals = 330 Pascals and the unit is sprayed with water. 3. The pressure on the outside of the window is increased in four stages: i) 82.5 Pascals for two minutes; ii) 165 Pascals for two minutes; iii) 247 Pascals for two minutes; iv) 330 Pascals for ten minutes.

The full test takes 16 minutes and to achieve the rating, no water shall enter past the aluminium window frame onto the wooden liner during that time.

In a first aspect the present invention consists in a ventilation frame - 5 ijj o tj_ u.

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CO IT) CM 2^4 1 1 member for an outer fixed frame of a window, the frame member having ventilation means for permitting a sufficient air flow through the frame member from an external side of the window to an internal side of the window, or vice versa, to provide for trickle ventilation of a room in an exterior wall of which the window is installed in use.

The frame member is preferably an extruded member, more preferably an extruded aluminium member.

The ventilation means comprises a plurality of external apertures located on an outer side of the frame member, a plurality of internal apertures located on an inner side of the frame member and a cavity towards a rear side of the frame member providing a fluid pathway connecting the external and the internal apertures. Preferably the external apertures and/or the internal apertures are located in a surface on their respective side of the frame member which surface lies substantially perpendicular to the plane of the window with the external apertures being spaced at intervals along at least a substantial portion of the length of the frame member and the internal apertures being spaced at intervals along a substantially corresponding portion of the length of the frame member. Usually there will be an internal aerture opposite each external aperture with all apertures preferably being substantially the sfeme size.

It is desirable for the ventilation means to include an insect screening Q 1X1 > LJ o amkans, this being associated with the external apertures of the frame member.

Ie preferred insect screening means comprises a single insect screen extending ong and secured to the frame member over the external apertures.

It is also desirable for the ventilation means to include a ventilation controlling means enabling the ventilation means to be opened or closed to air flow therethrough, this preferably being associated with the internal apertures of the frame member and being operable from the inner side of the frame member to open and close the internal apertures. The preferred ventilation controlling means comprises a manually operable slide memb&r mounted to the 24 4 1 1 frame member over the internal apertures and having slide apertures preferably substantially corresponding in number, size and spacing to the internal apertures, the slide member being slidable from an open position where the slide apertures are aligned with the internal apertures of the frame member and a closed position where the slide apertures are out of alignment with the internal apertures which are thereby blocked by the slide member. The ventilation controlling means may include securing means to secure the slide member in its open position and in its closed position.

The cavity preferably comprises a substantially channel-shaped recess in the rear side of the frame member extending lengthwise along the frame member and this cavity is preferably enclosed by cavity closure means. The cavity closure means may comprise a cover over the channel and an end cap in the channel at each end of the cover and in this case the cavity is preferably sealed on the rear side of the frame member by a sealant applied to gaps or joins between the cover, the end caps and the rear side of the frame member.

In a second aspect the present invention consists in an outer frame for a window including a ventilation frame member as defined above.

A standard window frame typically comprises a head, a sill, and two opposite jambs, and according to the invention at least one of the head and the jambs comprises a said ventilation frame member. It is preferable that the frame sill does not comprise a ventilation frame member.

The ventilation means of the or each ventilation frame member will usually be positioned adjacent an opening provided for a sash window but alternatively, or as well, the ventilation means of the or each ventilation frame member may be positioned adjacent an opening for a fixed light. In this latter case a bead which secures the fixed light may be provided with one or more bead apertures allowing air flow to or from the external apertures of the ventilation frame member. In this latter case also, it is particularly preferred that the ventilation frame member comprises the head of the window 2i>4; i6 frame, whereas, in the case of a sash window it is particularly preferred that either one or both of the jambs comprise a ventilation frame member.

In a third aspect the present invention consists in a window having an outer frame as defined above.

In a fourth aspect the present invention consists in a window frame suitable for fixed installation in a wall of a building, the window frame, which is preferably also suitable for a sash window, having elongated extruded frame members comprising a head, a sill and two opposite jambs, at least one frame member excepting the head or the sill comprising a ventilation frame member incorporating ventilation means for permitting a sufficient air flow through the frame member from an outer side of the window frame to an inner side of the window frame, or vice versa, to provide for trickle ventilation of a room in the building, the ventilation means comprising a plurality of apertures arranged on the outer side of the frame member along at least a portion of its length, a plurality of apertures arranged on the inner side of the frame member along at least a portion of its length, a substantially enclosed cavity extended lengthwise on a rear side of or within the frame member and providing a fluid pathway connecting the outer and the inner apertures; and ventilation controlling means mounted to the ventilation frame member for enabling the internal apertures and/or the external apertures of the ventilation means to be opened or closed to air flow therethrough.

The above broadly defines the present invention, some preferred forms of which will now be described with reference to the accompanying drawings in which: Figure 1 shows an elevation of a sash window; Figure 2 shows an elevation of a window comprising an upper sash and a lower fixed light; Figure 3 shows an elevation of a window comprising, at the right hand end, an upper sash and a lower fixed light and, at the left hand end, a large fixed light; Figure 4 is a view on IV-IV of Figure 1, showing a cross-section through 24 4 1 1 6 only the jamb of the outer frame of a sash window and also showing an end cap prior to being fitted into the channel-shaped recess in the rear side of the frame jamb; Figure 5 shows an isometric view of two end caps and the cavity cover which is shown fitted to one of the end caps; Figure 6 is a view on VI-VI of Figure 1, showing a cross-section through the frame sill and an elevation of the lower end of the left hand frame jamb, these forming parts of the outer frame for a sash window; Figure 7 is a view on VII-VII of Figure 2, showing an elevation of the left hand frame jamb and a cross-section through the transom above which the sash will be located and below which the fixed light will be located in the complete window installation; Figure 8 shows a plan view of a slide member; ' Figure 9 shows an end view of the slide member; Figure 10 is a view substantially corresponding to that of Figure 4 but showing the end cap in position, showing a vent stop for the slide member in position, and indicating how the slide member is fitted into position; Figure 11 is a view on XI-XI of Figure 1, showing a cross-section through the frame sill and an elevation of the right hand frame jamb with two vent stops attached; Figure 12 is a view corresponding to that of Figure 11 (with the vent stops omitted) showing the fitting of the insect screen over the outer apertures of the frame member; and Figure 13 is a view of the frame member (a frame jamb) corresponding to that of Figures 4 and 10 but showing the frame member installed in a window opening in the wall of a building and also showing in section the right hand end of a sash window in its closed position.

The trickle ventilation system of the present invention is incorporated 24 4 1 16 in the outer frame of a window. According to a preferred embodiment of the invention the ventilation system is incorporated in the outer frame of a sash window. The sash window can be mounted to be pivotal or slidable relative to the outer frame. In the drawings, stays, hinges and catches are, for simplicity, not shown. Furthermore, in preferred embodiments of the invention the ventilation system is incorporated in the outer frame head and/or one or both of the outer frame jambs of a window. It is preferable not to have the ventilation system incorporated in the outer frame sill to reduce the possibility of the ingress of water through the ventilation system. For a sash window it is particularly preferred to have the ventilation system incorporated in one or both jambs of the window frame. Compared with having it in the head, this provides better access for users who might want to adjust the ventilation. Furthermore, when curtains are used with the window these, even when open, will usually conceal the ventilation system from view from the inside of the window. The invention will be particularly described with reference to a sash window having the ventilation system incorporated in an outer frame jamb.

Figure 1 shows an elevation of a sash window 10. The sash window has an outer frame 12: In use the outer frame is installed in a window opening provided in a wall of a building. The outer frame comprises a frame head 14, hereinafter called a "head", a frame sill 16, hereinafter called a "sill", and two frame jambs 18 and 20, hereinafter called "jambs". The completed window also has a sash frame 22 comprising a top rail 24, a bottom rail 26 and two stiles 28 and 30 which enclose a glass pane 32. The members of the outer frame 12 and of the sash frame 22 are all preferably made from aluminium extrusions cut to length, mitred at their ends, and joined together by screws in known manner.

Figure 2 shows a view similar to that of Figure 1, and like parts are given like numbering, except that the window has a fixed light 34 below the sash window 10. The jambs 18 and 20 extend the full height of the window and 24 4 116 the sill 16 is located across the bottom of the fixed light. The fixed light is separated from the opening in the outer frame in which the sash window is fitted by a transom 36. The transom is also preferably made from a length of extruded aluminium though the extrusion is usually different in type from that used for the outer frame members or the sash frame members.

Figure 3 shows a view similar to that of Figure 2, with like parts again being given like numbering, except that the window has a large fixed light 38 at its left hand end. The head 14 and the sill 16 of the outer frame are extended to the left and are joined by the jamb 18 at the left hand end of the fixed light 38. The fixed light 38 is separated from the fixed light 34 and from the opening in the outer frame in which the sash window is installed by a mull ion 40. The mull ion is preferably made from a length of extruded aluminium and can be the same type of extrusion as that used for the transom 36.

Figure 4 shows a cross-section through a frame member, being the jamb 20, looking towards the sill 16 which extends to the left. As already mentioned, the jamb is preferably made from an aluminium extrusion cut to an appropriate length. The other members of the outer frame are preferably made from the same type of extrusion. The particular shape of the extrusion shown in Figure 4 is merely illustrative; extrusions of other shapes can be used to make the outer frame.

The frame member comprising the jamb 20 has an outer flange 42 and an inner L-shaped securing flange 44 joined by a web 46. These flanges and the web form a generally channel-shaped recess 48 on the rear side of the frame member. The web 46 is divided into an outer web 46a and an inner web 46b by a flange 50 projecting generally oppositely from the flanges 42 and 44. At the inner end of the inner web there is a second L-shaped securing flange 52. The securing flanges 44 and 52 together define a channel 54 in which the edge of a window liner, usually made of wood, can be fitted. A window liner 56 is 24 4 1 1s shown fitted to the channel 54 in Figure 13.

The securing flange 52, together with the inner web 46b and the flange 50 defines another channel 58. When this type of extrusion is used to make a sill 16, the channel 58 of the sill can be used as a condensation collection channel.

The jamb 20 shown in Figure 4 has ventilation means for permitting a sufficient air flow for trickle ventilation through the frame member from an external side of the window to an internal side of the window, or vice versa. The ventilation means comprises an external aperture 60 1n the outer web 46a, an internal aperture 62 in the inner web 46b, and a cavity providing a fluid pathway connecting these apertures, this cavity being provided by the recess 48 on the rear side of the frame member. If the frame member were tubular then the cavity could be the hollow within the frame member. While there could be only one external aperture and one internal aperture, these would usually have to be considerably elongated to provide a sufficient area for satisfactory trickle ventilation and this would have the effect of weakening the frame member. Therefore it is preferred that the ventilation means comprises a plurality of external apertures 60 and a plurality of internal apertures 62 connected by the cavity. This is shown in Figures 6, 7, 11 and 12 where the external apertures 60 are spaced at intervals along at least a substantial portion of the length of the frame member and the internal apertures 62 are likewise placed at intervals along a substantially corresponding portion of the length of the frame member. The words "along at least a substantial portion of the length of the frame member" do not necessarily mean along a major part of the length of the frame member. The length of the frame member having the apertures depends on factors such as the type of window involved, the total length of the frame member, the number of frame members in the window outer frame being provided with the ventilation means, the number of windows in a room provided with the ventilation means, and the total aperture area required 24 4 1 f for effective trickle ventilation which will depend on the size of the room or dwelling. In Figure 7 the apertures are not shown to continue below the transom 36 where a fixed light will be fitted in the completed window installation.

As shown in Figures 6, 7, 11 and 12, there is preferably an internal aperture 62 opposite each external aperture 60 and all apertures are preferably of substantially the same size.

Because it is possible for water to be blown in through the external apertures or for condensation to occur to the rear side of the frame member, this, when used as a jamb, is preferably provided with a drainage hole 64 in the outer web 46a at or towards its lower end where it meets a sill 16 or at or towards the intersection with a transom 36. These drainage holes are shown in Figures 6, 7, 11 and 12. Where the frame member having ventilation means comprises a head there is no need for any drainage hole 64.

The apertures 60 and 62 will usually be of a size such that it is possible for larger insects such as flies, bees and mosquitos and other creatures such as spiders, slaters and cockroaches to pass through the ventilation means. To prevent this, the preferred ventilation means includes an insect screening means. It is desirable that the insect screening means is associated with the external apertures 60 of the frame member to prevent insects and other creatures from even getting into the cavity on the rear side of the frame member. The preferred insect screening means comprises a single insect screen 66 extending along the frame member over the external apertures. Figure 12 shows such an insect screen being slid into position (though this would be done before the attachment of the jamb 20 to the sill 16). Opposite edges of the insect screen are engaged in slots 68 and 70 formed in the extrusion on the outer and inner sides of the outer web 46a; see also Figure 13. The insect screen can in fact provide a distinctive visual feature of the outer frame. It can be made of a metal or plastics mesh and be of the same or different -13 - 24 4 1 7 colour compared with the frame member to which it is fitted.

Particularly in cold or inclement weather it may be desirable to prevent trickle ventilation through the ventilation means. For this purpose the preferred ventilation means includes a ventilation controlling means enabling the ventilation means to be opened or closed to air flow therethrough. The ventilation controlling means is preferably associated with the internal apertures 62 of the frame member and is operable from- the inner side of the frame member.

The preferred ventilation controlling means comprises a manually operable slide member 72 as shown in plan and end views in Figures 8 and 9. In the embodiment of the invention shown, the slide member is substantially channel-shaped, being designed to fit into and be slidable back and forth in the channel 58 of the frame member. Figures 9 and 10 viewed together show the positioning of the slide member ready for fitting to the frame member and Figure 13 shows the slide member when fitted. As also shown in Figure 13, one flange 74 of the slide member projects clear of the frame member channel 58 so that it provides a grip for a person wishing to move the slide member between open and closed positions. The outer face of each flange of the slide member preferably has a groove 75 which slidably engages with a matching rib 76 in the frame member channel 58. The slide member is preferably made from a resilient plastics material. These features enable the slide member to be snapped into position in the channel 58 and to be deliberately, but not inadvertently, removed therefrom.

The web 78 of the slide member has a plurality of apertures 80 which substantially correspond in number, size and spacing to the internal apertures 62 of the frame member 20. The slide member is slidable front an open position where the slide apertures are aligned with the internal apertures 62 of the frame member and a closed position where the slide apertures are out of alignment with the internal apertures which are thereby blocked by the slide 24 4 1 16 member. ^ The ventilation controlling means preferably includes securing means to secure the slide member in its open position and in its closed position. In Figure 11 two vent stops 82 are fitted in the frame member channel 58 and held in place by screws 84. Usually the vent stops 82 would be located further apart than shown with more than three internal apertures 62 between them. Each of the vent stops, which are preferably made from a resilient plastics material, has a tongue 86 spaced just sufficiently from the channel 58 to permit an end of the slide member 72 to be held between the tongue and the channel in a frictional fit. The slide member is cut or made shorter by one aperture than the distance between the vent stops 82 to permit the slide member to be slid between open and closed positions. Of course, if there is sufficient frictional resistance to the slide member being slid in the channel 58 anyway then it might be decided that the vent stops 82 need not be used.

The cavity provided by the channel-shaped recess 48 on the rear side of the frame member is preferably enclosed by cavity closure means. The preferred cavity closure means comprises an elongated cover 88 over the recess and an end cap 90 in the recess at each end of the cover; see Figures 4, 5, 10 and 13. The cover is preferably made from aluminium though can be made from a plastics material whereas the end caps are preferably made from a plastics material. The ends of the cover are pressed into slots 92 provided in the end caps as shown in Figure 5. The end caps are clipped or slid into position in the recess 48, a wedge-shaped recess 94 in each end cap engaging with a matching wedge projecting from the web 46 on the rear side of the frame member and a groove 98 in an end of each end cap engaging with a rib 100 on the inside of the outer flange 42; see Figure 4. The completed assembly is shown in cross-section in Figure 13. The cavity recess 48 is preferably sealed to the rear side of the frame member by a suitable sealant 102 applied to any gaps or joins between the cover 88, the end caps 90, and the rear side of the frame member. 24 4 1 1 $ This prevents any moisture which is carried through the external apertures 60 into the cavity from making contact with the building structure 104, which may be made of wood, surrounding the outer frame of the window. This also ensures that the ventilation air comes only from the sash cavity 114 (see Figure 13) and not from the sill of the window which, if it did, could carry water with it.

Figure 13 also shows part of a glazed sash window frame in its closed position. An inner face 106 of the sash stile 30 contacts a seal 108 carried by the flange 50 of the frame member. However, the outer flange 110 does not contact the frame member 20; there is a small gap 112 through which air can pass into the sash cavity 114 and thence through the ventilation means of the frame member as indicated by the arrows A provided that the vent slide member 72 is in its open position. From Figure 13 it can be seen that 1f the frame member comprised a sill then much of any water carried into the sash cavity would pass through the external apertures into the cavity at the rear of the frame member, this thereby increasing the possibility of water being carried through the internal apertures as well. This is a reason why the ventilation means of the present invention is preferably not incorporated in a sill. Nevertheless, it can be seen in Figure 13 that the external apertures 60 do receive a degree of weather protection from the sash stile 30 when the sash window is closed and this is another preferred feature of the invention. The gap is preferably offset relative to the external apertures in order to assist in preventing rainwater entering the external apertures.

The invention has been particularly described with reference to a sash window. However, the outer frame, and preferably the head and/or one or both jambs thereof, of a fixed light can be provided with such ventilation means. In this case the glass 116 and the bead 118 shown fitted to the sash stile 30 in Figure 13 would instead be fitted directly to the frame member forward of its flange 50. In this case there would need to be one or more apertures 116 provided in the bead to allow air flow to and from the external aperture 60. The insect screen could be mounted inside the bead. Because of the presence of ventilation holes in the bead, this type of window preferably has the ventilation means in only the head of the window frame for better protection against possible ingress of rainwater.

The above has described some preferred embodiments of the invention and indicated various possible modifications. However, other modifications can be made within the scope of the invention as has been defined in the following claims. However, it is a feature of the invention that in any embodiment there is no sub-frame which is added to the window. Furthermore, in preferred embodiments, windows having the ventilation means of the present invention will pass the 1100 Pascal water test with the ventilation means open when the ventilation means is provided in the head and/or one or both jambs of a window. n.z. p.ATr.MT or-Ticr; j 2 5 NOV 199B ! 17 -

Claims (52)

WHAT WE CLAIM IS:

1. A ventilation frame member for an outer fixed frame of a window, the frame member having ventilation means for permitting a sufficient air flow through the frame member from an external side of the window to an internal side of the window, or vice versa, to provide for trickle ventilation of a room in an exterior wall of which the window is installed in use; wherein the ventilation means comprises a plurality of external apertures located on an outer side of the frame member, a plurality of internal apertures located on an inner side of the frame member, the external apertures and/or the internal apertures being located in a surface on their respective side of the frame member which surface lies substantially perpendicular to the plane of the window, and a cavity towards a rear side of or within the frame member providing a fluid pathway connecting the external and the internal apertures.

2. A frame member according to claim 1 wherein the frame member is an extruded aluminium frame member.

3. A frame member according to claim 1 or 2 wherein the cavity comprises a substantially channel-shaped recess in the rear side of the frame member extending lengthwise along the frame member.

4. A frame member according to claim 3 wherein the cavity is enclosed by cavity closure means.

5. A frame member according to claim 4 wherein the cavity closure means comprises a cover over the channel and an end cap in the channel at each end of the cover. - 18- (followed by page -18a-)

6. A frame member according to claim 5 wherein the cavity is sealed on the rear side of the frame member by a sealant applied to gaps or joins between the cover, the end caps and the rear side of the frame member.

7. A frame member according to any one of the preceding claims wherein the external apertures are located in an external rebate of the frame member.

8. A frame member according to any one of the preceding claims wherein the internal apertures are located in an internal rebate of the frame member.

9. A frame member according to claim 7 or 8 wherein the surface of the rebate which is substantially perpendicular to the plane of the window comprises a web portion of the frame between the inner and outer sides of the frame.

10. A frame member according to any one of the preceding claims wherein the external apertures are spaced at intervals along at least a major portion of the length of the frame member and the internal apertures are spaced at intervals along a substantially corresponding portion of the length of the frame member.

11. A frame member according to claim 10 wherein there is an internal aperture opposite each external aperture.

12. A frame member according to any one of the preceding claims wherein the external apertures and the internal apertures are substantially the same size. 0

13. A frame member according to any one of the ventilation means has an insect screening means. 2 5 NOV 1996 received 116 - 18a-

14. A frame member according to claim 13, wherein the insect screening means screens the external apertures of the frame member.

15. A frame member according to claim 14 wherein the insect screening means comprises a single insect screen extending along and secured to the frame member over the external apertures. *•—116

16. A frame member according to any one of the preceding claims wherein the ventilation means includes a ventilation controlling means enabling the ventilation means to be opened or closed to air flow therethrough.

17. A frame member according to claim 16 wherein the ventilation controlling means cooperates with the internal apertures of the frame member and is operable from the inner side of the frame member to open and close the internal apertures.

18. A frame member according to claim 17 wherein the ventilation controlling means comprises a manually operable slide member mounted to the frame member over the internal apertures and having slide apertures, the slide member being slidable from an open position where the slide apertures are aligned with the internal apertures of the frame member and a closed position where the slide apertures are out of alignment with the internal apertures which are thereby blocked by the slide member.

19. A frame member according to claim is wherein the slide apertures substantially correspond in number, size and spacing to the internal apertures.

20. A frame member according to claim 18 or claim 19 wherein the ventilation controlling means includes securing means to secure the slide member in its open position and in its closed position.

21. A frame member according to claim 1 and substantially as herein described with reference to any embodiment shown in the accompanying drawings.

22. An outer frame for a window including a venti according to any one of the preceding claims. ntinn framft mpmbgr n.z. paff-ni' ■ 2 5 NOV 1996 received

23. A window frame according to claim 22 wherein the outer frame comprises a head, a sill, and two opposite jambs, and at least one of the head and the jambs comprises a said ventilation frame member.

24. A window frame according to claim 23 wherein the sill does not comprise a ventilation frame member.

23. A window frame according to any one of claims 22 to 24 wherein the ventilation means of the or each ventilation frame member is positioned adjacent an opening provided for a sash window.

26. A window frame according to claim 25 when dependent on claim 23 wherein neither the head nor the sill comprises a ventilation frame member.

27. A window frame according to any one of claims 22 to 24 wherein the ventilation means of the or each ventilation frame member is positioned adjacent an opening defined by the frame for a fixed light.

28. A window frame according to claim 27 wherein a bead which secures the fixed light in the frame is provided with one or more bead apertures allowing air flow to or from the external apertures of the ventilation frame member.

29. A window frame according to claim 28 wherein only the head of the frame comprises a ventilation frame member.

30. A window frame substantially as herein described with reference to any embodiment shown in the accompanying drawings. N.Z. PATENT o- ■ 2 '5 NOV 1996 F'X"L ivec -21 -

31. A glazed window having an outer frame according to any one of claims 22 to 30.

32. A glazed window substantially as herein described with reference to any embodiment shown in the accompanying drawings.

33. A window frame for fixed installation in a wall of a building, the window frame having elongated extruded frame members comprising a head, a sill and two opposite jambs, at least one frame member excepting the head or the sill comprising a ventilation frame member incorporating ventilation means for permitting a sufficient air flow through the frame member from an outer side of the window frame to an inner side of the window frame, or vice versa, to provide for trickle ventilation of a room in the building, the ventilation means comprising a plurality of apertures arranged on the outer side of the frame member along at least a portion of its length, a plurality of apertures arranged on the inner side of the frame member along at least a portion of its length, a substantially enclosed cavity extended lengthwise on a rear side of or within the frame member and providing a fluid pathway connecting the outer and the inner apertures; and ventilation controlling means mounted to the ventilation frame member for enabling the internal apertures and/or the external apertures of the ventilation means to be opened or closed to air flow therethrough.

34. A window frame according to claim 33 wherein the cavity comprises a substantially hannel-shaped recess in the rear side of the or each ventilation frame member which recess is substantially enclosed by a cover over the recess and an end cap in the recess at each end of the cover.

35. A window frame according to claim 34 wherein the cavity is sealed on the rear side of the ventilation frame member by a sealant applied to gaps or joins between the cover, the end caps and the rear side of the ventilation frame member. 116

36. A window frame according to any one of claims 3 ? to 35 wherein the external apertures and/or the internal apertures are located in a surface on their respective side of the ventilation frame member which surface lies substantially perpendicular to the plane of the window.

37. A window frame according to any one of claims 33 to 36 wherein the apertures on the outer side of the ventilation frame member are located in an external rebate of the ventilation frame member.

38. A window frame according to any one of claims 33 to 37 wherein the apertures on the inner side of the ventilation frame member are located in an internal rebate of the ventilation frame member.

39. A window frame according to claim 37 or 38 (when dependent on claim 36) wherein the surface of the rebate which is substantially perpendicular to the plane of the window comprises a web portion of the frame between the inner and outer sides of the frame.

40. A window frame according to any one of claims 33 to 39 wherein the ventilation controlling means cooperates with the inner apertures of the ventilation frame member and is operable from the inner side of the ventilation frame member to open and close the inner apertures.

41. A window frame according to claim 40 wherein the ventilation controlling means comprises a manually operable slide member mounted to the ventilation frame member over the inner apertures and having slide apertures, the slide member being slidable from an open position where the slide apertures are aligned with the inner apertures of the ventilation frame member and a closed position where the slide apertures are out of alignment with the inner apertures which are thereby blocked by the slide member. » -23-

42. A window frame according to any one of claims 33 to 41 wherein the ventilation controlling means includes securing means to secure the slide member in its open position and in its closed position.

43. A window frame according to any one of claims 33 to 42 wherein the ventilation means has an insect screening means.

44. A window frame according to claim 43 wherein the insect screening means comprises a single insect screen extending along and secured to the frame member over the external apertures.

45. A window comprising a window frame according to any one of claims 22 to 30 and 33 to 44 wherein a sash window comprising a sash frame in which glazing is fitted is mounted to the window frame.

46. A window according to claim 45 wherein the sash frame is pivotally mounted to the window frame whereby the sash window can be swung between open and closed positions.

47. A window according to claim 46 wherein when the sash window is closed the sash frame at least partly overlies the ventilation frcfne member and together with the frame member defines a sash cavity to which the outer apertures of the ventilation means open, the sash cavity also being open to the atmosphere via a gap between an outer part of each of the sash frame and the ventilation frame member.

48. A window according to claim 47 wherein the gap is offset relative to the outer apertures so that there is no straight path between them in order to reduce or prevent the possibility of rainwater entering the outer apertures. -24 - ^4 7 7 t.

49. A window comprising a window frame according to any one of claims 22 to 30 and 33 to 44 wherein a fixed light is mounted in the window frame.

50. A window according to any one of claims 45 to 49 wherein the window meets the 1100 Pascal rating as set out in NZS 4211:1985.

51. A window according to any one of claims 45 to 50 wherein the window is fixedly installed in a wall of a building.

52. A window frame according to any one of claims 22 to 30 and 33 to 44 wherein the window frame is fixedly installed in a wall of a building. By the authorised agents N.Z. PAi OFFICE 2 5 NOV 1996 RECEIVED