EP2105571A2

EP2105571A2 - Corner joint with integrated seal for a prefabricated window frame

Info

Publication number: EP2105571A2
Application number: EP09156303A
Authority: EP
Inventors: Kim Bisgaard
Original assignee: Bisgaard Industri AS
Current assignee: BISGAARD INDUSTRI A/S
Priority date: 2008-03-26
Filing date: 2009-03-26
Publication date: 2009-09-30
Also published as: DK200800438A; EP2105571A3

Abstract

The invention concerns a comer joint for a prefabricated window bordering of the kind which is composed of two vertical side panel boards (2), a horizontal superjacent panel board and a number of architraves (4) associated with the panel boards (3), and where the panel boards (3) are intended for customary letting in into grooves (8) provided therefor in the window frame (1).
Two comer joints between the superjacent panel board (3) and the two side panel boards (2) are each composed of two extruded plastic or metal edge profiles (13,14), where one edge profile (13) is fastened to the end face of the side panel board (2) in question, and the other edge profile (14) is fastened to the corresponding end face on the superjacent panel board (3). Furthermore, one edge profile (13) is provided with a groove (17) and the other edge profile (14) is provided with a projecting profiled rib (21) corresponding to this groove (17), the rib (21) adapted to by insertion into the groove (17) to lock the two edge profiles (13,14) together, e.g. by squeeze action or by a snap lock action.
The comer-profile assembly is suitably equipped with an integrated sealing system (20) consisting of a suitable elastomeric sealing material, which in highly viscous paste-like condition is laid into the profile groove (17,19). Alternatively, the sealing consists of an actual sealing strip inserted between the edge profiles (13,14). Panel boards (2,3) as well as architraves (4) are covered by plastic laminate. In that way, the window bordering immediately attains the degree of tightness required by the building regulations without additional measures. The plastic laminate covering simultaneously constitutes the vapour barrier or the moisture membrane in the building construction in and around the window niche.

Description

The present invention relates to a corner joint for a prefabricated window bordering with integrated sealing system, particularly of the kind specified in the preamble of claim 1.
In connection with building renovation and internal retro-insulation of existing buildings, it is often necessary to renew or insert new window borderings in the window openings/embrasures. By suitable retro-insulation, the window borderings will enable interruption of the heat bridges that often appear at the windows in particular. In connection with this insulation work it has hitherto been necessary to insert a moisture membrane immediately under the panel boards around the window opening. The moisture membrane has the purpose of preventing condensation in the insulation layer and of creating the required tightness in the building construction. As moisture membrane is usually used plastic film which is adapted and fitted manually in the embrasure before the panel boards are mounted. In the corners of the embrasure where different film layers overlap each other, it is necessary to tape the film layers together in order to ensure the required tightness. The solution is highly dependent on the skilled care used in the work.
Window borderings of the type mentioned here have formerly been made directly at the construction site as traditional handiwork, i.e. by manual cutting and adaptation of individual panel boards and architraves, joining and fastening these building components by means of screws, nails, glue etc., followed by filling and painting the bordering. All things together, this is a complicated and time-consuming process that raises the cost and delays the building process. The result depends highly on the ability of the skilled persons.
From the description of DK utility model BR 1999 00164 is known a prefabricated building system that enables a more rational production and mounting of the concerned elements (panel boards and architraves) forming part of a window bordering. The new feature of this building system is that all elements are prefabricated with mutually adapted corner joints and scarf joints, substantially adapted to measure in the window concerned. Furthermore in that the panel boards are prepared for mutual joining by clipping together in the corners by using a number of resilient angle braces of a type known per se, which are mounted at the external side of the panel boards, i.e. on the not visible sides of the boards, as the panel boards, or at least one part of these, are prepared with a milled transverse groove spaced apart from the corner in question. This groove serves as engagement for a hook-like projection on the angle brace directed inwardly against the panel board. The panel boards are clipped together in this way before they are inserted in the embrasure as an assembled unit, where the panel boards are inserted in a usual way in the grooves produced therefore on the internal side of the window frame.
However, the prior art building system does not solve the above mentioned problem with the moisture membrane and the need for tightness. The moisture membrane (or vapour barrier) still has to be adapted and mounted manually before mounting the panel boards, and there is a lack of certainty that the tightness required by the building regulations is achieved in the finished construction. Fitting the moisture membrane is tedious and time-consuming, requiring much care by the building worker, not the least in connection with taping the plastic film in the embrasure corners as mentioned.
Basis of the invention is the task to indicate an improved window bordering of the mentioned type which at the same time is rapid and rational to mount on the construction site and solves the said problems in connection with the moisture membrane and the tightness in the finished building construction as well. More definitely is attempted a solution where the required vapour barrier and tightness is achieved immediately in the panel construction without needing a separate moisture membrane laid in under the panel boards, i.e. a solution where the moisture membrane, so as to say, is prefabricated and integrated in the element system.
According to the invention, this is achieved by adapting the window bordering as specified in the characterising part of claim 1. The new features of the invention consist of the two corner joints between the superjacent panel board and the two side panel boards each being composed of two extruded plastic or metal edge profiles, where one edge profile is fastened to the end face of the side panel board, and where the other edge profile is fastened to the corresponding end face on the superjacent panel board. Furthermore, in that one edge profile is provided with a groove and the other edge profile is provided with a projecting profiled rib corresponding to this groove, the rib adapted to by insertion into the groove to lock the two edge profiles together, e.g. by squeeze action or by a snap lock action know per se. The two edge profiles, which are complementary, together constitute the corner in the bordering in the completely mounted condition of the window bordering.
The comer-profile assembly is suitably equipped with an integrated sealing system consisting of a suitable elastomeric sealing material, which in highly viscous paste-like condition is laid into the profile groove. Alternatively, the sealing consists of an elastomeric sealing strip inserted between the edge profiles. Panel boards as well as architraves are covered by plastic laminate. In that way, the window bordering immediately attains the degree of tightness required by the building regulations without additional measures. At the same time, the plastic lamination constitutes the necessary moisture barrier preventing formation of condensation in the insulation layer under the panel boards.
In a preferred embodiment of the window bordering according to the invention, the edge profile belonging to each side panel board is pre-fitted on the panel board. This edge profile constitutes the edge profile in the corner joint provided with groove, facing with the groove outwards in direction towards the associated superjacent panel board, which is correspondingly pre-fitted with the complementary edge profile, i.e. the edge profile provided with a rib. The rib is directed outwards from the end face of the respective panel board in direction against the groove in the opposing edge profile such that the two complementary edge profiles can be brought into engagement by simple compression or clicking together in horizontal direction, i.e. by utilising the said snap lock action between the edge profiles. In this way is achieved a very simple and rapid mounting of the panel boards at the construction site. All parts in the element system are preferably prefabricated with final dimensions such that no cutting or other kinds of adaptation have to be performed on the construction site.
The groove-rib joint is suitably designed with a certain limited displaceability in the clicking direction, i.e. into and out of the profile engagement. This displaceability provides the corner joint with a desired adaptive tolerance such that small dimensional deviations in the frame are compensated for in this way without any appreciable problems during the mounting.
In claim 6 is indicated an advantageous embodiment where the two mentioned edge profiles are mounted on respective panel boards while using hook-shaped profiled ribs which by sets retain the edge profile to the end face of the panel board. To this end, the panel board is provided with milled grooves with which the ribs are brought into squeezing or locking engagement during the making of the panel boards (prior to mounting). The rib connection may be supplemented by glue or filler according to need. In claim 7 is indicated how the rib-groove joint can be made self-locking, such that the need for additional fastening of the edge profiles to respective panel boards, e.g. by adhesive, is obviated.
The panel boards and the architraves are purposely both provided with a cover film laminate functioning both as moisture membrane in the bordering and as surface finish on the elements (claim 8). By letting the film laminate cover both front and back sides of the panel boards and the architraves, cf. claim 9, further surface treatment of the visible surfaces of the window bordering is avoided after ending mounting on the construction site. With regard to final mounting of the architraves, according to the invention it is expedient to mount these on the panel boards with key-groove joints and by using adhesive, whereby visible nail or screw holes in the architraves are avoided.
The invention will be explained in more detail in the following in connection with the drawing, where:

Fig. 1: shows a window mounted with a window bordering according to the invention, as seen from the inside;
Fig. 2: the same window shown in horizontal section along the line A-A in Fig. 1;
Fig. 3: the same window with associated bordering in exploded isometric view;
Fig. 4: an enlarged detail marked "B" in Fig. 2, showing the corner joint between the left side panel board and the superjacent panel board immediately before clicking together respective edge profiles on the panel boards;
Fig. 5: the same corner joint shown in enlarged cross-section before clicking the edge profiles together;
Fig. 6: the edge profiles shown after clicking together; and
Fig. 7: a horizontal building cross-section showing an enlarged detail of an embrasure with associated window, window bordering and insulation insert.

In the embodiment shown on the drawing where the window frame itself is indicated by 1, the window bordering mainly consists of two side panel boards 2, a horizontal superjacent panel board 3 and a set of architraves 4, see Fig. 3. The walling encircling the embrasure 1a is indicated by 5 and the sill in the embrasure by 6 (see Figs. 1 and 2). The panel boards 2 and 3 are in the usual way inserted with a rear edge key 7 into a groove 8 milled for the purpose in the window frame 1, as well as the architraves 4 are provided at the back side with a milled groove 9 intended for a front edge key 10 at the front edge of the panel boards 2 and 3, see the sectional drawing of the construction in Fig. 7. The panel boards 2 and 3 are usually made of medium-density fibreboard (MDF board) with respective front and rear edge keys 10 and 7 made by milling directly into the board edges. The architraves are made of pinewood. The panel boards and the architraves are covered with film laminate (plastic film) on both front and back sides.
As it appears from the sectional construction drawing in Fig. 7, in the embrasure 1a an insulating layer 11 is interposed between side panel boards 2 and the walling 5 itself, e.g. of mineral wool or foamed polystyrene (flamingo) such that the heat bridge at the window is broken in this way. Correspondingly, between the walling and the superjacent panel board 3, an insulating layer (not shown) is laid in. The insulating layer is outwardly closed with an elastomeric joint 12 provided between the walling 5 and the window frame 1. As all joints in the window bordering are keyed and/or glued together, a completely tight construction is achieved where the plastic lamination of the panel boards and architraves by themselves constitute a moisture blocking membrane (vapour barrier). Thus there is no need for a separate moisture membrane or vapour barrier of plastic film in the embrasure.
The panel boards 2 and 3 are joined in the two upper corners by means of special edge profiles 13 and 14 which are intended for clicking together without use of tools. This appears in more detail on Figs. 4, 5 and 6. The edge profiles 13 belongs to the side panel boards 2, and the edge profiles 14 to the superjacent panel board 3. The edge profiles are typically made by extruding a suitable thermoplastic material. Both edge profile types 13 and 14 are mounted on respective MDF panel boards by means of a set of hook-shaped profile ribs 15 and 16 which are directed towards each other, and which are intended for locking engagement in grooves 15a and 16a provided for the purpose in the MDF boards. The edge profiles are "clipped" on the boards or slid with the profile ribs 15, 16 longitudinally into the grooves 15a, 16a. In this way is achieved a self-locking connection between the edge profile and the associated panel board without further need for fastening means.
The edge profile 13 belonging to the side panel boards 2 is designed with a groove 17 facing the respective superjacent panel board 3. At the inner side, this groove is provided with a hook-like rib formation 18 facing the bottom 17a in the groove 17. The profile cavity 19 delimited by the bottom 17a and the rib 18 is filled with a plastic sealing agent, e.g. a rubber-based filler of suitable type. This adaptable "sealing strip "formed by sealing agent is indicated by 20.
The corresponding edge profile 14 which as indicated belongs to the horizontally superjacent panel board 3 is designed with a profile rib 21 directed towards the edge profile 13. The profile rib 21 is provided with a hooked profile formation 22 at the top side. The profile rib 21 is intended for locking engagement in the groove 17 in the opposing edge profile 13 by collapsing the parts, such as indicated in Figs. 5 and 6, whereby the hook 22 is brought to engage behind the rib formation 18. The elastomeric filler 20 in the profile cavity 19 will adapt to the profile rib 21 and its hooked profile formation 22, sealing the joint in that way. The design of the groove 17 and the complementary profile rib is chosen such that the parts retain a certain displaceability in the sliding direction, even in interlocked condition (see Fig. 6), such that the panel boards may easily adapt to small tolerance deviations in the window frame 1 and its groove 8. The filler 20 seals the joint under any circumstances. Use of the click-joining edge profiles 13 and 14 and their immediate adaptability to the individual window ensures optimal easiness in assembling. The sealing arrangement in the edge joints in question ensures the total tightness of the window bordering.
The invention is not limited to the embodiment shown on the drawings and described above. Other combinations of materials, other design details and other constructive solutions for the individual components of the window bordering may be envisaged within the scope of the present invention, as well as application of the principle forming the basis of the window bordering may be envisaged extended to other areas than the one indicated, e.g. door borderings. The proposed window bordering system is also applicable to new building.

Claims

A corner joint for a prefabricated window bordering of the kind which is composed of two vertical side panel boards (2), a horizontal superjacent panel board (3) and a number of architraves (4) associated with the panel boards, and where the panel boards are intended for customary letting in into grooves (8) provided therefor in the window frame (1),
characterised in that
- the two corner joints (B) between the superjacent panel board (3) and the two side panel boards (2) are each composed of two extruded plastic or metal edge profiles (13, 14), where one edge profile (13) is fastened to the end face of the respective side panel board (2), and the second edge profile (14) is fastened to the corresponding end face on the superjacent panel board (3);

- one edge profile (13) is provided with a groove (17) and the other edge profile (14) is provided with a projecting profiled rib (21) corresponding to this groove, the rib (21) adapted to by insertion into the groove to lock the two edge profiles together, e.g. by squeeze action or by a snap lock action know per se produced by an internal barb (18) in the groove and/or an external barb (22) on the profiled rib (21); and

- the two edge profiles (13, 14) are complementary and conjointly constitute the corner in the bordering in the completely mounted condition of the window bordering.
Corner joint according to claim 1, characterised in that
- the edge profile (13) belonging to each side panel board (2) is pre-fitted on the panel board;

- this edge profile (13) constitutes the edge profile in the corner joint provided with groove (17), facing with the groove outwards in direction towards the associated superjacent panel board (3);

- the superjacent panel board (3) is pre-fitted with the complementary edge profile (14), i.e. the edge profile provided with a profiled rib (21); and

- this rib (21) is directed outwards from the end face of the respective panel board (3) in direction against the groove (17) in the opposing edge profile (13), at which the two complementary edge profiles (13, 14) are positioned such in relation to each other during mounting in the embrasure that they can be brought into locked engagement by simple tool-free compression or clicking together, i.e. by utilising the said snap lock action between the edge profiles.
Corner joint according to claim 2, characterised in that the groove-rib joint (17, 21) is designed with a certain limited displaceability in the direction of displacement (i.e. into and out of the profile engagement), the displaceability providing the corner joint with a desired adapting tolerance to the window frame (1) concerned.
Corner joint according to claim 1, characterised in that the two edge profiles (13, 14) are equipped with an integrated sealing system consisting of an elastomeric or viscous sealing material (20) which is embedded in the profile groove (17), alternatively in the form of an actual sealing strip embedded in the profiled groove or in other ways between the two complementary edge profiles.
Corner joint according to claim 1, characterised in that the two edge profiles (13, 14) are extruded from a plastic material suited for the purpose, e.g. polypropylene, thermoplastic polyester, PVC or POM.
Corner joint according to claim 1, characterised in that
- the edge profiles (13, 14) are each designed with two sets of parallel hook-shaped ribs (15, 16) on the sides facing respective panel boards (2, 3);

- the panel board is provided with milled grooves (15a, 16a) on the end face and on the back side of the panel board (i.e. the side of the panel board facing the walling), which grooves being adapted to the ribs (15, 16); and

- the edge profile is fastened to respective panel boards by the engagement of the ribs in the grooves.
Corner joint according to claim 6, characterised in that the two sets of parallel hook-shaped ribs (15, 16) face each other with the hook-shaped parts of the ribs.
Corner joint according to claim 1, characterised in that the panel boards (2, 3) and the architraves (4) are provided with a cover film laminate functioning both as moisture membrane (vapour barrier) in the bordering and as surface finish.
Corner joint according to claim 8, characterised in that the panel boards and the architraves are provided with cover film laminate on both sides, i.e. both at front and back sides.
Corner joint according to claim 1, characterised in that the architraves (4) are mounted on the panel boards (2, 3) with tongue and groove joints (9).