GB2193513A

GB2193513A - A channel and wall tie

Info

Publication number: GB2193513A
Application number: GB08619114A
Authority: GB
Inventors: Roger Townsend
Original assignee: Harris & Edgar Ltd
Current assignee: Harris & Edgar Ltd
Priority date: 1986-08-05
Filing date: 1986-08-05
Publication date: 1988-02-10
Also published as: GB8619114D0

Abstract

A channel 1 has a rear portion 2 and two arms 3 forming opposing grooves 4 for holding a wall tie 8 in locking engagement. The ratio of interior width (B) to interior depth (A) of the channel is between 6 and 10, and preferably substantially 8. A wall tie 8 has a head portion 9 and resiliently sprung feet 10 which may be inserted into the channel 1 between the arms 3 and twisted into the grooves 4. The position of the wall tie 8 is infinitely variable in the channel 1. <IMAGE>

Description

SPECIFICATION A Channel and wall tie This invention relates to a channel and wall tie for tying in new walls to existing, new or previously constructed walls.

It is common practice to build extensions to existing buildings and to relocate interior walls. Building regulations and British Stan dards require that new walls are secured to existing walls and this is often achieved by removing some of the existing brick- or blockwork and inserting new bricks or blocks as a joint between the two walls. This can be detrimental to the soundness of the existing wall and has been made difficult by the introduction of metric-sized bricks and blocks. Dovetail channels provide a method of allowing wall ties to be used between concrete structures and cladding where the channels must be cast into the concrete structural wall. These channeis are therefore unsuitable for adding a new brick or block wall to an existing one.

Profiles are now known which may be fixed to existing walls and to which a new wall may be tied at fixed intervals. These profiles have many perforations and shapings which must be manufactured into the profile, making production difficult. Additionally, the means by which the ties are fixed to the profiie allow limited variation in the positioning of the ties.

An object of the invention is to provide a channel for accommodation of a wall tie such that the variation in positioning of the wall tie is unlimited.

The invention provides a channel for holding a wall tie in locking engagement having a rear portion and two arms spaced from the rear portion to form opposed grooves, wherein the interior width of the rear portion is a plurality of times larger than the interior depth of the grooves, so that a wall tie may be inserted into the channel between the arms and held on twisting in any desired position by locking engagement with the grooves.

The channel may be screwed to an existing wall, floor or ceiling along the line of the proposed join with the new wall. Ties are then inserted into the channel as the new wall is built, the ties being unlimitedly adjustable in the channel in order that ties may be embedded in mortar joints of the new wall at appropriate intervals. The channel is preferably of such dimensions that it may be embedded in a mortar joint at the join between the two walls. British Standards state that the average joint thickness is 10mum.

The above method of tying a new wall to an existing wall provides a firm fixing in all directions other than that parallel to the longitudinal axis of the channel. Limited movement is allowed in this direction such that when a vertical channel is used, differential settling of the two walls is accommodated without allowing the walls to part at the join. Further advantages of this method lie in the fact that the variation in distance between a wall and cladding may be made as small as possible, and that the need for large, heavy, expensive angle supports is obviated.

The channel may be used in lengths equal to a 3.5m storey-height, or equally in shorter lengths. Lengths may be formed into shaped sections at low cost and short lengths may be plugged or crimped at each end to prevent concrete entering the channel and further restricting the limited longitudinal movement of the ties. Holes for receiving screws or other fixing means are preferably located in the rear of the channel in order to facilitate fastening of the channel to the wall. Further anchorage of a channel length to a wall may be achieved by inserting a strip or plate through an outwardly deformed portion of the rear portion of the channel and embedding the channel into the cast concrete wall. The strip may be bent to facilitate embedment into concrete.Alternatively, a wire anchor may be inserted at either or both ends of the channel or into an outwardly deformed portion of the rear portion of the channel where the tie is snap-fittable into position. This facility obviates the need for welding anchors to the rear of the channel which is undesirable and costly.

The invention also provides a fitting for use with a channel as described above, having holding means whereby the fitting may be inserted into the channel between the arms and brought into locking engagement with the grooves by twisting of the fitting relative to the channel.

The fitting may be a wall tie having a head portion and resiliently sprung feet which form the holding means. The head and feet are preferably coplanar, although different formations are possible. The feet, for example, may be coplanar but perpendicular to the head. In order to form a firm fixing between the feet and the groove, the exterior depth of the feet is substantially the same as the interior depth of the grooves. Where the wall tie is formed from a single shaped length of wire, as is preferred, the ends of the wire may be turned outward to form the feet. The diameter of the wire may therefore be substantially the same as the interior depth of the grooves in order to achieve a firm fixing of the feet therein.

Alternatively, the diameter of the wire may be smaller than the interior depth of the grooves and the feet may therefore be shaped in order to achieve the correct exterior depth of the feet.

The length of the feet, and therefore the interior width of the rear portion, must also be substantially greater than the exterior depth thereof in order to achieve firm fixing of the fitting in the channel and reduce the risk of inadvertant disengagement. A ratio of between 6 and 10 of interior width of the rear portion to interior depth of the grooves is preferable and a similar ratio of approximately 8 is particularly desirable. The feet may be arranged such that when the wall tie is in locking engagement with the channel, the head portion may be parallel or perpendicular to the longitudinal axis of the channel.

The wall tie may equally be formed from a flat plate, e.g. steel plate. A flat tongue is then provided which is embedded in the mortar joints between brick- or block-work courses. The tongue may be partially divided by a longitudinal notch in order to improve the fixing of the tie to the new wall. The feet, which are not resiliently sprung, are shaped out of the same plate as the tongue and are interlockingly engageable with the grooves upon twisting of the wall tie. The feet may also have notches lockingly engageable with the arms of the channel.

Under certain circumstances, it is desirable to allow a further degree of freedom other than the single one mentioned above; i.e. parallel to the longitudinal axis of the channel. For example; when the channel is fixed to a ceiling in order to suspend a partition wall, it is necessary to allow vertical displacement between the ceiling and partition. In order to allow such displacement, a wall tie having a substantially rectangular tongue is provided, together with a sleeve of flexible material. The sleeve is arranged over the wall tie and embedded into the mortar joint so that displacement may occur between the sleeve and the wall tie.

A further possible fitting is a bolt having an apertured plate which is insertable into the channel from the front and lockingly engageable with the grooves such that the bolt may be held in any desired position along the channel. The aperture may further be screwthreaded such that relative displacement of the bolt to the plate brings the plate into contact with the arms while bracing the bolt head against the rear portion of the channel. In this way, the bolt may be locked into any desired position along the channel.

Embodiments of all aspects of the invention will now be described with reference to the accompanying drawings, wherein: Figure 1 is a perspective view of a channel according to the invention; Figure 2 is a rear view of part of a short length of channel according to a second aspect of the invention; Figure 3 is a side view of the part shown in Figure 2; Figure 4 is a perspective view of a wall tie for use with the channel shown in Figures 1 or 2 and 3; Figures 5 and 6 are alternative embodiments of the wall tie shown in Figure 4; Figures 7(a) and (b) are front and side views respectively of a further embodiment of a wall tie for use with the channel shown in Figures 1 or 2 and 3; Figure 8(a) and (b) are front and side views respectively of an alternative embodiment of the wall tie shown in Figures 7(a) and (b); Figure 9 is a plan view of a wall tie having a flexible sleeve;; Figure 10 is a plan view of a plate for a bolt for use with the channel shown in Figures 1 or 2 and 3; Figures 11(a) and (b) are side and plan views of a bolt having a screw-threaded plate for use with the channel shown in Figures 1 or 2 and 3; Figure 12(a) shows a method of attaching an anchoring wall tie to the rear of the channel of Figure 1; Figure 12(b) is a section view along line AA of Figure 12(a) with the wall tie in position; Figure 13 shows an alternative method of attaching an anchoring wall tie to the rear of the channel of Figure 1; and Figures 14(a) and (b) show a method by which a short length of channel as shown in Figure 1 may be embedded into a concrete wall.

Figure 1 shows a channel 1 having a rear portion 2 and two arms 3. Opposing grooves 4 are formed between the arms 3 and the rear portion 2 and a gap 5 is left between the arms 3. The feet of a wall tie may be inserted into the interior of the channel 1 through the gap 5 and brought into locking engagement with the grooves 4 under the arms 3 by twisting.

British Standards states an average mortar joint thickness of 10mm. It is necessary, therefore, that the exterior depth A' of the channel 1 does not exceed 10mum.

In order to achieve a firm fixing between the grooves 4 and the feet of a wall tie lockingly engaged therewith, the interior width B of the channel 1 is a plurality of times larger than the interior depth A of the grooves 4. The ratio of interior width B of the channel 1 to interior depth A of the grooves 4 is substantially 8, but may vary between approximately 6 and 10.

The dimensions of the channel 1 are limited in this way to be suitable for the desired use.

The channel may also be easily formed into shaped portions. Holes 6 are located in the rear portion 2 at convenient intervals. These facilitate fixing of the channel 1 to a wall.

Figures 2 and 3 show part of a length 1 a of a channel similar to that shown in Figure 1.

The end la' of the length 1 a is crimped in order to close the grooves and thus exclude mortar or concrete from the interior of the channel 1 a. A hole 6 may be positioned conveniently in the crimped end 1a' for attaching to shuttering.

Parallel cuts 7 are made in the rear portion 2a of the channel la and the rear portion 2a' between the cuts 7 is deformed outwardly in order that a plate or strip (not shown) may be passed through the cuts 7 and between the rear portion 2a and the outwardly deformed rear portion 2a'. This plate or strip provides anchorage for the channel la when cast into a concrete wall.

Figure 4 shows a perspective view of a wall tie 8 for use with the channel described above. The wall tie 8 has a head portion 9 and feet 10 for locking engagement with the grooves 4. The wall tie 8 is made from a single length of shaped wire in order to provide resilience to the feet 10. The head portion 9 and the feet 10 are coplanar.

In order to insert the wall tie 8 into the channel 1 shown in Figure 1, the wall tie 8 is positioned such that the plane thereof is paraliel to the longitudinal axis of the channel 1.

The feet 10 are then inserted into the interior of the channel 1 through the gap 5 between the arms 3. The feet 10 of the wall tie 8 are then displaced towards each other and the wall tie 8 is rotated through 90 so that the feet 10 lie transversely across the channel 1 in locking engagement with the grooves 4.

The wall tie 8 may be located at any position along the channel 1. Upon release of the feet 10, the feet 10 move outwardly and the wall tie 8 is held in position in the channel 1. The position of the wall tie 8 may be altered by merely displacing the feet 10 towards each other and sliding the wall tie 8 along the channel. Thus the variation in positioning of the wall tie 8 is unlimited.

Figures 5 and 6 show alternative wall ties 8a and 8b similar to that shown in Figure 4.

Each wall tie 8a, 8b has a head portion 9 and feet 10a, 10b. The wall tie 8a shown in Figure 5 has feet 10a having protrusions 10a' arranged perpendicular to the plane of the head portion 9. These protrusions 10a' allow twisting of the waiF tie 8a in the channel in one direction only and once fitted the tie is prevented from sliding along the channel by a combination of spring loading of the feet 10a against the interior surface of the grooves of the channel and a cam action which occurs between the protrusions 10a' and the base of the grooves. To adjust these ties, the tie legs are pressed together thereby releasing the locking action. Rotation is prevented in all three planes by this arrangement which thus provides a very firm fixing of the wall tie 8a in the channel.

The wall tie 8b shown in Figure 6 is substantially the same as that shown in Figure 4; however, the feet 10b are arranged perpendicular to the plane of the head portion 9. Thus, when the wall tie 8b is in locking engagement with the channel, the head portion 9 is parallel to the longitudinal axis of the channel.

All of the above described wall ties are made of shaped wire. The diameter C of the wire is substantially the same, but not greater than, the interior depth A of the grooves 4 (see Figure 1). This increases the firmness of the fixing of the wall tie 8, 8a, 8b in the channel.

A wall tie 11 formed from rigid metal sheet is shown in Figures 7(a) and (b). A substantially flat tongue 12 is divided at one end 12' by a longitudinal notch 13 in order to improve fixing of the wall tie 11 to the new wall. The opposite end 12" is shaped into a foot 14 perpendicular to the plane of the tongue 12.

Indentations 15 are provided adjacent the foot on either side of the tongue 12. The wall tie 11 may be inserted into a channel as shown in Figure 1 by positioning the plane of the tongue 12 parallel to the longitudinal axis of the channel 1 and inserting the foot 14 into one groove 4 via the gap 5 (see Figure 1).

The wall tie 12 is then twisted so as to bring the indentations 15 into locking engagement with the arms 3 and the foot 14 into locking engagement with both grooves 4. The wall tie 11 is slidable in the channel 1 and therefore unlimitedly variable in position therealong.

A deformation 16 may be manufactured into the wall tie 11 in order to prevent the transference of moisture between the outer and inner leaf of a cavity wall construction. Alternatively this may be a 90 or 180 degree twist in the body of the wall tie or any other shape to prevent the transference of moisture.

A variation of the wall tie 11 is shown in Figures 8(a) and (b). The wall tie 1 1s has a tongue 12a divided by a notch 13a at one end 12a'. The feet 14a are formed in this case by the dividing and opposed shaping of the end 12a" of the tongue 12a.

Figure 9 shows a simple wall tie 1 7 having a substantially rectangular tongue 18 and a loose fitting sleeve 19. Indentations 15b are provided adjacent feet 14b at one end 18' of the tongue 18. The wall tie 17 may be inserted into a channel as shown in Figure 1 by inserting the feet 14b into the interior of the channel 1 through the gap 5 and twisting in order to bring the identations 15b and the feet 14b into locking engagement with the arms 3 and the grooves 4 respectively. The wall tie 17 may be embedded into a mortar joint such that only the sleeve 19 is in contact with the mortar, thus allowing relative displacement in the plane of the sleeve between the tongue 18 and the new wall.

Figure 10 shows a plate 20 for use with a bolt or stud (not shown) and a channel as shown in Figure 1. The plate 20 has an aperture 21 for receiving a bolt or stud and a raised portion 22. The plate may be inserted into the channel 1 through the gap 5 between the arms 3 and twisted to bring the plate 20 into locking engagement with the grooves 4 (see Figure 1). The raised portion 22 is shaped as shown in order that twisting in one direction only is permitted. The plate 20 may have a recess (not shown) for accommodating the head of a bolt.

Figures 11 (a) and (b) show an alternative plate 23 with a threaded bolt or stud 24. The plate 23 has a substantially parallelogrammic shape and has an aperture (not shown) having a screw thread wherein the bolt or stud 24 is received. The plate may be recessed in order to accommodate the head of a bolt 24. The plate is inserted into the channel through the gap 5 and twisted to bring the plate 23 and groove 4 into locking engagement (see Figure 1). The plate 23 is slidable in the channel.

The bolt or stud 24 may then be displaced relative to the plate 23 such that the bolt head or stud end is brought into contact with the rear portion 2 of the channel 1 whilst the plate 23 is brought into contact with the interior surface of the arms 3. The plate 23 is held in position in the channel 1 in this way.

It should be noted that any fitting which is suitable for use with the channel shown in Figure 1 is also suitable for use with that shown in Figures 2 and 3.

Figures 12 to 14 show methods of attaching a length of channel to a concrete wall. In Figure 12(a) the rear portion 2b of a length of channel 1 b has two colinear outwardly deformed portions 2b'. The outwardly deformed portions 2b' are shaped so as to recieve the feet 10 of a wall tie 8 described above and shown in Figure 4. In order to insert the feet 10 into the deformed portions 2b', the resiliently sprung feet 10 are pressed together in the direction of the arrows 26 and brought into colinearity with the deformed portions 2b'. Upon release of the feet 10 the resilience thereof causes the feet 10 to engage with the deformed portions 2b' in the manner shown in Figure 12(b). A spacer member 27 may be forced between the legs 28 of the wall tie 8 in order to prevent unwanted disengagement or rotation.The tie may then be embedded into the mortar or concrete of a wall to which the channel is thereby attached.

An alternative method of attaching a wall tie 8 to a channel 1c is shown in Figure 13. A slot 2c' is provided in the rear portion 2c of the channel 1 C. If the slot 2c' is provided adjacent an end 1 c, of a length of channel 1-c the slot may engage with the end 1 c' as shown. The wall tie 8 is inserted into the slot 2c' by pressing the resiliently sprung feet 10 of the wall tie 8 together and passing them through the slot 2c' into the grooves 4c of the channel lc. On release of the feet 10 the wall tie 8 is brought into locking engagement with the channel 1 C and may be embedded into the mortar or concrete of a wall to which the channel is thereby attached.A plug 29 may be inserted into the end 1c' of the channel 1 C when the slot is adjacent thereto; this is a precaution against inadvertant disengagement and an excluder to mortar and concrete.

Figure 14 shows a method for embedding a short length of the channel 1 as shown in Figure 1 into a concrete wall. Two ties 30 are provided, each having a head section 31 shaped to fit into the grooves 4 of the channel 1 in tne direction of arrows 32. Each tie 30 has two legs 33 extending perpendicularly from the head section 31. The legs 33 are grooved or roughened to increase adhesion with mortar or concrete. The head sections 31 of the ties 30 are inserted into the ends 1',1" of the channel 1, the length of which corresponds to the height of a block 34 of the wall to which the channel is to be attached. The legs 33 are embedded into mortar or concrete above and below, or either side of, the block 34 as shown in Figure 14(b).

The above described channel and fittings provide a method of tying a new wall to an existing, new, or previously constructed wall in cavity and non-cavity conditions with no restriction as to size of brick or block since the positioning of the ties is unlimitedly variable.

Claims

1. A channel for holding a wall tie in locking engagement having a rear portion and two arms spaced from the rear portion to form opposed grooves, wherein the interior width of the rear portion is a plurality of times larger than the interior depth of the grooves, so that a wall tie may be inserted into the channel between the arms and held on twisting in any desired position by locking engagement with the grooves.

2. A channel as claimed in Claim 1, wherein the exterior depth of the channel does not exceed lOmm.

3. A channel as claimed in Claim 1 or 2, wherein the ratio of the interior width of the rear portion to interior depth of the grooves is between 6 and 10.

4. A channel as claimed in any one of Claims 1 to 3, wherein the ratio of the interior width of the rear portion to interior depth of the grooves is substantially 8.

5. A channel as claimed in any one of Claims 1 to 4, wherein the rear portion comprises holes for receiving screws, whereby the channel may be attached to a wall.

6. A channel as claimed in any one of the preceding Claims, wherein the rear portion has means for accommodating an elongated plate to provide anchorage for the channel.

7. A channel as claimed in Claim 6, wherein the means for accommodating the elongated plate comprise two cuts in the rear portion, the rear portion between the two cuts being deformed outwardly.

8. A channel as claimed in any one of Claims 1 to 5, wherein the rear portion has means for accommodating a wire tie to provide anchorage for the channel.

9. A channel as claimed in Claim 8, wherein the means for accommodating a wire tie comprise two colinear outwardly deformed portions for receiving the feet of the wire tie.

10. A channel as claimed in Claim 8, wherein the means for accommodating a wire tie comprise a slot arranged transversely to the longitudinal axis of the channel.

11. A channel as claimed in any one of the preceding Claims, having crimped ends so as to exclude mortar or concrete from the channel interior.

12. A fitting for use with a channel as claimed in any one of Claims 1 to 5, having a head portion insertable into the grooves of the channel from the end thereof and grooved legs extending perpendicularly to the head portion.

13. A fitting for use with a channel as claimed in any one of Claims 1 to 11, having holding means whereby the fitting may be inserted into the channel between the arms and brought into locking engagement in the grooves by twisting of the fitting relative to the channel.

14. A fitting as claimed in Claim 13, wherein the fitting is a wall tie having a head portion and resiliently sprung feet forming the holding means.

15. A fitting as claimed in Claim 14, wherein the head portion and feet are coplanar.

16. A fitting as claimed in Claim 14, wherein the feet are coplanar and substantially perpendicular to the head portion.

17. A fitting as claimed in any one of claims 14 to 16, formed from a single shaped length of wire.

18. A fitting as claimed in Claim 17.

wherein the diameter of the wire is substantially the same as the interior depth of the grooves.

19. A fitting as claimed in Claim 17 or 18, wherein the diameter of the wire does not exceed 5mm.

20. A fitting as claimed in Claim 13, wherein the fitting is a wall tie having a substantially flat tongue and shaped feet forming the holding means.

21. A fitting as claimed in Claim 20, wherein the tongue is partially divided by means of a longitudinal notch to facilitate fixing of the fitting within a mortar joint.

22. A fitting as claimed in Claim 20 or 21, wherein the holding means comprise indentations for locking engagement with the arms of the channel.

23. A fitting as claimed in Claim 20, further comprising a sleeve for arrangement around the tongue so as to allow relative movement between the tongue and the sleeve.

24. A fitting as claimed in Claim 13, comprising a bolt or stud and a plate having an aperture for receiving the bolt or stud, the plate forming the holding means.

25. A fitting as claimed in Claim 24, wherein the bolt or stud and aperture are screw-threaded such that displacement of the bolt or stud relative to the plate provides means for preventing sliding movement of the fitting in the channel.

26. A channel substantially as herein described with reference to Figures 1 or 2 and 3 of the accompanying drawings.

27. A wall tie substantially as herein described with reference to any one of Figures 4 to 9 of the accompanying drawings.

28. A fitting substantially as herein described with reference to Figure 10 or 11 of the accompanying drawings.

29. A method of tying a new wall to an existing, new or previously constructed wall comprising the steps of fixing a channel as claimed in any one of Claims 1 to 10 and 26 to the existing wall, inserting at least one wall tie as claimed in any one of claims 14 to 23 and 27 into the channel in a lockingly engageable, unlimitedly adjustable manner, and embedding the head portion of the at least one wall tie into the mortar joint of the new wall.

30. A method as claimed in Claim 29, wherein the channel is embedded in a mortar joint between the two walls.

31. A method as claimed in Claim 29 or 30, wherein the new wall is formed of bricks and a wall tie is embedded into every fifth mortar joint thereof.

32. A method as claimed in any one of Claims 29 to 31, wherein the channel is fixed to the existing wall by means of screws.

33. A method as claimed in any one of Claims 29 to 32, wherein a channel as claimed in Claim 7 or 8 is anchored to the existing, new or previously constructed wall by embedding the elongated plate or wire tie in mortar applied thereto or casting the same into concrete.

34. A method as claimed in any one of Claims 29 to 32, wherein a channel as claimed in Claim 9 or 10 is anchored to the existing, new or previously constructed wall by embedding the wire tie in mortar applied thereto or casting the same into concrete.

35. A method as claimed in any one of Claims 29 to 34, wherein the channel has crimped ends so as to exclude mortar or concrete from the channel interior.

36. A method as claimed in any one of Claims 29 to 32, wherein a fitting as claimed in Claim 12 is inserted into each end of the channel and the legs of the fitting are embedded into mortar or concrete of existing, new, or previously constructed walls.

37. A method substantially as herein described with reference to the accompanying drawings.