GB2318597A

GB2318597A - Wall tie

Info

Publication number: GB2318597A
Application number: GB9722391A
Authority: GB
Inventors: Graham Law
Original assignee: Ancon Clark Ltd
Current assignee: Ancon Clark Ltd
Priority date: 1996-10-25
Filing date: 1997-10-24
Publication date: 1998-04-29
Anticipated expiration: 2017-10-24
Also published as: GB9622233D0; GB2318597B; GB9722391D0

Abstract

A wall tie for use in cavity wall construction, is capable of accommodating vertical and horizontal relative movement of the leaves of the wall in the plane of the wall, while preventing relative movement perpendicular to the plane of the wall. The wall tie comprises a first part (1) anchored to the first leaf and a second part (11) anchored to the second leaf. The first part has an elongate dowel portion (8) which engages in one or more elongate slots (16,17) in the second part. The dowel and slot connection accommodates movement by sliding along the slot in a direction perpendicular to the dowel and moving through the slot in a direction parallel to the dowel.

Description

TWO PART TIE This invention relates to wall ties.

Wall ties are used in the construction industry to confer structural stability and rigidity to walls made of brick, stone, masonry and other forms of cladding and construction materials. One common form of wall construction is the cavity wall, in which outer and inner leaves are separated by a gap. The outer leaf, which is generally exposed to the elements, is normally made from an environmentally resistant material such as brick or stone. The inner leaf may be made of similar materials, but quite commonly can be made of less durable materials such as breeze block, plasterboard and composite constructions.

Wall ties can be of several designs, the simplest of which comprise steel rods or bars with one end anchored to one leaf and the other end anchored to the other leaf. The anchoring means is suited to the leaf construction material; for brick, stone or other block construction, the wall ties are anchored at their ends in the layer of mortar used to bind the brick, stone or blocks together.

Other more complex wall ties include versions with one end region adapted to fit into, and be secured in a channel cast into a concrete wall or column. Wall ties of this type are more commonly used where one leaf of a cavity wall is constructed in advance of the other leaf which may lead to coursing problems.

The present invention provides a wall tie having end regions capable of being anchored to respective sides of a cavity wall construction, wherein the end regions are capable of movement relative to each other in at least two planes.

In one embodiment of the present invention the wall tie comprises first and second parts attached such they can move relative to each other in at least two planes.

The two parts can be separate pieces or can form separate parts of a unitary tie.

The first part of the wall tie can comprise a body which, in use, is horizontal, and has at one end, the end region capable of being anchored to the wall. At its other end, the body can have a head which, in use, is generally in a different plane (preferably vertical) and can cooperate with slots on the second part.

Preferably the body of the first part is arranged perpendicular to the head, although other angles can be adopted.

The head may in the form of a bar.

Preferably the body has a drip former, most preferably close to the middle of the body.

The second part of the wall tie can be C- or U-shaped with slotted arm portions and means to allow attachment of the second part to a region of the cavity wall.

Preferably the means of attachment comprise holes which allow the second part to be screwed or bolted to a region of the cavity wall.

In another embodiment of the present invention there is provided a second part of the wall tie which is C- or U-shaped with slots in the arm portions and means to allow attachment of the second part to a region of the cavity wall.

Preferably the attachment means is a strip of metal which can be embedded at one end in a layer of mortar used to bind the construction materials together.

The wall tie can be constructed from metal, plastic or any suitable material.

Preferably the metal is ferrous.

Preferably the metal is steel.

Preferably the steel is stainless steel.

The wall tie of this invention offers advantages over the prior art in that it allows for the movement of the leaves of a cavity wall in two planes, but can restrain movement of the two leaves away from one another.

These wall ties are relatively simple to attach to the leaves of a cavity wall.

The invention will now be further described without limitation by reference to the following examples and figures: Figure 1: illustrates the first embodiment of the wall tie according to the present invention.

Figure 2: illustrates a further embodiment of the wall tie according to the present invention.

Figure 3a: illustrates a side view of the first embodiment of the wall tie.

Figure 3b: illustrates a plan view of the first embodiment of the wall tie.

Figure 4: illustrates a view looking along the longest axis from the C- or U-shaped part of the first embodiment of the wall tie.

Figure 5: illustrates a side view of movement of the leaves of a cavity wall, wherein the leaves are connected by the second embodiment of the wall tie.

Figure 6: illustrates a plan view of horizontal movement of the leaves of a cavity wall, wherein the leaves are connected by the second embodiment of the wall tie.

A wall tie (see Figure 1) comprises a first part 1 having an elongate body 2 which is generally rectangular in shape. One end 3 of the body 2 is generally ovoid in shape and is provided with a hole 4 for anchoring the end in mortar. Alternatively, fishtail ends can be used. The body 2 is provided with drip former 5, which is positioned across a middle portion. The drip former is generally V-shaped with the apex of the V-shape pointing downwards in use of the tie.

The other end 6 of the body 2 has a head in the form of a rod or dowel 8 passing through a hole in the end 6 and welded or glued therein. The rod 8 is fixed perpendicular to the plane of the body 2, such that the opposite ends 9 and 10 of the rod 8 are disposed respectively above and below the plane of the body 2.

The rod 8 can also be fixed at other angles relative to the plane of the body 2. The rod is typically 80 to 100 mm long and may be manufactured from 8 mm diameter rod.

The second part 11 of the tie is generally C- or Ushaped having a base 12 and two arms 13 and 14. It can be manufactured by cutting a short length (typically 60 to 100mm) from a longer length of channel material.

The base 12 can be provided with one or more holes 15 which allow the second part 11 to be attached to a leaf of a wall by a bolt or a screw or other suitable fixing means.

The arms 13 and 14 are provided with parallel slots 16 and 17 in alignment with one another along the arms.

These slots 16,17 can receive the ends of the rod 8 allowing the first and second parts 2 and 11 to move relative to each other in two planes i.e. vertical and horizontal. The slots are nominally wider than the diameter of the rod, to allow free sliding passage of the rod within the slot. If an 8 mm diameter rod is used then the slot will be typically 9 mm wide. The horizontal movement is perpendicular to the length of the body 2. The slots 16,17 prevent the rod from moving away from the second part, and thus extension of the tie is prevented also. The slots 16, 17 are typically 50mm long to allow +/- 20mm movement in the direction of Arrow A. The arms 13, 14 are typically 45 mm apart to allow +/- 20mm movement in the direction of Arrow B. If greater movement must be accommodated then the length of the rod 8, the spacing of the arms 13, 14 and the length of the slots 16, 17 may be increased accordingly.

In a further embodiment of this invention shown in Figure 2, the second part 11 of the wall tie has an elongate body 18 extending from the base portion 12.

The body 18 is generally similar to the body 2 being generally rectangular with an ovoid end 19 provided with a hole 20. The end 19 is suitable for embedding in a layer of mortar to anchor the body 18 (and the second part 11) to a leaf of a wall. The bodies 2 and 18 can be coplanar in use, or in some other arrangement ie; arranged at an angle to one another in the assembled tie.

The rod 8 is shown located centrally with a slot 16 in arm 17 of the second part 11 of the wall tie.

The spacing between the arms 13 and 14 of the second part 11 allows the vertical movement of the body 2 relative to the second part 11 without the end(s) 10 of the rod 8 leaving the slot(s) 17.

The first and second parts 1, 11 can move horizontally relative to each other by virtue of the bar 8 being moveable along the slots 17 and 18.

The horizontal and vertical movements of the first and second parts 1, 11 are possible simultaneously or singularly without prejudicing the ability of the wall tie to maintain two leaves 21 and 22 of a wall at a set distance apart.

Figure 4 illustrates a view looking along the longest axis of the wall-tie from the second part 11. This clearly shows the diametrically opposite positions of the holes 15, for attaching the wall-tie 1 to a leaf of a wall.

Figure 5 shows a side view of the wall-tie, showing vertical displacement in the direction of Arrow B of two leaves 21 and 22 attached to opposite ends of the wall-tie. The first 1 and second 11 parts of the walltie are attached to the leaves 21 and 22 respectively by embedding the ends 3 and 19 of elongate sections 2 and 18 in mortar 23 between building block materials, e.g. blocks, stone or any other suitable construction material.

The horizontal displacement of two leaves 21 and 22 attached to opposite ends 3 and 19 of the wall-tie is clearly shown in Figure 6. The horizontal displacement is in the direction of arrow A, i.e. normal to the length of elongate section 2.

The wall tie of the invention is particularly useful in preventing or ameliorating the problems associated with rigid ties, namely that settlement of one leaf of a wall can distort the other leaf tied thereto with rigid ties. The invention nevertheless allows the production of a wall tie which restrains movement of the two leaves away from each other. The invention also allows easier construction of a cavity wall, since the mortar beds of the two leaves need not be precisely aligned during construction.

The wall tie of the invention is especially useful for tying walls comprising large panels of brickwork or other construction materials, where the effects of thermal expansion of the panel(s) causes considerable differential movement between the two leaves of the wall. This can be a particular problem with large panels of brickwork, where the outer skin is of clay brickwork and the inner skin is of concrete blockwork.

Modifications and improvements can be incorporated without departing from the scope of the invention.

Claims

1. A wall tie comprising first and second parts capable of being anchored to respective sides of a cavity wall construction, said first and second parts being attached to each other such they can move.

relative to each other in two mutually perpendicular directions but are restrained from relative movement in a third direction perpendicular to the plane of the cavity wall.

2. A wall tie according to Claim 1, wherein the second part of the wall tie comprises a body portion and attachment means for attachment to the wall, the body portion being provided with one or more elongate slots.

3. A wall tie according to Claim 2, wherein the body portion of the second part comprises two spaced apart flange portions, each provided with an elongate slot.

4. A wall tie according to Claims 2 or 3, wherein the attachment means comprise holes which allow the second part to be screwed or bolted to a region of the cavity wall.

5. A wall tie according to Claims 2 or 3, wherein the attachment means comprises an anchor portion adapted to be embedded in the mortar of a wall.

6. A wall tie according to any of Claims 2 to 5, wherein the first part of the wall tie comprises a body portion which, in use, is horizontal, and has at a first end an anchor portion capable of being anchored to the wall, and at its other end a head portion capable of cooperation with said slot or slots in the second part.

7. A wall tie according to Claim 6, wherein the head portion comprises an elongate member extending, in use, through said slot or slots of the second part, and extending in a direction parallel to the plane of the wall and perpendicular to the slots.

8. A wall tie according to Claims 3 and 7, wherein said elongate member is attached to the body portion of said first part, such that, in use, the body portion of said first part extends between the flange portions of said second part, and such that the first and second ends of said elongate member extend through the slots in the first and second flange portions respectively.

9. A wall tie according to any one of Claims 6 to 8, wherein the body portion of the first part is elongate and provided with a drip former.

10. A wall tie according to any preceding Claim wherein the wall tie is constructed from metal or plastic.

11. A wall tie according Claim 9, wherein the wall tie is constructed from steel or stainless steel.

12. A wall tie anchoring device, comprising capable of being anchored to a leaf of a cavity wall construction, comprising a body portion and attachment means for attachment to the leaf, the body portion comprising two opposing, spaced apart flange portions, each provided with an elongate slot.

13. A wall tie anchoring device according to Claim 12, wherein the body portion comprises a U- or C-shaped channel section.

14. A wall tie as hereinbefore described with reference to the accompanying drawings.