GB2212835A

GB2212835A - Cavity wall tie

Info

Publication number: GB2212835A
Application number: GB8827752A
Authority: GB
Inventors: Mark John Tetsell
Original assignee: UNIVERSAL PANELS
Current assignee: UNIVERSAL PANELS
Priority date: 1987-11-27
Filing date: 1988-11-28
Publication date: 1989-08-02
Anticipated expiration: 2008-11-28
Also published as: GB8827752D0; GB2212835B

Abstract

A cavity wall tie comprising a bracket to be fixed to the face adjacent the cavity of one of the skins of the wail after that skin has been erected, or at least partly built, the bracket having at least one flange 12 thereon which, when the bracket has been fixed in a required position, projects from said one skin into the cavity and is substantially upright, the flange 12, or each flange 12, having a slot 14 therein extending lengthwise of the flange, that is substantially upright when the bracket has been fixed in position. The wail tie also comprises a link 13 having a portion 15 thereof extending transversely through the slot or slots 14 with freedom to enable the link 13 to be slid upwardly and downwardly with respect to the bracket and for the link 13 to be swung with respect to the bracket to extend across the cavity. <IMAGE>

Description

CAVITY WALL TIE The invention relates to a cavity wall tie for connecting the two skins of a cavity wall of a building together.

According to the invention, the cavity wall tie comprises a bracket to be fixed to the face adjacent the cavity of one of the skins of the wall after said one skin has been erected, or at least partly built, the bracket having at least one flange thereon which, when the bracket has been fixed in a required position, projects from said one skin into the cavity and is substantially upright, the or each flange having a slot extending lengthwise of the flange, that is substantially upright when the bracket has been fixed in position, the wall tie also comprising a link having a portion thereof extending transversely through the slot with freedon to enable the link to be slid upwardly and downwardly with respect to the bracket and for the link to be swung with respect to the bracket to extend from the bracket across the cavity to enable an end portion of the link remote from the bracket to be secured to the other skin of the wall by being held between two brick, block or other courses from which said other skin is built.

Conveniently the bracket is of channel shape and has a base which enables the bracket to be fixed against said one skin of the wall and two side flanges each having a slot therein, the slots being aligned one with the other transversely of the bracket and the link having a transverse portion which bridges across the two side flanges and is freely slidable along the slots thereof and which enables the link to be swung with respect to the bracket to extend from the bracket across the cavity to said other skin of the wall.

The link may be made from stiff wire bent to form a loop of substantially rectangular or trapezium shape having one end portion defining said transverse portion, an opposite substantially parallel end portion which is to be held in said other skin of the wall and two side portions extending between the bracket and said other skin of the wall. The said opposite end portion may have a permanent gap therein to enable the link to be attached to or removed from the bracket by passing an end of the wire through the slots or the wire may have two ends which are closed together after attachment of the link to the bracket and which are then secured together.

The two side portions of the link may be kinked to impart rigidity to the link. Where the link is of trapezium shape, the shorter of the two substantially parallel end portions is located in the slots of the bracket and the longer of the two substantially parallel end portions formed by the two ends of the wire link is held between courses of said other skin of the wall.

Thus the two side portions diverge across the cavity from the bracket to said other skin, thereby to result in an assembled tie which will withstand a high tensile load.

The bracket and the link are conveniently made of metal or other rigid material to comply with recommended standards or bye-laws applying to cavity wall ties, especially with regard to the ultimate tensile stress the ties can withstand and with regard to resistance to corrosion. The bracket and the link may each be made of a stainless steel and in that case need not have a protective coating, as is usual for cavity wall ties.

By way of example, a cavity wall tie in accordance with the invention is now described with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a first embodiment of the wall tie, Figure 2 is a diagram showing wall ties of the kind shown in Figure 1 in a cavity wall construction, and Figure 3 is a perspective view of a second embodiment of the wall tie.

Referring to Figure 1, the wall tie comprises two parts.

One part is a channel-shaped bracket having a base 1 and two parallel sides 2 and the other is a substantially rectangular link of stiff wire 3. Each side 2 of the bracket where it joins the base 1 has a closed slot 4 therein extending longitudinally of the bracket. The link 3 has one end portion 5 which extends through both slots 4, which are aligned one with the other transversely of the bracket, an opposite end portion 6 which has a gap 7 therein to enable one end of the bent wire link to be passed through the slots 4 and two side portions 8 which are each kinked at 9 to impart rigidity to the link. The link 3 is slidable freely up and down the slots 4 and is also free to be swung upwardly and downwardly with respect to the bracket. Instead of providing the gap 7, the ends of the wire may be closed together after assembly and may then be permanently secured.The bracket and the link may be made of materials suitable for wall ties in that they comply with recommended standards or bye-laws, especially with regard to strength (ultimate tensile stress) and resistance to corrosion. For example both the bracket and the link may be made of stainless steel and therefore need not be coated, as has been a requirement hitherto for cavity wall ties.

In use, a plurality of wall ties are positioned at required intervals in the width and height of a cavity wall by fixing, e.g., by screwing, the brackets in substantially upright positions to an erected or at least partly built inner skin 10 of a cavity wall construction.

The inner skin may be of any suitable construction, for example, boards or panels, as shown, or building blocks or bricks. The outer skin 11 is built from courses of building blocks or bricks. When a course of the outer skin level with a tie is reached, the link thereof is swung outwardly with respect to the bracket and rested on top of the course and then a block or brick of the next course is laid on top of the outer end portion 6 of the link and is secured by mortar in known manner.

As the link is freely slidable with respect to the slots 4 upwardly and downwardly of the bracket, adjustment in height of the link appropriate for the height of the course on which the outer end portion 6 of the link is laid can readily be effected. Also cavities of different width or variation of width of a cavity can be accommodated by the angle of swinging of the link or by its depth of penetration into the outer skin.

Figure 3 shows the second embodiment of the wall tie which is similar to Figure 1 except that slots 14 are formed wholly in the sides 12 of the bracket and the link 13 is of trapezium shape in which the end portion 15, which extends through the slot 14, is shorter than the parallel end portions 16 which is to be embedded in mortar between two courses of the outer skin of the wall. Thus the side portions 18 of the link 13 diverge across the cavity between the shorter end portion 15 towards the'longer end portions 16. This construction reduces any tendency for the embedded end portions 16 to be pulled out of the mortar and results in a tie 13 which can withstand a high tensile load between the embedded end portions 16 and the bracket. The end portions 16 may be closed together before they are embedded in mortar or may have a permanent gap 17 therebetween. As in the first embodiment, the side portion 18 of the link may be kinked at 19.

In some wall constructions, the bracket may be fixed to the outer skin and the end of the link remote from the bracket may be built into the courses of the inner skin.

Claims

1. A cavity wall tie comprising a bracket to be fixed to the face adjacent the cavity of one of the skins of the wall after said one skin has been erected, or at least partly built, the bracket having at least one flange thereon which, when the bracket has been fixed in a required position, projects from said one skin into the cavity and is substantially upright, the or each flange having a slot extending lengthwise of the flange, that is substantially upright when the bracket has been fixed in position, the wall tie also comprising a link having a portion thereof extending transversely through the slot with freedom to enable the link to be slid upwardly and downwardly with respect to the bracket and for the link to be swung with respect to the bracket to extend from the bracket across the cavity to enable an end portion of the link remote from the bracket to be secured to the other skin of the wall by being held between two brick, block or other courses from which said other skin is built.

2. A cavity wall tie as claimed in Claim 1 in which the bracket is of channel shape and has a base which enables the bracket to be fixed against said one skin of the wall and two side flanges each having a slot therein, the slots being aligned one with the other transversely of the bracket and the link having a transverse portion which bridges across the two side flanges and is freely slidable along the slots thereof and which enables the link to be swung with respect to the bracket to extend from the bracket across the cavity to said other skin of the wall.

3. A cavity wall tie in which the link is made from stiff wire bent to form a loop of substantially rectangular or trapezium shape having one end portion defining said transverse portion, an opposite substantially parallel end portion which is to be held in said other skin of the wall and two side portions extending between the bracket and said other skin of the wall.

4. A cavity wall tie as claimed in Claim 3 in which said opposite end portion has a permanent gap therein to enable the link to be attached to or be removed from the bracket by passing an end of the wire through the slots.

5. A cavity wall tie as claimed in Claim 3 in which said opposite end portion has a pair of ends which are closed together after attachment of the link to the bracket and which are then secured together.

6. A cavity wall tie as claimed in any of Claims 3 to 5 in which the link is of trapezium shape and in which the shorter of the two substantially parallel end portions is located in the slots of the bracket and the longer of the two substantially parallel end portions formed by the two ends of the wire link is held between courses of said other skin of the wall.

7. A cavity wall tie as claimed in any of Claims 3 to 6 in which the two side portions of the link are kinked to impart rigidity to the link.

8. A cavity wall tie as claimed in any preceding claim in which the bracket and the link are made of metal or other rigid material.

9. A cavity wall tie as claimed in Claim 8 in which the bracket and the link are made of stainless steel.

10. A cavity wall tie constructed and arranged substantially as described herein with reference to Figures 1 and 2 or Figure 3 of the accompanying drawings.