GB2234763A

GB2234763A - Wall tie

Info

Publication number: GB2234763A
Application number: GB8917326A
Authority: GB
Inventors: Ronald Charles Sammons
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-07-28
Filing date: 1989-07-28
Publication date: 1991-02-13
Also published as: GB8917326D0

Abstract

A tie for securing a new to an existing wall is in two parts to allow some relative vertical movement in the event of settlement of the new wall. A first part secured to the existing wall is a plate 1 having vertical slots 4 which slidably capture the headed-end 7 of a wall tie. The headed-end 7 may be a T-section engaged in the slots 4 by rotating through 90 DEG , or they may enter an enlarged section of the slots. <IMAGE>

Description

WALL TIES This invention relates to wall ties and their method of manufacture.

When creating new buildings or altering existing buildings it is frequently necessary to build a new wall of bricks or blocks on to an existing wall. It is good building practice, and a requirement under the current United Kingdom Building Regulations, to ensure that the new wall is tied to the existing wall. To facilitate attachment of the new wall to an existing wall various pre-fabricated wall tie devices have been proposed. Some of these devices also assist in the vertical alignment of the bricks or blocks forming the new wall. Such devices are described in GB-A-2 162 216 and GB-A-2 162 217.

The above devices tie two walls together rigidly so that vertical movement of the new wall with respect to the old wall is not possible. In the event that the new wall is built on uncompacted soil subsidence can only be accomodated by cracking, usually along the mortar filling the courses between the bricks or blocks. It has been proposed in GB-A-2 206 139 that a new wall be attached to an existing wall in a manner which allows it to move vertically. The new wall carries tying means between the courses of bricks or blocks which engage a vertical member attached to the existing wall. Limited vertical movement is provided through the ends of the tying means being adapted to slide in a strap on the vertical member. The range of vertical movement provided by such a device is limited and extensive movement will cause the tying means to leave the strap.This effectively destroys the attachment between the two walls with the possibility of collapse.

According to the present invention there is provided apparatus for tying a first, existing, wall to a second, new, wall comprising a vertical member adapted to be rigidly attached to the first wall and tying member adapted to be retained within the structure of the second wall and having engagement means for connection with the vertical member, characterised in that, the vertical member carries vertically oriented slots and the tying member is adapted to slidably engage the slot prior to retention in the second wall.

The vertical member consists of a strip of metal pierced with fixing holes so that it can be rigidly attached to an existing wall along the vertical line where the new wall will be constructed. The edges of the strip may be folded or bent to improve rigidity and, preferably, to provide guides for the bricks or blocks forming the new wall.

Ridges may be pressed into the surface of the vertical member to improve rigidity.

The vertical member carries a series of vertically oriented slots which are adapted to receive the ends of tying members. Once engaged in the slots the tying members are free to move in a vertical direction the full length of the slot. Slots from 60 to 100 mm may be used according to the distance between courses and the amount of subsidence which must be accomodated.

In one embodiment the ends of the tying members are 'T' shaped and after inserting the head of the 'T' into the slot are rotated through a right angle. The 'T' shaped end of the tying member is then free to move up and down the slot while being retained by the arms of the 'T' shaped head.

In an alternative embodiment the tying member carries a flat circular head at one end having a diameter greater than that of the width of the vertical slot. Each slot comprises a main vertical slot portion which is continued at either or both ends through an angle of at least 90 degrees or, most preferably, through 180 degrees to end in a circular aperture. The circular aperture has a diameter slightly larger than that of the head of the tying member.

In use the head of the tying member is inserted into the aperture and the member is directed along the slot until the vertical portion is reached. In a most preferred embodiment the slots are in the form of an 'S' having a straight central portion with both ends terminating in a circular aperture.

In both embodiments it is preferred that the portion of the vertical member carrying the slot is pressed outwardly by at least the thickness of the head of the tying member.

The width of the pressed portion should be at least the width of the head of the tying member. When fixed to a wall the pressed portion forms a small gap between the surface of the wall to facilitate vertical movement of the head of the tying member.

The tying member has a head portion, as described previously, which can be inserted into the slot in the vertical member and retained. The other end of the tying member is adapted to lie within the mortar between courses of bricks or blocks and retained when the mortar has set. For this reason the end may be bent into an 'S' shape, flattened or otherwise formed, in known manner, to ensure that it is firmly retained in when the mortar is set.

The vertical member and tying members are preferably fabricated from galvanised or stainless steel.

In order that the invention may be clearly understood it will now be described with reference to the accompanying drawings in which, Figure 1 is a plan view of one form of the vertical member portion of the wall tying apparatus according to the invention, Figure 2 is a plan view of a tying member for use with the vertical member shown in Figure 1, Figure 3 is a plan view of an alternative tying member for use with the vertical member shown in Figure 1, Figure 4 is a cross-sectional view of two walls attached by tying apparatus according to the invention, Figure 5 is a plan view of an alternative form of the vertical member, Figure 6 is a plan view of a tying member for use with the vertical member shown in Figure 5.

Apparatus for tying a first, existing, wall to a second, new, wall, see Figure 1, consists of a vertical member 1 adapted to be rigidly secured to a wall or other surface by means of screws or bolts through fixing holes 2. To increase rigidity vertical bumps 3 are pressed into the member 1. The vertical member 1 carries two rows of vertically oriented slots 4. The slots 4 in each row are displaced from each other vertically so that there is at least one slot available along the whole length of the vertical member 1. The portion or the member 1 adjacent to each slot 4 is pressed outwardly around each slot as shown by portions 5.

The tying member, see Figure 2, has a 'T' shaped head portion 7 attached to an 'S' shaped end portion 8 by a shaft 9. In use the head portion 7 is inserted into the vertical slot 4 and rotated through a right angle. The 'T' shaped portion 7 is then free to move up and down the slot 4 while being retained by the arms of its 'T' shaped head. The width of the outwardly pressed portion 5 is slightly greater than the width of the 'T' of the head portion 7. Preferably the vertical member 1 is attached to the first wall before the tying member is fitted.

Tying members can be fitted to the vertical member as each course is laid and moved along the slot until the anchor portion of the tying member lies on the surface of the uppermost course of blocks or bricks.

An alternative form of the tying member, see Figure 3, is formed from a single piece of wire. The ends 11 and 12 of a length of stiff wire are each bent into a right angle so as to form a 'T'. The wires are secured together by a twisted portion 13 and then formed into a loop 14. The diameter of the wire used to form the tying member should preferably be half the width of the slot 4 in the vertical member so that it can move freely along the slot. Alternatively the pair of wires before the twisted portion 13 may be flattened to the width of the slot 4. To ensure that the tying member is firmly retained in the mortar between courses of bricks or blocks the loop 14 may be twisted so as to form a figure '8' shape.

In use, see Figure 4, the vertical member 21 is attached to a wall 22 by means of screws 23 through the fixing holes 24. Tying members 25 are inserted at intervals into the slots 26 and moved vertically so that the anchoring portion of each tying member lies on a course of blocks 27, 28 or 29. In the event of the wall formed by the courses of blocks 27, 28 and 28 subsiding the tying members side downwards along the slots in the vertical member 21 without the formation of cracks.

In an alternative embodiment, see Figure 5, a vertical member 31 has fixing holes 32 and vertical stiffening bumps 33. The vertical member 31 carries two rows of vertically oriented 'S' shaped slots 34. The slots 34 in each row are displaced from each other vertically so that there is at least one slot available along the whole length of the vertical member 31. The portion of the member 31 adjacent to each slot 34 is pressed outwardly around each slot.

This is illustrated in one instance by portion 35. The ends of the slots 34 terminate in a circular aperture 36.

The tying member, see Figure 6, has a flat disc shaped head portion 37 attached to an 'S' shaped end portion 38 by a shaft 39. The apertures 36 have a diameter slightly larger than that of the head 37 of the tying member. In use the head 37 of the tying member is inserted into the aperture 36 and the tying member is directed along the slot 34 until the vertical portion- is reached. The tying member is rotated3 if necessary, so that the 'S' shaped anchoring portion lies in a horizontal plane. The anchor portion is laid on the surface of the uppermost course of blocks or bricks comprising a wall under construction as described previously.

Claims

1. Apparatus for tying a first, existing, wall to a second, new, wall comprising a vertical member adapted to be rigidly attached to the first wall and tying member adapted to be retained within the structure of the second wall and having engagement means for connection with the vertical member, characterised in that, the vertical member carries vertically oriented slots and the tying member is adapted to slidably engage the slot prior to retention in the second wall.

2. Apparatus as claimed in claim 1 characterised in that the tying members have 'T' shaped heads having a thickness less than the width of the vertical slots and can slidably engage the slots by insertion followed by rotation through a right angle.

3. Apparatus as claimed in claim 1 characterised in that the tying members have flat circular heads having a diameter greater than the width of the vertical slots and the vertical slots terminate in circular apertures adapted to receive the heads of tying members.

4. Apparatus as claimed in claim 3 characterised in that the vertical slots are 'S' shaped with a straight central portion and both ends terminating in a circular aperture.

5. Apparatus as claimed in any of the preceding claims characterised in that the tying member comprises a head portion adapted to engage the vertical slot in the vertical member and an anchoring portion adapted to be retained in set mortar.

6. Apparatus as claimed in claim 5 characterised in that the anchoring portion of the tying member is 'S' shaped.

7. Apparatus as claimed in claim 5 characterised in that the anchoring portion of the tying member is in the form of a loop or a series of loops.

8. Apparatus for tying a first, existing, wall to a second, new, wall as claimed in claim 1 and as herein described.

9. Apparatus for tying a first, existing, wall to a second, new, wall as herein described with reference to the accompanying drawings.