GB2063329A - Wall-ties - Google Patents

Abstract

A wall-tie is formed of sheet material and has a central moisture barrier formed by a drip edge 46, 47 draining condensation in a cavity to the centre. One limb of the tie may be turned through a right angle to provide a bracket fixture to a timber frame inner skin. <IMAGE>

Description

SPECIFICATION Wall-ties Technical Field of the Invention The invention relates to wall-ties.

Background Art In timber-frame construction buildings, that is buildings which have an inner timber frame or skin and an outer brick or block work skin, the timber frame often shrinks with the result that the relative dispositions of the two skins can alter, with possible detriment to the stability of the structure or destruction of or deterioration in a finish such as plaster. Wall-ties are often used to try to prevent relative movement. Also, in brick veneer or masonry cavity walls, it is often necessary to incorporate a wall-tie or ties in order to try to tie the two skins together.However, proposed wallties have the disadvantage that they provide a bridge for moisture condensing in the cavity between the skins, with the result that condensation running down the inner surface of the outer skin strikes the wall-tie and flows across it to the inner timber frame or brick or block work skin which gives rise to dampness of the inner skin with, again, deterioration in or destruction of decoration, such as plasterwork and possible warping of the timber frame where this is used.

Furthermore, such proposed wall-ties are not flexible enough so cannot accommodate some relative movement between the skins.

Disclosure of the Invention It is an object of the invention to provide a walltie which seeks to overcome the disadvantages of the prior waIl-ties.

According to one aspect of the invention there is provided a wall-tie for a multi-skin cavity wall, comprising a limb for anchorage with one skin of the wall, another limb for anchorage with a skin of the wall adjacent the one skin, the limbs being constructed together, and means for preventing or hindering moisture transfer in use to the inner skin.

An advantage which may be obtained owing to the invention is that a relatively stiff yet flexible wall-tie is obtained which nevertheless does not provide a bridge or path for moisture, in use, between adjacent skins of a multi-skin wall.

The moisture-preventing or hindering means may comprise one or more downwardly (in use) directed lips. This is a relatively simple construction which provides a path for condensed moisture whereby it can collect at the lips and condense to drops which can then fall down the cavity to a moisture-deflecting plate.

The or each lip may be at a lateral edge of the wall-tie, preferably at the connector, connecting the limbs. This provides a relatively simple construction which is relatively easy to make.

The wall-tie may include means to provide enhanced stiffness of the wall-tie. This enables the wall-tie to be stiff yet flexible to resist compression in a generally horizontal or vertical direction, yet can accommodate torsional flexing while holding adjacent skins of a cavity wall in which it is installed in desired relative dispositions.

The stiffness-providing means may comprise a depression, which depression may be elongate, of U-shape in cross-section and have rounded ends.

This is a simple yet effective stiffener and can be incorporated in the wall-tie in a relatively simple manner during manufacture.

There may be means to enhance the anchorage of the wall-tie in the wall, and this means may comprise deformations in the limb(s). The deformations in use grip in mortar between courses of bricks or blocks of a skin.

One limb of the wall-tie may lie at substantially right angles to the other limb, so that in use the upright limb may lie along and in contact with the inner skin of the skins of the wall, the upright limb being secured by screws or nails through holes comprising the anchorage-enhancing means.

According to a second aspect of the invention there is provided a wall including a wall-tie as hereinbefore described.

Wall-ties embodying the invention are hereinafter described, by way of example, with reference to the accompanying drawings.

Brief Description of the Drawings Fig. 1 shows a plan view of a first wall-tie; Fig. 2 shows a longitudinal sectional view of the wall-tie of Fig. 1 taken on the line II--II of Fig. 1; Fig. 3 shows, to a larger scale, a bottom plan view of a second wall-tie; Fig. 4 shows a side elevational view of the wall tie of Fig. 3; Fig. 5 shows a front elevational view of the wall-tie of Figs. 3 and 4; Fig. 6 shows, to a smaller scale than that of Fig.

3-5, a fragmentary perspective view of part of a third wall-tie; Fig. 7 shows, to a smaller scale than that of Figs. 3-5, a fragmentary perspective view of a fourth wall-tie; Figs. 8-11 1 show respectively a perspective view, plan view, side elevational view and underneath plan view of a fifth wall-tie; Figs. 12-1 6 show respectively a plan view, side elevational view, underneath plan view, perspective view and end elevational view of a sixth wall-tie; Figs. 1 7-20 show respectively a perspective view, underneath plan view, top plan view and side elevational view of a seventh wall-tie;; Figs 21-25 show respectively a rear perspective view, a front perspective view, a front elevational view, a side elevational view and a plan view of an eighth wall-tie; Figs. 2629show respectively a perspective view from in front, a side elevational view, a front elevational view, and a bottom plan view of a ninth wall-tie; Figs. 30-32 show the wall-tie of Figs. 12-1 5 in use in a brick or masonry cavity wall, Fig. 30 showing a side elevational view, Fig. 31 showing a section in the direction A-A, and Fig. 32 showing a perspective view of the wall; and Figs. 33-35 show the wall-tie of Figs. 26-29 in use in a timber frame wall, Fig. 33 showing a side elevational view, Fig. 34 showing a section in the direction A-A, and Fig. 35 showing a perspective view of the wall.

Best Modes for Carrying out the Invention Referring to the drawings, the wall-ties shown are for insertion between adjacent skins of a multi skin brick or timber frame cavity wall, particularly a cavity wall having an inner and outer skin. Figs.

1 and 2 show a wall-tie 1 which is substantially planar, being formed from galvanised mild steel and comprising a first part 2, for anchoring in one (say the outer) skin of the wall, and another part 3 for anchoring in the other (the inner) skin of the wall (the skins not being shown), a connector 4 connecting the two parts 2 and 3, and means in the form of two lips 5 and 6 at the lateral edges of the connector 4 for preventing or hindering transfer of moisture between the two skins of the wall, particularly from the outer to the inner skin, across the cavity. The connector 4 also has means providing stiffness of the wall-tie, in the form of an elongate depression 7 of U-shape in cross-section and having rounded ends which in use extends above (as viewed) the plane of the parts 2 and 3.

The lips 5 and 6 each comprise a turned down flange having a semi-circular part 8 struck out to provide two points 9 and 10 at which moisture can coalesce to form droplets which can drop off into the cavity.

Each part 2 and 3 has a plurality of through holes 10 struck through it.

The wall-tie 1 is made in one piece from sheet galvanised mild steel the lips 5 and 6, depression 7 and the holes 10 being formed by suitable metal working machinery such as a metal punching and forming machine.

In use, the cavity wall is built up. When it is desired to strengthen the wall,-the wall-tie 1 is inserted between the skins (not shown) so that the parts 2 and 3 lie in a respective skin of the wall, say the inner and outer skin. Mortar between courses passes through the holes 10 and helps to anchor the wall-tie in position.

The dimensions of the wall-tie are such that the connector 4 lies in the cavity. Any moisture condensing in the cavity runs down the lips 5 and 6 and collects at the points 9 and 10 in droplets which then drop from the wall-tie 1 down the cavity to a deflector or damp resistor plate which directs the moisture to the outside of the wall. The depression 7 acts to stiffen the wall-tie 1 and to render it flexible yet stiff so that it resists compression and tension forces yet can accommodate torsional changes.

Referring now to Figs. 3-5, the wall-tie 20 shown is similar to the wall-tie 1 except that limb 30 lies in a plane at substantially 900 to the plane of the limb 21.The limbs 21 and 30 are integral with and connected by a connector 22 which includes means 23 for preventing or hindering transfer of moisture between the outer and inner skin, and stiffness-providing means. The means 23 comprise two turned-down lips 24 from each of which a semi-circular piece of material has been removed to provide at each side of the horizontal (as viewed) part two points 25 and 26 at which moisture can coalesce into drips.

The stiffness-providing means comprise a depression 27 which extends into the (vertical) limb 30.

The limb 21 has a plurality of circular through holes 28 and the limb 31 has three elongate holes 29.

The wall-tie is for use with timber frame construction walls in which there is a timber inner frame or wall and an outer brick or block work wall' separated by a cavity.

In use of the wall-tie 20, the limb 21 is laid inbetween courses of brick or block work forming the outer skin so that mortar between the courses passes through the holes 28 and helps to anchor the wall-tie 20 in the outer skin.

Securing devices such as nails or screws are inserted through the holes 29 into the timber frame, against which the right hand (as viewed) surface of the limb 30 lies. The elongate nature of the holes 29 enables the position of the wall-tie 20 to be adjusted in position during installation, and also enables a vertical movement of the inner skin to be accommodated after installation while still maintaining the wall-tie 20 anchored to the inner skin or timber frame construction. The depression 27 extends into both limbs 21 and 30 and is of U-shape in cross-section, has rounded ends and provides stiffness of the wall-tie 20 while retaining its flexibility.The wall-tie 20 thus ties the inner and outer skins together, particularly when the inner timber frame skin shrinks, so maintaining the relative dispositions of the skins, but is flexible so that slight lateral torsional or vertical movements can be accommodated, so maintaining the integrity of the structure or finish such as plasterwork.

Referring now to Figs. 6 and 7, there is shown anchorage-enhancing means in the form of teeth 31 and 32 struck out from the parts 2 or 21. The teeth 31,32 may be used in either embodiment described. In Fig. 6 the teeth 31 protrude downwardly, as viewed, and in Fig. 7 they protrude upwardly, as viewed, at an angle to the plane of the part 2 or 21. The teeth 31 and 32 are in use embedded in mortar between courses of brick or block work, and help to anchor the wall-tie 1 or 20 in positions. The teeth 31 and 32 are struck out in a metal punching or forming operation during formation of the wall-tie.

Referring now to the embodiment of Figs.

8-11, the wall-tie 40 as shown is for use in a brick, block or masonry cavity wall. The wall-tie 40 has a part of limb 41 for insertion in one (say the outer) skin and a part of limb 42 for insertion in the other (say the inner) skin of the wall. The two limbs 41 and 42 are connected by a connector 43 to provide an integral construction.

The two limbs 41 and 42 each taper towards the connector 43 and also turn and curve downwardly to provide lips 44 and 45 each of which has a semi-circular part struck out to provide two points 46 and 47 at which moisture can coalesce to form droplets which can drop off into the cavity. The lips 44 and 45 are each concave as viewed in Fig. 10.

The wall-tie 40 also has means providing stiffness, in the form of a raised element 48 of Ucross-section which extends across the connector 43 into each limb 41 and 42 to provide parts 49 of the element 48 which are narrower and lower (fig. 10) than the element 48. Each limb 41 and 42 has symmetrically arranged deformations or depressions 50 of circular shape which extend or protrude downwardly (as viewed in Fig. 10) from the plane of each limb. The deformations 50 are "blind" and thus are in the form of cups. Each limb 41 and 42 also has three upwardly closed, transversely extending elongate deformations or dimples 51, of U-shape in cross-section which extend upwards out of the plane of each limb (Fig.

10). Each deformation 51 is of the same height as the parts 49. The deformations 51 are staggered with respect to the deformations 50 as considered lengthwise of the limbs. In use of the wall-tie 40, the cavity wall is built up to a desired height.

When it is desired to strengthen the wall, the walltie is laid in place across the cavity so that the limb 41 is on a bed of mortar of the outer skin and the limb 42 is on a bed of mortar of the inner skin, both beds being at the same height. The connector 43 then lies in the cavity with the lips 44 and 45 approximately centrally located in the cavity. The wall is then built up, more mortar being placed on the limbs 41 and 42. The deformations 50 and 51 bed into the mortar both above and below the plane of the limbs and provide a very firm anchor of the wall-tie 40 in the wall. The lips 45 and 46 collect any water which tries to "bridge" the cavity by running along the wall-tie and so prevents or hinders passage of moisture from the outer to the inner skin. The inner skin is therefore protected from attack by moisture while at the same time being tied to the outer skin.The moisture collected ultimately drops off the points 46 and 47.

The element 48, 49 acts to stiffen the wall-tie so that it resists compression and tension forces imposed on it by movement of the wall, particularly the inner skin which tends to "settle", while accommodating torsional changes.

The wall-tie 60 of Figs. 12--16 is similar in construction and use to that of Figs. 8-11, so numerals are omitted for clarity. The main differences are that the limbs 41 and 42 of the wall-tie 60 have "wavy"edges, which enhance adhesion in the mortar, and the connector 48 is narrower than that of Figs. 8-11. Importantly, too, the element 48 in the form of means providing stiffness which extends between the two limbs 41 and 42, is of constant cross-section and is raised so that it is of triangular shape in side elevation (Fig. 14), the apex 61 of the triangle being substantially centrally of the wall-tie, over the points 46 and 47.The narrow folded connector enhances the strength of the wall-tie 60, while the element 48 being raised, also prevents or hinders passage of moisture along the length of the wall-tie, as an upwardly inclined obstacle is presented. Also, the relative narrowness of the connector 48 and the upwardly directed triangular raised element also ensure that mortar droppings are not encouraged to adhere to the wall-tie 60 should they fall onto it from above when a wall in which the wall-tie is inserted is being built. The mortar slides off, and so does not build up to provide a "bridge" for moisture. The lateral width of the connector 48 in the wall-tie 60 is less than the length of the deformations 51.

The wall-tie 70 of Figs. 17-20 is also similar in construction and use to those of Figs. 12-1 6, so again, numerals are omitted for the purpose of clarity.

The wall-tie 80 of Figs. 21-25 is for use in a timber frame wall and is similar in construction and use to the wall-tie of Figs. 3 and 4. The walltie 80 has a part of limb 81 which in use is secured to a timber frame of an inner skin of the wall and a part of limb 82 which is substantially at 900 to the plane of the limb 81. The limb 82 is received in use in a layer of mortar in an outer, brick skin of the wall. The two limbs 81 and 82 are integral with and connected by a connector 83 which includes means in the form of lips 84 and 85 for preventing or hindering transfer of moisture from the outer skin to the inner skin, and stiffening-providing means in the form of a raised channel-shaped element 86.The two limbs 81 and 82 turn and curve inwardly and downwardly to form the lips 84 and 85 and each has a curved part struck out to provide two points 87 and 88 (Fig. 24) at which moisture can coalesce into drips. The stiffness-providing means comprises a channel-shaped element or deformation 86 projecting forwardly, that is to the right as viewed in Fig. 22. The deformation 86 extends into both limbs 81 and 82 and along the connector 83.

The limb 86 has securing means in the form of holes 89 through which pins, screws or the like can be inserted into the timber frame. The limb 82 has eight symmetrically arranged cup-shaped imperforate deformations 90 which protrude from the plane of the limb 82 in a downwards direction (Fig. 24). There are also four spaced raised elongate deformations 91 which extend transversely of the length of the limb 82. The deformations 90 and 91 provide a firm anchorage of the limb 82 in a mortar course in the outer skin of the wall.

In use of the wall-tie 80, the wall is built up to a required height and the limb 82 is placed on a bed of mortar so that the connector 83 spans the cavity and the rear (to the left as viewed in Fig. 22) surface of the limb 81, parallel to and in contact with the timber frame. Securing means such as nails are then inserted in the holes 89 and driven into the timber to secure the limb 81 in position.

The brick outer skin is then built up to the required height, the limb 82 being encased in the skin. The deformation 90 and 91 provide an anchor in the mortar of the outer skin. The element 86, which has rounded ends provides stiffness whilst retaining flexibility. The wall-tie 80 then ties the inner and outer skins together, particularly when the inner timber frame shrinks; so maintaining the relative dispositions of the inner and outer skins, but is flexible so that torsional or vertical movements can be accommodated, so maintaining the integrity of the structure and finish such as plasterwork.

The wall-tie 100 shown in Figs. 26-29 is also for use in timber frame cavity walls. The wall-tie 100 has a part or limb 101 for securing to a timber frame inner skin and a part or limb 102 for anchoring in a brick outer skin of a cavity wall. The limb 102 has upward deformation 103 and downward circular cup-like deformations 104 (Fig.

27) to enhance anchorage. The deformations 104 are arranged in two parallel rows along the edge of the limb 102, the deformation being notionally circular in plan and part of the circumference thereof intercepting the adjacent edge. The two limbs 101 and 102 are connected buy a connector 105 comprising inwardly curved plates or parts 106 which extend in an initial downward part 107 and then in an upward part 108 between the plane of the limb 102 to the base of the limb 101 (Fig. 26). A curved part is struck out of the parts to provide points 109 and 110 from which moisture can drip. The upward curve 108 of the parts 106 (to the left as viewed in Fig. 27) provide an obstacle to the passage of moisture from right to left (as viewed, Fig. 26 and 27).The parts 106 therefore comprise means to prevent or hinder transfer of moisture from the outer to the inner skin.

The connector 105 also includes an element or deformation 111 which is of channel-shape in transverse cross-section and which is downwardly open, in use of the wall-tie 100. The deformation 111 is elongate and has a part 112 extending upwardly (Fig. 27) from the plane of the limb 102 at an acute angle to a position intermediate the length of the deformation 111. A second part 113 continues to the limb 101, which it joins at or near its base 114, which base 114 is in a plane spaced, in use, above the plane of the limb 102. The deformation 111 provides a stiffener for the walltie 100. In use, if the inner skin moves downwards for whatever reason, such as shrinkage, this movement can be accommodated by the parts 111 and 112 of the "V" of the deformation moving together so that the angle at the apex 115 decreases.This movement nevertheless maintains the upward inclination of the part 112, so preventing passage of water to the inner skin. The deformation 111 stiffens the wall-tie against compressional or tensional buckling.

Figs. 30-32 show the wall-tie 6 in position to tie together the skins of a cavity wall having a brick veneer skin 120 and a blockwork or brick 130 skin separated by a cavity 140. It can clearly be seen that both limbs 41 and 42 are embedded in mortar layers in each skin which are in approximately the same horizontal plane, and that the connector is the part of the wall-tie which is exposed in the cavity 140. Fig. 32 shows the wall-tie laid in place prior to building up the skins of the wall over it.

Figs. 33-35 show the wall-tie 100 in position to tie together the skins of a cavity wall having a brick veneer outer skin 1 50 and a timber frame inner skin 160, separated by cavity 170. The timber frame comprises a plurality of upright spaced apart and substantially parallel timber studs 1 51 to the cavity side of which is secured a plywood facing 152 (which has a moisture membrane 153 on the cavity side). A plasterboard facing 154 is secured to the side of the studs 151 remote from the cavity 170.

The limb 102 is anchored in a mortar course of the brick veneer skin 151, and the limb 101 is secured to a stud 151 by nails or pins inserted through the two holes.

The lips 106 are clearly seen to be in the cavity.

In every embodiment, the limb which is anchored in the outer skin is of sufficient length for the holes 10 or 28 or deformations to be covered and for the connector to be clear of the inner surface of the outer skin.

It will be understood that the invention abovedescribed and shown in the accompanying drawings can be modified in a number of ways.

For example, the wall-ties can be made of steel coated with a corrosion resistor other than a galvanised layer, for example a layer of chlorinated rubber such as polytetrafluorideethylene; or the wall-ties may be made of stainless steel.

Also, in the embodiment of Figs. 3-5, the holes 29 may be circular.

In all the embodiments, the wall-ties are made in one piece from a single metal sheet. It will be understood however, that the limbs may be initially separate and are then connected together.

It will be appreciated that any downward movement of the inner skin which would otherwise tend to provide a slope of the wall-tie downwardly towards that skin is negated in the wall-ties above-described and shown in the drawings because the lips prevent the transfer of moisture across the cavity to the inner skin.

Claims (23)

1. A wall-tie for a multi-skin cavity wall, comprising a limb for anchorage with one skin of the wall, another limb for anchorage with a skin of the wall adjacent the one skin, the limbs being connected together, and means for preventing or hindering moisture transfer in use to the inner skin.

2. A wall-tie according to Claim 1, the means for preventing or hindering moisture transfer comprising a downwardly (as considered in use) directed lip.

3. A wall-tie according to Claim 1 or Claim 2, the means for preventing or hindering moisture transfer comprising two separate downwardly (as considered in use) directed lips.

4. A wall-tie according to Claim 2 or Claim 3, the or each lip being at a lateral edge of the wall tie.

5. A wall-tie according to Claim 4, the or each lip comprising a flange curved inwardly and downwardly, as considered in use, of the wall-tie.

6. A wall-tie according to Claim 5, in which the or each flange includes a depending point at which moisture can collect.

7. A wall-tie according to Claim 6, in which the or each flange has two spaced points at which moisture can collect.

8. A wall-tie according to Claim 6, in which the two spaced points are separated by a semicircular edge portion of the wall-tie.

9. A wall-tie according to any preceding claim, including means to provide increased stiffness of the wall-tie.

1 0. A wall-tie according to Claim 5, the stiffness-providing means comprising an element of generally channel-shape in cross-section formed in the wall-tie.

11. A wall-tie according to Claim 10, the element being elongate, and having rounded ends, and being downwardly open, as considered in use of the wall-tie.

12. A wall-tie according to Claim 10 or Claim 11, the element extending from one limb to the other limb.

13. A wall-tie according to any preceding claim, the limbs lying substantially in the same plane.

14. A wall-tie according to Claim 12, the element being of triangular shape as considered in side elevation.

15. A wall-tie according to any of Claims 1 to 12, the plane of one limb being substantially at right angles to the plane of the other limb.

16. A wall-tie according to Claim 15, the element comprising a first upwardly, in use, inclined part extending from one horizontal, in use, limb and a further inclined part extending from the first part at a different angle to join with the limb which is substantially vertical in use.

1 7. A wall-tie according to any preceding claim, at least one of the limbs having means to enhance the anchorage of the wall-tie in or with its respective skin.

18. A wall-tie according to Claim 17, the anchorage enhancing means comprising deformations in the limb.

19. A wall-tie according to Claim 18, the deformations comprising depression and separate raised dimples.

20. A wall-tie according to Claim 19, the depressions and dimples being in both limbs.

21. A wall-tie according to Claim 19, the depressions and dimples being in one limb, the other limb having holes through it.

22. A wall-tie for insertion between adjacent skins of a multi-skin wall, substantially as hereinbefore described with reference to and as shown in any one of the accompanying drawings.

23. A multi-skin wall including one or more wall-ties according to any preceding claim.