GB2274663A - Building structure and brick tie therefor - Google Patents

Abstract

The invention provides a brick tie with a gripping section 302, connected by a non-twistable connection section 305 to a gripped section 304. The gripped section 304 includes openings 306, 308, through which mortar can extrude. The tie may be used to secure a former into a wall aperture, e.g. for a window. <IMAGE>

Description

BUILDING STRUCTURE AND BRICK TIE THEREFOR FIELD OF THE INVENTION This invention relates to a building structure and to a brick tie therefor.

BACKGROUND TO THE INVENTION There is an increasing trend for buildings to be constructed using where possible factory-built sub-assemblies, since tbse can be accurately pre-formed to size and shape. Such buildings can still have an overall distinctive and individual appearance pleasing to purchasers notwithstanding that they share common components, units or sub-assemblies.

This approach to building construction is widely believed to have improved the quality of recent buildings, particularly of high-rise buildings where renovation tools are difficult to store at the workplace. For mass-housing developments also, where the need for renovation or replacement may be caused by or only noticed by follow-on workers, the general reduced need for inspection and re-working consequent upon the fitting of pre-formed sub-assemblies is of advantage to tb builder, and to the subsequent building occupier.

One sub-assembly for which this approach has been widely adopted is the glazing unit, nowadays usually manufactured off-site by specialist glazing manufacturers, to the size and performance specified by the builder or architect.

It is desirable that the building structure have a "preformed" opening into which a pre-formed wall panel such as a glazing unit can subsequently be fitted, rather than for instance the building wall having a simple brick opening or being built around the window unit.

Thus it is nowadays preferred that the building wall be built around a former, which usefully then becomes an "inbuilt" former providing a mounting frame ready to receive the pre-assembled wall panel. It is important that the former accurately be held by the bricks during the laying of successive brick courses, and also that the former be held against wind movement and the like particularly until the brickwork around the former (mounting frame) has been completed or substantially completed, and the mortar between the bricks has set.

DISCLOSURE OF THE PRIOR ART One approach permitting the use of pre-fabricated building components was taught in USA patent 4,448,391 wherein the wall opening was defined by an outer frame into which a ready-glazed unit could subsequently be fitted We also utilised this approach in the teaching of our international application WO 91/14066.

Our application WO 91/14066 also showed outer frame mounting arrangements using standard so-called "brick ties", as long used to tie cavity walls of brick or concrete blocks or the like.

The standard brick ties are of twisted wire, with a gripped section and a gripping section connected by wire twists.

The relative orientation between the sections can be changed by rotation of the twists, to a tighter or less tight twist condition.

DISCLOSURE OF THE INVENTION We now provide a brick tie having a gripped section and a gripping section, characterised by a non-twistable connecting section joining these sections. In use the gripped section is layable on mortar, thereafter to be trapped by a brick laid thereabove; and the gripping section is fittable within a standard tie recess in an outer frame member, such as proposed in WO 91/14066.

We also provide a brick tie having a gripped section and a gripping section characterised in that the gripped section is a recessed plate. Preferably the plate walls defining the recesses are between one and five times the thickness of the plate, whereby to ensure rapid and even flow of wet mortar onto the upper surface in use of the plate when the gripped section is presented during brick laying.

BRIEF DESCRIPTION OF THE DRAWINGS Fig.1 is of an embodiment of mounting frame fitted in a "new build" structure; Fig.2 is a sectional view of the mounting frame of Fig.1; Fig.3 is a plan view of a wall tie, fittable to the mounting frame of Fig.2; Fig.4 is a sectional view of a wall tie of Fig.3, along the line IV-IV; and Fig.5 is a schematic view of the wall tie in use with the mounting frame of Fig.2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the arrangement as shown generally in Fig.1, a bricklayer will typically lay a line of bricks 60 and blocks 70 to a selected height; he will then lay a further layer of either the bricks or blocks, position the column 200 (Fig.2) of a pre-formed rectangular mounting frame 230 against the extra layer, and then clamp the column 200 in position by laying further bricks or blocks i.e. so as to sandwich the column in the cavity gap 100. Since each frame part of the component 230 has its own column outwardly extending therefrom, further bricks and blocks laid around the former act more firmly to locate the mounting frame 230; when the mortar between the bricks and blocks has set, this mounting frame can only be removed by partial dismantling of the wall.The mounting frame defines a wall opening 120 of preselected size.

In this embodiment the mounting frame 230 and column 200 are integral. Usefully the frame and column will be from an extruded plastics strip, cut to length, mitred at the corners and connected to identical (or similar) cut lengths to form a square (or rectangular) former.

The cavity between bricks 60 and blocks 70 is typically 50mm, but might be 60mm, 75mm or 100mm, to U.K. industry standards. Column 200 is of a narrower width i.e. 38mm, to allow for cavity gap variations e.g. spilled mortar, but perhaps with spacer elements (not shown) secured to it for the wider gaps; the spacer elements would also include tie recesses 211a, 211b.

In order that the mounting frame 230 can be rigidly affixed, even in the partially built wall condition of Fig.l, it is necessary that those wall ties which have been utilised firmly locate the mounting frame. This is achieved by the tie 300 of Figs.3,4.

Tie 300 has a first gripping section 302 and a second gripped section 304, connected by non-twistable connecting section 305.

First gripping section 302 has outwardly divergent planar arms 303 which tightly grip and fit within respective tie gap 211a or 211b; second gripped section 304 is adapted to locate between upper and lower bricks or blocks seated on the mortar. In this embodiment the arms are rigid and nonrotatably mounted to connecting section 305. Relative linear and pivoting movement between tie 300 and tie recess 211a, 211b is thereby prevented i.e. if mounting frame 230 is to move, then tie 300 must also move therewith. It follows that if tie 300 can have its gripped section 304 properly located, then there will be significant resistance by the gripping section 302 against relative movement of the mounting frame 230.

In order to ensure rigid securement of the gripped section 304 of the tie, this is shaped to have a significant width but narrow depth, the width dimension includes openings 306,308 of a size selected to ensure that no point on the upper surface 310 of the tie as viewed in Fig.3 is further from a tie edge 312 than ten times the depth 'd' of the tie as viewed in Fig.4, and preferably no more than three times the depth of the tie.

Thus when the tie is laid on "wet" concrete or mortar as a preliminary to the next layer of bricks or blocks being laid, the mortar can both flow evenly across the underface in use, and extrude through the openings 306,308 and across the upper surface 310, so that the tie will be immovably retained by the concrete or mortar, once this has set.

Furthermore, since the most frequent mishap of the mounting frames in the partially built cavity wall condition of Fig.1 is that the mounting frame is caught by a gust of wind, and is blown over taking with it some or all of the wall whose mortar has yet to set, the use of a generally flat tie of large width helps prevent such mishaps since it relies for holding not simply upon the shear strength of the mortar, but also on the mortar compression resistance and the weight (and width) of the brick or block thereabove.

Thus we have provided an improved tie which greatly eases the task of builders, and for instance allows them to reach the partially built cavity wall condition of Fig.1, and to leave the mounting frame in that condition whilst departing, for instance for a lunch break, confident that the brick and/or block laying will not have to be repeated, and that the mounting frame will not have been damaged or defaced by a mishap.

Usefully the ties will be provided between every third layer of bricks or blocks. Ties can be fitted to one or both sides of the column 200.

Preferably, the ties are of rigid plastics material, and thus have the additional advantage as compared to metal ties that they, together with column 200, thereafter provide a low-conducting thermal barrier between the cavity walls.

Also, the plastics can be chosen to be non corrodable by the constituents of the mortar, or atmosphere within the cavity wall, and so the increasing concern of the authorities that many ties nominally holding cavity walls together are in fact ineffective (being corroded away) after a relatively short period, can be met.

Particularly, if the ties are of PVC, there is the enviromental advantage that former PVC products can be reground, and the granules so formed remade into ties according to the invention. Thus the problem of disposing of former PVC items is partially solved.

Claims (5)

1. A brick tie having a gripped section and a gripping section which is a recessed plate, the sections being joined by a non-twistable connecting section.

2. A brick tie having a gripped section and a gripping section, characterised by a non-twistable connecting section joining these sections.

3. A brick tie having a gripped section and a gripping section characterised in that the gripped section is a recessed plate.

4. A brick tie as claimed in Claim 3, wherein the plate walls define recesses and are between one and five times the thickness of the plate, whereby to ensure rapid and even flow of wet mortar onto the upper surface in use of the plate when the gripped section is presented during brick laying.

5. A brick tie substantially as hereinbefore described with reference to the accompanying drawings.