Various problems are known with conventional bricklaying processes. In such processes a course of bricks is laid together with mortar and further courses laid on top until a wall, pillar or other brickwork is completed. The standard of the brickwork achieved is normally down to the skills of the individual brick layer, in particular in ensuring an even and consistant gap between each successive course of building bricks or blocks. The main problem in inexpertly laid brickwork is the inconsistency of the finished product. For example the mortar beds vary in thickness giving way to different heights of the brickwork from corner to corner as a result of which the wall may not be level. Bricks can be laid in different plains to one another as a result of the inherent softness of the mortar bed. In particular, any pressure that is applied to the brick forces it further into the mortar bed either directly when the brick is being laid or indirectly when pressure is being applied from an additional course above.

Because all bricks cannot be laid with the same pressure these inconsistencies come to light over the finished wall. As a result, even more skilled bricklayers, achieving high quality brickwork is a time consuming task. There is currently a decline in the number of skilled bricklayers who can achieve a good standard of work which in turn gives rise to a problem with the future supply of brick layers as training facilities may not be available.

One known proposed solution to the problem is described in French patent application no. 2600359. According to the arrangements disclosed in this document, a brick laying aid includes a latticed structure having marginal elongate beads. The structure is laid atop a course of bricks with the beads

lying along the edges and mortar is added. Once the mortar has dried the bead can be removed or left in place. In either case various problems arise with this arrangement. Because of the external beading the device needs to be positioned precisely onto the brickwork. Mortar is effectively placed within the device, between the beads, such that when the next course of bricks is laid there will be no excess mortar squeezed from between the bricks such that a satisfactory bond may not be obtained. The recess formed by removing the bead may be too deep and the beads may also prevent the effective shedding of water which can be essential for longterm performance. Furthermore the device requires significant amounts of material and, because of the elongated cylindrical beads, can give rise to production and storage problems.

According to the invention there is provided a building block spacer, method and structure as set out in the appended claims.

Because the spacer elements are enveloped in bonding material in both dimensions, hence effectively embedded in the bonding material such as mortar in use, the spacer elements do not interfere with the brick laying process and in particular allow excess mortar to be squeezed out from between the bricks and scraped off, allowing an improved bond to be obtained. In a preferred embodiment the provision of the spacers at intervals along the long axis of the mat allow improved storage. Preferably the spacers are dimensioned so as to allow the mat to be rolled up. Preferably the spacers are of a width to slightly less than a 100mm standard brick width, most preferably 84mm. This leaves an 8mm spacing either side such that even if the bonding material is recessed the spacer is fully enveloped by the bonding material.

The embodiments of the invention will now be described, by way of example with reference to the drawings of which:

Fig. 1 is a perspective view of a first embodiment of the invention; Fig. 2 is a plan view of the first embodiment; Fig. 3 is a side view of a wall constructed according to the present invention; Fig. 4 is a perspective view of a second embodiment; Fig. 5 is a perspective view of a third embodiment; Fig. 6 is a perspective view of a fourth embodiment; Fig. 7 is a perspective view of a fifth embodiment; and Fig. 8 is a perspective view of a pillar spacer according to the invention.

Referring to Fig. 1 the arrangement is designated generally 10 and includes a course of bricks or blocks 12 with a spacer 14 laid thereon. The spacer 14 comprises a lattice mat, matrix or base 16 with a plurality of upstanding spacer elements 18 extending upwardly therefrom. The lattice is elongate and of width slightly smaller than that of the course of bricks 12 and the spacer elements 18 are arranged at intervals along each long edge of the lattice.

The lattice 16 and spacer elements 18 are preferably formed integrally of plastic material such as a polymer material, polypropylene, PVC, HDPE or nylon. The lattice 16 can be formed in any appropriate manner as will be apparent to the skilled person for example injection moulding, extrusion or a spinning dye. The lattice 16 can be cut to an appropriate length or shape to deal with corners and angles and the spacer elements 18 preferably extend upwardly slightly less than the desired spacing between courses of bricks to take into the account the mortar film that tends to form on the top of the spacers 18.

In the embodiment shown in Fig. 1 the spacer 14 comprises a thin lattice roll 16, approximately 75mm wide, which is unrolled along the length of the bed

joint formed on top of the course of bricks. The roll has a number of 10mm thick bed joint spacers 18 attached at equal intervals to position themselves evenly as the lattice 16 unrolls. Once the roll 16 is in place mortar is applied and the bricklayer can then position the next layer of bricks by applying downward pressure to compress the mortar until the underside of the brick rests on the spacers as shown in Fig. 3. The spacers are arranged at intervals of 180mm centre-to-centre and are cuboids of 10mm side length providing a number of spacers underneath each brick, one at each corner ensuring that the brick is level and plumb. Once the brick is in the correct position determined by the spacers a further spacer 20 in the form of a further cuboid of 10mm at the side can be inserted manually into the perpendicular joint and lateral pressure arranged to compress the mortar in this direction. This process can be repeated for each brick along the bed joints.

During the process the mortar will pass through the lattice arrangement ensuring that the necessary bondings in successive layers has occurred and that the integrity of the structure is assured. Because the spacers are arranged at intervals and are inwardly positioned relative to the course of bricks, when downward pressure is applied excess mortar can be removed ensuring a firm bed. Similarly when lateral pressure is applied excess mortar can be removed.

An alternative embodiment of the invention is shown in Fig. 4. In this case the lattice 30 comprises three spaced elongate support members on which are provided spacer elements 32 at intervals. Each spacer element 32 comprises a transverse ridge connecting the elongate members and generally of triangular cross-section having the desired height. In the embodiment shown the width of the lattice (i. e. between the outermost elongate members 30) is 84mm, the height of the elongate members 30 is 3.5mm and the height of the spacers 32 is 5.5mm providing a total height of 9mm which, taking into account the film of

mortar that forms during the brick laying process, will provide a brick spacing of 10mm. The width of the spacers 32 at the base is preferably between 3 and 4mm and the pitch or interval between the spacers is preferably 40mm Referring to Fig. 5 a further embodiment is shown in which the lattice comprises three spaced elongate members 40 and transverse members 42 at intervals along the elongate members. Projecting upwardly from the transverse members 42 are a plurality of spacer elements 44 of generally cylindrical shape. In the embodiment shown a spacer element 44 is provided at the intersection of the two outer elongate members 40 with each transverse member 42 and two further spacer elements 44 are provided equally spaced along the transverse member 42. As a result corners and angles can be spaced appropriately. However other distributions of spacer elements are of course possible.

Referring to Fig. 6 yet a further embodiment is shown in which a lattice generally designated 50 comprises a plurality of ridge-like spacer elements 52 aligned in the longitudinal direction and generally of triangular cross-section.

In the embodiment shown the spacer elements 52 are distributed at intervals along the lattice 50 and provided in spaced pairs.

Referring now to Fig. 7 yet a further embodiment is shown in which a lattice comprises a plurality of spaced transverse members 60 with elongate boundary elements 62 either side. Provided on the boundary elements 62 are a plurality of spacer elements 64 at intervals each spacer element 64 comprising a disk through a horizontal diameter of which the boundary element 62 passes.

It will be appreciated that the invention can be utilised other than in straight courses of brickwork. For example referring to Fig. 8 a pillar arrangement

comprises effectively a hollow square formed of bricks in a one and a half brick arrangement. In this case the spacer is cut into lengths and laid atop the course of bricks after which the next course is laid in the manner described above.

It will be seen that the invention gives rise to numerous advantages. The spacer is robust, chemically and temperature inert, stable, long-lived and mechanically strong. It is simply and intuitively used and gives rise to a stable structure without affecting the appearance of the structure. The lattice arrangement allows the product to be rolled and because the spacers are provided internally of the brickwork course it allows a firm bedding to be obtained without blocking excess mortar from escaping.

It will be appreciated that the lattice can be of any appropriate configuration that allows water to pass through it and provides a firm bed and in particular can comprise perpendicular or diagonal lattice members which can be extruded, punched out or formed in any other appropriate manner. The spacer elements themselves can be of any appropriate form and dimension and can be formed integrally with the lattice or bonded or adhered to it. The distribution of spacer elements can be varied as required to take into account building block dimensions, right angles or angled joints. The lattice itself can also be formed of any appropriate material not limited to plastic material and including, for example, ceramics, cement or metal materials. The spacer can be formed in lengths or in other shapes and/or of other materials to meet specific brickwork requirements or for use with other types of building blocks such as breezeblocks as appropriate.