GB2509767A

GB2509767A - Damp proof course, cavity tray, flashing or lintel with protruding regions

Info

Publication number: GB2509767A
Application number: GB201300656A
Authority: GB
Inventors: Daniel Cooper
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-01-15
Filing date: 2013-01-15
Publication date: 2014-07-16
Also published as: GB201300656D0

Abstract

A building material i.e. damp proof course 100, 200 for incorporation into a structure including a plurality of bricks (B figure 1C) which comprise a hole or recess in or between the bricks, preferably with bricks which have three holes. The building material may comprise a main body 110 which forms a retaining region, and hollow protruding regions 120 which preferably enter the holes in the bricks. The hollow region is arranged to receive mortar (M figure 1C) to key with one or more further bricks in the structure to thereby form a stronger bond between the layers of bricks. The building material may also be a cavity tray, flashing or a lintel. Later embodiments relate to a structure, and a method of building a structure.

Description

Building Materials

Field of the Invention

The present invention relates to building materials, to structures including a plurality of building elements, and to methods of building a structure.

Background to the Invention

The construction of buildings, walls and other structures from a plurality of building elements, for example bricks or blocks, often involves using a binder material to form a bond between adjacent building elements. After application of the binder material to a building element and the arrangement of a further building element in contact with the binder material, the binder material hardens to form a bond with the building elements in contact it and therefore to form a bond between the building elements. The construction of buildings, walls and other structures comprising a plurality of building elements often requires the incorporation of other building materials into the structure, for example damp-proof courses, cavity trays, flashing and lintels.

The incorporation of these building materials into a structure may require arranging the building material between building elements in a way that interrupts the bond that would otherwise form between a building element the binder material and a further building element.

This interruption may introduce a weakness into the structure.

The problem of building materials interrupting the bond between building elements and causing a weakness in a structure can occur when the building material is a damp proof course. A damp proof course is a substantially water-impermeable membrane which is incorporated into structures to prevent moisture from moving through the structure. For example, a damp proof course may be incorporated into a brick structure comprising bricks regularly arranged in courses or layers and bonded together with binder material, for example mortar. Typically a damp proof course may be incorporated into a brick structure several courses above ground level to prevent moisture from the ground permeating upwards through the structure any further than the damp proof course. The damp proof course is usually arranged several courses of bricks above ground level to prevent water splashing up from the ground reaching bricks which are above the damp proof course, as this water would be able to move through the structure unimpeded. However, the damp proof course interrupts the regular arrangement of bricks and mortar, and produces bonds between the damp proof course and the mortar above and below the damp proof course. The bond between the damp proof course and the mortar is often significantly weaker than a bond between a brick and the mortar and therefore a structure comprising such a damp proof course is often significantly weaker than a similar structure which does not comprise such a damp proof course. It is often observed that walls incorporating a damp proof course fail at the level of the damp proof course.

Known damp proof courses which are intended to provide a stronger bond with mortar, through their material properties, are found in practice to not significantly improve the strength of the bond and therefore structures incorporating these types of damp proof courses can also suffer the same sort of structural weakness problem.

The problem of damp proof courses causing structural weakness mean that freestanding walls such as garden walls, retaining walls and parapet walls are often constructed without a damp proof course. This results in the wall being unprotected from moisture rising through the structure and causing damage such as crumbling or blowing of the bricks, shortening the useful life of the wall. Moisture may also cause minerals to wash out of the bricks and be deposited on the outer surface of the brickwork, and encourage algal growth on the outer surface of the brickwork, giving an unsightly appearance to the brickwork.

The problem of damp proof courses causing structural weakness also leads builders to construct walls, either freestanding or as part of a building, only up to a certain safe height during a working day to offset the risk of the wall being blown over before the mortar has hardened sufficiently for construction to continue.

Cavity trays are damp proof courses intended for use in the construction of buildings with a cavity between inner and outer walls. Cavity trays bridge the cavity between the inner and outer walls and provide a water-impermeable membrane angled downwards towards ground level from the inner wall to the outer wall and are intended prevent rising moisture and also allow any moisture to drain out of the cavity through weep vents. Again the weakness of the bond between the mortar and the tray may present a weak point in a construction including a cavity tray.

Flashing is commonly incorporated into buildings to provide protection from water ingress at the junction of roofing tiles and brickwork, for example. Due to the cost and theft risk presented by using lead for flashing, flashing made from polymer materials is now commonly used. Such flashing is incorporated into brickwork in order to fix it in place to perform its intended function. However, this necessitates a bond between the mortar and the flashing which, as described above for damp proof courses, is relatively weak. This weakness means that flashing made from polymer material is susceptible to storm damage where the bond between the flashing and the mortar may fail, requiring maintenance or replacement.

Lintels that span openings in structural walls may also experience similar problems to those described for damp proof courses, cavity trays and flashing.

It is an aim of example embodiments of the present invention to provide a building material that addresses at least one disadvantage of the prior art, whether identified herein or elsewhere, or to provide an alternative to existing building materials.

Summary of the Invention

In one aspect, example embodiments of the present invention provide a building material for incorporation into a structure including a plurality of building elements which comprise a recess therein or therebetween; wherein the building material comprises a protruding region for entering the recess, the protruding region comprising a hollow arranged to receive a binder material to key with one or more further building elements in the structure.

In another aspect, example embodiments of the present invention provide a structure including a plurality of building elements and a building material, wherein the building material comprises a protruding region for entering a recess in or between building elements, the protruding region comprising a hollow arranged to receive a binder material to key with one or more further building elements in the structure.

Suitably, the building material is arranged for incorporation into a building in which the building elements comprise bricks, or comprise blocks. Suitably, the binder material comprises a mortar, for example a cementitious mortar.

Suitably, the protruding region is for entering a recess in a building element. Suitably, the building material comprises a plurality of protruding regions comprising a hollow. Suitably, the building material comprises protruding regions for entering a recess in more than one building element, or for entering more than one recess in a building element, or for entering a recess between adjacent building elements. Suitably, the protruding regions in the plurality of protruding regions are arranged in a line, for example are arranged rectilinearly across the building material. Suitably, the protruding regions are arranged in groups, for example groups of three, with each group arranged to correspond to a single building element in the structure.

Suitably, the protruding region is generally cylindrical. Suitably, the protruding region is a frog-entering region, when built into the structure. Suitably, the exterior of the protruding region is generally cylindrical. Suitably, the interior of the protruding region is generally cylindrical.

Suitably, the protruding region comprises a passageway which forms the hollow, for example an open ended passageway. Suitably, the protruding region comprises a blind ended hollow.

Suitably, the building material comprises a sheet material, with the protruding region extending beyond the sheet, for example extending generally perpendicular to the sheet. Suitably, the sheet comprises a flexible material. Suitably, the sheet comprises a plastics material.

In some embodiments the building material may comprise a rigid material. Suitable rigid materials include plastics and steel. Suitably, the rigid material is a structural material. For example the purpose of the building material may be primarily to provide structural support.

Suitable structural materials include, for example, steel.

In some embodiments the protruding regions may extend from a retaining region of the building material. The retaining region may be used to retain the building material in a structure comprising a plurality of building elements. The building material may comprise a functional region in addition to the retaining region. The retaining region may be joined to the functional region of the building material. Suitably the functional region provides a function beneficial to the structure. Suitable beneficial functions may include protecting against water ingress, facilitating water drainage from the structure and providing structural support.

The retaining region may be joined to a further retaining region. The further retaining region may comprise one or more protruding regions for entering a recess in a building element. The further retaining region may be substantially free of protruding regions.

The retaining region may be joined to a functional region or a further retaining region to form a continuous member. Suitably the building material is a continuous non-water permeable member.

Suitably, the building material comprises protruding regions extending from one surface of a sheet, for example a lower surface. Suitably, the building material comprises protruding regions extending from opposite surfaces, for example upper and lower surfaces. Suitably, the building material comprises protruding regions extending in different directions at different positions across the building material, for example so that there is no overlap between said protruding regions.

Suitably, the protruding region is shaped to generally confirm with the recess in or between building elements, when the building material is incorporated into a structure. Suitably, the protruding region comprises a frog-entering region. Suitably, the protruding region comprises a generally hollow shell of material. Suitably, the protruding region is undersized with respect to the recess in or between building elements to allow for a layer of binder material to sit between the outside of the protruding region and the inside of the recess. Suitably, said layer may comprise a thickness of more than 1mm, for example more than 3mm or more than 5mm.

Suitably, said layer may comprise a thickness of less than 20mm, for example less than 15mm, for example less than 10mm. Suitably, the hollow may in use be substantially filled with binder material, in order to provide a resistance to deformation of the protruding region.

Suitably, the binder material may in use extend more than 5mm, for example more than 10mm into the hollow.

In some embodiments the building material is a damp proof course.

In some embodiments the building material is a cavity tray.

In some embodiments the building material is a flashing.

In some embodiments the building material is a lintel.

In another aspect, example embodiments of the present invention provide a method of building a structure including a plurality of building elements and a building material comprising a protruding region comprising a hollow, the method comprising the steps of: a arranging building elements from the plurality of building elements to form a partial structure; b providing at least a part of the partial structure with a binder material; c arranging the building material on the partial structure in contact with the binder material; d optionally providing the hollow with binder material and arranging a further building element on the building material in contact with the binder material.

Suitably, the building material and/or structure and/or building elements and/or binder material are substantially as described in relation to the aspects of the invention above.

There are also provided a building material, a structure and a method substantially as described in relation to the aspects above, and/or with reference to the accompanying drawings.

According to the present invention there is provided an apparatus and method as set forth in any appended claims. Other features of the invention will be apparent from the dependent

claims, and the description which follows.

Brief Introduction to the Drawings

For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which: Figure la shows a side elevation of a damp proof course in accordance with an example embodiment of the present invention; Figure lb shows a perspective view of a damp proof course in accordance with an example embodiment of the present invention; Figure ic shows a perspective view of a damp proof course in accordance with an example embodiment of the present invention fitted to a brick wall with mortar; Figure Id shows two damp proof courses in accordance with example embodiments of the present invention fitted to a brick wall with mortar, the damp proof courses partially overlapping each other; Figure 2 shows a perspective view of a damp proof course in accordance with an example embodiment of the present invention, comprising a step; Figure 3 shows a side elevation of a damp proof course in accordance an example embodiment of with the present invention; Figure 4 shows a perspective view of a cavity tray in accordance with an example embodiment of the present invention; Figures shows a perspective view of a flashing in accordance with an example embodiment of the present invention; and Figure 6 shows a perspective view of a lintel in accordance with an example embodiment of the present invention.

Description of Example Embodiments

Figures la to id show, by way of an example, an embodiment of the invention wherein the building material is a damp proof course adapted to be incorporated into a structure including building elements in the form of bricks having three recesses per brick. The damp proof course 100 is a continuous non-water permeable member, comprising a flexible substantially flat main body 110 and nine hollow protruding regions 120. The main body 100 comprises an upper face 111 and a lower face 112. The protruding regions 120 are open at the upper face 111 of the main body to form a hollow, but have a blind end. In this embodiment the main body 110 forms a retaining region. The arrangement of the protruding regions 120 on the damp proof course 100, particularly the spacing between the protruding regions, is such that the protruding regions are able to enter the recesses of the bricks when the bricks are arranged to form a brick structure and bonded together with mortar. In this example embodiment the brick dimensions are 215mm by 102.5mm by 65mm, and the protruding regions are externally 60mm long, 25mm in diameter, and are spaced 45mm apart.

The damp proof course 100 is intended to provide a substantially water-impermeable barrier within a brick structure. In use, a brick structure may be built by standard methods using bricks comprising three recesses per brick and mortar as a binding material. The brick structure may be built up to a certain height, typically three courses of bricks high, to provide a substantially level course of bricks with exposed upper faces. The damp proof course 100 may then be fitted to this brick structure by providing a layer of mortar M to the exposed upper faces of the bricks forming the top course of the brick structure, and arranging the damp proof course 100 in contact with the layer of mortar such that the protruding regions 120 enter the recesses in the bricks and the outer surface 121 of the protruding regions become at least partially coated with mortar which is also in contact with a part of the inner surface of the recesses in the bricks B as shown in Figure lc. When so fitted, the lower surface 112 of the main body of the damp proof course is in contact with the mortar on the upper face of the bricks forming the top course of the brick structure. When so fitted there may be a substantially continuous mass of mortar M covering the lower surface 112 of the main body and the outer surface 121 of the protruding regions 120 in contact with the upper faces of the bricks and the inner surface of the recesses of the bricks respectively. The upper surface 111 of the main body 110 and the inner surface 122 of the protruding regions 120 are then provided with mortar and a course of bricks arranged on top of the mortar. The mortar may form a substantially continuous mass of mortar covering the upper surface 111 of the main body 110 and the inner surface 122 of the protruding regions 120 in contact with the lower faces of the bricks arranged on top of the mortar. Further courses of bricks may then be added to the brick structure using standard methods.

Once sufficient time has passed to allow the mortar to set, the mortar in contact with the outer surface 121 of the protruding regions 120 and the inner surface of the recesses in the bricks, and the mortar in contact with the inner surface 122 of the protruding regions and the lower surface of the bricks arranged on top of the damp proof course 100, stabilises the structure against the bricks above the damp proof course 100 shearing with respect to the bricks below the damp proof course 100, which would correspond to failure of the structure at the damp proof course 100.

In order to provide a damp proof course substantially covering the length of a wall, a damp proof course according to the present invention may be provided in a suitable length to fit the wall. For example, the required length of damp proof course may be cut from a longer piece of damp proof course. Alternatively more then one piece of damp proof course may be arranged to overlap each other. Damp proof courses arranged to overlap may overlap by contacting the upper surface 111 of the main body 110 of one piece with the lower surface 112 of the main body 110 of another piece. Alternatively the damp proof courses arranged to overlap may overlap by inserting a protruding region 120' of one piece, 100' into the inside of a protruding region 120" of another piece 100", as shown in Figure ld.

Figure 2 shows a damp proof course 200 according to another example embodiment, provided with a step 210 adapted to allow the lower part 220 of the damp proof course 200 to be arranged on a brick which is part of a first course of bricks, and allows the upper part 230 of the damp proof course 200 to be arranged on a brick which is part of a second course of bricks, the second course of bricks being higher in the structure than the first course of bricks.

The upper and lower parts 220 and 230 may be considered to be retaining regions and the step 210 may be considered to be a functional region, as they respectively take part in retaining the building material in place in the structure, and perform the damp-proofing function. The damp proof course comprising a step 200 may be used where the brick structure is constructed on sloping ground and the damp proof course has to step up or down one or more courses of bricks in order for the damp proof course to have a reasonably consistent height above the ground.

Several pieces of damp proof course according to example embodiments may be overlapped as described above to provide a damp proof course substantially all around a structure. In other example embodiments the protruding regions may be formed on the damp proof course at the edge regions thereof, with further damp proof material extending therefrom a considerable distance to form a damp proof course sheet. In still further example embodiments the damp proof course may have projections formed within a large sheet, such that the damp proof sheet extends therefrom in two opposite directions from the line of projections.

Figure 3 shows, by way of an example, an embodiment of the invention wherein the building material is a damp proof course adapted to be incorporated into a structure comprising bricks having one recess. Such bricks may be the commonly known frogged' bricks. The damp proof course 300 is a continuous non-water permeable member, comprising a flexible substantially flat main body 310 and three hollow protruding regions 320. The main body 300 comprises an upper face 311 and a lower face 312. The hollow protruding regions are open at the upper face 311 of the main body. The main body 310 in this embodiment may be considered to be a retaining region. The arrangement of the protruding regions 320 on the damp proof course 300, particularly the spacing between the protruding regions, is such that the protruding regions are able to enter the recess of the bricks when the bricks are arranged to form a brick structure and bonded together with mortar. The principle of operation described in relation to the example embodiment of Figures la to ld applies to this embodiment of Figure 3.

Figure 4 shows, by way of an example, an embodiment of the invention wherein the building material is a cavity tray adapted to be incorporated into a structure comprising an outer wall of bricks having three recesses per brick, an inner wall of blocks and a cavity between the outer and inner walls. The cavity tray 400 is a continuous non-water permeable member comprising a lower part 401 for incorporating into an outer brick wall, an upper part 402 for incorporating into an inner block wall, and a bridging part 430 for spanning the cavity between the outer and inner walls. The lower part 401 comprises nine hollow protruding regions 420. The lower part 401 comprises an upper face 411 and a lower face 412. The hollow protruding regions 420 are open at the upper face 411 of the main body. In this embodiment the lower part 401 is considered to be a retaining region and the upper part 402 is considered to be a further retaining region. The bridging part 430 is considered to be a functional region for similar reasons as the corresponding regions described above. The arrangement of the protruding regions 420 on the lower part 401, is such that the protruding regions are able to enter the recesses of the bricks when the bricks are arranged to form a brick structure and bonded together with mortar, as described above in relation of the embodiment of Figures la to Id.

The upper part 402 is substantially flat and suitable for incorporation into a wall constructed from blocks. The bridging part 430 is a substantially flat. The lower part 401, upper part 402 and bridging part 430 are arranged so that when incorporated into a building comprising a brick outer wall, a block inner wall and cavity between the outer and inner walls, a continuous non-water permeable layer is provided which extends from the inner block wall across the cavity at an incline towards the ground to the outer brick wall.

More than one cavity tray according to the present invention may be overlapped as described in relation to the embodiment of Figures 1 a to ld, in order to provide a substantially continuous non-water permeable layer across a wall or within a structure.

Figure 5 shows, by way of an example, an embodiment of the invention wherein the building material is a flashing adapted to be incorporated into a structure including building elements in the form of bricks having three recesses per brick. The flashing 500 is a continuous non-water permeable member comprising a retaining part 510, a vertical part 530 and a roof-shielding part 540. The retaining part comprises three hollow protruding regions 520 which are adapted to enter the recesses of a brick comprising three recesses as described in relation to the embodiment of Figures la to id above. The vertical part 530 abuts the retaining part at a right angle and comprises an upper edge 531 and a lower edge 532. The upper and lower edges 531 and 532 are inclined with respect to the plane of the retaining part 510 which is intended to be horizontal. The roof-shielding part 540 is joined to the vertical part 530 at the lower edge 532 of the vertical part at a right-angle to the vertical part. In this embodiment the retaining part 510 is considered to be a retaining region and the vertical and roof-shielding parts 530 and 540 are considered to be functional regions.

The flashing 500 is intended to provide protection for a structure against water ingress at the join between a roof and a wall. In use the flashing is incorporated into a brick wall as described in relation to the embodiment of Figures la to id above. The inclined part of the flashing is intended to be arranged in a structure such that the inclined part 540 contacts a part of a roof adjacent to a wall, the vertical part 530 contacts a wall, and a continuous water-impermeable surface comprising the roof-shielding 540 and the vertical part 530 covers a part of the wall, a part of the roof and a part of the join between the wall and the roof. Several such flashings and variations thereof may be arranged together and overlapped to cover substantially all of a join between a roof and a wall and thereby provide protection for a structure from water ingress at the join. The angle at which the roof-shielding part 540 is set relative to the retaining part 510 may be chosen according to the pitch of the roof of a given structure. In circumstances where a flat roof meets a wall, the roof-shielding part 540 may be horizontal and therefore not inclined with respect to the retaining part.

Figure 6 shows, by way of an example, an embodiment of the invention wherein the building material is a lintel adapted to be incorporated into a structure including building elements in the form of bricks having three recesses per brick. The lintel 600 is a continuous rigid steel member comprising an outer retaining part 610, an inner retaining part 630, an outer vertical part 640, an inner vertical part 650 and a bridging part 660. The outer retaining part comprises six hollow protruding regions 620 which are adapted to enter the recesses of a brick comprising three recesses as described in relation to the embodiment of Figures la to id above. The inner retaining part 630 is substantially flat and suitable for incorporation into a wall constructed from blocks. The outer vertical part 640 is joined to the outer retaining part 610 at a right angle. The inner vertical part 650 is joined to the inner retaining part 630 at a right angle. The height of inner retaining part 650 with respect to the inner retaining part 630 is greater than the height of the outer vertical part 640 with respect to the outer retaining part 610. The outer and inner retaining parts 610 and 630 are substantially co-planar. The bridging part 660 joins the top edges of outer and inner vertical parts 640 and 650 and is intended to span a cavity in a structure comprising a cavity between an outer wall and an inner wall. The outer retaining part 610 may be considered to be a retaining region. In this embodiment the inner retaining part 630 is considered to be a further retaining region. The inner and outer vertical parts 640 and 650 and the bridging part 660 are considered to be functional regions.

The lintel 600 is intended to strengthen a structure comprising a doorway or window by providing support for the building elements arranged above the doorway or window. In use the lintel is incorporated into an outer brick wall and an inner block wall, both or which are bonded with mortar, by arranging the outer retaining part 610 and the inner retaining part 630 across the top of an opening in the structure intended to form a doorway or window, such that the protruding regions of the outer retaining part enter the recesses in the bricks as described in relation to the embodiment of Figures la to ld above. Further building elements are then arranged on top of the outer and inner retaining parts 610 and 630 using standard methods.

The example embodiments described above may provide a building material, for example a damp proof course, a cavity tray, a flashing or a lintel, which can be incorporated into structure comprising a plurality of building elements bonded together with a binder material, more securely than known building materials. Specifically the hollow protruding region provided on the building material allows binder material to enter the inside of the protruding region and surround the outside of the protruding region during construction and, once hardened, provide resistance against shearing of the structure in a lateral direction. The amount of shearing resistance is linked to the amount and strength of material in the hollow of the protruding regions.

The increase in the strength of the bond between the building material, the building elements and the binding material provided by the protruding region may at least partially compensate for the reduced strength of the bond between the binding material and material used to form the building material compared with the bond between the binding material and the building elements.

The increase in the strength of the bond between the building material, the building elements and the binding material provided by the protruding region may provide a structure incorporating such building material with additional strength compared with a structure incorporating known building material having a similar purpose.

The increase in the strength of the bond between the building material, the building elements and the binding material provided by the protruding region may provide a structure incorporating such building material with additional strength during construction so that a structure may be safe to build to a height which would be unsafe if known building materials having a similar purpose were used.

The increase in the strength of the bond between the building material, the building elements and the binding material provided by the protruding region may provide a structure incorporating such building material with additional strength during construction so that additional weight may be safely added to the structure above the building material sooner than would be possible if known building materials having a similar purpose were used.

The increase in the strength of the bond between the building material, the building elements and the binding material provided by the protruding region may provide a free-standing wall comprising a damp proof course according example embodiments as described herein which has an increased useful life compared to a free-standing wall comprising a known damp proof course.

The construction of buildings, walls and other structures comprising a plurality of building elements often requires the incorporation of other building materials into the structure, for example damp-proof courses, cavity trays, flashing and lintels. The incorporation of these building materials into a structure may require arranging the building material between building elements in a way that interrupts the bond that would otherwise form between a building element the binder material and a further building element. This interruption may introduce a weakness into the structure. These issues may be addressed by example embodiments as described herein.

Although a few preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in any appended claims.

Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification including any accompanying claims, abstract and drawings, and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification including any accompanying claims, abstract and drawings may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification including any accompanying claims, abstract and drawings, or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

Claims 1. A bUlding materI for incorporatbn 1mb a stwcture including a plurailty of building elements which comprise a recess therein or therebetween; wherein the building material comprises a protruding region for entering the recess, the protruding region comprising a hollow arranged to receive a binder material to key with one or more further building elements in the structure.
2. The building matePial accos-ding to ciairn I arranged for incorporation into a building in which the building elements comprise bricks, or comorise blocks.
3. The building matemi according to claims I or 2, wherein the binder material comprises a mortar.
4.. The building materiel according to any preceding claim, wherein the prcUuding region is for entering a recess in a building element.r 5. The building material according to any preceding claim, comprising a. pluraty of protruthng regions comprising a hollow. 0 20 6, The building material according to any preceding claim, comprising protruding regions for entering a recess in more than one buildinq element. r7, The building material according to any preceding claim, comprising protruding regions for entering more than one recess in a building element, 8, The building material according to any preceding claim, comprising prorniding regions for entering a recess beeen adjacent building elements.9. The building material according to any preceding claim, wherein protruding regions in the pluraifty at protruding regions are arranged in a line.10. The building meter according to any preceding claim, wherein the protcudrng regions are arranged in groupa 11. The building material according to any preceding claim, wherein the protruding regions are arranged in groups of three, with each group arranged to correspond to a single building element in the structure.12. The building material according to any preceding claim, wherein the protruding region is generay cyndricaL 13. The buHding materi eccording to any preceding Sim, wherewi the protruding region is a frog-entering region, when built into the structure.14. The building mateñai according to any preceding claim, wherein the exterior of the protruding region is genraliy cylindricaL 15. The building material aoccirdlng b any preceding Sin wherein the interior of the protruthng region is generally cylindricaL 16. The building materiel according to any preceding claim, wherein the protruding region comprises a passageway which forms the hoDow.17. The buliding material according to any one of claims Ito 15, wherein the rotruthng ci) region comprises a blind ended hollow. r04 18, The builthng material according to any preceding claim, wherein the protruding regions 0 20 extend from a retaining region of the building rnat&aL r 19. The buding material according to claim I, comprising a functional region in addition to the retaining region.20. The buiLding material according to claim 19, wherein the retaining region is joined to the functional region of the building material.21. The buliding material according to claim 19 or 20; wherein the functional region provides a function beneficial to the structure.22. The building material according to claim 21, wherein the beneficial function includes protecting against wate inyrss.23. The building material according to daim 21 or 22, wherein the beneficial function includes facilitating water drainage from the structure.24. The buiLding material according to claim 21, 22 or 23, wherein the beneficial function includes providing structur support.25. The building material according to any one of claims 15 to 24, wherein the retaining region is Joined to a further retainirw region.25. The buUding niateria! according to claim 25, wherein the further retaining region comprises one or more protruding regions for entering a recess in a building element.27, The building material according to claim 25, wherein the further retaining region is substantially tree of protruding regions.28. The buildino material according to any one of cime 19 to 27, wherein the retaining region is joined to a functional region or a further retaining region to form a continuous member.29. The building r tenal sccordng to any preceding claim, wherein the building rnaierial is a continuous non-water permeable member.ci) 30. The building material according Ic any preceding claim, wherein the protruding region r is shaped to generally conform with the recess in or between building elements, when the building material is incomorated into a structure. 0 20 31. The building material according lo any precedieg claim, wherein the protmuthng region is underszed with resoect to the recess in or beftween building elements to allow for a layer of r binder matertal to sit between the outside of the protruding region and the inside of the recess.32. The building material according to claim 31, wherein said layer may comprise a thickness of between 1mm and 20mm.33. The building material according to any preceding claim, whe'ein the hollow may in use be substantially fllled with binder material, in order to provide a resistance to deformation of the protruding region.34. The building material according to any preceding claim, wherein the binder material may in use extend more then 5mm into the hollow.35. The building material according to any preceding dam, comprising protruding regions extending from opposite surfaces.35. The buiLdlng material according to any one of claims 1 to 34, comprising protruding regions extending in different directions at different positions across the building material.37. The bufiding rnater according to any preceding claim, comprising a rigid matena!.38. The boflding meteri according to claim 37, wheren the rigid materi is a plastics materiaL 39, The bthlWng material according to daim 37, wherein the rigid material is steel, 40. The budding matedal according to claim 37, 38 or 30, wherein the rigid material is a structural material 41, The buding rnteri& according to any one of Sims 1 to 36, comprising a sheet material, with the protruding region extending beyond the sheet.42. The budinq rnateri according to claim 41, whereui the protruding region extends generaVy perpendicular to the sheet.r 43. The building material according to claim 41 or 42 wherein the sheet comprises a flexible material, 0 20 44. The building material according to any one ot claIms 41 to 13, wherein the sheet comprises a olastics material r 45. The building material according to any one of claims 41 to 44, comprising protruding regions extending from one surface of a sheet.46. The building material according to any preceding claim, wherein the building materi& a a damp proof course.47. The building material according to any one of claims I to 45, wherein the building material is a cavity tray.48. The building material according to any one of claims 1 to whereft' the building material is a tlashing 49. The building material according to any one of claims 1 to 40, wherein the building material is a lintel.50. A structuce including a plurality of bthki!ng elements and a building material, wherein the building material cc nprrsez a protruding region for entering a recess in or between building &ements, the protruding region comnrising a hoow arranged to receive a binder material to key with one or more further building elements in the structure.51 The structure accordLng to claim 50, comprising binder materiaL 52. The structure according to claim 51 wherein the binder material comprises a mortar.
5. The structure accordlng to any one of claims 50 to 52, wherein the plurafity of buthng elements comprise bricks, or comprises blocks.54, A method of building a structure including a puraUtj of building elements end a building material comprising a protruding region comprising a hollow, the method comprising the steps of: C") a arranging boilding elements from the plurailty of building elements to form a partial r structure; (s4 b provtding at least a part of the partial structure with a binder material; O 20 c arranging the building material on the partiS structure in contact with the binder (\J material; d optionally providing the hoHow with binder matedal and arranging a further bufldinci element on the building material in contact with the binder material.55. A building material, a structure or a method substantially as described above, and/or with reference to the accompanying drawings.