GB2420354A

GB2420354A - Plastics building block incorporating a drainage channel

Info

Publication number: GB2420354A
Application number: GB0500972A
Authority: GB
Inventors: Jace Whitaker
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-11-22
Filing date: 2005-01-18
Publication date: 2006-05-24
Anticipated expiration: 2025-01-18
Also published as: GB0425630D0; GB0500972D0; GB2420354B

Abstract

A block includes upper and lower surfaces 3, 4, the upper surface including a pair of connecting formations 2, and at least one orifice 9, of a draining channel, the lower surface a connecting formation 5, such that in use like blocks may be connected together via the formations, the drainage channel conducting moisture out to a lower part of the block. Preferably there are a plurality of drainage openings in the lower surface of the block which in use align with the openings in a vertically adjacent block. The connecting formations may be in the form of recesses and protrusions and the lower surface drainage openings may be located in said protrusions, Figure 7.

Description

BUILDING BLOCK

Field of the Invention

This invention relates to a building block moulded in the plastics material for facili- tating rapid construction of buildings without the need for highly- skilled workers.

Background to the Invention

Conventionally, aside from wholly timber constructions, buildings can be con- structed using bricks or blocks bonded together with a cement or lime mortar. While the results of such techniques are satisfactory, they require a high level of skill and are time- consuming; there is, for example, a limit to the number of courses of bricks or blocks which can be laid before the mortar must be left to allow it to harden, for example over- night. If appropriate skill is not exercised in the preparation of the mortar and the laying of the bricks or blocks, the integrity of the building may be compromised and the appear- ance may be unsatisfactory.

There have been numerous proposals for building systems which reduce the skill 1 5 required for construction and increase its speed. For example, pre- fabricated panels may be assembled on site to increase speed of construction. However, these still require skill in assembly and are relatively costly to manufacture. They often prove to be less durable than conventional building materials.

Children's constructional toys can consist of plastic bricks all blocks which are sim- ply pressed together to provide a desired construction, for example a model building.

While it would appear desirable simply to scale up such toy bricks or blocks to provide a press-together building system, this would not yield buildings acceptable for human habi- tation because of the likelihood of ingress of damp. While plastics moulding techniques permit a high level of accuracy, it is impossible to guarantee perfect mating surfaces at the sides of blocks. It would be possible for moisture to seep in between the blocks when the exterior of the building is exposed to rain. This moisture will tend to flow inwardly and downwardly into the vertical joints between the blocks.

One way of overcoming this would be by the application of a sealant to the joints during construction. However, this would introduce a requirement for a high level of skill in applying a sealant, to ensure an adequate seal while permitting proper assembly of the blocks together. This would to a considerable extent defeat the purpose of adopting such a building system.

Summary of the Invention

Accordingly, this invention provides a building block moulded in a plastics material and comprising an upper surface with a pair of first connecting formations thereon, a lower surface having a second connecting formation thereon, the first connecting forma- tions on one block being adapted to co-operate with the second connecting formations on two other blocks to connect and hold the blocks together in a vertical overlapping ar- rangement, the sides of the blocks being planar so as to rest in close engagement when the blocks are connected together side-by-side, each block having therein a drainage con- duit arranged to conduct moisture through the block and discharge it from a lower part thereof, the drainage conduit having a central opening in the upper surface of the block over at least the greater part of the width of the block.

Preferably, the drainage conduit communicates with at least one opening in the lower surface of the block. More preferably, the drainage conduit communicates with a plurality of openings in the lower surface of the block and with openings in the upper sur- face which align, in use, with the openings in the lower surface of another of the blocks engaging the upper surface of the block. The openings in the lower surface of the block may be provided in shaped mouldings extending from said surface and engageable with recessed openings in the upper surface of another of the blocks.

Preferably, the lower surface has a pair of second connecting formations thereon, each second connecting formation being dimensioned and arranged to co-operate with one of said first connecting formations on another block.

Each first connecting formation preferably comprises a protuberance, and the or each second connecting formation comprises a recess. The protuberance may be of any suitable cross-section, for example circular or rectangular, the recesses being shaped and dimensioned so as to receive the protuberances and make contact sufficiently to hold the blocks together. More preferably, the protuberances are interference fits with the re- cesses so that, once the blocks are pushed, or if necessary tapped with a mallet, together, they are held firmly and resist separation. The use of adhesive between the blocks is thus unnecessary.

The blocks are preferably formed of a rigid plastics material such as unplasticised poly(vinyl chloride), a material conventionally used for window and door frames and doors. The plastics material may incorporate an inert filler and fire retardant. Dyes or pigments may be incorporated into the plastics material to provide a self-coloured building structure which will not require painting. The blocks can also be provided with a decorative coating or mouldings on the face which forms the external surface of the building, for example to simulate the appearance and/or texture of conventional bricks. The appear- ance of mortar beds between the blocks may also be provided for in the moulding. These may permit closer contact between adjacent blocks than would be allowed by a textured main surface, and thus act to minimise the gaps between adjacent blocks, It will be appre- ciated that it will be necessary to provide special blocks for finishing external corners of a building, for example half-length blocks or one-and- a-half-length blocks, having, where appropriate, the decorative coating or mouldings on one end face.

The blocks are preferably designed so as to be substantially hollow, whereby the enclosed air space affords thermal insulation and the weight of the blocks is minimised.

However, insulating materials such as expanded plastics or mineral wool may be incorpo- rated into the blocks, if required to improve the thermal insulation properties of struc- tures built from the blocks. The blocks may be dimensioned so as to ensure that sufficient insulation is achieved in a single skin of the blocks.

It is envisaged that specially-configured capping blocks will provide a wall plate to receive joists and rafters for a ceiling and roof to the building, with such blocks having only the second connecting formations therein. Means may be provided for anchoring the lowermost row of blocks to the building foundations. Lintels may also be formed, from plastics materials or from metal, with connecting formations at the ends thereof to enable them to be easily incorporated into the structure without the need for mortar or special constructional skills.

In one embodiment, the drainage conduit has an opening in the front face of the block and the connecting formations can, if necessary, be configured so that the blocks all fit together in the same way so that the drainage openings are all in the external surface.

Preferably, the upper and lower surfaces of the blocks each comprise at least a portion which lies at an acute angle to the horizontal so as to slope downwardly towards the external face of the building, so that moisture cannot penetrate inwardly through the horizontal joints between the blocks.

The blocks of the present invention permit buildings to be constructed quickly and simply by relatively unskilled workers. The blocks can be made substantially lighter than conventional solid building blocks, making them easier to transport and to use, permitting safe, dry and well- insulated shelter to be rapidly transported and assembled in disaster areas, for example. The lightness of the blocks and their method of assembly makes the resultant buildings safer for use in earthquake zones.

Brief Description of the Drawings

1 5 In the drawings, which illustrate exemplary embodiments of the blocks of the in- vention: Figure 1 is a perspective view of a block according to a first embodiment of the in- vention; Figure 2 is an underneath plan view of the block of Figure 1; Figure 3 is a front elevation of four blocks according to Figures 1 and 2, assembled together to form a portion of a building wall; Figure 4 is a front elevation of a block according to a second embodiment of the invention; Figure 5 is an underneath plan view of the block of Figure 4; Figure 6 is a sectional view on line A-A in Figure 5; and Figure 7 is a perspective view from below and to one side of the block of Figures 4 to 6.

Detailed Description of the Illustrated Embodiment

Referring first to Figures 1 to 3, the block 1 is generally rectangular in plan and elevation and is formed from a plastics material by injection moulding. Two connecting formations 2 protrude from the upper face 3 of the block, each consisting of a generally rectangular plug, and the two formations 2 being spaced apart from each other. The up- per face 3 of the block consists generally of a truncated pyramid shape providing surfaces which slope upwardly from the edges of the block, and from the centre, towards the formations 2.

In the lower face 4 of the block, as may be seen from Figure 2, two openings 5 are provided corresponding in shape, size and position to the formations 2 in the upper face, so as to be able to receive respective formations 2 from another block 1 when the blocks are stacked in a vertically_overlapping arrangement, as illustrated in Figure 3. The openings 5 extend inwardly of the blocks to provide hollow spaces within the blocks serv- ing to enhance the thermal insulation properties of the blocks. The openings are sur- rounded by sloping internal surfaces corresponding to the truncated pyramidal surfaces on the upper surface 3 so that inward migration of moisture through the horizontal joins between blocks is prevented. The formations 2 are a close fIt, preferably an interference fit, with the openings 5 so as to bind the blocks together to provide a semi-permanent In the arrangement shown in Figure 3, which is conventionally adopted when lay- ing bricks or blocks, to bond the bricks together, each vertical joint 6 between adjacent blocks 1 consists of smooth end faces of the blocks in close proximity. While the preci- sion of injection moulding techniques means that any gap between the faces can be kept very small, there is a risk of ingress of rainwater falling on the external face of a wall built from such blocks. This seepage of water, possibly by capillary action, will introduce the possibility of damp on the inner face of the wall, particularly at the lower part of the wall as the water seeps inwardly and downwardly. Seepage of water through the horizontal joints is much less likely, and over most of the length of the block will be substantially pre- vented by the interconnection of the formations 2 and the openings 4. In order to mini- mise the likelihood of water reaching the inner face of the building wall, the blocks are each provided with an internal drain 7. This comprises an opening 8 in the upper face of each block, arranged centrally between the formations 2 and extending over the greater part of the width of the block. The opening 8 leads to a chamber 9 within the block, hay- ing a lowermost surface 10 which slopes downwardly and outwardly towards an opening 11 in the front face of the block so that any water entering the chamber 9 is discharged to the exterior of the building. The moulding of the drain feature in the block would require at least one mould component which is withdrawn from the mould to permit removal of the finished block; such techniques are well-known in the injection moulding art.

Referring now to Figures 4 to 7, an alternative embodiment of the block is shaped so as to minimise the quantity of plastics material required to shape it, and to provide through drainage of moisture to a lower row of blocks, for example those connected to the foundations, where provision is made for discharge of the moisture externally of the building of which the blocks form a part. The block is substantially rectangular in form and has opposed pairs of side and end walls 40 and 41, the side walls 40 being joined to- gether centrally by an internal wall 42. The lower face 43 of the block consists of a pair of square openings 44 each surrounded by a frame consisting of a flat lowermost surface with chamfered sides 46. The surface 45 is provided with a plurality of through drain- age holes 47 uniformly spaced around it. A square-section tubular formation 48 extends 1 5 from each of the frames upwards through the block leaving an annular space 49 sur- rounding the formation which serves as an internal drain conducting moisture down- wardly to the drainage holes 47. The upper part 50 of each formation 48 has a reduced external cross-section with a shoulder 51 sloping inwardly and upwardly to define, with corresponding shoulders on the external walls 40 and 41 and on the internal wall 42 a tapered annular recess to receive the frames surrounding openings 44 in blocks located in the next row of blocks above, when constructing a building. In addition, the upper part of the formation 48 is received in a correspondingly stepped internal portion of forma- tion surrounding the opening 44 in a block fitting thereon. In this manner, any moisture penetrating into the vertical joint between two adjacent blocks in a wall will tend to drain downwardly until it reaches the top of the internal wall 42 which, being a peak between two chamfered edges, causes the moisture to run into one or both of the drain spaces 49 and then downward through the drainage holes 47 into the next block, and so on until the lowermost drainage course of blocks is reached. These may be provided with outlets discharging the moisture outside the building. Alternatively, fixings may be provided on the foundations to receive the first row of blocks and channel the moisture outwardly of the building. The various surfaces of the blocks are moulded in such a manner as to allow a close fit of one block on another, whereby the resulting structure has adequate stability without the need for any adhesive or fixing between the blocks.

Claims

1. A building block moulded in a plastics material and comprising an upper surface with a pair of first connecting formations thereon, a lower surface having a second connecting formation thereon, the first connecting formations on one block being adapted to co-operate with the second connecting formations on two other blocks to connect and hold the blocks together in a vertical overlapping arrangement, the sides of the blocks be- ing planar so as to rest in close engagement when the blocks are connected together side- by-side, each block having therein a drainage conduit arranged to conduct moisture through the block and discharge it from a lower part thereof, the drainage conduit having a central opening in the upper surface of the block over at least the greater part of the width of the block.

2. A building block according to Claim 1, wherein the drainage conduit communicates with at least one opening in the lower surface of the block.

3. A building block according to Claim 2, wherein the drainage conduit communicates with a plurality of openings in the lower surface of the block and with openings in the upper surface which align, in use, with the openings in the lower surface of another of the blocks engaging the upper surface of the block.

4. A building block according to Claim 4, wherein the openings in the lower surface of the block are provided in shaped mouldings extending from said surface and engageable with recessed openings in the upper surface of another of the blocks.

5. A building block according to any preceding claim, wherein the lower sur- face has a pair of second connecting formations thereon, each second connecting forma- tion being dimensioned and arranged to co-operate with one of said first connecting for- mations on another block.

6. A building block according to any preceding claim, wherein each first con- necting formation comprises a protuberance, and the or each second connecting forma- tion comprises a recess.

7. A building block according to Claim 6, wherein each first formation is an interference fit in a second connecting formation of another block.

8. A building block according to any preceding claim, wherein the upper and lower surfaces each comprise at least a portion which lies at an acute angle to the hori- zontal so as to slope downwardly towards the external face of the building

9. A building block according to any preceding claim, wherein the plastics ma- terial includes an inert filler material.

10. A building block according to any preceding claim, wherein the plastics ma- terial comprises a fire retardant.

11. A building block, substantially as described with reference to, and/or as shown in, Figures 1 to 3 or Figures 4 to 7 of the drawings.

12. A building having at least one part of a wall thereof constructed from a plurality of blocks according to any preceding claim.