EP0020014B1

EP0020014B1 - Building elements and method of constructing a building

Info

Publication number: EP0020014B1
Application number: EP80301291A
Authority: EP
Inventors: Gordon Macdonald Robertson
Original assignee: ROBERTSON'S BUILDING SYSTEM (PvT) Ltd
Current assignee: ROBERTSON'S BUILDING SYSTEM (PvT) Ltd
Priority date: 1979-04-27
Filing date: 1980-04-22
Publication date: 1983-10-05
Also published as: EP0020014A3; DE3065129D1; EP0020014A2; ZA802528B

Description

This invention relates to building elements and to a method of constructing a building employing said elements.
At present, in many cases, the walls of buildings are constructed either of bricks or of concrete appropriately restrained during setting by shuttering. In both these cases skilled labour is equired either to lay the bricks or to assemble the shuttering. Moreover, once the walls have been built the inside surfaces still need to be plastered to produce the desired interior finish.
A proposal providing a cavity between the inner and outer wall surfaces is disclosed in DE-U-1899117 where inner and outer blocks are connected together at aligned joints. However, in that arrangement there is no lateral restraint or connection between adjacent blocks. Another such proposal is shown in U.S.-A-1421278 where inner and outer blocks are positioned together to form cavity walling. Reinforcing ties project into the cavity and may be secured to a vertical reinforcing rod by manipulation within the cavity.
According to the present invention there is provided a building unit comprising two moulded portions having confronting inner surfaces, one or more rebates being formed along each of two opposite side edges of each portion and opening onto the outer surface of the respective portion, characterised in that connecting means are embedded in each portion and project into the said rebates along the side edges of the portions, the connection means of a first building unit being interconnectable with the connection means of a second building unit to connect the two building units together.
The walls of a building are constructed with a building panel consisting of two such portions or building sheets spaced apart by suitable spacing means. Such a panel forms high quality permanent shuttering for a core material, the outer surfaces of the sheets producing the desired inner and outer surfaces without the need for further plastering or finishing. Thus, the use of a building panel in accordance with the invention enables walling to be produced with unskilled labour.
According to another aspect of the invention there is provided a moulded building sheet adapted to be assembled in spaced apart relation with another similar sheet to form a cavity wall wherein the sheet has inner and outer surfaces with two opposite side edges, a rebate being formed in each side edge at the corner where the side edge meets the outer surface of the sheet, characterised in that reinforcing wires project from each of the rebates along the side edges of the sheet whereby when two similar sheets are assembled in side by side relation with their rebates facing outwardly the wires projecting from the other sheet.
The invention also includes a method of constructing the walls of a building from moulded building sheets comprising the steps of providing a plurality of building panels by interconnecting the inner surfaces of pairs of building sheets with spacing means, placing the panels in relative juxtaposition so that their side edges are abutting, and twisting together the outwardly facing reinforcing wires projecting into the rebates of one panel with the outwardly facing reinforcing wires projecting into the rebates of an adjacent panel to join adjacent panels to one another.
In order to produce solid walling the method includes the additional step of filling the space between the spaced sheets of the panels with core material.
The invention will now be described by way of example with reference to the accompanying drawings in which:

Figure 1 is a plan view of a building panel comprising two moulded sheets or skins in accordance with the invention;
Figure 2 is a fragmentary plan view of the joint between two adjacent moulded sheets or skins;
Figures 3a and 3b illustrate in plan different types of wall junctions in a building incorporating panels in accordance with the invention;
Figure 4 is a perspective view of a junction between a panel and a window panel;
Figure 5 illustrates the preferred method of forming corners; and
Figure 6 is a sectional side elevation of a single-storey building constructed with panels in accordance with the invention.

In the drawings a preferred sheet 1 is moulded of cement based material and has inner and outer surfaces 2 and 3 defined by top and bottom edges 4 and side edges 5. The side edges 5 of the sheet 1 are of increased thickness and are moulded with a rebate 6 at the outer surface 3 of the sheet. The rebate 6 is of a width of about 20 mm and a depth approximately equal to the general thickness of the rest of the sheet. The thicker side edges 5, whilst accommodating the rebates 6, also provide structural stability at the edges. The sheet 1 is reinforced with laterally-extending reinforcing wires 7 which project into and beyond the rebates 6 at the side edges 5 of the sheet and which together with the rebates 6 form means for joining sheets together as explained below. The sheet 1 also includes loops 8 which project from the inner surface 2 of the sheet for a purpose also described more fully below. Preferably these loops 8 are formed by some of the reinforcing wires 7 being bent into a configuration which causes the loops 8 to project outside the plain of the sheet when it is being cast.
As seen in the drawings it is preferred that a building panel 10 consists of two spaced sheets 1, metal ties or spacers 11 being clipped in place between adjacent loops 8 projecting from the confronting inner surfaces of the respective sheets. In order to fix two panels together they are placed with their adjacent side edges 5 abutting one another. The projecting reinforcing wires 7 of the respective sheets are then twisted together in the manner illustrated in figure 2: this holds the wall panels in their relative positions. If a coner is to be formed then the inside sheets of the adjacent panels may be tied with the sheets straight and then the sheets 'folded' to the desired angle as shown in figure 5. Alternatively an inside and outside corner piece 12 or 13 may be used as illustrated in figures 3a and 3b.
When the panels 10 required to form a building have been placed in position and the joint wires are all tied together, the space between adjacent sheets can be filled with a suitable core material 14 such as concrete, "no fines" concrete, soil/cement or any other suitable strengthening or, alternatively, insulating material: the thicker side edges of the panels helping to resist any tendency of boxing at the joints between adjacent panels.
When the core material 14 has hardened the joint wires 7 are pushed into the groove 15, defined by two adjacent rebates 6, which is then filled with cement mortar which conceals the joint.
Figure 6 illustrates a building panel 10 in use where it is supported on a suitable foundation 16 and in turn supports a ceiling structure 17 and tiled roof 18. Although not shown, the ceiling structure may consist of single sheets supported from rafters 18. The flooring 19 suitably may be solid as shown and moulded panels for the windows and doors may be fitted as appropriate as indicated by the window panel 20 shown in figure 4.
In use the sheets 1 have the dual purpose of first forming shuttering for solid core material 14 and then forming internal decoration and external weather proofing.
The moulds for the sheets, having a size, shape and negative texture to that required of the finished sheet, contain a detachable perimeter frame/s which allow the reinforcing wires to be placed and held in position the required distance from the face of the mould. The wires are woven and pulled taut and the mix suitably cement mortar, i.e. a mixture of cement, sand and water, is poured into the mould to give the required thickness of skin. The whole mould is vibrated to cause the mixture to settle.
As indicated above the sheets can be moulded to form openings in the walls such as windows surrounds, reveals and frames or door architraves, reveals and frames. Water drips, weathering angles, sills, etc. can be incorporated in the moulding as can hinged recesses and locking device plates. The sheets can be moulded to form inside and outside corners at right/obtuse angles. The sheets can be moulded in the form of curves to produce a circular or compound curved wall plan. Also, although straight sheets have been disclosed, the sheets can be moulded to form walls the surface of which is an induced curve, e.g. an hyperbolic- perabaloid.
The surface of the sheet can have the texture produced by a suitably textured mould for example to simulate brickwork. The surface layer of the sheets may be coloured and include a waterproofing agent.
The sheets may be moulded to accommodate "services" such as electrical points, conduits, water and sewerage fittings, pipes, soap holders in bathrooms and kitchens etc. Although it is preferred to provide a single rebate along each side alternatively separate rebates associated with each reinforcing wire may be provided if desired.

Claims

1. A building unit (10, 20) comprising two moulded portions (1) having confronting inner surfaces (2), one or more rebates (6) being formed along each of two opposite side edges (5) of each portion (1) and opening onto the outer surface (3) of the respective portion (1), characterised in that connecting means (7) are embedded in each portion (1) and project into the said rebates (6) along the side edges (5) of the portions (1), the connecting means (7) of a first building unit (10, 20) being interconnectable with the connection means (7) of a second building unit to connect the two building units together.

2. A building unit according to Claim 1 characterised in that the unit (10) is a wall panel comprising two moulded sheets (1) having confronting inner surfaces (2) spaced apart by spacing means (8, 11).

3. A building unit according to Claim 1 wherein the unit (20) is a window or door panel with a frame section therefor moulded about an opening formed in each moulded portion.

4. A building unit according to Claim 1 characterised in that the connecting means (7) comprises reinforcing in the form of wires (7) which project into the rebates (6) along the side edges (5) of the portions (1), the reinforcing wires (7) of one unit (10, 20) being engageable with the wires (7) of another unit (10, 20) to joint the two units together.

5. A building unit according to Claim 2 characterised by the provision of a plurality of loops (8) which project from the confronting inner surface (2) of the sheets (1).

6. A building unit according to Claim 5 characterised in that the connecting means (7) comprises reinforcing in the form of wires (7) and the said reinforcing wires (7) are appropriately shaped to form said loops (8).

7. A building unit according to Claim 5 or 6 characterised in that the spacing means (8, 11) comprises ties (11) secured to loops (8) projecting from opposing faces of the moulded sheets.

8. A moulded building sheet adapted to be assembled in spaced apart relation with another similar sheet to form a cavity wall (10, 20) wherein the sheet has inner and outer surfaces with two opposite side edges, a rebate (6) being formed in each side edge (5) at the corner where the side edge (5) meets the outer surface (3) of the sheet (1) characterised in that that reinforcing wires (7) project from each of the rebates (6) along the side edges (5) of the sheet (1) whereby when two similar sheets (1) are assembled in side by side relation with their rebates (6) facing outwardly the wires (7) projecting from one sheet (1) may easily be connected to the wires (7) projecting from the other sheet (1).

9. A method of constructing the walls of a building from moulded building sheets according to Claim 8 comprising the steps of providing a plurality of building panels by interconnecting the inner surfaces of pairs of building sheets with spacing means, placing the panels in relative juxtaposition so that their side edges are abutting, and twisting together the outwardly facing reinforcing wires projecting into the rebates of one panel with the outwardly facing reinforcing wires projecting into the rebates of an adjacent panel to join adjacent panels to one another.

10. A method of constructing a building according to claim 9 characterised by the additional step of filling the space between the spaced sheets of the panels with core material to form solid walling.