This invention relates to apparatus for use in the construction of a concrete floor system or foundation for a building, a footing for a building and a method of construction thereof.
It is common for the foundation of a building to be formed primarily out of poured concrete.
The footings of a foundation are those parts of the foundation which will be underneath the load-bearing walls of the finished building, and therefore will carry the most weight. It is therefore usual for the footings of the foundation to be thicker than the main part of the foundation.
A complete concrete floor system incorporates both footings and a slab which together form the foundation for the building. This concrete floor system may be coated with a lining material such as vinyl, tiles or carpet, painted or left untreated (depending on the desired use) to provide a finished floor for the ground floor of the building.
The standard practice to prepare a site for the laying of a foundation is to remove the top soil so that the slab will rest on the harder substrate below. The paths of the footings are then dug as trenches deeper into the substrate.
The slab site may then be lined with a damp-proof membrane. It is known to place thin sheets of polystyrene across the flat areas under the main part of the foundation in order to provide a flat smooth surface with good insulating properties on which the concrete foundation can be poured.
In order to form the mould into which the concrete will be poured, wooden planks are used to form boxing around the edges of the footing trenches. These planks must be properly aligned to contain the fluid concrete and are pegged into position to withstand the weight of the concrete.
Once the boxing has been completed, standard metal reinforcing is placed in the footing trenches. The concrete is then poured into the mould. Once the concrete has cured sufficiently to be self-supporting, the wooden boxing is removed.
This industry-standard method is labour-intensive, both in setting up and in removing the mould. The resulting foundation may be insulated under the main part of the slab, but not under the footings, and the sides of the foundation which are above ground level are unsightly, rough concrete.
It is an object of the present invention to provide at least one of the following:
The present invention comprises a moulding for a foundation footing, including:
said sections being connected together to present a substantially u-shaped cross-section and wherein the first wall section is taller than the second wall section.
The present invention further comprises a foundation footing, including:
The present invention further includes a concrete floor system or foundation including:
Preferably the moulding is made of polystyrene. Preferably the moulding is self-supporting.
The moulding may also include an outer coating on the first wall section, selected from the list comprising: cement sheet, smooth plaster finish, texture coating.
The present invention yet further comprises a method of forming a concrete floor system for a building, including the steps of:
The method may further include the step laying sheets of polystyrene, or some other thermally insulating material, across the main part of the mould. Preferably the bottom of the moulding is on substantially the same level as the bottom of the thermally insulating sheets.
By way of example only, a preferred embodiment of the present invention is described in detail with reference to the accompanying drawings, in which:
Referring to
First wall 2 is taller than second wall 3 and has a layer of outer coating 5 on its exterior side. The outer coating may preferably be a texture coating. This outer coating 5 forms the exterior of the finished foundation, and can then be painted to match the exterior of the building, without the need for any further treatment, to produce an aesthetically pleasing result.
The moulding 1 can be extruded in pre-cut lengths, or custom-made to match the dimensions of a specific job, either on-site or off-site. The moulding 1 is not limited to straight lengths, but can be manufactured as a curved length.
In order to achieve a desired length of moulding 1, multiple pre-cut lengths can be placed adjacent to each other, and optionally secured together by glue or other known means. Pre-cut lengths of moulding 1 can also be cut down where a shorter length is desired.
Referring to
The moulding 1 is placed in position for the footings, and known reinforcing stirrups 8 are placed on known reinforcing chairs in each moulding 1, along with longitudinal reinforcing rods 11. There is no need to use pegs to hold up the moulding 1, which is self-supporting. However, on some sites it may be desirable to place some pegs against the moulding 1 to hold it in place, prop or brace it. The main part of the slab site between the footings is lined with polystyrene sheets 9 to form a continuous polystyrene mould. The bottom of the moulding 1 is on substantially the same level as the bottom of the polystyrene sheets 9. Alternatively, ordinary fill can be substituted for the polystyrene sheets 9. If the building requires piles, holes can be cut in the moulding 1 to accommodate the piles.
Concrete 10 is then poured into the mould in a continuous pour across the main floor of the foundation and through the footings to complete the foundation. Once the concrete 10 is cured, the concrete floor system is complete. The mould forms part of the finished foundation, and does not need to be removed.
In an alternative embodiment (not shown), first wall 2 is the same height as second wall 3 and has no texture-coating. This embodiment is suitable for footings situated within the main part of the slab, rather than at the exterior of the foundation.
In another embodiment, the slab site preparation may include digging trenches for the footings, and the moulding 1 may be placed within these trenches.
It will be apparent to one skilled in the art that a foundation footing according to the present invention results in a foundation which is thermally insulated not only under the main floor, but also throughout the footing and under the walls, which provides an advantage over existing systems, which do not provide any thermal insulation under the walls of the building.
Number | Date | Country | Kind |
---|---|---|---|
542068 | Oct 2005 | NZ | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/NZ2006/000267 | 10/19/2006 | WO | 00 | 6/16/2008 |