Patent Application
20090120027
The present invention relates to forms for concrete walls, and more particularly to ties for connecting and maintaining first and second panels of a concrete formwork in a fixed, spaced relationship during a wall building process.
Conventional formwork for forming walls from pourable building material such as concrete consist of two opposed, typically plywood walls connected by a rod, trusswork or other connecting structure. More recently, it has become desirable to use insulating material such as expandable polystyrene for the formwork, in order to provide thermal and acoustic insulation to the finished wall. In certain applications, particularly those where it is desired to inhibit the effects of “thermal inertia” of a concrete wall so as to employ the ability of the concrete to retain heat for temperature stabilization, it is desirable to employ formwork with insulated paneling on only one side. The other side, typically of plywood, may or may not be removed after full or at least partial curing of die concrete.
Various insulated formworks and related technologies have been considered. For example, U.S. Pat. No. 5,845,445 to Blackbeard discloses an insulated concrete form with a plurality of plywood boards at an inside surface, and a plurality of insulating foam panels at an outside surface. The plywood boards and insulating foam panels are connected by a plurality of elongated vertically aligned connecting members for retaining the panels in a spaced apart parallel relationship during the wall building process. The connecting members are connected to the insulating panels, and ties are attached to respective connecting members and the plywood boards. Each tie has a conventional embossed end to engage into a latch clip on the plywood side. During de-forming, the plywood boards may be removed by removing the attachment between the ties and latch clips.
U.S. Pat. No. 6,314,694 to Cooper et al. discloses a one-side insulated formwork that includes an insulating panel connectable to a removable panel by a connecting structure, which may provide permanent reinforcement embedded in the insulating panel. The removable panel is attached to the connecting structure using removable fasteners. The connecting structure maintains a fixed spaced relationship between the insulating panel and the removable panel, and according to embodiments disclosed includes rebar hooks for supporting rebar for embedding in the concrete. After the concrete has at least partially cured, the removable fasteners and removable panel are removed, leaving exposed and flush with the outer surface of the concrete wall a surface of the connecting structure suitable for flush connection of a finishing panel.
U.S. Pat. No. 6,526,713 to Moore, Jr. discloses an insulated concrete structure for forming walls from a pourable building material such as concrete. Moore proposed connecting two panels of a formwork using a web structure, a portion of which is preferably embedded in an insulating one of the panels. After the concrete has at least partially cured, one of the panels being now adjacent to the formed wall, may be removed or remain as part of the structure.
Although the above references disclose insulated formwork of various configurations, improvements are desired. For example, none of the references discussed above consider the challenges of installing electrical and/or plumbing after or during the wall forming process. It is therefore an object of the present invention to provide a novel wall form, tie and method using the same for building walls from pourable building material, such as concrete.
According to an aspect, there is provided a tie for connecting and maintaining first and second panels of a concrete formwork in a fixed, spaced relationship during a wall building process, the tie comprising:
a first connector connectable to the first panel; and
a second connector connectable to the second panel and connectable to at least one third panel such that the at least one third panel is spaced from the concrete surface.
According to an embodiment, the second panel is made of plywood and the third panel is made of drywall.
According to an embodiment, an insulating wall form comprises the tie, a first panel made from an insulating material and connected to the first connector; and a second panel connected to the second connector.
According to another aspect, there is provided a method of making a concrete wall, comprising:
providing a first panel having an inward facing surface and an outward facing surface, the first panel made of insulating material;
providing a second panel having an inward facing surface and an outward facing surface;
connecting a first connector of a tie to the first panel and a second connector of the tie to the second panel, wherein the first and second connectors are separated by an intermediate portion with a length corresponding approximately to the thickness of the concrete wall thereby providing a fixed space between the first and second panels for receiving a charge of the concrete; and
attaching a third panel to the second connector to provide a fixed space between the concrete surface and the third panel.
The tie, formwork employing the same, and method for making a wall provide previously unrealized advantages because they permit the option, of removal of the second panel after wall construction prior to attachment of the third panel, while permitting spacing between the third panel and the concrete surface and/or second panel for passing electrical wires and/or plumbing and the like. Thus, the electrical wires and/or plumbing may more easily be inspected and/or repaired than systems which involve embedding such utilities in, the concrete wall itself.
Embodiments will now be described more fully with reference to the accompanying drawings in which:
In the following description, embodiments of a tie for connecting and maintaining first and second panels of a formwork in a fixed, spaced relationship during a wall building process, and of a method of making a concrete wall are provided.
The tie 50 includes a first connector 52, an intermediate portion 60, and a second connector 54. As can be seen, the first connector 52 is embedded in the first panel 10. The second connector 54 is shown connected to the second panel 20 at a second panel connection portion 56 by screws or other suitable removable fasteners. The second connector 54 is removable from the second panel 20 upon removal of the fasteners. The tie 50 maintains the first and second panels in a fixed spaced relationship thereby to provide space between the panels for receiving and holding a charge of poured concrete 40.
The second connector 54 of the tie 50 also includes a third panel connection portion 58 that is spaced from the second panel connection portion 56 by virtue of the dimensions of the second connector 54 and the relative positions of the second and third panel connection portions 56, 58. More particularly, the second panel connection portion 56 and third panel connection portion 58 are spaced apart such that the third panel 30 when connected to the third panel connection portion 58 is spaced from the inside surface of the concrete wall 40. The use of this spacing is illustrated in
Multiple ties 50C are stackable by virtue of mechanical interlock members. These mechanical interlock members include respective stacking protrusions 66C on the second panel connection portion 56C and the third panel connection portion 58C. The stacking protrusions 66C mate in interference fit with respective corresponding stacking channels (not shown) in adjacent second and third panel connection portions 56C, 58C of an adjacent tic 50C.
At the bottom of
It can be seen in
In order to make a wall from pourable building material such as concrete, a first panel made of an insulating material is provided. The first panel has an inward facing surface facing towards the interior of the building, and an outward facing surface facing towards the exterior of the building. A second panel, also having an inward facing surface and an outward facing surface, and preferably of plywood, is also provided. The first connector of the tie is connected to the first panel. It will be understood that this may be done upon manufacture of the first panel where the insulating material is expandable polystyrene or the like such that the first connector is thereby embedded in the panel during moulding. The second connector of the tie is then connected to the second panel using fasteners such as screws and/or some alternative or combined mechanical connection. When the first and second panels are connected to the tie as described, the first and second connectors are separated by an intermediate portion with a length corresponding approximately to the thickness of a wall being made. A fixed space between die first and second panels for receiving a charge of the concrete is thereby provided. A charge of concrete is then provided into the fixed space between the first and second panels. The electrical cable and/or plumbing may be passed through passageways 62 prior to connection of the third panel, preferably made of drywall.
It will be understood that, in some embodiments, the third panel may be connected prior to pouring of the concrete into the fixed space between the second and third panels. If electrical cable and/or plumbing are required, then this of course is installed prior to connection of the third panels. In some cases, the second panels would remain part of the finished wall, albeit hidden from view inside the building by the third panels. Furthermore, the second panels may remain part of the finished wall whether or not the third panels were connected prior to or after pouring of the concrete. This is left to the preference of the builder, and the suitability of the second panel remaining part of the wall. Indeed, some described embodiments of ties described herein require removal of the second panel prior to connection of the third panel, and some do not.
Depending particularly upon the required height of the concrete wall being built, first and second panels may be vertically stacked upon each other to provide a formwork having a suitable height.
Embodiments of ties have been shown for use in construction environments in which a second panel is desired to be disconnected from the tie prior to connection of a third panel, and also in which the second panel may remain while a third panel is being connected.
While embodiments have been shown hereby ties are stacked using a mechanical interlock mechanism, other configurations are possible. For example, second connectors of two adjacent ties may cooperate with each other to connect to second and/or third panels without interlocking. In such an embodiment, two second connectors of two ties may have second panel connection portions that do not mechanically interlock or even touch, but align to both receive a common second panel. In other or complementary embodiments, the first portion of a tie may span the entire height of a first panel, while intermediate portions and/or second portions do not. Various combinations and modifications within the scope of the invention are possible.
While embodiments have been shown that have the third panel spaced from the second panel, it will, be understood that second panels may be provided that are dimensioned and configured with respect to a tie so that there is little or no space between the third and second panels. It will be understood that in such embodiments, the second panel is intended to be disconnected from the formwork prior to connection of a third panel, such that the third panel is in fact spaced from the concrete wall surface thereby permitting passage of electrical cables/plumbing and the like between the third panel and the concrete wall surface.
Although embodiments have been described, those of skill in the art will appreciate that variations and modifications may be made without departing from the spirit and scope thereof. As defined by the appended claims.
