Non-Corrosive Form Setting Stake and Permanent Leak-Proof Vapor Barrier Plugging Method

This application is a continuation of U.S. Ser. No. 16/173,591, filed Oct. 29, 2018, which is a continuation of U.S. Ser. No. 11/182,971, filed Jul. 16, 2005, each of which are herein incorporated by reference in their entirety.

The invention generally concerns improvements in the practice of slab on grade form setting. In particular, the present invention is a non-corrosive stake used for securing forms and a method of using the stake in cases where soil conditions are such that a permanent leak-proof vapor barrier is required to prevent potentially harmful elements in the soil from escaping and injuring anything or anyone above the barrier.

In slab on grade foundations, forms are necessary to hold the concrete in place while it dries and hardens. The forms themselves are held in place by strategically locating wooden or steel stakes. When the form setting stakes are removed, they create holes in the vapor barrier. Normally these holes are not of great concern. However, there are a growing number of soil conditions in which holes in the vapor barrier can cause problems. For instance, in cases where the soils below the foundation contain elements that corrode concrete (e.g. acid, sulfites, chlorides, nitrates, nitrites) or contain potentially harmful gases (e.g. radon or methane), or contain excessive amounts of water vapor that can cause mold or ruin things inside the structure such as wooden floors. In addition, homes today are now being built on land previously considered unsuitable for housing, such as old landfills, abandoned oil fields, and old industrial sites. In these types of situations the vapor barrier cannot have holes because these elements can leak through the holes and cause not only financial loss but physical ailments that can even potentially be life threatening.

In view of the foregoing, therefore, a need exists for a form setting stake that permanently prevents leaks through the vapor barrier. Ideally this stake must also be light weight, durable, easy to manufacture, capable of conforming to various form sizes, simple to use, and comprised of few parts.

A wide variety of stakes and methods of securing stakes to form boards exist. Examples of such stakes and methods are shown in U.S. Pat. No. 6,705,582 B2 (Osborn, 2004), U.S. Pat. No. 6,021,994 (Shartzer, Jr., 2000), U.S. Pat. No. 5,830,378 (Butler, 1998), U.S. Pat. No. 5,230,187 (Reimann, 1993), U.S. Pat. No. 5,076,536 (Fitzgerald, 1991), U.S. Pat. No. 4,776,555 (Maynard, 1988), U.S. Pat. No. 4,723,752 (Thomas, 1988), U.S. Pat. No. 4,635,895 (Johnson, Jr. et. al., 1987), U.S. Pat. No. 4,533,112 (Santos, 1985), U.S. Pat. No. 3,785,606 (Green, 1974), U.S. Pat. No. 3,378,968 (Shoemaker, 1968), U.S. Pat. No. 3,300,920 (Skaare, 1967), U.S. Pat. No. 2,846,749 (Yates et. al, 1958), U.S. Pat. No. 2,741,821 (Findley, 1956), U.S. Pat. No. 1,897,530 (Pandolfi, 1933), U.S. Pat. No. 1,741,829 (Cucolo, 1929), U.S. Pat. No. 1,607,690 (Rue, 1926), U.S. Pat. No. 1,512,165 (Funkhouser, 1924), U.S. Pat. No. 1,382,082 (Heltzel, 1921). While much prior art can be found in the field of slab foundations and related concrete work, the commercial success of the stakes and methods is limited. The primary reasons for this are that these ideas tend cither to be expensive, complicated, and/or inflexible. In addition, and most important, all of the above mentioned inventions create holes in the vapor barrier, and none even address the issue of leakage, let alone putting an end to leakage through the vapor barrier.

The area of form setting is extremely resistant to change, and despite the inventions proposed above, the vast majority of slabs continue to be set with standard wooden boards and stakes. Similarly the concern for vapor barrier leakage has been handled through the use of common construction materials, and nothing is currently in use that has been specifically designed to address this issue.

In the field of slab foundations there are several methods currently in use to help prevent leakage through the vapor barrier. However each method has its own set of problems. One of the oldest methods uses common steel dowels to hold the forms. The vapor barrier is then sealed to the dowels. Before the concrete is cured, the dowels are cut off just below the concrete's surface. The concrete is then finished, completely covering the remaining portion of the dowels. Because the dowels are permanently left in place, the holes made in the vapor barrier are temporarily plugged. However, the reality is that, over time, the steel dowels will eventually corrode, thus again leaving holes in the vapor barrier that leak. Because this is only a temporary solution to the problem of vapor barrier leakage, many inspecting agencies today are no longer allowing construction companies to use this method.

A second method involves suspending the forms from above, using beams supported by stakes that are driven into the ground outside the vapor barrier, thus avoiding all types of penetration through the vapor barrier. This method is not widely used, however, because it is time consuming and has only proven to be barely effective in the creation of small foundations that can be easily spanned. In the case of large foundations, the distance that must be spanned in order to support the forms from above, is too great. Or conversely, systems that are engineered to span great distances are too costly and unmanageable. Even in cases where this method is used, the finished product is often below building industry standards.

A third method involves taking a two to three foot section of polyvinyl chloride (PVC) pipe with a PVC cap glued to one end. A hole is dug and the PVC pipe is placed with the capped end facing down into the hole. The pipe is plumbed and secured in place by compressing the earth around it. Several inches of the pipe are left exposed above the earth and the vapor barrier is scaled around the exposed pipe, similar to a plumber's pipe penetration. A wooden dowel is wedged into the pipe and protrudes above the pipe high enough to accommodate the forms. This process is repeated approximately every two feet on center at which point forms are held in place by being nailed to the dowels. Before the concrete is cured, the wooden dowels are removed from the PVC pipe. The PVC pipe is left in place below the surface of the concrete and the concrete is finished. Although this method leaves the vapor barrier intact, it is time consuming, labor intensive, and, thus, costly.

A fourth method involves driving a stake or dowel into the ground. A small section of PVC pipe is then slid over the stake or dowel, and rests on the ground. This process is repeated approximately every two feet on center at which point forms are then nailed in place to the stakes. The vapor barrier is sealed around the pipes, again similar to a plumber's pipe penetration. The concrete is poured. Before the concrete is cured, the stakes or dowels are removed from the PVC pipes. A cap is glued in place over each exposed PVC pipe, but below the finished concrete surface. The concrete is then finished and completely covers the PVC pipes and caps. One of the main problems with this method, however, has to do with the timing of inspections. Before pouring the concrete and gluing the caps in place, each job must pass inspection. Inspections typically occur several days before the concrete pour, thus allowing enough time to schedule the arrival of the concrete. After giving their approval to pour the concrete, inspectors are assuming and hoping that the caps are glued in place after the stakes or dowels have been removed and before the concrete is finished. However, other than breaking through the concrete to check, there is no real way to confirm that the caps have been properly installed, if installed at all. And, without the caps properly in place, the vapor barrier has been breached.

The difficulties encountered in the prior art are substantially eliminated by the present invention.

Accordingly, besides the objects and advantages of the non-corrosive stake for form setting described above, several objects and advantages of the present invention are:

Further objects and advantages are to provide a stake for form setting which is strong enough to hold the forms yet lightweight enough to easily handle and carry, which is similar enough to what is already used in the field so that crews will not have to be extensively trained or have to learn any new techniques, which is made of a single piece of non-corrosive material that does not require any additional pieces and can be used with all other materials currently in use, which is less time consuming to use, and which can accommodate forms of different sizes.

Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.

In accordance with the present invention, a non-corrosive stake for form setting a slab on grade foundation when a vapor barrier is required comprising an elongated body, a leading end adapted for piercing the earth, a trailing end that serves as a striking surface for driving the stake into the earth, a way of securing a form board to the stake, and a permanent leak-proof plugging method that prevents elements in the soil from escaping through the vapor barrier.

In the drawings, closely related figures have the same number but different alphabetic suffixes.

Reference is now made to(overall perspective), wherein the stakeis in the shape of a cylinder. The cylindrical form is preferred because it is smooth and has rounded edges, thus facilitating the stake's ability to adhere to the vapor barrier and minimizing the possibility of leaks. The cylindrical form also takes advantage of existing sealing methods already proven to be effective in plumbing penetrations. Thus, the cylindrical form is easier to work with and more cost effective.

In the preferred embodiment the stakeis made of a sturdy solid plastic. The stake is solid so as to reduce the possibility of leaks through the stake itself and in order to increase the stake's strength and rigidity. And, in the preferred embodiment, the stake will be made of plastic, because it is currently the most cost effective non-corrosive material available.

In the preferred embodiment the overall length of the stake is one meter with a diameter of 2 centimeters. In essence, the stake is long enough to accommodate the majority of building conditions and thick enough to endure the force of concrete. However, to accommodate less common building conditions, the stake may vary in length and diameter. It is very possible, for instance, that a viable secondary market may exist for another stake that is approximately 125 cm in length and 2.5 cm in diameter.

At the leading end of the stake, and as best viewed in, is a pointadapted to penetrate the ground. In the preferred embodiment, the point is wedge-shaped thus helping to prevent the stake from twisting into the earth and keeping the holes in the stakeperpendicular to the form board. Holes that are perpendicular to the form board, in turn, will increase the case of driving nails through the stake and into the form board.

In the preferred embodiment, and as best viewed in, six holesrun through the width of the stake. In the preferred embodiment, the first hole is located 2.5 cm from the trailing end of the stake and consecutive holes are located every 3.5 cm on center for the remaining five holes. If needed, additional holes, or differently located holes, may be provided to accommodate various forming conditions.

In the preferred embodiment, the holeswill have a diameter large enough to accommodate aduplex nail. Although the present invention may be held securely in place in a variety of ways, in the preferred embodiment the temporary form is secured with duplex nails, because duplex nails are current industry standard and are easy to remove.

On the trailing end of the stake, and as best viewed in, is the stake head. In the preferred embodiment, the stake head is cut perpendicular to the shaft of the stake. The trailing end serves as a striking surface for driving the stake into the ground.

are perspectives of the non-corrosive stake as it is to be used in the construction of a slab on grade foundation when a leak proof vapor barrier is required to prevent potentially harmful elements in the soil from escaping and injuring anything or anyone above the barrier.

shows the present invention as it is being used to support a form board during the forming of a depression in the slab on grade foundation. In this figure, two stakeshold the temporary formsecurely in place. One stake is perpendicular to the form board and the other rests at approximately a 45 degree angle. The stakespenetrate the vapor barrier, its protective sand layers, and are driven into the earth. In the preferred embodiment, the temporary form is secured with duplex nails. As seen in, the duplex nails run through the holesin the stake. This process is repeated with a plurality of stakes until all form boards required for a particular project are supported.

As shown in, a permanent sealis created around each staketo the vapor barrier. The sealis the same seal currently being used around plumber's pipe penetrations, thus does not require additional training, equipment, or engineering; it has been proven to resist leaks and is cost effective. Once the stakesare sealed, each stake acts as a plug in the vapor barrier that prevents elements in the earth from escaping through or around the stakes. After the stakeshave been sealed, the vapor barrieris inspected by the appropriate governing agencies for leaks. Once approved by the inspector, concrete can be ordered and a labor force can be scheduled to place the concrete. At this point, no further inspections are required to ensure the consumer that a leak proof vapor barrier has been provided.

shows the present invention in its final state with a portion of the stake left permanently embedded in the earth and finished concrete. In this figure, a portion of each stakehas been cut roughly 2.5 cm above the stake's sealed portion. After the project passes inspection, the forms (see) are no longer needed because they have performed their job. The forms are then removed and the top section of each stakeis cut off above the stake's sealed portionbut below the slab's finished surface. The concrete foundationis then finished. As shown inthe lower portion of each stakeis left permanently embedded in the earthand finished concrete, thus the lower portion of each stakeacts as a permanently plug in the vapor barrier, ensuring a long term solution to leaking.

This process creates a foundation that is aesthetically acceptable to the consumer while providing a permanent leak-proof plug in a cost effective manner. The process is also timed to meet industry standard inspection requirements, so that, the consumer is assured of a long term, non-corrosive, solution to leakage. In addition, the process is simple, and is less time consuming than other methods currently in use. And most important, this method keeps potentially harmful elements in the soil below the vapor barrier and away from objects and individuals residing above the vapor barrier.

Although the description above contains many specifications, these should not be construed as limiting the scope of the invention but merely providing illustrations of some of the presently preferred embodiments of this invention. For example, the stake can be made in a variety of other shapes, such as oval, square, triangular, etc., or even made of a combination of shapes, such as square at the trailing end and cylindrical at the leading end.

The stake can be made of a variety of non-corrosive materials other than plastic, such as stainless steel or even titanium. The stake can be made in a variety of lengths and in other diameters to accommodate a variety of construction demands. In addition, the stake could have a variety of leading ends differently adapted to penetrate the earth (e.g. a pointed end, or tapered wedge-shape, etc.), or be made with a variety of trailing ends differently adapted to act as a striking surface (e.g. a trailing end with a wider or rounded striking surface, etc.). The stake might be made with a different number of holes, differently sized holes, or holes that are differently located on the stake. Moreover, the stake can be secured to the temporary forms with a variety of other fasteners (e.g. screws, or u-nails) or in a completely different manner than the one described in the preferred embodiment. And finally, a wide variety of sealants and methods of sealing may be used to seal the stake to the vapor barrier.

Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.