Abstract:
An insulated concrete form system for receiving poured concrete to form a unitary, insulated concrete wall. A novel tie bracket, spaced on one foot centers, space the two sides of he forms apart from one another. The tie brackets extend fully from top to bottom of the forms, thereby providing increased structural strength to the formed wall and providing “studs” at regular intervals for the fastening of structural elements, such as paneling or sheetrock. A rebar attachment piece may be attached to the a rebar receptacle formed in the tie bracket such that rebar may be offset to either side of the poured wall, as necessary. The forms are in straight, corner and Tee configurations to aid in the quick laying of the forms and to provide increased strength to the formed wall. A combination of tongue and groove joints and interlocking protrusions and notches add further strength and integrity to the formed wall.

Description:
REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is a continuation in part of applications Ser. No. 09/932,096, FORM BRACING TIE BRACKET FOR MODULAR INSULATING CONCRETE FORM SYSTEM AND FORM USING THE SAME; Ser. No. 09/932,095, CORNER FORM FOR MODULAR INSULATING CONCRETE FORM SYSTEM, now U.S. Pat. No.______; and Ser. No. 09/932,081, MODIFIED FLAT WALL MODULAR INSULATED CONCRETE FORM SYSTEM; all filed on Aug. 20, 2001. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The present invention relates to modular insulating concrete forms of the type which receive poured concrete and are left in place after pouring, thereby becoming an integral part of a static structure being built. The invention is particularly applicable to residential and light commercial construction. The novel forms are usable by homeowners, contractors, municipal, industrial, and institutional personnel in building and improving existing structures wherever insulated load bearing walls are to be built from poured concrete.  
           [0004]    2. Description of the Prior Art  
           [0005]    Left-in-place insulting concrete forms for building foundations and load bearing walls from poured concrete are known. In commercial practice, courses of forms are stacked until the final desired height of a wall is attained. Concrete is poured into the erected forms and allowed to cure. The resultant wall must provide both strength and also insulative protection against the elements. A variety of different insulating concrete forms have been proposed to answer these needs. In order to maximize both strength and insulation values within a given volume dedicated to a left-in-place form wall, the concrete elements must be carefully designed to utilize a minimum amount of concrete, so that the balance of the available volume may be filled with the insulating form.  
           [0006]    There are three distinct types of insulated concrete form systems in the prior art which produce three distinct types of walls.  
           [0007]    Flat wall systems, as their name implies, consist of a flat sheet of foam on both sides, which produce a flat concrete wall therebetween. Assuming 1½″ thick foam on each side, an 11″ thick form would produce an 8″ thick concrete wall.  
           [0008]    Waffle grid systems have a series of rounded posts and beams formed in the foam such that when a poured concrete posts and beams are formed with a web of thinner concrete therebetween. Since the strength of a waffle grid wall is based on the square that can be described within the rounded columns, the same 11″ thick form with 8″ round columns only has the strength of a 6″ straight wall.  
           [0009]    In screen grid systems the forms are generally formed of foam with the two sides of the form joined by foam which, after the concrete pour leaves holes in the concrete which are filled with foam. An 11″ screen grid wall with an 8″ concrete pour doe not have the strength of an 11″ flat wall because the concrete wall is broken at the foam connectors, thereby reducing the fire rating of the wall and its effectiveness as a sound barrier.  
           [0010]    The present invention presents a cross between the flat wall system and the waffle grid system in which a flat wall with square posts and beams, providing greater strength than the rounded waffle grid system.  
           [0011]    Each of the above referenced form systems must, ideally, address several needs.  
           [0012]    First is the necessity for each form be properly aligned with respect to adjacent forms, both vertically and horizontally, to assure that finished wall surfaces are flat and flush. Also, opposing exterior panels of each form section must be held in place without distortion of overall configuration of the finished wall.  
           [0013]    Secondly, it is desirable for the tie brackets within the forms to be aligned vertically, preferably form a continuous vertical structure (a stud), at regular intervals which conforms to standard dimensions of building products (typically, multiples of one foot). It is especially desirable that this uniform placement of tie brackets be consistent in both inside and outside measurements in corner forms. If a form section has tie brackets and associated plates or flanges serving as a structural members which can receive driven and threaded fasteners, and these plates or flanges are located at each end of the form section, then abutment of two form sections results in abutting plates or flanges. This arrangement will likely interfere with even spacing apart of tie brackets at even distance intervals of a whole number of feet since the two abutting end brackets will be spaced on either side of the center line. Thus, if a fastener is driven at the point of abutment, there will be no solid structural member to receive the fastener.  
           [0014]    Flat wall systems are taught by Severino (U.S. Pat. No. 6,308,484), Moore, Jr. (U.S. Pat. No. 6,170,220), Cymbala, et (U.S. Pat. No. 5,896,714), Boeshart (U.S. Pat. No. 5,658,483), Mensen (U.S. Pat. No. 5,657,600), and Young (U.S. Pat. No. 4 730,422), while waffle grid systems are taught by Vaughan, et al. (U.S. Pat. No. 5,845,449), Vaughan, et al. (U.S. Pat. No. 5,709,060), Mensen (U.S. Pat. No. 5,657,600), and Sparkman (U.S. Pat. No. 5,459,971). None of the above references cite a combinations of the flat wall and waffle grid system, as does the present invention, the unique tie bracket of the present invention, which further serves as “studs” spaced at regular intervals, or the combination of spacing and joint reinforcing elements of the present invention.  
         SUMMARY OF THE INVENTION  
         [0015]    The present invention provides insulating concrete forms which provide the best features of both the “flat wall” and the “waffle grid” type forms which satisfy two practical needs. One need is that of forms which can be erected in interlocked stacks which oppose sliding and disengagement of one form with respect to both its vertical and horizontal neighbors. Another need is to provide forms which favor current U.S. building practices with regard to dimensions. It is frequently the case that buildings are designed in increments of one foot and even in increments of four feet. The novel forms satisfy both needs.  
           [0016]    Interlocking is achieved by forming male interlocking members in the top surface of each form, and corresponding female interlocking members in the bottom surface of each form. The male and female interlocks are a combination of tongue and groove edges on respective upper and lower surfaces of each form, and vertically aligned projections and notches extending laterally from the respective tongue and groove so that a stack of forms will enable each form to interlock with a form placed directly thereon and also with the form located directly below, thereby preventing horizontal shifting between vertically stacked forms and ensuring alignment of the tie brackets.  
           [0017]    The forms are configured such that pouring concrete into the void formed between the opposing panels of insulating material generates a modified flat wall configuration having a substantially flat surface with vertical posts and horizontal beams at regular intervals.  
           [0018]    Preferably, the posts and beams are configured as parallelepipeds so that all constituent material thereof contributes to compressive strength in at least one direction of an orthogonal or Cartesian system. No concrete is thus ineffectually used. Overall building costs and weight are minimized, while still affording maximal strength. Also, volume within the form devoted to insulating material is maximized, thereby maximizing temperature insulating value of the form.  
           [0019]    Forms may be either straight or angled, the latter being known either as corner forms or as Tee forms, because angled forms are usually used to form the corner of intersecting walls. Straight forms, corner forms and Tee forms are all dimensioned with regard to modular building. That is, the length of a straight form is preferably four feet, and a Tee form has a length of either two feet or four feet. A corner form has a combined length of both legs of four feet. These dimensions favor building designs laid out in increments of one, two, and four feet. This characteristic minimizes the number of forms which must be cut in length to achieve a desired wall length, thereby saving labor and tending to promote straightness and integrity of the finished poured wall, although forms can be cut to allow for walls of other than even foot lengths.  
           [0020]    Similarly, tie brackets connecting inner and outer walls of each form section are located at one foot intervals along the length of the form, the first being one half foot from the end of the form. This location prevents tie brackets of adjacent abutting forms in one course from interfering with regular spacing of the tie brackets along the entire length of the wall. Rather, tie bracket spacing remains constant. As a consequence, location of concealed flanges or plates of each tie bracket, which is employed to receive and support driven fasteners for fixing plywood and dry wall sections to the wall, is predictable. Effort and expense of mounting either interior or exterior finishing materials on the finished concrete wall is minimized.  
           [0021]    Interlocking members of the form are spaced apart and dimensioned so that clogging with concrete is not a problem when the top of the forms are exposed during concrete placement. If the notches, or female interlocking members, were too small, it would be difficult to dislodge concrete overflow and other materials therefrom. They are spaced apart so that an inordinate number of notches, which would otherwise require cleaning, is avoided.  
           [0022]    Accordingly, it is one object of the invention to provide insulating concrete forms which readily interlock when vertically stacked.  
           [0023]    It is another object of the invention that the novel forms facilitate construction of building designs laid out in increments of one, two, and four feet, as measured from the outside corner of the form system.  
           [0024]    It is a further object of the invention to minimize labor required to erect the forms.  
           [0025]    Still another object of the invention is to enable ready location of concealed tie bracket flanges or plates when driving fasteners into the wall built by the novel forms.  
           [0026]    An additional object of the invention is to maximize strength of the wall for the amount of concrete consumed.  
           [0027]    It is again an object of the invention to maximize insulation value of the wall.  
           [0028]    It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.  
           [0029]    These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0030]    Various other objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein:  
         [0031]    [0031]FIG. 1 is a perspective view of the tie bracket of the present invention.  
         [0032]    [0032]FIG. 2 is a cross sectional detail view of the tie bracket of the present invention at line  2 - 2  of FIG. 1.  
         [0033]    [0033]FIG. 3 is a perspective view of the rebar attachment piece of the present invention.  
         [0034]    [0034]FIG. 4 is a side elevational view of the rebar attachment piece of the present invention in place on the rebar receptacle of the tie bracket of FIG. 1.  
         [0035]    [0035]FIG. 5 is a top perspective view of the straight form of the present invention incorporating the tie brackets of FIG. 1.  
         [0036]    [0036]FIG. 6 is a bottom perspective view of the straight form of FIG. 5.  
         [0037]    [0037]FIG. 7 is a plan view of the straight form showing spacing of various elements.  
         [0038]    [0038]FIG. 8 is a diagramatic view of several of the straight forms stacked as a wall segment.  
         [0039]    [0039]FIG. 9 is a top perspective view of the corner form of the present invention incorporating the tie bracket of FIG. 1.  
         [0040]    [0040]FIG. 10 is a bottom perspective view of the corner form of FIG. 9.  
         [0041]    [0041]FIG. 11 is a partial, perspective view of the corner bracket of the corner form.  
         [0042]    [0042]FIG. 12 is a plan view of a corner form of the present invention showing spacing of various elements.  
         [0043]    [0043]FIG. 13 is a diagramatic view of two of the corner forms and a straight form stacked as a wall segment.  
         [0044]    [0044]FIG. 14 is a plan view of a first embodiment of the Tee form of the present invention.  
         [0045]    [0045]FIG. 15 is a plan view of a second embodiment of the Tee form of the present invention.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0046]    [0046]FIG. 1 of the drawings shows a wall tie bracket  10  according to the present invention. Tie bracket  10  comprises a first elongate plate  12 , a second elongate plate  14  spaced apart from plate  12 , and a web  16  securing plates  12 ,  14  in spaced apart relation. Web  16  includes a plurality of vertically spaced apart spanning members  18 ,  20 ,  22 ,  24  which extend horizontally, in the depiction of FIG. 1, from plate  12  to plate  14 , to join plates  12  and  14  structurally. Spanning members  18 ,  20 ,  22 ,  24  are connected to one another by braces  26 ,  28 . Spanning members  18 ,  20 ,  22 ,  24  and braces  26 ,  28  are preferably formed by intersecting ridges selectively orthogonally oriented to one another, as shown in FIG. 2. That is to say, that each of the spanning members  18 ,  20 ,  22 ,  24  and braces  26 ,  28  are formed of a plurality of orthogonal ridges extending along substantially the full length of the spanning member or brace, such that each spanning member or brace has cross-sectional shape of a “T”(as shown at FIG. 2) or a “+”. First elongate plate  12  and second elongate plate  14  can also each be seen in FIG. 1 to have an orthogonal ridge extending substantially along the full length of each. This cross sectional configuration maximizes strength of the respective member while minimizing the amount of constituent material thereof. Circumferentially closed openings  30 ,  32 ,  34 ,  35 ,  36  are thus formed in web  16 .  
         [0047]    At least two horizontal rows of circumferentially closed openings are formed when plates  12 ,  14  are oriented vertically, as shown in FIG. 1, there being at least two adjacent openings in each horizontal row. The arrangement of openings between horizontal and vertical members results in a very useful array of openings. First, it will be seen that outer openings  30 ,  36  and inner or central openings  32 ,  34 ,  35  all formed between spanning members  20 ,  22 , are oriented such that their lengths extend horizontally. Additionally, it can be seen in FIG. 1 that the orthogonal ridge which extends down one side of each plate  12 ,  14  has a break therein which coincides with the outer openings  30 ,  36 . As a consequence, with the center lines of outer openings  30 ,  36  and central openings  32 ,  34 ,  35  arranged in line, and the break in the orthogonal ridge of plates  12 ,  14 , it is easy for a mechanic to saw through tie bracket  10  horizontally without diminishing structural integrity of either remaining section of the tie bracket and of the entire form module. This must occasionally be done to create a form half the height of the uncut form to limit form height to the desired height of a finished wall. Furthermore, location of end openings  30 ,  36  where they terminate respectively at plates  12 ,  14  creates convenient electrical cable and conduit chases. To protect cables, openings  30 ,  36  are bounded by horizontally oriented ridges. It will be seen that outer openings  30 ,  36  each has a height greater than that of central openings  32 ,  34 ,  35 . The extra height of openings  30 ,  36  accommodates plural cables and conduits, whereas central openings  32 ,  34 ,  35  require only nominal height for accommodating a saw blade. Openings  45 ,  47  are each dimensioned and configured to receive an electrical work box (not shown) which may be installed by sawing away an appropriate portion of plate  12  or  14 .  
         [0048]    Uppermost spanning member  18  has an upwardly open receptacle  38  for receiving reinforcing bars (rebar)(not shown). The height of receptacle  38  is greater than the width, so that two sections of rebar can be laid in receptacle  38  and supported in overlying, overlapping relationship to facilitate splicing. Uppermost spanning member  18  also has a small circumferentially closed openings  40 ,  42 ,  43  located above spanning member  18 . Openings  40 ,  42 ,  43  accommodate tie wires and tethers for scaffolding (not shown), bracing (not shown), and general purpose securement to tie bracket  10  and larger elements such as plumbing and HVAC conduits. Lowermost spanning member  24  similarly has two openings  44 ,  46  formed therein.  
         [0049]    It is often desirable that the rebar within a poured concrete wall be offset from the center of the wall toward one surface of the wall. For this purpose, a rebar attachment piece  50 , shown at FIG. 3 and  4  may be used. Formed of the same material as the tie bracket  10  consists of at least one, preferably two, “U” shaped receptacle  52 , with an attachment receptacle  54  adapted to fit over one arm of receptacle  38 , as at FIG. 4. It would, however, be evident to one skilled in the art that rebar attachment piece  50  could have any number of “U” shaped receptacles  52 , each variation in number being adaptable to different applications. The base  56  of the rebar attachment piece  50  is formed to snugly fit the contour of the exterior of receptacle  38 . It would be evident to one skilled in the art that other methods of attaching the rebar attachment piece to the tie bracket  10  without departing from the spirit of the present invention.  
         [0050]    Use of a rebar attachment piece  50  allows for economy in production of form in that the tie bar  10  need only have provision for a central rebar, with provision being made for offset only in the locations when and where it is needed.  
         [0051]    It would be evident to one of ordinary skill in the art that while the rebar attachment piece  50  is designed for use with the insulated concrete form system of the present invention, it could easily be adapted for similar systems currently known in the art or to be developed.  
         [0052]    Referring now to FIG. 5 through  7 , the principal function of tie bracket  10  is to connect opposing insulating panels  110 ,  112  of insulating concrete forms  100  for the purpose of holding panels  110 ,  112 . Panel  110  is an insulating panel preferably formed from expanded foam. Panel  112  is a second insulating panel formed from expanded foam, and is located on the opposed side of the final form  100 , which comprises panels  110  and  112  and a plurality of tie brackets  10 . Tie brackets  10  span and connect panels  110  and  112 . Panels  110  and  112  are dimensioned and configured such that the height of each plate  12  or  14  (see FIG. 1) of the various tie brackets  10  are equal to the height of each panel  110  or  112 . This characteristic improves vertical load bearing strength of the form, and further, forms a “stud” which may be used to attach structural elements, such as paneling or sheetrock, to a finished wall.  
         [0053]    Form  100  is dimensioned and configured so that as adjacent forms are located beside one another, they interlock with one another and as succeeding courses of forms  100  are formed by stacking forms  100  on one another, they interlock with one another. This characteristic is enabled by a tongue  114  at one vertically extending edge of each of panel  110 ,  112  and a mating groove  116  at the other vertically extending edge, as well as a top tongue  118  with cooperating projections  120 ,  122 ,  124  and bottom groove  132  with cooperating notches  126 ,  128 ,  130 . As previously state, the upper surface of panel  110  has a plurality of inward projections  120 ,  122 ,  124  formed therein, extending laterally inwardly of form  100  from tongue  118 . Panel  112  is essentially a mirror image of panel  110 , so that description set forth regarding panel  110  will be understood to apply equally to panel  112 . The lower surface of panel  110  bears a bottom groove  132  with notches  126 ,  128 ,  130  corresponding to projections  120 ,  122 ,  124 , extending inwardly of form  100  from groove  132 . Each notch  126 ,  128 ,  130  is dimensioned and configured to receive one projection  120 ,  122  or  124  of another form  100  in close cooperation therewith such that a form  100  placed above can interlock with a form  100  located below when pressed into mutual engagement. To this end, notches  126 ,  128 ,  130  are located directly below respective projections  120 ,  122 ,  124 , thereby ensuring proper offset in increments of one foot of forms  100  when stacked. Additionally, at each end of the upper surface of panel  110  is a half projection  134 ,  136 , such than when two forms  100  are placed end to end, the two half projections  134 ,  136  form the equivalent of a full projection. Likewise, a half notch  138 ,  140  is located at each end of the lower surface of panel  110 , such that when two forms  100  are place end to end, the two half notches  134 ,  136  form the equivalent of a full notch. Thus, when two forms  100  are stacked, the two half projections  134 ,  136  will mate with one of the full notches  126 ,  128 ,  130  and the two half notches  138 ,  140  will receive one of the full projections  120 ,  122 ,  124 . In a four foot form  100 , the projections  120 ,  122 ,  124  are space apart on one foot centers beginning from the end of the half projections  134 ,  136  adjacent the ends of the straight form  100  (FIG. 7), with the notches  126 ,  128 ,  130 , situated directly below projections  120 ,  122 ,  124  having the same spacing. Based on the spacing of the protrusions and grooves, the straight form  100  need not be limited to the four foot length disclosed, but rather, could be produced in any length which is a multiple of one foot, so long as the form is manageable.  
         [0054]    In addition to the projections  120 ,  122 ,  124  (FIG. 5) on the upper surface of panels  110 , additional projections  142 ,  144  are situated at the mid point between projections  120 ,  124  and the half projection  134 ,  136  adjacent each, respectively. Likewise, additional notches  146 ,  148 ,  150 ,  152  are formed in the lower edge of panel  110  at the midpoint between each of the notches  126 ,  128 ,  130  and half notches  138 ,  140 . The additional projections  142 ,  144  and additional notches  146 ,  148 ,  150 ,  152  (FIG. 6) are of a length different from that of projections  120 ,  122 ,  124  and half projections  134 ,  136  and notches  126 ,  128 ,  130  and half notches  128 ,  140  to assure proper vertical alignment of forms  100 , and thus the vertical alignment of tie brackets  10  and the “stud” of the elongate plates  12 ,  14  within the wall. The intent of additional projections  142 ,  144  and additional notches  146 ,  148 ,  150 ,  152  is to form a more solid connection between a straight form  100  and vertically adjacent corner forms  200  as they are stacked vertically in the wall assembly, as will be explained in greater detail, hereinafter. It is important to note that there are more additional notches than additional projections, as the additional projections are designed to reinforce the joints between forms and may line up with notches along the length of the form  100 , not just at the ends, especially in the joint between straight forms  100  and corner forms  300 .  
         [0055]    It would be evident to one skilled in the art that other additional projections and notches would be equally effective, so long as the recurring, symmetrical pattern of twelve inches, on center, is maintained.  
         [0056]    The present invention is susceptible to variations and modifications which may be introduced thereto without departing from the inventive concept. Illustratively, there is no necessity that the projections and notches be inwardly directed. They could be outwardly, upwardly, or otherwise directed if desired as long as they accommodate interlocking as described herein.  
         [0057]    [0057]FIGS. 9 and 10 of the drawings shows the essential nature of a corner form  200 , which forms a corner in the form system. Corner form  200  includes an interior insulating panel  210  formed from expanded foam, having a first leg  212  and a second leg  214 . Legs  212 ,  214  are each straight and positioned to form an angle with respect to one another. Typically this angle is substantially 90 degrees, though any angle suited to a particular use of the form system would fall within the scope of the invention. An exterior insulating panel  220  formed from expanded foam has a first leg  222  and a second leg  224  which are preferably straight and positioned parallel to legs  212 ,  214  of panel  210 , respectively, with legs  222  and  224  positioned to form a similar angle as that formed by legs  212  and  214 . Panels  210 ,  220  are connected and held in spaced apart, parallel orientation by tie brackets  10  which include members embedded within panels  210 ,  220 . Only cross members of tie brackets  10  spanning panels  210 ,  220  are visible.  
         [0058]    It will be seen that legs  212  and  214  of interior panel  210  are different in length. Similarly, legs  222 ,  224  of panel  220  are different in length. In most cases, to conform to general building practices, oblique angle  216  is a right angle. Legs  214 ,  224  of panels  210 ,  220  terminate in a plane normal to legs  214 ,  224 . The effective length of legs  214 ,  224  is indicated by arrow  230  (FIG. 12). A groove  226  is formed in the length of the free vertical edge of leg  214  and a groove  228  in the length of the free vertical edge of leg  224 . Grooves  226 ,  228  cooperate with the tongues  114  of an adjacent straight form  100  to ensure a tight fit between corner form  200  and an adjacent straight form  100 .  
         [0059]    In similar vein, second legs  212 ,  222  of respective panels  210 ,  220  terminate in a second plane which is normal to first leg  212  of panel  210 . Effective length of legs  212 ,  222  of panels  210 ,  220 , respectively is indicated by arrow  232  (FIG. 12). A tongue  234  is formed in the length of the free vertical edge of leg  212  and a groove  236  in the length of free vertical edge of leg  222 . The tongues  234 ,  236  cooperate with the grooves  116  of a straight form  100  to ensure a tight fit between corner form  200  and an adjacent straight form  100 . The combined effective lengths of legs  222  and  224  is four feet. The length indicated by arrow  232  is preferably thirty inches, while the length indicated by arrow  230  is preferably eighteen inches.  
         [0060]    Panels  210 ,  220  each have a respective upper surface and a lower surface. A tongue  238 ,  240  is formed in the upper surface of each of panels  212 ,  220 , respectively and a cooperating groove  242 ,  244  is formed in the lower surfaces of each of panels  212 ,  220 , respectively. A projection  246  is formed in the upper surface of leg  224 , and two projections  248 ,  250  are formed in the upper surface of leg  222 . A projection  252  is formed in the upper surface of leg  212 . Correspondingly, a notch  254  is formed in the lower surface of leg  224  and notches  256 ,  258  are formed in the lower surface of leg  222 , while a notch  260  is formed in the lower surface of leg  212 . Notch  254  is located directly below projection  246 , notches  256 ,  258  are located directly below corresponding projections  248 ,  250 , and notch  260  is located directly below corresponding projection  252 . A half projection  262 , having one half the length of projections  246 ,  248 ,  250  and  252 , is located on each of the four upper ends of panels  212 ,  214 ,  222  and  224 . Each half projection  262  is configured to occupy one half of a notch, with a half projection  165  of a straight form  100  occupying the other half of the same notch.  
         [0061]    An additional projection  264  is situated on the upper surface of leg  222  at a point equidistant between projection  250  and half projection  262  and projection  252  and half projection  262 , respectively. Additional projections  264  have a length different from both projections  246 ,  248 ,  250 ,  252  and half projections  262 . Additional projections  264  and notches  266 , which are vertically aligned with and sized to cooperate with one another, provide additional strength to the junction between vertically stacked corner forms  200  and adjacent straight forms  100 . This added strength at the corners is important, as greater outward pressures are exerted at the corners than along the straight length of a wall as the wet concrete is poured.  
         [0062]    Plural corner forms  200  can be stacked in the manner shown in FIG. 13 and interlocked by interfitting projections of one corner form  200  into notches of the corner form  200  above.  
         [0063]    Projections  248 ,  250  and notches  256 ,  258  are spaced apart from one another by a distance interval  268  which is twice the magnitude of distance interval  270  existing between additional projections  264  and each of its neighboring projections, the half projections  262  and the projections  252  of panel  200 .  
         [0064]    [0064]FIG. 12 shows spacing of tie brackets  10 . Measuring from the outside corner of exterior panel  200 , center line  282  of a first tie bracket  10 A is located at a distance interval  284  of one foot from the corner  275  at the juncture of leg  222  with leg  224 . Center line  286  of tie bracket  10 B is located at a distance interval  288  of one foot from center line  282 , and at a distance interval  290  of six inches from the free end of leg  222 . In a similar manner, center line  292  of tie bracket  10 C is separated by a distance interval  294  of one foot from the corner  275 , and by a distance interval  296  of six inches from the free end of leg  224 .  
         [0065]    It is important that center lines  282 ,  286 ,  292  pass through the centers of the plates  12 ,  14  of the tie brackets  10 . It will be appreciated that tie brackets  10  have end plates  12 ,  14  which are embedded within insulating panels  212 ,  220  to anchor the tie brackets  10  within insulating panels  212 ,  220 . These plates  12 ,  14  provide broad, flat surfaces typically parallel to the outer surfaces of legs  222 ,  224  of exterior panel  220  to which fasteners (not shown) may be engaged by threading and friction. It is strongly desirable that these plates be located on one foot centers, measuring from corner of the juncture of legs  222 ,  224  for the purpose of enabling craftsmen to affix construction elements such as paneling and gypsum wall board sheets (neither shown) to a wall built utilizing form  200 . This is readily accomplished by placing a construction element against the form and nailing or otherwise fastening the construction element at one foot intervals to the form.  
         [0066]    In summary, it will be seen that the center line of each tie bracket  10 A or  10 C which is adjacent to corner  275  is spaced apart from the corner  275  by a distance interval which is a whole number multiple of one foot. Each tie bracket  10  of any one leg is spaced apart from every adjacent tie bracket  10  by a distance interval which is a whole number multiple of measurements of one foot. The foregoing holds true regardless of the actual number of tie brackets provided and of the overall length of each leg of the corner form. This also holds true along the length of a wall, as in relation to connecting and interlocking with adjacent straight forms. Like the straight form  100 , while disclosed as having a combined length of four fee, the corner form  200  could be formed in any multiple of one foot, so long as the form remains manageable.  
         [0067]    Looking now at the left of FIG. 12, it will be seen that corner  275  is formed at the intersection of legs  222 ,  224 . A vertical bracket  300  (FIG. 11) is optionally embedded within exterior panel  220  in a vertical opening  298  (see FIG. 12) formed around bracket  300  at corner  275 . Referring also to FIG. 11, bracket  300  includes a first plate  302  disposed parallel to leg  222  and a second plate  304  disposed parallel to leg  224  of panel  220 . Plates  302 ,  304  both reinforce the corner of form  200  and also provide fastener receiving surfaces similar in function to the plates  12 ,  14  of tie brackets  10  (see FIG. 13). Bracket  300  preferably includes webs bracing  306 ,  308  and reinforcing plates  310 ,  312  to stiffen and strengthen bracket  300 .  
         [0068]    Corner form  200  also includes bulkhead retainers  314 ,  316  (FIGS. 9 and 10) formed on the ends of each leg of panels  210 ,  220 . Retainers  314 ,  316  may comprise any structure which would surround or otherwise entrap a flat panel placed just within the ends of the form to close the otherwise open ends. The precise nature of retainers  314 .  316  is not critical to their function.  
         [0069]    Corner form  200  is intended to be formed in both right hand (R) and left hand (L) versions, to accomplish staggered joints, as at FIG. 13, each being a mirror image of the other, with the exception that tongue  234  and groove  246  would be reversed in position.  
         [0070]    While the corner form  200  provides for two walls to meet in an “L”, concrete walls are often poured in a “T” configuration, as well, with a wall extending outwardly from the middle of a continuing wall. Straight forms  100  could be adapted, on site to create a “T”, but the Tee form  300  provides a ready made form for this purpose.  
         [0071]    Referring now to FIG. 14 through  17 , the Tee forms  400  and  400 A are formed substantially like the straight form  100 , with a first panel  410  having a tongue  414  at one end and a groove  416  at the other. An upper tongue  432  extends along the length of the upper surface of panel  410  and a lower groove along the lower surface, which is not visible, but is the same as the groove shown in lower edges of the other embodiments of wall forms. Projections  420  are situated at regular intervals of one foot on center, as in the straight form  100 , with a half projections  434  at each end. The opposing panel  412  is a mirror image of panel  410  with the exception that a void is formed between the center most two of tie brackets  10  which join the panels  410  and  412 . Tie brackets  10  are situated at regular intervals of one foot on center, commencing one half foot from the end of panel  410 . As in the straight form, additional projections  146  are formed  6 ′ from the end of each panel, at the first tie bracket  10 , additional projections  146  being of a different length than both projections  420  and half projections  434 . Panels  410 ,  412  form what would be the top cross member of the letter “T”, and would typically be formed in  24 ″ (Tee form  400 A)(FIG  15 ) and  48 ″ (Tee form  400 )(FIG. 14) length versions. Corresponding notches  426  and half notches  440  are formed in the lower surface of panels  410 ,  412 .  
         [0072]    Extending outwardly from the void in panel  412  is what would be the vertical leg of the letter “T”, again consisting of a portion of a typical straight form  100 . As in the cross segment, tie brackets  10  are spaced on one foot centers, commencing one half foot from the end, a half projection  434  is situated at the end of each panel. In Tee form  400  the vertical leg is typically 6 3/4 ″ long (18″ from the outer surface of panel  410 ), and therefore there is no projection along this leg. In Tee form  400 A, however, the vertical leg is typically 18 3/4 ″ long (30″ from the outer surface of panel  410 ) and a projection  420  is used. Corresponding notches and half notches are formed in the lower surfaces, which are the same as the notches and half notches shown in the other embodiments of the form. In both the Tee form  400  and  400 A, a tie bracket  10  is situated such that the “stud” formed by the elongate plates  12 ,  14  abut in both panels joining to form the wall corners.  
         [0073]    As previously stated, the Tee form is formed in a 48″×18″ (Tee form  400 ) and 24″×30″ (Tee form  400 A), thereby allowing staggering of the joints between the Tee forms  400 ,  400 A and adjacent straight forms  100 . As with the straight form  100 , however, the Tee form  400 / 400 A could be of any length in a multiple of one foot, so long as the size of the form remains manageable.  
         [0074]    It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims: