Concrete forming system

An concrete form system includes opposed polystryrene panels stacked to form a pair of parallel, spaced-apart walls, at least one of the walls having panels which are smooth on their inward surface. Tie slots are formed in the upper and lower edges of the panels and are spaced evenly such that slots in vertically abutting panels are aligned. The panels are horiziontally staggered to strengthen vertical joints. A single tie is utilized to interlock two vertically abutting panels in each wall. A special tie design is used with the smooth-faced panels to allow the panels to be removed after a concrete wall has been formed. Another embodiment of the tie design utilizes an enlarged outer paddle with a projecting rib which allows connection of vertical walers directly to the tie.

TECHNICAL FIELD 
The present invention relates generally to a new and improved concrete 
forming system, and more particularly to a concrete forming system which 
utilizes polystyrene panels which may be constructed utilizing wall ties 
to hold the panels in parallel relation, and which may be left as 
permanent insulation on the formed wall or removed to form an exposed 
concrete wall. 
BACKGROUND OF THE INVENTION 
While wall-forming systems have been in use for many years, a recent 
development in this industry is in the use of polystyrene panels as forms 
for poured concrete walls. After the concrete has hardened, the panels 
remain in place on the walls to serve as permanent insulation. One example 
of this recent development may be found in U.S. Pat. No. 4,706,429 
entitled "Permanent Nonremovable Insulating Type Concrete Wall Forming 
Structure." 
This new wall-forming system utilizes a system of "blocks," each block 
comprising a pair of polystyrene panels connected in parallel, 
spaced-apart alignment by a series of rigid synthetic plastic ties between 
the panels. Each panel has a series of T-shaped slots along its upper and 
lower edges, into which T-shaped ends on the plastic ties are inserted to 
"lock" the panels in spaced-apart relation. The upper and lower edges of 
the panels have castellations which further serve to lock the panels in 
vertical and horizontal relationship. The end edges of each panel have 
dovetail type tongue and groove joints to allow for slidable 
interconnection. The interior face of each of the panels is striated so as 
to allow modular end panels to be slidably located between the wall panels 
at any given location, and to promote adhesion between the panels and 
concrete. 
Once concrete is poured between the panels, the concrete will adhere to the 
striations on the panels and hold the panel in place. Since the T-shaped 
ends of the ties do not extend completely through the panels, a smooth 
panel surface on the exterior of the wall could be finished as desired. It 
can be seen that the panels of the prior art provide a form for pouring 
the concrete, as well as insulating the wall once the concrete has 
hardened. 
While this nonremovable insulated concrete form system has advantages over 
the prior art, the system is limited by the fact that the panels are 
permanently adhered to the concrete wall. Thus, such a system is not 
capable of use on those occasions where an exposed concrete surface is 
desired. On those occasions, it was necessary to revert to the older 
methods of wood form boards, steel bracing within the concrete, and 
extensive exterior bracing to hold the form boards in the appropriate 
alignment. Such a system is cumbersome, utilizes heavy material, and is 
difficult to utilize to produce accurately aligned walls. Furthermore, the 
materials of old methods of forming concrete walls must be moved from site 
to site, thereby requiring storage facilities. 
A further problem with the prior art form systems is in the fact that each 
of the panels requires significant machining in order to create the tongue 
and groove portions, the striations, and the castellations in order to 
lock the panels together. This can significantly increase the cost of the 
panels because of time and material spent. Furthermore, use of 
castellations on the panels forms small portions which are easily broken 
off the panels during construction. This leaves unsightly holes and 
pockmarks in the face of the finished wall. 
Another problem with prior art form systems is in the large number of ties 
which must be utilized in order to hold the panels in spaced-apart 
relationship. For instance, the system disclosed in U.S. Pat. No. 
4,706,429 requires a series of ties spaced intermittently along both the 
top and bottom edges of every panel. Since the ties are not evenly spaced 
vertically and horizontally, conventionally dimensioned coverings are not 
conveniently attached to the ties through the panel surface. 
A further problem with prior art concrete forming systems is in the fact 
that the height dimension of the panels limits the width of the wall which 
may be poured. Typically, conventional panels have a height of 
approximately 12 inches, and are useful in forming walls of less than 12 
to 14 inches. Attempts to pour walls thicker than 14 inches result in 
bulging of the panels between the vertically spaced horizontal edges. 
Finally, as mentioned above, prior art forming systems utilized panels 
which were permanently mounted to the wall. This was partly due to the 
system of incorporating the ties into each panel, and partially due to the 
specific configuration of the panels themselves. In any case, the option 
to be able to remove the panels from the wall is a much desired advantage, 
and was heretofore unknown. 
It is therefore a general object of the present invention to provide an 
improved concrete wall forming system. 
Another object of the present invention is to provide a wall form system 
including pairs of oppositely disposed polystyrene panels, at least one of 
the panels being removable from the wall once the wall has been formed. 
Still another object of the present invention is to provide an improved tie 
for use in the concrete wall forming system of this invention. 
Still another object is to provide polystyrene panels for an improved 
concrete forming system which do not require complex machining. 
Yet another object of the present invention is to provide a wall form 
system capable of forming exceptionally thick walls. 
A further object is to provide an improved wall form system in which panels 
may be removed and used again. 
Still a further object of the present invention is to provide an improved 
wall tie for a wall forming system which will allow direct connection of 
walers. 
Another object of the present invention is to provide an improved method 
for forming a poured concrete wall. 
Yet another object is to provide a method for forming a concrete wall with 
at least one surface of the wall exposed. 
These and other objects will be apparent to those skilled in the art. 
SUMMARY OF THE INVENTION 
The improved concrete forming system of this invention includes a series of 
opposed polystyrene panels stacked on top of one another to form a pair of 
parallel, spaced-apart walls, the panels forming at least one of the walls 
being smooth on their inward surface so as to prevent adhesion with 
concrete poured between the walls. Tie slots are formed in the upper and 
lower edges of the panels and are spaced evenly and identically on every 
panel so that the panels may be interchanged. A single tie is utilized to 
interlock two vertically abutting panels in each wall, each tie end being 
engaged between vertically abutting pair slots in the abutting edges of 
the panels. A conventional end panel formed of dimensional lumber or the 
like is utilized to retain concrete between the walls formed of panels and 
the opposite end panels. 
A special tie is utilized in connection with panels that will be removed 
after a concrete wall has been formed. The ends of the tie have a pair of 
spaced-apart paddle members which retain the thickness of the panel 
therebetween. A pair of small-cross-section legs hold the paddles in 
spaced-apart relation, and a pair of diverging small-cross-section legs 
connect the paddle members to the elongated strap of the tie. Once the 
concrete wall has been formed, the outer paddle is removed by applying a 
sharp vertical blow thereto, thereby breaking the small-cross-section legs 
of the tie. Once the outer paddle is removed, the panel may be removed and 
a sharp vertical blow applied to the inner paddle to break the 
small-cross-sectional diverging legs of the tie. Thus, an exposed concrete 
surface may be produced using the special tie and method of this 
invention. 
Another embodiment of the invention is designed to specifically allow use 
of portions of prior art systems. If it is desired to produce a concrete 
wall with one insulated surface and one exposed surface, the permanent 
non-removable wall-forming panels of the prior art may be utilized to form 
one wall of the oppositely disposed parallel walls of the form of this 
invention. Tie slots must then be cut in the present applicant's panels at 
spacings matching those of the prior art panels. The applicant's new tie 
design may be utilized in the T-shaped slots of the prior art 
non-removable panels, and may also be utilized in the applicant's 
removable-type panels. In order to allow use of prior art panels, it is 
necessary to form the panels with interlocking members on the top, bottom 
and side edges, since the ties do not interlock the panels. 
Another embodiment of the tie design utilizes an enlarged outer paddle 
disposed outwardly of the outward face of the panels. A structural rib on 
the paddle provides strength to the paddle for use in panels having 
greater height dimensions. The rib also is utilized to connect vertical 
walers directly to the rib. Once the concrete wall has been formed it is 
possible to remove the enlarged outer paddle and the panels in the same 
manner as with the previously described tie member.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings, in which similar or corresponding parts are 
given the same reference numeral, and particularly to FIG. 1, wherein a 
concrete form system of the prior art is designated generally at 10, and 
includes a pair of opposed panels 12 of polystyrene connected in spaced 
relation by synthetic plastic ties 14 engaged in T-shaped slots 15. Panels 
12 of the prior art form system are solid two inch panels of polystyrene 
which are approximately twelve inches high and twenty or forty inches 
long. Each panel 12 has male castellations 16 along its top edge and 
matching female castellations 18 along its under edge. A "block" 20 is 
composed of a pair of panels 12 fastened together with ties 14 inserted 
along both the top and bottom edges. The blocks 20 are placed one on top 
of the other and pressed together, the male and female castellations 16 
and 18 interlocking the blocks 20 vertically The vertical ends of each 
panel 12 have a tongue 22 or groove 24 and may be interlocked as required. 
Rib and groove striations 26 are cut into the inner face of each panel 12 
and allow "closure panels" (not shown) to be inserted between the two 
panels 12 to form a four-sided form to retain concrete. Once concrete is 
poured between panels 12 to form a wall, the panels 12 will be permanently 
affixed to the wall to provide insulation. 
The applicant has found many applications wherein at least one side of a 
poured concrete wall is desired to be exposed and not insulated as in the 
prior art. In such a case, it is clear that the prior art concrete form 
system is unworkable since the panels 12 are permanently affixed to the 
wall. For this reason, the applicant has devised a concrete form system 
which allows one or both sides of the concrete wall to be exposed. In 
order to provide an exposed wall surface, it is necessary to provide form 
panels which are removable once the wall has been poured and hardens. In 
order to provide for the removability of the panel, the applicant herein 
has provided a new tie which is presently the subject of co-pending patent 
application, Ser. No. 101,055, filed Sept. 25, 1987 entitled "Adjustable 
Tie", now U.S. Pat. No. 4,765,109. The disclosure of the co-pending 
application is incorporated herein by reference. 
Referring now to FIG. 2, one embodiment of the applicant's invention is 
shown generally at 30, combining panels 12 of the prior art with 
applicant's new panel 32 and new tie 34. In this case, a series of prior 
art panels 12 form one vertical wall 31 of form system 30, while a series 
of vertically and horizontally stacked panels 32 form the opposing, 
parallel wall 33 of form system 30. As will be described in more detail 
below, panels 32 of wall 33 may be removed from the concrete wall formed 
in form system 30, while panels 12 will remain permanently in place. 
Each panel 32 has an upper edge 36, lower edge 38, and a pair of side edges 
40 (one side edge is not shown). Each upper edge 36 and one side edge (not 
shown) as a tongue 44 (similar to tongue 22 on panel 12) centered 
therealong corresponding to a groove 46 centered in the lower edge 38 and 
other side edge 40 of an adjacent panel 32. It can be seen that this 
tongue and groove joint will interlock adjoining panels 32 both vertically 
and horizontally. 
A series of slots 48 are cut downwardly in the upper edge 36 of each panel 
32, and are modularly spaced therealong to be directly opposite slots 15 
in panels 12. A second series of slots (not shown) are cut upwardly in the 
lower edge 38 of each panel 32, the lower slots being vertically aligned 
with upper slots 48. The slots are cut to a depth sufficient to receive 
the entire height of a tie 34, as seen in the drawings. In the embodiment 
shown in FIG. 2, each panel 32 is two inches thick, twelve inches in 
height and may be twenty or forty inches in length, so as to correspond 
with panels 12 of the prior art. 
Referring now to FIGS. 6 and 7, wall ties 34 and 34,, for use with 
applicant's form systems, are shown in more detail. The one-piece wall tie 
34 shown in FIG. 6 includes an elongated strap 52 having a generally 
rectangular cross-section. At each end 52a and 52b a pair of diverging leg 
members 54 project outwardly and are affixed to an inner paddle member 56. 
Paddle 56 is a thin rectangular plate-like member oriented with its flat 
faces 56a and 56b perpendicular to the longitudinal axis of strap 52. As 
shown in FIG. 6, legs 54 are of small cross-section and form a generally 
equilateral triangular configuration in connection with paddle member 56. 
A set of three parallel and spaced-apart legs 58 project outwardly from 
the outer face 56b of each paddle 56, the legs being vertically aligned 
within the same plane as legs 54 and strap 52. Legs 58 extend from paddle 
56 to an outer paddle 60, which is oriented parallel to inner paddle 56. 
Legs 58 and legs 54 are of substantially the same thickness and 
cross-section. The distance between paddle 56 and 60 is generally two 
inches, but may be adjusted for the particular thickness of panel upon 
which the tie 34 will be utilized. 
Referring now to FIG. 7, a two piece tie 34' is shown which has the same 
general characteristics as tie 34. Two piece tie 34' utilizes a pair of 
corresponding and selectively connectable elongated straps 62 and 64, each 
strap having alternately spaced pegs 66 and apertures 68 which may be 
fastened to the corresponding apertures and pegs on the opposite strap 64. 
The straps may be connected in a variety of lengths such that the distance 
between the inner paddles 56' may be varied. This in turn allows for the 
width of the concrete wall to be any thickness desired. Two piece tie 34' 
also allows a wall to be poured around an existing pipe or conduit, since 
the opposing walls 31 and 33 may be connected together after being placed 
on opposite sides of the pipe, the tie halves 34a and 34b being connected 
by connecting straps 62 and 64 at the desired length. 
While ties 34 and 34' are shown with a set of three legs 58 and 58' between 
inner and outer paddles 56 and 60, and 56' and 60', only the upper and 
lower legs are necessary for minimal functioning of the invention. The 
center leg is preferred, however, in order to strengthen the connection 
between the paddles, and prevent any twisting to occur between the inner 
and outer paddles. It is critical to note, however, that a solid web 
between inner and outer paddles 56 and 60 is unworkable. Similarly, legs 
54 must diverge from strap 52 so that they are separated where they fasten 
to paddle 56. This is because paddles 60 and 56 will be removed by 
breaking them off from the remainder of the tie 34 or 34' after the 
concrete wall has been poured. Use of a solid web makes it impossible to 
easily remove the paddles 56 and 60 as discussed hereinbelow. 
Another embodiment of a tie is shown in FIG. 13 and designated generally as 
34". Tie 34" includes tie halves 34a" and 34b", which are identical to tie 
halves 34a and 34b of FIG. 7, except for the peg 66" and aperture 68" 
arrangement on strap portions 52". Tie halves 34a" and 34b" are connected 
together with a center elongated strap 34c, and may be adjusted to a 
variety of lengths. It should be noted that both halves 34a" and 34b" are 
attached to the same side of center strap 34c, such that legs 58" on each 
half 34a" and 34b" are aligned. 
Referring now to FIGS. 8 through 10, the sequence of drawings shows how the 
panels may be removed from a hardened concrete wall 70 so as to leave the 
wall 70 exposed. While panels 82 in FIG. 8 have the configuration of those 
shown in the embodiment of FIG. 3, the method for removing panels 82 is 
the same as with panels 32. FIG. 8 shows how a hammer 72 is used to apply 
a sharp vertical blow to the outer paddle 60 which is exposed on the 
outside surface of each panel 82. Because of the small cross-section of 
legs 58, and the use of a plastic material, legs 58 will readily break, 
allowing paddles 60 to fall to the ground. Once outer paddles 60 are 
removed from one entire panel 82, panel 82 may be pulled outwardly away 
from the wall 70 and removed. 
FIG. 9 shows concrete wall 70 with a number of panels 82 removed, leaving 
inner paddles 56 and portions of broken legs 58 projecting outwardly 
therefrom. Because panels 82 have a smooth inner surface, they do not 
adhere to concrete wall 70 and are easily removed. FIG. 10 shows how a 
conventional scraper 74 may be used quickly and efficiently to knock off 
the remaining portion of the exposed tie--namely, legs 58 and inner paddle 
56. Scraper 74 is utilized to apply a sharp blow to legs 58 which breaks 
the tie at the ends of diverging legs 54 (see FIG. 6) such that legs 58 
and inner paddle 56 fall to the ground. Once removed, small indentations 
76 are left in the wall surface with only a cross-section of legs 54 seen. 
Each indentation 76 may be quickly and easily filled with concrete so as 
to leave a smooth wall surface, if so desired. 
It can therefore be seen that it is critical that legs 54 and legs 58 be of 
small cross-section and of a "breakable" material, such as plastic, such 
that a sharp blow will cause a fracture to occur in legs 54 or 58 so as to 
remove the paddles 56 and 60. It is further necessary that panels 82 have 
a smooth interior face so as to allow ease of removal of the panel from 
the concrete wall 70. Use of a striated face 26 as shown in FIG. 1 of the 
prior art, would prevent removal of the panel 12. 
Referring now to FIG. 3, a second embodiment of the concrete forming system 
is designated generally at 80, and includes a pair of parallel vertical 
walls 81 and 83, composed of oppositely disposed polystyrene panels 82 
having smooth inner and outer faces. The applicant has discovered that 
reducing the height of panels 82 to approximately eight inches provides 
heretofore unrealized advantages over the prior art. The panels 82 are 
still preferably two inches in thickness and may be of any standard 
length, but slots 84 along the upper edge 86, and slots (shown in FIG. 4 
as 84' and 88') in the lower edge 80 of each panel 82 are spaced 
horizontally at eight inch intervals, such that ties 34' are evenly spaced 
in both vertical and horizontal arrangement. Slots 84 and 88 are 
preferably located beginning four inches from each vertical edge of panels 
82, so that two horizontally-abutted panels 82 will maintain the even 
eight inch spacing. 
The vertical joints formed between horizontally-abutting panels 82 are 
staggered so as to strengthen the wall. Since slots 84 are spaced at equal 
intervals, staggering the vertical joints still allows the same tie 
spacing and alignment. 
In some cases, it may be desirable to locate a tie directly on a vertical 
joint, so as to strengthen the joint against the outward pressure of the 
concrete. This may be accomplished by showing half the thickness of a slot 
84 on each vertical edge of panels 82. This allows the vertical edges of 
the panels 82 to form a tightly abutting vertical joint. The horizontal 
spacing of the slots 84 would still be maintained at eight inches, to 
maintain the modular arrangement of ties. 
The applicant has further discovered that the tongue and grooves shown in 
FIG. 2 and the castellations shown in FIG. 1 are not necessary to provide 
a strong interlocking system. Rather, the applicant has cut a slot 
one-half the depth of the tie end in each panel upper edge 86 and lower 
edge 90 such that one-half of the tie ends will rest in each of the 
abutting slots 84 (lower slot not being seen in FIG. 3). Thus, a single 
tie interlocks a vertically abutting pair of panels in vertical 
relationship and also maintains the horizontal alignment of the panels 82 
by virtue of the tight grip of paddles 56 and 60. The use of eight inch 
high panels along with eight inch horizontal spacing of the ties 
dramatically reduces the number of ties utilized to form a concrete wall 
as compared with the prior art system of FIG. 1. In fact, it has been 
found that the number of ties for a comparable wall is reduced by nearly 
fifty percent. Another advantage in using eight inch spacing is in the 
fact that normal four foot by eight foot sheets of material may be easily 
attached to the exposed paddles 60 without attempting to find ties that 
are appropriately spaced, which was necessary in the prior art. Since it 
is no longer necessary to machine each panel with a tongue and groove 
arrangement or castellations, or the like, the cost of the panel materials 
is also dramatically reduced. Common materials already available may be 
quickly and efficiently cut to the dimensions preferred without special 
tools for tongue and groove joints and the like. 
Use of an eight-inch-high panel has also proved to be extremely 
advantageous in allowing for a variety of wall thicknesses. The inventor 
has successfully poured eighteen inch thick walls utilizing the system 
disclosed in FIG. 3. A similar attempt with the inventor's tie fitted into 
the twelve inch height panels of the prior art failed. The twelve inch 
panels failed along a horizontal line centered between the top and bottom 
edges of the panel. This dramatic success allows for great versatility in 
the use of the concrete forming system of this invention. 
As shown in FIG. 3, the uppermost horizontal tier of panels have slots 84 
which are cut to a depth equal to the height of tie 34'. This allows tie 
34' to be inserted for a flush upper edge 86. A similar "full depth" slot 
is cut into the lower edge of the lowermost horizontal tier of panels, so 
that a flush bottom edge will allow the form system to rest flush on the 
ground surface. 
FIG. 3 also shows an end panel 92 created from three vertically-oriented 
2.times.12 boards 94 fashioned together with scrap lumber 96 as seen in 
the drawings. End panel 92 may be held in place against the vertical end 
of walls 81 and 83 in any conventional fashion. End panel 92 thus retains 
poured concrete between walls 81 and between end panels 92 at each end. 
The inventor has also found that an extra piece of polystyrene may be cut 
to a width equal to the distance between the vertical walls formed by 
panels 82. This extra piece may be inserted vertically so as to rest 
against the vertically-aligned ties 34', to thereby form an end panel. 
Once the concrete has hardened this end panel is removed after removing 
panels 82. Of course, the projecting ends of the vertical panels may also 
be cut flush to the concrete wall if the panels 82 are to be left in 
place. 
Referring now to FIG. 4, a third embodiment of the form system of this 
invention is designated generally at 98. Form system 98 includes a pair of 
parallel walls 81' and 83', composed of pairs of opposingly disposed 
panels 82' secured in spaced-apart parallel relationship by ties 34'. Form 
system 98 is intended to remain in place on the concrete wall once the 
wall has been poured and hardened, similar to the prior art systems. In 
order to create an exterior surface which does not have the protruding 
paddle 60, common in the embodiments shown in FIGS. 2 and 3, an additional 
longitudinal slot 100 is cut along the entire length of panel 82' along 
the upper and lower edges 86' and 90', respectively. Slots 100 are cut to 
the same depth as slots 84' and 88'. The crossed-slot formed thereby will 
allow paddle 60 to slide downwardly within slot 100 such that the outer 
surface of panels 82' are unobstructed by paddles 60. FIG. 5 shows an 
enlarged portion of one panel 82' and how tie 34 may be inserted within 
slots 84' and 100. As shown in FIG. 4, the outer surface of panels 82' is 
only broken by the narrow empty slots 84' and 88'. These slots may be 
easily filled to provide a completely smooth surface, if so desired. 
Although somewhat more time-consuming, individual T-shaped slots may be cut 
into each panel 82'. These T-shaped slots would be formed by a series of 
longitudinal cuts intersecting a series of transverse cuts, similar to 
those in the prior art. The individual T-shaped slots would avoid the 
necessity of filling the narrow empty slots shown in FIG. 4. 
The embodiment of FIG. 4 may also be modified so as to provide a tie 
directly on the vertical joints formed between pairs of horizontally 
abutting panels 82'. If a longitudinal slot 100 is utilized, it is only 
necessary to shave one-half the thickness of a slot 84' and 88' from the 
upper and lower locations on the vertical edges of the panels 82'. In the 
case where each T-shaped slot is formed individually, one-half of the 
longitudinal cut is formed in each vertical edge. The horizontal spacing 
of the ties would remain at eight inches, to maintain the modular 
arrangement of the ties. 
Referring now to FIG. 11, a third embodiment of a tie is designated 
generally at 102. Tie 102 includes the same elongated strap 52", diverging 
leg members 54", inner paddle 56" and legs 58" as the tie 34 shown in FIG. 
6. The main difference is in the use of an enlarged outer paddle 104 in 
place of the outer paddle 60 shown in FIG. 6. Enlarged outer paddle 104 
has a width of about two inches and a height of about six inches and has a 
rib 106 projecting perpendicularly from the outer face 104a, as shown in 
the drawing. Rib 106 is generally trapezoidal in shape with the base of 
the trapezoid located along the longitudinal center line of outer paddle 
surface 104a. Rib 106 also has a series of apertures 108 spaced along a 
line parallel to paddle 104 and generally centered along rib 106. 
Apertures 108 may be used to attach a vertical waler 110 to tie 102 once 
placed on a wall structure 70" as shown in FIG. 12. 
Tie 102 was designed specifically to be used in conjunction with panels 112 
which are twelve inches in height rather than the eight inch height of the 
panels of FIGS. 3 and 4 disclosed hereinabove. Tie 102 allows the ties to 
be spaced horizontally eight inches apart, the same as the embodiments 
shown in FIGS. 3 and 4, and also allows the use of a single tie to join 
two vertically abutting panel edges. Rib 106 provides the additional 
strength to outer paddle 104a to hold an additional vertical portion of 
each panel 112 against the strain of concrete poured therein. It has been 
found that the enlarged outer paddle 104 in conjunction with the remainder 
of a typical tie, as shown in FIG. 11, is sufficient to withstand the 
additional pressures exerted upon twelve inch panels in forming extra wide 
concrete walls. 
Referring to FIG. 12, a wall 70" is shown with panels 112 affixed thereto 
utilizing tie 102. A pair of 2".thrfore.4" vertical walers 110 are 
fastened to vertically-aligned ribs 106 using nails or screws affixed 
through apertures 108 into the walers 110. A trust joist 114 may also be 
utilized as a vertical waler, as shown in the drawing. A horizontal waler 
116 may be fastened to vertical walers 110 to provide horizontal 
alignment. 
It can therefore be seen that at least all of the above stated objectives 
are fulfilled by the above-described invention.