Note: Descriptions are shown in the official language in which they were submitted.
CA 02225262 1997-12-19
Retainer for Poured Concrete Walls
Field of the Ilnvention
This invention relates to fasteners for use with insulating foam board used as
a form for
the pouring of concrete.
Background) of the Invention
In the pouring of concrete walls, such as for example foundation walls, what
is typically
done is to polar concrete footings on a suitable bed of gravel or the like.
These footings
extend upward to the level where the floor of the basement (or first storey,
if there is no
basement) will be. Two opposed forms are then erected which define between
them
a cavity into which concrete is poured. The forms are typically of metal or
wood, and
are of a standard size. Typically, the forms forming opposite faces of the
cavity are
joined together with pins (sometimes known as "ties") of metal or plastic. The
ties are
left in the concrete after it is poured, and form part of the wall.
Forms are typically supplied as a "system", which is a series of mating forms,
often
including forms of different sizes which are designed to be used with one
another.
There are a many systems in common use. They exhibit many different ways of
joining
the forms tol~ether edge to edge.
One of the most widely used systems of forms is composed of reusable plywood
sheets
of standard sizes, which are reinforced by having horizontal bands of metal
reinforcement spaced at standard intervals and extending across their width on
the face
not intended ~to contact the concrete. For example, standard sheets of plywood
for use
in the system may be 8 feet in height and 2 feet wide and of 1 114" thickness.
The
bands of metal are iron bands of about 3" in width and of the order of 118" to
114" thick.
They extend parallel to the 2 foot dimension of the sheet at arbitrary
distances from
each other and the 2 foot long edges of the board, and extend the full width
of the
CA 02225262 1997-12-19
-2-
board, from one of the edges of a long side to the other edge of a long side.
For
example, cornmonly there are four bands, having their mid-lines at 8", 28",
52" and 76"
respectively from the 2 foot edge which forms the bottom edge of the plywood
sheet
when it is assembled into a form,
Mounted on one end of each band, for example near the right edge of the face,
is a
pivotable hooking element, which pivots over and is retained by a post such as
a large
headed nail ~or screw or the like near the left edge of an adjacent like
panel. Similar
hook and post arrangements occur on the other bands, to hook adjacent panels
together to make a form. The hooking element also has at least one (usually
two) slots
to fit over and retain in place iron ties extending to the similar forms
making up the
opposite wall of the cavity into which concrete is to be poured.
It is also known to build forms of blocks of plastic foam which define the
cavity into
which the concrete is poured. The foam is usually foamed polystyrene ,
although other
types of foam plastic are sometimes used. The plastic foam can be left in
place after
the concrete is poured to function as insulation. Many form systems using
foamed
plastic are known. Representative ones are shown in U.S. Patent 4,889,310
(Boeshart)
and U.S. Patent 5, 140,794 (Miller). In the Miller patent, the forms are
joined together
by ties of wirE~. In the Boeshart patent, the ties are plastic.
Canadian published patent application 2,182,055 of the present inventor
provides a
forming system with conventional plywood forms on one side of the concrete
cavity and
foam panels on the opposite side. These are joined by ties which hold the foam
panels
in place while the cement is poured into the cavity. Certain of the ties
disclosed (either
alone or with plates as disclosed in that application) provide areas which
remain visible
on the surface of the insulated wall after the concrete has hardened. These
areas can
be used to anchor screws or nails to hold wallboard or strapping placed to
cover the
foam insulation.
CA 02225262 1997-12-19
-3-
It is sometimes desirable to use metal ties, instead of the ties disclosed in
application
2,182,055, vuith the invention of that application. This occurs particularly
where
relatively thick high concrete walls are being poured, putting larger than
usual stress on
the ties. However, such metal ties do not provide an area to anchor screws and
nails
to attach wallboard or strapping over the insulation on the finished wall.
It is sometimes desired, instead of using the invention shown in Canadian
patent
application 2,182,055, to use plywood forms, attached together by conventional
metal
ties, on both sides of the cavity. The insulating foam board is then placed
within the
cavity formed by the two sets of plywood forms, adjacent one set. The concrete
is
poured betwE~en the foam board and the other set of plywood forms. However,
when
this is done, there is no area on the surface of the insulation, after the
wall has been
poured and the forms have been removed, to attach screws or nails.
THE INVENTION
The invention provides a fastener retainer which is put in place extending
through a
foam insulation sheet into a cavity in which a concrete wall is poured
adjacent the foam
insulation sheet. After the concrete wall has been poured and has dried and
the
concrete forrns are removed, the fastener retainer remains with one end firmly
set in
concrete and the other end on the outer surface of the insulation, where
fasteners such
as screws or nails can be screwed into it. To the extent that the insulation
has not
bonded to thE~ concrete, the fastener retainer also retains the foam
insulation so it will
not fall off thE: concrete wall.
In a preferred embodiment, the fastener retainer also has clip means by which
it can be
clipped onto a metal tie extending through the insulation. In this embodiment,
the
fastener retainer has the added function of inhibiting movement of the foam
insulation
while the concrete is hardening.
CA 02225262 1997-12-19
-4-
A preferred embodiment of the invention will now be described with reference
to the
drawings in which like features of the invention bear like reference numerals
throughout
the several figures of the drawings.
Brief Description of the Drawings
Figure 1 is a perspective view of a preferred embodiment of a retainer in
accordance
with the invention.
Figure 2 is a perspective view of an alternate embodiment of the retainer.
Figure 3 is a perspective view of a concrete form assembly using the inventive
retainer.
Figure 4 is ~~ perspective view of an alternate concrete form assembly using
the
retainer.
Figure 5a, 5b and 5c are detail views of how various embodiments of the
retainer attach
to a tie.
Detailed De:~cription of the Invention
Figure 1 shows a perspective view of a preferred embodiment of a retainer 11
constructed in accordance with the invention. The retainer 11 has a base 10
which has
a flat front surface 9 suitable for the attachment of fasteners such as screws
or nails
and a back side 8 with structural ribbing (not shown) to increase its
strength. Holes
14 may be pr~wided in the base 10 to facilitate the attachment of screws or to
facilitate
the positioning of a staple for temporary positioning during form assembly.
An elongate arm 16 extends from the back side 8. Arm 16 is used to mount the
retainer to insulating foam board and concrete as will be explained in more
detail with
CA 02225262 1997-12-19
-5-
reference to Figures 3 and 4. Preferably, but not necessarily, means are
provided to
keep the retainer 11 lodged in a slit in a piece of foam board. Preferably
such means
are resiliently deformable grips 18 provided on arm 16. The grips are
preferably angled
with their oui:er ends toward base 10 so that they will deform when the arm is
moved
through a piESCe of foam board in the direction of arrow A and not impede
movement,
but so that they will impede movement when the arm is pulled through a piece
of foam
board in a direction opposite that of arrow A.
Near the end of arm 16 are means to anchor the retainer poured concrete once
the
concrete has hardened. These means are irregularities in the surface of arm 16
such
that, once concrete hardens in the irregularities, the arm will be permanently
attached
to the concrete. Preferred means are cut-out portions 20 which will become
filled with
the surrounding concrete to form an interlocking grip therewith to securely
keep retainer
11 within the concrete once it has cured. The cut-out portions are shown as
semi-
circular, but their shape is not important provided concrete can flow into
them when wet
and can harden there to prevent removal of the retainer once the concrete has
cured.
Ribs (not shown) can also be molded into the surface of arm 16 to strengthen
it as
well as produce further irregular surfaces to interlock with the concrete
which will in use
surround the retainer. A hole 22 can be provided in arm 16 if desired to
permit the
retainer to beg used as a tie between form pieces in a manner to be described.
The embodirnent of figure 1 has a resilient clip 51 integrally molded
therewith and
extending outwardly from arm 16. Clip 51 is composed of two clipping fingers
52
attached at their bases to arm 16 defining a cavity 50. The fingers can spread
outwardly
to receive a metal tie rod in cavity 50, and retain it by resilient pressure
once it is
received. Stops 54 are provided on the inside of fingers 52 to prevent the tie
rod from
sliding out of cavity 50. Cavity 50 extends through head 10, and slits 55 are
provided
between hea~~ 10 and fingers 52 so the fingers can flex relative to head 10.
Retainer 11 is preferably constructed from moldable plastic material which
provides
CA 02225262 1997-12-19
-6-
good structural strength, which can accept screws and nails without splitting,
and which
does not transfer undue amounts of heat across the foamboard insulation layer
when
the retainer is in use. It is also preferable that the plastic material not
become brittle
when cold, so that the retainers can be assembled in cold weather construction
conditions. Suitable materials can be selected from polypropylenes, or from
propylene
copolymers with ethylene or other compounds.
An alternativE~ embodiment is shown in Figure 2, and is numbered 11A. In
Figure 2, like
parts to the parts of Figure 1 are identified using the same reference
numerals as
Figure 1, and will not be further described. Instead of clip 51 and cavity 50,
the
embodiment of Figure 2 has a notch 56 cut out of head 10 and sized to permit
entry of
a metal tie used in the making of concrete forms. Figure 2 does not illustrate
head 10
as having holes 14, but such holes can be present if desired.
Figure 3 shows a perspective view of a concrete form assembly to pour a
concrete
building wall, The assembly has a rigid form 24 defining on side of a cavity
26. The
form is preferably the type of known plywood form illustrated in Figure 1 of
applicant's
published Canadian application 2,182,055. For clarity , only one piece of
plywood is
shown, but as known in the art, this is placed edge to edge with other pieces
of plywood
to form a form wall. A foam board 28 is in spaced relation to plywood form 24
to define
concrete cavity 26. It is illustrated with a tongue 30 which mates with a
groove on an
adjacent foamboard (not shown) to form a wall of cavity 26. The foam board is
used as
a form during concrete pouring and subsequently remains in place on the inside
of the
finished concrete wall as insulation. The spaced relationship between the
plywood form
and the foamboard is maintained by ties 38. Only two such ties are shown, but
in
practice there are several more along the edge of the foamboard bridging the
cavity 26.
Tie 38 has portion 39 extending on the other side of foamboard 28 from cavity
26. This
may be used to attach a water as shown in published application 2,182,055, and
may
be snapped off after the concrete has hardened as known in the art.
CA 02225262 2005-05-17
_7_
The retainer illustrated in Figure 3 is shown as 11B. It is the same as the
retainer 11A
illustrated in Figure 2, except that the notch 56 is deeper and is provided
with a
shoulder 58 to retain a metal tie. The retainer 11A of Figure 2 can be used
instead if
desired.
In the lower portion of Figure 3 a metal tie 38 extends across the cavity 26
and through
a slot 23 provided in plywood form 24. Tie 38 extends beyond the outer surface
of
plywood form 24. Tie 38 has mating means on the outer portion thereof
extending
beyond form 24 to be engaged by slot 40 provided in rotatable plate 42 which
engages
tie 38 by rotation of rotatable plate 42 about pivot point 44 as is well known
in the
construction trade. The foam board form 28 may include a precut L-shaped slot
46 into
which retainer 11 is slidably received. One such slot without a retainer is
shown for
clarity. It has a vertical portion 46A and a horizontal portion 46B. Retainer
11 B is slid
into the portion 46B with its arm 16 horizontal, and is then rotated to have
the arm
vertical in vertical portion 46A. This permits preassembly of the retainer to
the
foamboard and prevents retainer 11 B from dislodging or falling out of the
foam board
28 during handling. If grips 18 are provided (as is preferred), these assist
in keeping the
retainer in place relative to the foamboard.
If the retainer is to be assembled to a foamboard in a place where there is no
slot, arm
16 can be pierced through the foamboard. This can be facilitated by pre-
piercing the
foamboard with a sharp tool. For example, the uppermost retainer in Figure 3
has been
attached to the foamboard in this way.
One use of holes 14 is shown in Figure 3. A staple 60 can be inserted through
retainer
11 B into the foamboard and through a similar retainer 11 B on the foamboard
which will
be adjacent to it in forming a wall of cavity 36.
Th uppermost illustration of the retainer in Figure 3 shows a use of the
retainer to
replace tie 38, in a position (such as near the top of the foamboard) where
little force
CA 02225262 1997-12-19
_$_
is exerted on the tying element. Arm 16 is attached to a metal strip 32 by
means of a
wire 36 which is threaded through hole 22 and through a hole 37 in strip 32.
The other
end of strip 32 passes through the crack where two pieces of plywood abut, and
is
retained from pulling back into the cavity by a nail 34 inserted through a
hole 35.
Figure 4 shows a perspective view of a use of the retainer in a different
concrete form
assembly. In Figure 4, the foamboard is not used as a form wall. Instead,
there is a
second plywood form 48 spacedly deposed from a first plywood form 24. Foam
panel
28 is located between the two forms 48 and 24 and in contact with one of the
plywood
forms. Tie 38 extends through the outer portion of each plywood form 24 and 48
such
that a rotatak>le plate 42 can now be used on each side of the forms 24 and
48, as is
common with conventional plywood forms
The retainers in this embodiment pass through the foam, but not through the
plywood
48. The headl 10 is between plywood 48 and foamboard 28. If desired the
foamboard
can be millecl with depressions so that the surface 9 of head 10 will lie
flush with the
surface of thc: foamboard, but this is not necessary. The retainer used in the
topmost
position is the retainer 11 B as illustrated in Figure 3, and the lower
retainer is the
retainer 11 of Figure 1 The clip 51 (shown in dashed form, as it is concealed
in the
drawing by the foamboard 28) clips onto tie 38 to retain the foamboard in
position
relative to plyvuood 48 before the concrete is poured.
In either the embodiment of Figure 3 or Figure 4, the forms are assembled as
shown
in the figures, then the concrete is poured into the cavity. Once the concrete
hardens,
form 24 (Fig 3) or forms 24 and 48 (Fig. 4) are removed. Foamboard 28 remains
in
place as insulation for the concrete wall. The arm 16 of each retainer is
securely
attached in the hardened concrete, and is prevented from pulling out by
concrete in its
depressions 20. The retainers retain the foamboard against the concrete, and
also
provide surfaces 9 into which nails or screws can be attached to permit
attachment
wood strapping or the like to permit the attachment of wallboard or panelling
to cover
CA 02225262 1997-12-19
-9-
and conceal the foamboard and provide an interior wall.
Figure 5a shows a detail showing how the retainer of Figure 1 clips to tie 38
in a form
assembly of I=ig. 3 or 4. Tie 38 is of generally rectangular cross section,
but the section
changes along its length. Such ties are common articles of commerce. The tie
configuration is chosen so that there will be a clip-mating portion 57 which
is oriented
to be sliding~ly received within the tie-receiving slot 50 of the clip and
which has
orthogonal portions 60 and 61 disposed at either end thereof to prevent
relative
movement of fastener 11 relative to tie 38. The clip of Figure 5a also has an
end
portion 58 which extends outwardly from base 10 when the tie is mounted in the
retainer to co-act in known manner with the plate 42 and slot 40 (Fig 4) or to
attach a
water (Fig 3). The end portion will vary in length and configuration depending
on
whether the norms of Figure 3 or 4 are used.
Figure 5b shows the retainer 11A of Figure 2 and how it coacts with a tie 38
in a form
assembly of the sort shown in Figure 3 or 4. The end portion 58 of the tie
will be
shorter or longer as needed to accommodate whether it has to pass through a
plywood
panel 48 (Fic~ 4) or not (Fig 3).or not. Notch 56 fits over the portion 57.
And abuts
against a shoulder where the cross-section changes to cross section 61. In
use, portion
56 is chosen to be of sufficient length so that either the plywood (Fig 4) or
the water (Fig
3) pushes thE~ head 10 against the shoulder of portion 61.
Figure 5c shows an alternate embodiment of the clip portion 51 of retainer
11A.. In this
embodiment, the retainer 11A is provided with a pair of clipping fingers 52 A
which are
oriented to receive a portion 56A of tie 38 which is oriented vertically.
Now that the invention has been described, numerous substitutions and
modifications
will occur to one skilled in the art which are within the spirit and scope of
the invention
as described in the claims appended hereto.
