Note: Descriptions are shown in the official language in which they were submitted.
CONCRETE FORM AND RELATED METHOD OF CREATING A CANTILEVER
REVEAL
FIELD OF THE INVENTION
[0001] The present specification relates generally to concrete formwork, and
specifically to a
concrete form for the creation of a cantilever reveal in concrete stairs.
BACKGROUND OF THE INVENTION
[0002] Concrete is one of, if not, the most ubiquitous and enduring building
materials. It can be
used in many ways, for example, to create mass structures, such as dams, and
produce decorative
finishes, such as polished concrete surfaces. Regardless of the ways in which
concrete may be
used, a form or formwork is required to utilize concrete as a building or
ornamental medium.
[0003] Forms or formwork may be temporary or permanent moulds into which
concrete is
poured. Traditionally, timber, plywood or particle board is used to build, on
site, a mould that
defines a desired shape of the concrete to be poured within it. Accordingly,
the construction of a
form or formwork is specialized based on the dimensions and esthetic
requirements of the resulting
structure.
[0004] In the case of constructing concrete stairs, standard configurations of
forms and
formwork have been used for many years. Recently, however, it has become
fashionable to
incorporate specialized esthetic features, such as a "cantilever reveal",
which gives the illusion
that the concrete stair or set of stairs are floating. The reveal feature is
typically accomplished by
using standard forms or formwork for stairs and by either manually applying a
rigid item that is
the height of the reveal, during the pouring of concrete, to create the reveal
feature; however, this
technique does not allow the concrete technician to properly towel under the
rigid item to create a
smoothly finished reveal feature. These known processes are cumbersome and do
not accomplish
the sleek and tailored finish required to create the illusion of floating
stairs.
[0005] Accordingly, there is a need for improvements in the art to create a
cantilever reveal in
concrete stairs in an efficient and accurate manner.
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SUMMARY OF THE INVENTION
[0006] According to an embodiment of the present invention, there is provided
a concrete form,
comprising: a riser piece, including a top end and a bottom end; a cove piece,
the cove piece
including a distal end and a proximate end, the proximate end positioned on
the bottom end of the
riser piece at a perpendicular angle to the riser piece; and a reveal piece,
the reveal piece positioned
on the distal end of the cove piece projecting at a perpendicular angle to the
cove piece, such that
the reveal piece and the riser piece are parallel to one another.
[0007] According to a further embodiment, the present invention provides for
use of one or more
concrete forms to construct a cantilever reveal.
[0008] According to a further embodiment, the present invention provides a
method of
constructing a set of concrete stairs, the method comprising: constructing at
least one concrete
form, the at least one concrete form comprising, a riser piece, including a
top end and a bottom
end; a cove piece, the cove piece including a distal end and a proximate end,
the proximate end
positioned on the bottom end of the riser piece at a perpendicular angle to
the riser piece; and a
reveal piece, the reveal piece positioned on the distal end of the cove piece
projecting at a
perpendicular angle to the cove piece, such that the reveal piece and the
riser piece are parallel to
one another; affixing the at least one concrete form to at least one stringer;
and pouring concrete
within boundaries of the at least one concrete form and the at least one
stringer.
[0009] Other aspects and features according to the present application will
become apparent to
those ordinarily skilled in the art upon review of the following description
of embodiments of the
invention in conjunction with the accompanying figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The principles of the invention may better be understood with reference
to the
accompanying figures provided by way of illustration of an exemplary
embodiment, or
embodiments, incorporating principles and aspects of the present invention,
and in which:
[0011] FIG. 1 is a back perspective view of a concrete form according to an
embodiment;
[0012] FIG. 2 is a back view of the concrete form of FIG. 1;
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[0013] FIG. 3 is a side perspective view of the concrete form of FIG. 1;
[0014] FIG. 4 is a bottom perspective view of the concrete form of FIG. 1;
[0015] FIG. 5 is a back perspective view of the concrete form of FIG. 1;
[0016] FIG. 6 is a close up view of a series of concrete forms according to an
embodiment;
[0017] FIG. 7 is a top perspective view of the series of concrete forms of
FIG. 6;
[0018] FIG. 8 is a front perspective view of the series of concrete forms of
FIG. 6, with
environmental features removed;
[0019] FIG. 9 is a further top perspective view of the series of concrete
forms of FIG. 6, with
environmental features removed;
[0020] FIG. 10 is a close up, front perspective view of the series of concrete
forms of FIG. 6;
[0021] FIG. 11 is a perspective view of the series of concrete forms of FIG.
6, into which
concrete is being poured, with environmental features removed;
[0022] FIG. 12 is a perspective view of the series of concrete forms of FIG.
6, into which
concrete is being poured, with environmental features removed;
[0023] FIG. 13 is a perspective view of the series of concrete forms of FIG.
6, into which
concrete is being poured, with environmental features removed;
[0024] FIG. 14 is a close up, front perspective view of the series of concrete
forms of FIG. 6,
into which concrete has been poured and a concrete finisher is troweling under
one of the series of
concrete forms;
[0025] FIG. 15 is a perspective view of the series of concrete forms of FIG.
6, into which
concrete has been poured and a concrete finisher is troweling, with
environmental features
removed;
[0026] FIG. 16 is a perspective view of a series of finished concrete steps
featuring a cantilever
reveal according to an embodiment, with environmental features removed;
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[0027] FIG. 17 is a perspective view of a series of finished concrete steps
featuring a cantilever
reveal according to an embodiment, with environmental features removed;
[0028] FIG. 18 is a close up, perspective view of a series of finished
concrete steps featuring a
cantilever reveal, made using prior art devices and methods; and
[0029] FIG. 19 is a close up, perspective view of a series of finished
concrete steps featuring a
cantilever reveal, made using a concrete form similar to that of FIG. 1.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0030] The description that follows, and the embodiments described therein,
are provided by
way of illustration of an example, or examples, of particular embodiments of
the principles of the
present invention. These examples are provided for the purposes of
explanation, and not of
limitation, of those principles and of the invention. In the description, like
parts are marked
throughout the specification and the drawings with the same respective
reference numerals. The
drawings are not necessarily to scale and in some instances proportions may
have been exaggerated
in order to more clearly depict certain features of the invention.
[0031] According to embodiments as shown in FIGs. 1 to 17, and 19, a concrete
form may be
assembled as a single concrete form or a series of concrete forms to create a
mould into which
concrete may be poured in order to construct a single concrete stair or a set
of concrete stairs,
respectively, with a cantilever reveal. Cantilever reveals, such as cantilever
reveal 16100, 17100
and 19100, are an esthetic feature, which gives the illusion that a concrete
stair or set of concrete
stairs are floating.
[0032] A concrete form may be constructed from materials which provide the
mechanical
strength and durability to withstand the weight and moisture of poured
concrete. According to an
embodiment, concrete form 1000 may be made from wood, such as timber, plywood
or particle
board. In other embodiments, concrete form 1000 may be constructed of a
combination of wood,
aluminum, steel, other plastics, metals or composites or a combination of
suitable materials.
Manufacturing costs, desired lifespan, and reusability may also be
considerations in informing the
choice of materials and construction technique and other design choices of
concrete form 1000.
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[0033] According to an embodiment as shown in FIGs. 1 to 5, concrete form 1000
includes a
riser piece 1100, a cove piece 1200 and a reveal piece 1400. Riser piece 1100
is composed of a
plank of wood, such as timber, plywood or particle board and has a rectangular
shape. Riser 1100
may be of any width, as is known in the art, to withstand the weight of poured
concrete. Further,
riser 1100 may be of any length and height that corresponds with the desired
width and riser,
respectively, of a single concrete stair or set of concrete stairs.
[0034] Riser piece 1100 also includes a top end 1101 and a bottom end 1102, on
which a
proximate end 1202 of cove piece 1200 is affixed. Proximate end 1202 of cove
piece 1200 is
positioned on bottom end 1102 of riser piece 1100 at a perpendicular angle
1300 to riser piece
1100. Cove piece 1200 may be affixed to riser piece 1100 by any means known in
the art, such as
by use of nails, screws or adhesive compounds, that ensures secure and
impermeable attachment
of riser piece 1100 to cove piece 1200. Impermeable attachment is important to
ensure that
concrete poured into concrete form 1000 does not seep between riser piece 1100
and cove piece
1200, which would result in an irregular edge and may make removal of concrete
form 1000
difficult. Similar to riser piece 1100, dimensions of cove piece 1200 may be
of any length and
depth that corresponds with the desired width and cove, respectively, of a
single concrete stair or
set of concrete stairs. Further, perpendicular angle 1300 ensures that a riser
and cove of a concrete
stair or set of concrete stairs are constructed at right angles.
[0035] Cove piece 1200 also includes a distal end 1201, opposite proximate end
1202, on which
reveal piece 1400 is positioned. According to a preferred embodiment, reveal
piece 1400 and cove
piece 1200 are constructed from a single piece of material, such as aluminum,
steel or plastic that
is bent such that reveal piece 1400 projects at a perpendicular angle 1500 to
cove piece 1200 and
so that reveal piece 1400 and riser piece 1100 are parallel to one another.
Like riser piece 1100
and cove piece 1200, dimensions of reveal piece 1400 may be of any length and
height that
corresponds with the desired width and height of cantilever reveal,
respectively, of a single
concrete stair or set of concrete stairs. Further, perpendicular angle 1500
ensures that a cove and
cantilever reveal of a concrete stair or set of concrete stairs are
constructed at right angles, and that
a riser and cantilever reveal of a concrete stair or set of concrete stairs
are parallel.
Date recue/Date Received 2021-01-02
[0036] According to an embodiment as shown in FIGs. 6 to 15, a series of
concrete forms are
assembled to create a mould into which concrete may be poured to construct a
set of concrete
stairs, such as set of concrete stairs 16000, 17000 and 19000, with a
cantilever reveal, such as
cantilever reveal 16100, 17100 and 19100. The series of concrete forms are
comprised of at least
one of concrete form 1000. As is known to an individual skilled in the art,
dimensions of each
concrete form 1000 should be constructed and assembled relative to one another
to reflect the
desired rise (vertical height) and run (horizontal length) of a stair or set
of stairs. Accordingly,
when constructing concrete form 1000, rise and run measurements should first
be determined (and,
if necessary, in compliance with relevant jurisdictional building codes) to
ascertain the appropriate
dimensions of each stair's rise (i.e., the sum of the height of riser piece
1100 and reveal piece
1400) and run (i.e., the horizontal distance between each riser piece 1100).
[0037] Once concrete form 1000 is constructed, it is affixed to at least one
stringer 7000. Stringer
7000 may be cast-in-place or pre-cast concrete, stone, brick, masonry material
or wood structure
that supports concrete form 1000 when pouring concrete and, once the poured
concrete cures,
provides structural integrity to a concrete stair or set of stairs. According
to an embodiment, riser
piece 1100 of at least one concrete form 1000 is affixed to stringer 7000 by
way of screws and
reinforced by a plank of wood; however, stringer 7000 may be affixed to
concrete form 1000 by
way of any connection mechanism or material known in the art to provide the
appropriate strength
and durability to withstand the weight and moisture of poured concrete.
According to an
embodiment shown in FIG. 8, two concrete forms 1000 may each be affixed to one
of two stringers
7000 at one side and to the other concrete form 1000 on its other side,
thereby creating at least one
concrete stair with two cantilever reveals. According to a further embodiment,
two of three
concrete forms 1000 may be affixed to one of two stringers 7000 at one side
and to a third concrete
form on its other side, thereby creating at least one concrete stair with
three cantilever reveals.
[0038] Prior to pouring concrete into concrete form 1000, there are a number
of methods known
in the art to further support concrete formwork against weight of poured
concrete, to increase the
strength of concrete once it has cured and improve the removal of a concrete
form once concrete
has set. For example, at least one brace 13000 may be affixed to at least one
concrete form 1000
along a pitch of the set of concrete steps to support a weight of poured
concrete. Further, to provide
additional structural support and longevity to a cured set of concrete stairs,
prior to affixing at least
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one of concrete form 1000 to at least one stringer 7000, footings 6100 and
rebar grids 6200 may
be laid in accordance with known methods and using materials known in the art.
Concrete form
1000 may also be coated or covered with a liner or release agent 12000, which
prevents concrete
from sticking to concrete form 1000 and enables concrete form 1000 to be
easily removed once
concrete sets.
[0039] Finally, once all structural components and concrete form 1000 are
assembled, concrete
may be poured within the mould defined by the at least one concrete form 1000
and the at least
one stringer 7000. According to an embodiment as shown in FIGs. 11 to 15,
concrete 11000 is
transported to the site and shovelled into the boundaries defined by at least
one concrete form 1000
and at least one stringer 7000, filling the top most concrete form first and
then subsequent concrete
forms below it. Concrete 11000 may be comprised of any appropriate mixture and
proportion of
aggregate (e.g., sand, gravel, crushed stone, etc.), binder (e.g., cement) and
water known in the art
for constructing concrete stairs. As concrete is poured into each concrete
form, as is known in the
art, concrete form may be hammered or vibrated to drive out air bubbles and
then troweled to level
concrete, in order to create a smooth cantilever reveal. In contrast, use of
prior art methods and
devices, as shown in FIG. 18, result in a concrete stair or set of stairs,
such as concrete stair 1800,
that has a cantilever reveal 18100 that is bumpy, rough, and contains ridges
that diminish the
esthetic appeal and detracts from the "floating stair" effect. Once the
concrete is set up long enough
to support its own weight, concrete forms 1000 may be removed. Concrete may
still require further
time to cure fully into a set of concrete stairs, such as set of concrete
stairs 16000, 17000 and
19000, with a cantilever reveal, such as cantilever reveal 16100, 17100 and
19100.
[0040] Various embodiments of the invention have been described in detail.
Since changes in
and or additions to the above-described best mode may be made without
departing from the nature,
spirit or scope of the invention, the invention is not to be limited to those
details but only by the
appended claims.
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