Note: Descriptions are shown in the official language in which they were submitted.
CA 02314612 2000-07-27
STI~.UCTURAL ELEMENT
Field of the Invention
This invention relates to structural elements that can be used to repair
and/or
protect a structural member such as a damaged joist or beam and/or be used to
protect such
members.
to Background of the Invention
Although vwious advanced materials have been produced, a large amount of
residential and commercial construction, both interior and exterior, still
utilizes wooden
joists and beams. Unfortunately, one of the problems structural members such
as wooden
joists and beams in an exterior environment, is that they are susceptible to
damage from
decay and rot, particularly such damage caused by or linked with moisture.
Although there are preservative treatments available for wood, the extra cost
for such treated wood is high. Furthermore, the treatment itself will have a
limited
lifetime, and eventually even a structural member made from treated wood will
start to rot
or decay. Furthermore, most of the wooden joists and beams currently installed
in
buildings today have wooden members that are untreated.
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CA 02314612 2000-07-27
For structural members such as joists and beams, an area that is particularly
susceptible to rot and decay caused by moisture is the top of the joist or
beam. It is there
where moisture tends to become trapped between the top of the joist or beam
and the
structure or components that are being supported by the structural member (for
example, a
deck). Moisture is unable 1:o easily drain away from between the top of the
joist or beam
and the bottom of the supported structure. However, often only a limited top
portion of a
beam or joist is in a damaged condition. Nevertheless, when replacing a deck
or other
supported feature, one will usually have to replace an entire beam or joist,
which may only
be damaged on the upper portion.
to
Another cause of damage to the top of joists or beams that support a deck,
occurs when the top decking must be replaced. In removing the decking
material, it is
quite common for the process to cause damage to the underlying beams and
joists as the
deck material is pried or disengaged from its supporting beams and joists. The
result is
15 joist/beam repair or replacement is commonly needed before a new deck
material is placed
down on the joists and beams.
Accordingly.,, it is desirable to have an efficient means of repairing and
protecting a structural member such as a joist or beam. Also, it is desirable
to provide an
2o efficient way of reducing the risk of wooden structural members being
damaged, either by
water or other ways in the fast place, by protecting these members from the
time they are
first installed.
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CA 02314612 2000-07-27
Summary of the Invention
According to one aspect of the invention, there is provided a structural
element for use with a structural member, said element comprising: a
longitudinally
extending body with an upper surface and a lower surface, and with a pair of
opposed,
spaced apart, downwardly depending flanges extending below said lower surface;
said
upper surface of said longitudinally extending body being generally flat, and
said lower
surface and said flanges being configured to be positioned above an area of a
structural
member; said side flanges being adapted to be secured to sides of said
structural member.
1o
According to another aspect of the invention, there is provided a structural
combination of a structural member and a structural element, said structural
element
comprising: a longitudinally extending body having an upper surface and a
lower surface,
and having opposed, spaced apart, downwardly depending side flanges extending
below
15 said lower surface; said structural element configured such that said lower
surface is
positioned above a first surface area of a structural member, said structural
member having
a pair of opposed side surfaces proximate said first surface area and each
said side surface
being oriented downward from said first surface area; said side flanges of
said structural
element being configured to be and being secured with one or more attachment
members to
2o the side surfaces of said stnictural member.
According to another aspect of the invention, there is provided a method of
repairing a damaged member with a repair element, said damaged member having
an upper
surface that is at least partially damaged, and two opposed sides, said repair
element
25 comprising: a longitudinally extending body having an upper surface and a
lower surface,
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CA 02314612 2000-07-27
and having a pair of opposed, spaced apart, downward depending flanges
extending below
said lower surface; said upper surface of said longitudinally extending body
being generally
flat, and said lower surface being adapted to be positioned above said damaged
member;
said side flanges being adapted to be secured to the sides of said damaged
member; said
method comprising the steps of: (a) placing said repair element in a position
where said
lower surface of said repair element. is over the upper surface of said
damaged member,
with a flange of said repair element being positioned adjacent to each side
surface of said
damaged member; (b) securing said flanges of said repair element to the sides
of said
damaged member.
According to another aspect of the invention, there is provided a method of
protecting a structural member with a structural element, said structural
member having an
upper surface and two opposed side surfaces, said structural element
comprising: a
longitudinally extending body having an upper surface and a lower surface, and
having a
pair of opposed, spaced apart, downward depending flanges extending below said
lower
surface; said lower surface being configured to be positioned to above a
surface of said
structural member; said side flanges being adapted to be secured to a side
surface of said
structural member; said method comprising the steps of: (a) placing said
structural element
in a position where said lower surface of said structural element is in an
opposed relation to
said surface of said structural member and with each flange of said structural
element being
adjacent to a side surface of said structural member, such that said lower
surface is above
said surface of said structural member; (b) securing said flanges to the side
surfaces of said
structural member to secure: said structural element to said structural
member.
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Brief Description of the Drawings
In figures which illustrate, by way of example only, embodiments of the
present invention:
Figure 1 is a cross-sectional, elevation view of a structural element;
Figure la is a cross-sectional, elevation view of the bottom part of an
alternate configuration for lower edges of the flanges of a structural
element;
Figure 2 is a perspective view of the structural element of Figure 1 shown in
use with a joist that has been repaired;
Figure 3 is a perspective view with a repair element shown exploded away
1o from a joist to be repaired;
Figure 4 is a side elevation view showing a structural element in use in a
structure;
Figure 5 is a cross sectional, elevation view of a first, alternate embodiment
of a structural element;
Figure 6 is a cross sectional, elevational view of a second alternate
embodiment of a structural element;
Figure 7 is a side elevational view of an alternate arrangement of a
structural
element in a structure;
Figure 8 is a cross sectional view at 8-8 in Figure 7.
Detailed Description of the Preferred Embodiments
With reference to Figures 1, 2 and 3, a structural element generally
designated 10 is illustrated. Element 10 has a longitudinally extending body
12 with a
longitudinally extending top portion 14 and a longitudinally extending base
portion 16. The
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CA 02314612 2000-07-27
body also has a pair of opposed longitudinally extending side walls 18 and 20.
Each side
wall 18 and 20 has a longitudinally extending lower flange portion (22, 24
respectively)
extending down from, and 'below, base portion 16.
Extending bEaween the upper portions of side walls 18 and 20 is a central
longitudinally extending wall portion 26 which stretches from the top portion
14 to base
portion 16 thereby creating two longitudinally extending hollow channels 28
and 30.
Channels 28 and 30 are continuous and provide for sealed channels that are
open only at their ends. Any moisture that does permeate into the channels 28
and 30, will
be able to see out of the element 10 at its ends, and in that regard, a small
gap could be
provided at the end between the end of the element and any abutting member.
In Figure la., a profile of an element 10a, of the bottom of flanges 22a and
22b is shown wherein lower edges 32a and 34a are perpendicular to the outer
faces 31a and
33a of the joist 36. In this embodiir~ent however, there will be a tendency
for water
droplets 35 to accumulate as shown. A more preferred embodiment of the
invention is
shown in detail in Figure 1, where the bottom edges 32 and 34 of flange
portions 22 and 24
respectively are angled downwardly from adjacent outer faces 31 and 33 of
joist 36 to the
outer faces 19 and 21 of side walls 18 and 20. Thus, in the embodiment of
Figures 1, 2
and 3, any moisture which drains down the outside faces of side walls 18 and
20, will tend
not to become trapped, as there is not the same right angled intersection of
edges 32a and
34a and the outside faces 31a and 33a of the joist 36a in element 10a.
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With reference to Figures 5 and 6, joists 136 and 236 are shown with
structural elements 110 and 210, respectively. Structural element 110 has
flanges 122a and
122b with lower edge faces 132a and 134a, respectively. Lower edge faces 132a
and 134a
has longitudinally extending relatively sharp tips 125 and 135, respectively.
Providing a
relatively sharp tip will tend to reduce the chance of water droplets 137
curling under and
accumulating along edge 132a and 1.34a to contact a side face of joist 136.
Rather, with a
relatively sharp tip, water droplets will tend to drop straight down, and if
touching the side
of joist 136 at all, will only contact sides faces of joist 136 lower down.
Structural element
210 as shown in Figure 6, is configured with relatively sharp tips on the
lower edges of the
flanges 222 and 224.
Element 10 c;an be used when a joist or beam is first being installed in the
structure or installed during repair, refitting or maintenance of a joist or
beam.
Element 10 could possibly be made from any one or more of metals,
plastics, fibers including wood, elastomers, ceramics, glass, concrete, or
composites or any
of the foregoing, so long as they are strong enough to withstand the load
applied from
above (eg. such as the weight of the deck being supported thereon). If element
10 is made
of a material such as wood, it will itself be subject to a high risk of rot or
decay. Also, the
2o example configuration of the elements, particularly with a configuration
such as element 10
and 110 shown in Figures 1, would be difficult to make from wood.
Nevertheless, using
an element 10 made of wood still provides advantages. For example, if repair
is necessary
to a combination of a joist/beam and an element 10, then repair of the overall
joist or beam
will likely not be necessary; the only repair that is likely to be needed is
the element 10.
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However, enhanced benefits are obtained if element 10 is not made of wood
of a material which in addition to being strong enough to support the required
load, is also
a material which is not particularly susceptible to breakdown or damage, such
as damage
due to water. Also, in most residential and commercial construction, it is
more preferable
if element 10 is made from a material which is relatively easily and
efficiently formed into
a desired configuration, is relatively inexpensive, and is not too heavy.
Composite
materials are therefore quite suitable and these materials can be extruded to
the desired
configuration for an element 10. One of the most advantageous composites for
element 10
1o is to make it from a composite wood material. Such a product can be made by
combining
wood fragments such as wood flakes, strands, particles, chips and fibers with
a resin,
particularly a thermoplastic resin, and then extruding the mixture through an
extruding
mould, and allowing the extruded product to fully set. Examples of suitable
resins include
polyethylene and polypropylene. Some examples of a composite wood material are
15 disclosed in U.S. Patent no. 3,888,810 to Shinomura, the contents of which
are hereby
incorporated by reference. The composite wood element 10 could be extruded
using a
technique similar to that described in U.S. patent no. 5,234,652 to Woodhams
and U.S.
Patent no. 5,783,125 to Bastone et al., the contents of which are hereby
incorporated by
reference.
In Figure 3, a typical wooden joist 36, such as a two by ten joist, is shown.
Along part of the top surface 40, and extending down part way into the joist
36, is a rot or
decay area 38. While not necessary, when repairing such a joist 36, prior to
mounting
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element 10 on the top of joist 36, decayed area 38 is preferably removed from
the joist, for
example by cutting it out with a saw or similar tool.
As illustrated in Figure 2, the lower face 42 of base 16 of element 10 when
in place, is positioned on top of top surface 40 of joist 36 shown in Figure
2. Once element
is positioned on top of joist 36, the element can be secured by attachment
means or
members such as bolts, staples, screws, spikes, or nails 62 driven or passing
through the
lower flange portions 22 and 24 of side walls 18 and 20, respectively or other
suitable
attachment means, to attach the flanges to the sides of the joist 36.
The channel 50 between the edges 32 and 34 of the outer flange portions 22
and 24 and the outside side face of the joist 36 is maintained, even once the
flanges are
secured in place, as this allows water to drain away from the contact area
between the inner
face of the flanges and the side face of the joist.
It will be aplneciated that when in place, as shown in Figure 2, element 10
provides a barrier between the top of the joist and the structure that is
being supported;
element 10 tends to insulate the top of the joist 36 from the structure or
members that it is
supporting.
Turning to Figure 4, an example of use of a structural element 10 in a deck
structure is shown. Decking 60 is shown supported by a plurality of joists 36
each having
an element 10 secured on top of the joist 36 (only one joist and element 10
can be seen in
the side view). Decking may be any known decking material including a
composite wood
CA 02314612 2000-07-27
decking such as is disclosed in US design patent no. 423116 issued April 18,
2000. Nails
62 or other attachment members ca~i be secured through the decking 60 into the
top 14 of
element 10. Thus, if there is any prospect of any moisture leakage from the
deck surface,
it is more likely to find its way into longitudinally extending channels 28
and 30. In any
event, moisture will be unlikely to reach the top portion of joist 36. Thus,
the top portion
of joist 36 is essentially insulated from moisture at, or passing from, the
lower surface of
deck 60.
With reference to Figure 4, it can be seen that element 10 can stretch the
to entire length of the joist 36., The joist 36 shown, is one of several such
joist in horizontal
alignment and being supported between two walls 44 and 46. Other arrangements
are of
course possible, as known in the art, for supporting decking. For example, the
joists may
be interconnected by supporting beams which themselves are supported on posts.
15 To maintain a level deck surface with respect to several adjacent joists
36,
either elements 10 will havE: to be added to each of the joists or the joist
being repaired will
have to have its top portion removed along its length so that the top surface
of element 10
coincides with the top of the joist being repaired and adjacent joists. To
provide for future
protection of all joists, it is usually preferred to provide all joists in a
structure with
20 elements 10.
Element 10 could be employed over just part of a joist or beam; but this
would likely require a portion of the member be removed, to ensure a
continuous flat upper
surface along the entire length of the structural member.
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As mentioned above, it is possible to utilize elements 10 when a set of joists
or beams or both are initially being installed, by providing for elements to
insulate the tops
of the joists or beams from the above supported structure. Thus element 10
will serve to
protect the joists and beam,. and reduce the risk of damage occurring, such as
from
moisture. Also, when replacing a deck supported by the joists/beams, having
element 10
installed will protect the joist or beam when the old deck is being removed,
and only one or
more elements 10 will have to be replaced.
1o With reference again to Figures 5 and 6, it will be appreciated that the
addition of an element 110 onto a joist or beam 136 will raise the overall
height of the top
surface. By way of example, the addition of element 110 on top of a joist
might raise the
top surfaces by about 1 lh inches. In some circumstances, however, there may
be
constraints which do not permit this additional height. Accordingly, the
element 110 could
be cut along line x-x shown in Figure 5 along its length to produce in element
210 as shown
in Figure 6. Alternatively, element 210 may be extruded in this specific
configuration. For
element 210 the only additional height above the top of the joist or beam 236
is the
thickness of the material "w" which might for example be 1/4 inch. This
reduced thickness
can perhaps be more easily be accommodated. Element 210 can be used in
conjunction
2o with a composite wood decking 300, such as the decking disclosed in U.S.
design patent
no. 423116 issued April 18, 2000 to Gregori, the contents of which are
incorporated by
reference. Composite wood decking is often not as deep as standard wood
decking and so
using it in combination witr~ an element 210 may result in no overall increase
in height of
the top surface of the deck.
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Element 210 does not provide all the benefits of elements 10 and 110, in that
it does not have elements such as channels 28 and 30. Therefore, when decking
is attached
to the element 210 through top portion 216, it is possible that the nails or
other attachment
members may pass into joist or beam 236. Thus, a little moisture may be able
to pass to
the top of the joist or beam 236. Nevertheless, element 210 can still provide
a significant
degree of protection for the joist or beam 236.
With reference to Figures 7 and 8, a structural element 410 similar to
1o element 10 is shown in use in a deck structure 411 adjoining a wall 415 of
a building.
Structure 411 comprises decking 460 supported on a series of spaced apart
joists 436 each
having a structural element 410 positioned proximate its upper surface 492.
Joists 436 are
supported at one end by conventional attachment (not shown) to wall 415 and
supported at
the opposite end by a beam 431 comprising two beam components 431a, 431b, such
as for
example two, 2 x 8 lengths of wood, nailed together. The beam 431 is supported
by a
plurality of posts such as post 429.
The structural element 410 has a bottom surface 490 which is positioned in
opposite but spaced relation to top surface 492 of joist 436. In this
embodiment top surface
492 is horizontally oriented, whereas bottom surface 490 of structural element
410 is sloped
downward from left to right in Figure 7. This orientation is also illustrated
in the elevation
view in Figure 8 where rear edge 480 of the top surface 481 of element is
positioned above
median edge 482 (the decking 460 is not shown in Figure 8). Thus, top surface
481 of
element slopes downward from rear edge 480 to front edge 486. In yet another
alternate
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embodiment (not shown), the bottom surface 490 of each element 410 could rest
on top
surface 492 of each joist 436 at their front edges.
The bottom surface 490 of element 410 is maintained in spaced relation to
top surface 492 of joist 436 by attachment devices such as for example nails
444. The
spacing of nails 444 will be selected to ensure that it can properly support
the loads on the
structural element including the load from decking 460.
By being able to vary the orientation of elements 410 relative to their
1o respective joists 436, the elements 410 are able to vary the orientation of
the upper surface
supporting the decking 460.. Thus, as shown in Figures 410, elements 410 can
be oriented
to ensure that water on decking 460 will drain away from wall 415. It will,
however, be
appreciated that within limits resulting from the size and configuration, the
orientation of
elements 410 relative to their respective joists 436 can be varied within a
range, to provide
a desired orientation for the upper surface.
The above described embodiments are intended to be illustrative only and in
no way limiting. The described embodiments of carrying out the invention are
susceptible
2o to modification of form, size, arrangement of parts, composition and
details of operation.
Rather, it is intended to encompass all such modifications within its scope as
defined by the
claims. For example, the structural elements of the present invention could be
used in
conjunction with other structural members, in addition to beams and joists,
including but
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CA 02314612 2000-07-27
not limited to roof rafters and posts. Also, the side flanges do not have to
be continuous
along the entire length of the structural element.
Although many of the applications for such structural elements are for
exterior construction environments, these structural elements are also
applicable to interior
environments. For example, although there may be little risk of damage to
beams and joist
from moisture inside a particular building, the use of such structural
elements can still be
beneficial. For example, in interior applications, such structural elements
can, as in
outdoor applications, provide a leveling or orienting function, as described
above.
14
