Note: Descriptions are shown in the official language in which they were submitted.
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FLASHING
TECHNICAL FIELD
Flashing is disclosed which finds particular use in
the construction industry, primarily for covering members
such as joists, beams, bearers, wall plates, rafters and
the like.
BACKGROUND ART
Flashing is used in the construction industry to
provide a barrier against the passage of moisture into and
beyond joists, rafters, beams, bearers, wall plates and
the like, especially where such members are formed from
materials susceptible to moisture such as timber.
Known flashing includes metal strips or metal-
containing sheets which are cut and positioned in relation
to the member. It is also known to use adhesive tape in
the place of metal flashing.
US 5,148,644 discloses a covering strip of rubber or,
plastic. At column 2, lines 1&2 it is stated that the
strip is dimensioned so that the distance between the side
portions substantially corresponds to the width of a
wooden member on which the strip is placed.
SUMMARY OF THE DISCLOSURE
'In a first aspect there is provided flashing
comprising an elongate body for overlying a member, and
legs extending for at least part of the body length and
protruding from either side of the body, the flashing
having a configuration prior to overlying the member
whereby one or both legs is/are biased towards a
respective member side when positioned thereat.
Thus, the flashing can be provided with an in-built
bias which enables it to better grip onto and/or locate on
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the member on which it is placed. This bias can be pre-
configured within the flashing body to then be transferred
to the legs when the flashing is placed on the member,
and/or can be pre-configured within either one or both
legs. In one form, both legs may have such bias.
In addition, whilst the legs may be spaced at
approximately the width of a member (eg. the flashing can
be supplied with leg spacings corresponding to one or more
standard member widths), the legs may also have a spacing
that is greater than or, in the case of an elastomeric
flashing, slightly lesser than the member width and yet
still be configured to grip onto, the member.
In one form the body can be provided with eg. a
contoured profile. For example, the legs may extend
inwardly from a concave surface of the body. Then, when
the flashing is located on the member, the body can assume
a generally flat configuration. The contoured profile
provides one means by which bias can be pre-configured
within the flashing.
In one form the flashing is formed from an
elastomeric material. Use of an elastomeric material
provides for noise reduction (especially when used on
metal members such as metal joists) and can provide for
impact absorption between adjacent members (ie. between
which the flashing is located). In addition, when nails
or screws are driven through the flashing, the elastomeric
properties enable the elastomeric material to grip around
the nails or screws, thereby preventing water, moisture,
liquid and dust movement therepast. The use of an
elastomeric material can also enhance the in-built bias of
the or each"leg.
The term "elastomeric" is intended to include a broad
range of polymers having resiliency and/or shape memory,
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and includes natural and synthetic rubbers such as EPDM
rubber, polymeric resins having flexibility and resiliency
such as ABS resin and other butadiene and styrene polymers
and co-polymers, nylons etc. EPDM rubber is particularly
useful because it has excellent UV, ozone and chemical
resistances, and is long-ageing. In addition, it is
resistant to most paints, lacquers, oils, solvents, acids
and cleaning agents.
The term "member" as used herein includes joists,
beams, bearers, wall plates, rafters, battens and the
like.
In a second aspect there is provided flashing
comprising an elongate body for overlying a member, and
legs protruding from either side of the body and extending
for at least part of the body length, wherein one, some or
all of the legs are detachable from the body along a
respective line of severance.
In a third aspect there is provided flashing
comprising an elongate.body for overlying a member, and
wings extending laterally from either side of the body and
extending for at least part of the body length, wherein
one, some or all of the wings are detachable from the body
along a respective line of severance.
By providing for leg and wing detachability, various
flashing shapes can be created which can allow for
accommodation of various other adjacent members in
abutting or closely positioned relationships. For
example, when all legs and wings are detached, the
resultant flashing may simply comprise the elongate body,
or when one of the legs and one of the adjacent wings are
detached and the flashing is applied to a first member, an
adjacent second member can be butted right up against the
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first member where that leg and wing have been removed,
etc.
In one form the flashing comprises two legs extending
for the entire length of the body on opposing sides
thereof, although a plurality of discrete legs arranged
along part or the entire length of the body on opposing'
sides thereof can also be provided.
In one embodiment, prior to positioning the flashing
on the member, legs on opposing sides of the body project
generally towards each other. In this regard the flashing
may be extruded or moulded so that the legs in the
finished configuration project generally towards each
other and so that the flashing is manufactured with an in-
built bias. Thus, when the legs are positioned on either
side of the member, they are biased towards that
respective side. This enables the flashing to grip onto
the member, making it easier to use and tending to prevent
its inadvertent removal. For example, when the flashing
is used in an inverted or vertical configuration, the legs
grip onto the member and prevent the flashing from
dropping off the member.
In addition, by providing legs which extend for the
entire length of the body on opposing sides thereof the
flashing can prevent stain marks from promulgating down
the side of the member to which the flashing is attached
(eg. resin stains, water stains etc that emanate from or _,
occur on timber members, or from seepage from overlying,
abutting or adjacent members etc).
In another embodiment the flashing further comprises
wings extending laterally from the body beyond the legs
(ie. the wings can be provided in addition to the legs).
Again, the wings may extend for the entire length of the
body on opposing sides thereof, although a plurality of
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discrete wings can be provided for part of or for the
entire length of the body on opposing sides thereof. The
wings enable the flashing to overlap adjacent members, and
can also overlap adjacent flashing etc to provide for a
more comprehensive barrier against moisture, dust, noise
and the like.
A line of severance can also be provided along and
adjacent to where each wing is attached to the body to
enable wing detachment. In other words, a discrete or an
entire length of the wing can be removed to enable
positioning of the member in close proximity to other
members and to enable the abutment of adjacent members
etc.
The wings may have an elongate rectangular shape and
can respectively be joined to the body along opposing
elongate sides thereof. In a further variation, each wing
can taper, from a relatively thicker section where it is
connected to the body to a relatively thinner remote end
(ie. the wing having a decreasing cross-sectional
thickness out to its remote end). This tapering
configuration can. reduce any distortion between flashing
heights in adjacent members where the wing overlaps
adjacent flashing (eg. of an adjacent member). The wings
can also be fastened directly or indirectly to an adjacent
member (eg. by nailing, screwing, adhesive, etc).
In one embodiment a line of severance is provided
along and adjacent to where each leg attaches to the body
to enable all or any of the legs to be detached from the
body as appropriate, in a similar manner to wing
detachment. Again, detaching of one or more legs allows
for close positioning or abutment of adjacent members etc.
The body may have an elongate rectangular shape so
that it can be positioned along a corresponding
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rectangular face of a member (eg. an upper face of a
joist, bearer etc). The legs can also have an elongate
rectangular shape and be respectively joined to the body
along opposing elongate sides thereof (eg. so that they
can run along corresponding rectangular side faces of a
member such as a joist). Each leg may also taper, from
where it is connected to the body to a remote end, or can
be provided with a constant thickness therethrough.
In a fourth aspect there is provided an arrangement
between first and second members wherein flashing as
defined in the first, second or third aspects is mounted
to an in-use upper surface of each member such that the
flashing of one member overlaps the flashing of another.
In the fourth aspect selected wings) andjor legs)
of the flashing of each member can be removed to reduce or
eliminate the degree of flashing overlap.
The arrangement may be defined as a joint (eg. a butt
joint) between the first and second members.
BRIEF DESCRIPTION OF THE DRAWINGS
Notwithstanding any other forms which may fall within
the scope of the flashing as defined in the Summary,
specific flashing embodiments will now be described, by
way of example only, with reference to the accompanying
drawings in which:
Figures 1A, 1B, 1C show respectively plan, end and
underside plan views of an end section of a flashing
embodiment;
Figure 2 shows a perspective view of the flashing end
section of Figure 1;
Figure 3 shows a side elevation of the flashing end
section of Figure 1;
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Figure 4 shows an enlarged end elevation similar to
Figure 1B and illustrating lines of severance in the
flashing in greater detail;
Figures 5A-5F show end elevations of various flashing
configurations in which parts of the flashing have been
detached for different applications; and
Figures 6-15 show various in-use configurations of
the flashing of Figures 1-5.
DETAINED DESCRIPTION OF SPECIFIC EMBODIMENTS
Referring firstly to Figures 1 to 3, a flashing
embodiment 10 comprises an elongate body portion 12 having
a centre line 14 formed (eg. indented or raised) or
printed thereon to enable centring of the body portion on
a member such as a joist or the like. The centre line 14
also provides a guide for accurate nailing/screwing of
overlying members (eg. decking).
Projecting laterally from respective longitudinal
sides of the body portion 12 are two wing portions 16.
Each wing portion is attached to the body portion via a
respective raised region 18, which supports flexure of the
wing portion with respect to the body portion.
It will also been seen that each wing portion tapers
in thickness from the raised region out to a free edge
thereof. Thus, adjacent to its free edge, each wing
portion is relatively thin, and this allows it to overlap
adjacent flashing etc (as described below). In addition,
each wing portion may extend for the entire length of the
body portion, or may be provided as a series of discrete
wing portions spaced along a respective longitudinal side
of the body portion. As a further alternative, discrete
wing portions can be cut, torn or severed from a larger
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length of wing portion in use, again depending on the
application.
Extending downwardly from adjacent longitudinal sides
of the body portion are two leg portions 20. Each leg
portion is connected to the body portion adjacent to a
respective raised region 18, and each leg portion subtends
an acute angle a (Figure 1B) with the body portion. Thus,
prior to locating the flashing on a member, and as can be
seen in Figure 1B, the leg portions tend to generally
point towards each other, which provides the flashing with
a pre-application configuration that enables it to grip
onto a member, as described below.
Alternatively, one of the legs may extend generally
orthogonally from its connection to the body portion, and
yet the other leg when subtending an acute angle can still
provide the flashing with a pre-application configuration
that enables it to grip onto a member.
Each leg portion can also slightly taper in
decreasing thickness from the body portion out to a free
edge thereof. This provides the leg portion with a
greater degree of stiffness adjacent to the body portion
and relatively less stiffness away from the body portion.
This also assists with maintaining an in-built bias in the
leg portion orientation to the position as depicted in
Figures 1B and 2.
Again, each leg portion can extend for a full length
of the body portion, or can be provided as a series of
spaced apart discrete leg portions along the length of the
body portion. In addition, these discrete leg portions
can be formed by severing, tearing or cutting sections of
a leg portion from the remainder of the leg portion
length.
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As best shown in Figures 1B and 4, the body 12 is
provided with a contoured profile. The legs 20 extend
inwardly from a concave surface 21 of the body. Then, when
the flashing 10 is located on a member, the body 12 will
assume a generally flat configuration (Figure 7). However,
the previously contoured body profile now provides a bias
which is transferred to the legs 20 so that they grip onto
respective member sides.
In an alternative arrangement the body 12 can be
supplied in a generally flat configuration, with one or
typically both legs 20 generally pointing to each other.
Then, when the flashing 10 is located on a member, the
bias is provided by the one or both legs, so that the legs
then grip onto the respective member sides.
As best illustrated in Figures 1C and 4, a line of
severance 22 is provided where the wing portion 16
connects to raised region 18. This enables each wing
portion to be partially or completely severed, cut or torn
from the body portion (eg. as shown in Figures 5A, 5B, 5C,
5F and 13). Similarly, a line of severance 24 is provided
where each leg portion connects.to the body portion 12.
Again, this allows each leg portion to be partially or
completely severed, cut or torn from the body portion (as
shown on Figures 5A, 5D, 5E, 5F and 14). In addition, the
lines of severance 22,24 need not be at the connection
points of the wing/leg portions to the'body portion and,
for some applications, could instead be located partway
along the wing/leg portions.
Referring now to Figures 5A to 5F, it will be seen
that a number of different wing portion and leg portion
detachment scenarios are possible. Each of these allows
the flashing to be used in parallel or in various angular
relationships with adjacent flashing on adjacent members
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and allows for various other positional arrangements of
the flashing on a member to which the flashing is mounted.
Referring now to Figure 6, flashing 10 in accordance
with the present invention is shown positioned on a member
in the form of a joist J, an end of which is butted to a
wall W (which may also be a beam etc). The joist J also
sits on top of a member in the form of bearer B. As can
be seen, part of each of the leg portions 20 is cut or
torn away, or removed, to define an end region 26 of the
body portion 12. This end region together with the wing
portions 16 lap upwardly along the wall W as shown.
This lapping provides a barrier to water, moisture,
liquids, dust etc at the joint of joist J to wall W. The
end region can also be sealed against the wall (eg: by
nailing, screwing, adhesive etc). In addition, the wing
portions 16 at the end region overhang laterally either
side of the joist to provide a.covering effect to the
joint.
As best shown in Figures 7 and 8, when the flashing
10 is mounted to a joist, the leg portions 20 are urged
outwardly by respective sidewalls of the joist J. Because
of a pre-configured internal bias in the flashing against
such outward movement, the leg portions grip onto either
side of the joist. This then enables placement onto the
flashing of overlying members (eg. battens, decking etc)
and fastening of these members to the joist with less
likelihood of flashing displacement.
Referring specifically to Figure 7, it will be seen
how the flashing 10 covers and protects the top face of
the joist J, with the wing portions overhanging the joist
on either side to prevent moisture (eg. rain etc), fluid
seepage and dust etc falling onto the top and sides of the
joist. In addition, it will be seen how the leg portions
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20 (biased outwardly by the respective joist side faces)
grip on to the joist to hold the flashing firmly in place.
If desired, adhesive can also be applied between the
flashing and the joist.
When an overlying member (eg. decking, floorboards,
panels etc) is positioned on top of the flashing, nails or
screws can be driven through the flashing. Where the
flashing is formed from elastomeric or deformable
material, it tends to grip around the side of the nail or
screw, thereby also preventing the passage of moisture,
dust etc between the flashing and nails/screws and towards
the joist. The flashing can thus act as a complete
waterproof barrier and can prevent rotting, warping, etc
of the joist. The flashing can also prevent moisture
vaporisation between the joist and flashing which can
otherwise lead to bubbling, buckling etc.
Referring now to Figure 8, parallel joists, J and J'
are shown. In this embodiment the left-side flashing 10
has one of its wing portions removed (in the manner as
shown in Figure 5B) enabling the adjacent right-side
flashing 10''to overlap in the region shown by arrow O.
As also shown in Figure 8, the leg portions located
between the adjacent joists can be compressed together
when the flashing is formed from an elastomeric or
deformable material.
Because the wing thickness tapers out to its remote
edge, the thickness of the overlap also accordingly
tapers. This means that, for any overlying member (eg.
batten, floorboard etc) there is not an undue or overly
uneven overlap to underlie that member in use. For
elastomeric flashings, this more minimal degree of
thickness of overlap may also be readily and easily
compressed in use.
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The overlapping of adjacent flashings further
provides greater sealing against the passage of moisture,
dust between the adjacent joists, which has many
advantages. In addition, it provides for increased
support for overlying members to enhance impact
resistance, sound absorption, cushioning etc.
Referring now to Figure 9, an arrangement for
abutting perpendicular joists J and J' is depicted (ie. a
so-called "butt" joint). In this arrangement, the joists
are connected by a screw or nail plate P. The left-side
joist J has a flashing 10 mounted thereto, similar to the
flashing shape of 5B. The left-side flashing 10 has one of
its wing portions removed to enable the left-side joist to
be positioned in close facing relationship (or abutment)
to a wall W. The flashing of Figure 5A can also be
employed in this regard.
The right-side joist J' employs a flashing 10' shaped
similarly to that shown in Figure 4. As can be seen, the
left-side flashing has a wing portion that overlaps the
right-side flashing to provide a moisture etc barrier at
the intersection of the two joists. Decking members D can
then be positioned over the two joists and fastened down
onto them (eg. by screws or nails) which can extend
through the respective flashings. The decking D can also
compress against the overlapping wing portion of the left-
side flashing. Again, because of its tapering thickness,
the wing portion can be compressed by decking D so that
adjacent decking members can be levelled as depicted.
Figure 10 shows an arrangement of perpendicular
joists J and J' similar to Figure 9, but where a section
28 (shown in phantom) of the overlapping wing portion 16
has been cut, torn or detached along the line of severance
22 and also cut from a remainder of the wing portion 16
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(eg. where no overlap of the wing portion is required or
desired). This arrangement can be employed eg. where
moisture etc ingress is not critical, such as in indoor
applications.
Referring now to Figure 11, an arrangement is
depicted where the joist J abuts perpendicularly a plate
member PL. Once again, sections of leg portions 20 have
been removed adjacent to the plate PL to enable the body
portion 12 and lateral wing portions 16 to lap over a top
surface of the plate PL. Decking D can be then be
positioned on top of the joist at the intersection of the_
joist with the plate.
Referring now to Figure 12, the close positioning of
a joist J against a wall W whilst resting on a bearer B is
depicted. The flashing can employ a shape similar to that
shown in Figure 5B. The location of one of the leg
portions 20 between the joist and the wall prevents the
ingress of moisture, dust etc at region E. The over-
hanging of wing portions 16 prevents moisture, seepage etc
running down the side of joist J, the moisture dropping
off the flashing at region G. In addition, the provision
of the right-side leg portion enables the joist to be
painted, or coated with a sealer, and thereby prevents any
overlying members (such as decking, floorboards etc) from
being inadvertently coated with the paint, sealer etc.
Thus, the bottom tip of the leg provides an edge I to
enable paint "cutting-in".
As stated above, Figure 13 shows the removal (eg. by
cutting, tearing etc) at the line of severance 22 of one
of the wing portions. Figure 14 shows the removal at the
lines of severance 24 of two of the leg portions.
Referring now to Figure 15, a flashing 10 similar to
that depicted in Figure 5E is shown positioned on a joist
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J. In this application, both leg portions 20 of the
flashing have been removed so that the flashing can be
positioned on top of the joist and so that the wing
portions 16 overhang either side of the joist. This
arrangement can be employed where it is not necessary for
the flashing to grip onto the joist (eg. where it is not
critical that the flashing be in perfect alignment at a
central position on top of the joist). Alternatively, to
maintain a central alignment, the flashing can be
adhesively fixed to the joist or can be nailed or screwed
thereto, prior to then attaching overlying members to the
j oist .
Whilst in Figures 6-12 and 15 the flashing has been
described with reference to its use on joists, it should
be appreciated that the flashing can be used with many
different types of members including beams, bearers,
rafters, battens, purlins, gurts, uprights etc.
Whilst typically the flashing is formed from an
elastomeric polymer, in some applications it may be formed
from more.rigid polymers or other materials. Thus, it can
be extruded or moulded and supplied in easy to use rolls.
As stated above, the flashing provides a number of
key features. These include:
~ The capacity of the flashing to cover and protect
the upper surfaces of joists, beams and other members
(especially timber joists and beams) to prevent rot,
splitting, swelling, staining, discolouration, etc from
moisture and other liquid passage, dust etc.
~ The in-built bias in the flashing which enables
the leg portions to grip onto the side of a member, thus
enabling the flashing to be used in a number of
orientations, including inverted orientations.
~ Detachability/severability of the leg portions
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and wing portions of the flashing, which enable it to be
used in a variety of different applications, some of which
have been described above with reference to Figures 5-15.
~ The capacity of the flashing to grip onto nails,
screws etc inserted therethrough, to waterproof and
prevent moisture, dust and the passage of other matter
between the flashing and the nail/screw.
~ The capacity of the flashing to compress to enable
overlapping of adjacent flashings without affecting
respective levels of overlying members (such as decking).
~ The impact and shock absorption properties of the
flashing, together with noise resistance and minimisation
(especially where the flashing is used with metal and
other hard members, including metal decking for formwork
etc) .
~ The capacity of the flashing to prevent moisture
and dust passage into and between the joints between
members, and to cover or shroud members by providing an
overhang on either side thereof (eg. provided by
overhanging wing portions 16).
~ The capacity of the flashing to be formed into a
number of different shapes using the lines of severance
and also because it can be easily cut, torn and shaped.
Whilst the flashing has been described with reference
to a number of preferred embodiments, it should be
appreciated that the flashing can be embodied in many
other forms.
