Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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IMPRo~'EMENTS RELATING TO FL~SHING FOR BUILDINGS
This invention relates to flashing used in
buildings to provide a seal between a surface and a
member projecting therefrom. The invention is
particularly applicable to providing a seal between a
5 roof structure or wall of a buildin~ and a member or
structure passing therethrough, projecting therefrom, or
adjacent thereto.
Historically, lead or soft malleable metals in
10 sheet form have been used as a flashing material in
buildings because of the ease of deforming the material
to follow the irregular contour usually presented by the
surface of the roofing material, and in the case of lead,
because of its ability to be conveniently stretched on
15 site if required. The fashioning of the flashing on site
to suit individual situations requires considerable skill
by the wurkman in order to ensure an effective seal is
achievedl and was a relatively time consuming and
therefore costly operation.
2~ Nore recently, there has been a trend towards
using rubber or like resilient deformable mat~rials as a
substitute for lead, and to prefabricate flashing devices
from such materials in a manner to reduce the skill and
labour involved in installing same. However, such
25 materials have the disadvantage that due to their
resilience they do not readily conform to, and maintain
contact with, the surface of the roof or like to which it
is to be fitted, without the use of associated components
of non-resilient material.
It i6 therefore the object of the present
invention to provide an improved flashing product,
particularly for use in buildings, which is e~fective in
operation, convenient to install, and reduces the skill
and labour involved in installation thereof.
With this object in view, there is provided a
flashing product incorporating a section made o~ a
deformable resilient material and having attached to a
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portion of that section a member or members adapted to be
manually stretched in at least one direction and when so
stretched to be capable of maintaining said portion of
resilient material correspondingly stretched.
Conveniently, the adaption of the member to be
stretched in one direction is such tha-t compressing of the
member may also be effected. In particular the adaption of
the member may be such that it may be stretched along one
edge and compressed along the opposite edge. This enables a
portion of the member to be manually deEormed in the plane
thereof into an arcuate or curved form. The member or
members are also manually deformable in the direction normal
to the plane thereof so that it may be contoured along its
length. This contouring of the member may be effected
independently or in combination with stretching or
compressing of the member.
Conveniently, the member is provided with a
plurality of interruption along at least one edge extending
substantially in said direction of desired stretch, whereby
the member is stretched by increasing the width of the
interruption at least along part of the length of the
member. Preferably, interruptions are provided along each
of two opposite edges of the member with alternate
interruption extending from opposite edges of the member.
The interruptions preferably e~tend from the opposite edges
more than half the width of the member, or at least overlap
one another in the direction of the width of the member.
Preferably, the interruptions extend across the major part
oE the width of the member, up to about 75% to 90~ of the
width of the member.
Conveniently, the interruption may be of a shape
being wider at the edge of the member from which they
extend, such as of a V shape.
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The non-xesilient member may be of a soft
metal that is manually deformable such as aluminium, zinc
plate, or steel, the steel being preferably galvanised or
coated to resi~t corrosion. The member is preferably of
5 a strip form with a thickness of the order of 1/2 to 2
mm, conveniently about 1 mm, to provide the degree of
rigidity necessary to hold the resilient material in the
stretched or compressed condition.
The non-resilient member may be attached to
10 the de~ormable resilient material by bonding to one face
of the resilient material, either in a superimposed or
inlaid relation having one face of the member exposed.
Alternatively, the member may be embedded in the
resilient material. When the member is embedded in the
resilient material it is preferably that at least one
face of the member be bonded to the resilient material.
The member or non members may be strips of
metal with slots, notches, or slits extending in from one
or both longitudinal edges of the ~trip. The degree of
~tretch that the member may achieve without failure i~
increased with the length and member of the slots,
notches, or ~lits in the member.
When it i8 required to increase the length of
the ~trip or ~heet in the area that the member or members
are attached the application of a tension ~orce in the
direction of the length of the member will cause the
slots or slits to open to increase the width of the slots
or slit6, with a resultant stretch of the resilient
material spanning the slot or slit. Because of the
30 generally non-resilient nature o~ the material o~ the
member or member~ they will retain the stretched state
when the tension ~orce i~ released.
It many flashing products, the non-resilient
member or members are attached to a marginal edge portion
of the product so that the edge portion may be shaped
and/or contoured to closely follow the surface to which
the flashing product is being ~itted. In such products
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the marginal edge portion is req~ired to establish a
sealed relation with the surface to which it is being
fitted, and so after suitable ~hapin~ of the marginal
edge portion, suitable fastenings, such as bolts, screws
or ri~ets, are used to secure same together with the
resilient material compressed between the non-resilient
member and the surface to which the flashing product is
fitted.
With slots or slits extending in from opposite
edyes of the member or members if the slits or slots are
ge~erally equally stretched the edge of the strip will
remain generally skraight in the plane of the ~trip.
However, the edge of the strip may be curved by
str~tching one edge of the member more than the other, or
by stretching one edge and compressing the other.
In one preferred embodiment the non-resilient
members are in the form o~ a zig-zag or wave shaped
strip. Conveniently, the strips are arranged ~n a nested
relation without actual contact between adjacent strips
when attached to the resilient material. The greater the
spacing o~ the members the greater the maximum dagree of
stretch, but the degree of retention of defsrmation may
be somewhat reduced.
The use of the zig-zag or wave form in a
plurality of member~ attached to a single sheet or strip
of resilient material permits stretching in multi
directions and deformation in multi orientations.
In one form the flashing product ie a ~lashing
~trip comprising an elongated strip of rubber or like
resilient material having along the opposite longitudinal
edge portions a metallic 6trip. Each metallic skrip has
slits or slot~ extending transversely thereo~ with
alternate slit~ or ~lots extending from opposite edges o~
the metalli¢ ~trip. The metallic strips are preferably
between about 25 to 35 mm wide and 0.75 to 1.5 mm thick
and are embedded in the rubber.
This flashing strip may be used to flash the
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junction between a generally flat s~rface and a non-planar
surface, such as the junction of a roof with an upright surface
of a wall or structure. The slotted or slit metal strip
ena~les the edge portion in which it is embedded to be
5 longitudinally stretched and/or deformed to closely follow the
contour of the roof without undue tucks or folds in the
flashing strip.
The invention will be more readily understood from
the following description of several practical arrangemen~ of
10 products incorporating the presènt invention as illu trated in
the accompanying drawings.
In the drawings:
Figure 1 is a perspective view of portion of a
flashing strip.
~igure 2 is a view of a portion of the type of metal
strip used in the flashing strip ~hown in Figure 1.
Figure 3 is an enlarged view of a portion o~ the
flashing strip shown in Figure 1 formed into a curved shape.
~ igure 4 is a perspectiYe view of a known type of
20 sealing device modified to incorporate the present invention.
FigurP 5 is a perspective view of another known type
of sealing device modified to incorporate the present
invention.
Figure 6 is a perspective view of a skylight
25 installation incorporating the flashing strip.
Figure 7 is a view of a further modification of the
present invention.
Referring now to Figure 1 there is illustrated
a flashing strip for use in providing a seal between two
3~ inter~ecting surfaces such as a roof and wall or
structure projecting therefrom. The flashing strip 10 is
comprised of an elongated sheet or strip 20 o~ rubber or
like resilient material having suitable physical
properties for outdoor use, particularly extended
35 exposure to sunlight. Each longitudinal marginal edge
portion 22 of the 6heet 20 has a metal strip 21 bonded to
the 6urface thereof on the same side of the ~heet. Each
metal strip 21 has a ~eries of slits or 610ts 23, 2~
therein extending inwardly from the respective edge6 25,
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26 of the strip. The con~truction of the strip 21 is
more clearly shown in Figure 2 wherein the same reference
numeral as used in Figure 1 apply.
The strip 21 is manufactured as a continuous
5 band with the slots 23 and 24, extending from the
opposite edges 25 and 26, alternating. At the junction
of the 610ts with the edges of the strip the corners are
radiused at 30 to reduce the risk that the corners may
pierce the rubber sheet, and ~o create a leak or even ~'
10 promote tearing of the rubber sheet. Also the base of
the ~lots 23 and 24 are radiused at 31 to produce the
risk o~ the metal of the strip tearing when the strip is
stretched.
In a typical arrangement of th~ flashing strip
15 10 the strips 21 are made o~ an aluminium alloy o~ a
thickness of 1 mm and a width of 25 mm. The slots 23, 25
are of a width of 1.5 mm and a length of 18 mm. The
rubber of which the sheet 20 i8 preferably an EPDM rubber
with a hardness preferable less than 40 Durometer.
The flashing 6trip 10 as shown in Figure 1 has
the strips 21 bonded to the surface of the rubber sheet
20, and this is achieved by applying a coating of bond
primer to at ~east the surface of the strip that will
contact the sheet 20, and then bring the primed surface
25 of the strips into contact with the 6heet 20 in the
uncured 6tate. Preferably the sheet and ~trips are
pressed together such as by passing through rollers to
inlay the strips into the sheet with the rubber filling
the 810t8 23, 24 in the strips. The resulting assembly
30 is then cured.
It is to be understood that a flashing strip
as shown in Figure 1 may al~o be made with the metal
strips 23 and 24 completely embedded in the marginal edge
portions of the rubber ~heet 20. This construction i5
35 particularly desirable for aesthetic reasons. In many
applications of the flashing strip 10 the degree of
stretching of the metal strip may vary from one location
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to another, and the resultant irregular appearance of the
metal strips as would be exhibited by the construction
shown in Figure 1 may be considered objectionable. ~his
irregularity is concealed if the strips 23 and 24 are
completely embedded in the rubber sheet.
The construction o~ the flashing strip 10 with
embedded metal strips 21 may be effected by laying up the
primer coated metal strips 21 between layers of uncured
rubber and holding them in assembly under pressure and
10 heating to effect curing. An alternative method is to
extrude the rubber ~heet 20 with the metal fitrips 23 and
24 embeddeA in the marginal edge portions of the extruded
sheet and then cure the resulting assembly. The extruded
assembly can be rolled and cured in an autoclave, and so
renders this method of construction advantageous for high
volume production.
As previously described the flashing strip 10
has a slotted metal strip 21 in each ~arginal edge
portion, however in some applications a slotted metal
strip may be located in only one marginal edge portion,
the opposite edge portion may be wholly of rubber or may
hav2 a solid un-slotted metal trip therein. The
un-slotted strip may be bonded to the surface of or
embedded in the rubber sheet in the manner as previously
described in relation to the slotted strips.
When the flashing strip 10 as described above
with reference to Figures 1 and 2 is in use it i~
frequently necessary for part of one of the marginal edge
portions to increased in length such as when the flashing
strip is reguired to extend around a corner of a
struature projecting from a roof, such as a skylight
structure. This use o~ the flashing strip is illustrated
in Figure 6 o~ the accompanying drawing. The sXylight
structure 35 ~part only shown) projects from the sheet
metal roof 36 having a series of sti~fening ridges 37
extending up the slope of the roof. It is to be
understood that only part of the skylight ~tructure is
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shown in ~igure 6 representing one corner o~ that
structure.
~ he marginal edge portion 38 of the flashing
strip 40 has a continuous unslotted metal strip 41 bonded
5 thereto, as edge portion 38 is not required to be
stretched or compressed in order to be fitted around the
perimeter of the skylight structure. The marginal edge
portion 38 is secured to the skylight structure 35 at
regular intervals by screw~ 42 so that the rubber is
compressed between the strip 41 and to skylight structure
35 to provide a weather tight seal.
The rubber sheet portion 43 of the flashing
strip curve outwardly and downwardly from the marginal
edge p~rtion 38 to the opposite marginal edge portion 45
15 which lies on the surface of the roof sheet 36. The
metal strip 44 of the edge portion 45 is provided with a
series of slots 46 along its inner edge 47 and series of
610ts 48 along its outer edge 49. The slots 46 and 48
- are of the form and are arranged as previously descr~bed
20 in respect to the 610ts 23 and 24 as shown in Figures 1
and 2. In those areas of the edge portion 45 that are
straight and li~ flat on the roof sheet, as indicated at
50, the slots 46 and 48 are not ~tretched or compressed
and so the slots are of uniform width throughout their
25 length, that is as formed.
In the corner area 51 the marginal portion 45
must be increased in length to accommodate the arcuate
path it must follow around the corner of the skylight
~tructure while remaining flat on the sur~ace o~ the roof
30 sheet. This increase in length i5 obtained by stretching
the metal strip 44 by opening the slots 46 and 48 with
the outer 610ts 48 being opened wider than the inner
slots 46 to establish the curved shape. Because of the
relative ~trength o~ the metal strip 44 and the rubber
35 sheet 43, o~ce the metal ~trip q4 and the portion of the
rubber sheet, attached thereto have been stretched the
strip 44 will retain its etretched state and also will
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hold the attached portion of the ru~ber sheet in the
stretched state.
In order for the marginal portion 45 to pass
over the ridge 37 in the area 52 there must also be an
increase in the length of the marginal portion 45 by a
stretching of the metal strip 44. As the strip is not
required to follow a curved path in this area, the inner
and outer slots 46 and 4~ are each opened by generally
the same amount.
The above stretching and bending of the
slotted metal strip 46 enables the marginal portion 45 to
be shaped to be passed around corners and over ridges or
through valleys, and maintain close ~ace to face contact
with the roof sheet 36. Accordingly, when appropriately
spaced ~crews 54 are applied to fasten the marginal edge
portion 45 to the roof sheet the rubber is compressed
between the strip 44 and the roof sheet 36 to provide a
weather tight seal therebetween.
The ability to increase the length of the
marginal edge portion of the flashing strip in ~elected
location, and to selected degrees, enablies the flashing
strip to be fitted to non planar and irregular surface
and in doing so establish an e~fective ~ealing relation
therewith. In addition the ~tretching and bending of the
flashing strip is achieved without development of major
folds, pleats or tuck~ in the rubber ~heet that may
provide an area for collection of water, and present an
untidy appearance.
Figure 4 in the drawing illustrates a sealing
device specifically designed to prov$de a seal between a
pipe or duct projecting through a roo~ made of ridged
sheet material. The seal device comprises a ~lange 9 of
resilient readily de~ormable material, such as natural or
synthetic rubber, having an integral sleeve 11 extending
from the upper face of the flange. The sleeve 11 has a
tapered portion 18 tapering toward the upper free end 12,
and at the lower end has a generally cylindrical portion
12~3~8~30
13 that connects the tapered portion 18 to the flange 9.
The flange 9 has a aperture therein, (not shown) that is
co-axial with and communicates with the bore of the sleeve
11. In use the pipe or duct will pass through the aperture
and sleeve.
The wall of the cylindrical portion 13 is
preferably somewhat thicker than the adjacent portion of the
flange 9 and taperad portion 18 to provide greater
resistance to distortion in use.
The junction areas b0tween the cylindrical portion
13 and the flange 9 and tapered portion 19 are sufficiently
flexible to accommodate misalignment of the cylindrical
portion relative to the other parts of the seal device, as
may be necessary in normal use. Spaced along the tapered
portion 19 are a plurality of external ridges 14 denoting
where the sleeve may be cut off to suit elongate members of
different diameters. The ridges also provide a reinforce-
ment about the edge of the open end of the sleeve so formed.
The general construction of the sleeve 11 with
another orm of flange has been proposed in U.S. Patent No.
4,664,390,issued to D.G.Houseman on May 12,1987 and which was
developed within the same corporation as the present invention.
The opposite marginal edge portions 15 and 16 of
the flange 9 have bonded thereto the metal strips 17 that
extend the length of the flange. The metal strips 17 are
each of the construction of the strips 21 as previously
described with reference to Figures 1 and 2 of the drawing
and may be stretched, compressed, or contoured in the same
manner.
The metal strips 17 are bonded to the upper surface
of the flange 9 in the embodiment as shown, however if
desired may be embedded within the flange as previously
referred to in respect of other embodiments.
In use the seal device as shown in Figure 4 is
fitted to a pipe or duct extending through a roof sheet by
cutting the sleeve 11 off at the ridge 14 appropriate
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to the size of the pipe or duct, and inserting the pipe or
duct through the flange 9 and sleeve 11 so the flange will
lie on the upper surface of the roof sheet. As is known,
roof sheets have spaced longitudinal ribs or ridges to
impart the required strength thereto, and the flange 9 of
the sealing device must be attached in a sealed relation
thereto. The metal strips 17, which extend across these
ribs when the seal device is assemb]ed to the pipe or duct,
may be stretched and contoured so that the edge portions 15
and 16 of the flange 9 may closely follow the contour of the
roof without resulting in substantial folds and disturbances
in the area of the flange between the edge portions 15 and
16 and the sleeve 11. Screws, rivets or like fastenings are
applied to attach the edge portions to the roof sheet so the
rubber of the flange 9 is compressed between the respective
strips 17 and the roof sheet to establish the weather tight
seal therebetween.
No metal strip is attached to the edge portions 7
and 8 of the flange 9 so as to contribute to the freedom of
movement of the flange material to avoid the formation of
folds during installation. However, separate metal strips
not shown are preferably fitted using suitable fastenings to
compress the edge portions 7 and 8 adjacent the roof sheet
after fixing of the metal strips 17 to the roof sheet has
been completed.
An alternative form of seal device is shown in
Figure 5, which is similar to that described above with
reference to Figure 4, but has a relatively narrow annular
flange 55 and is an adaption of the present invention to the
seal device the subject of U.S. Patent No. 4,333,660. The
sleeve 56 is of the same general form as described with
reference to Figure 4 and will not be further described.
Between the lower end of the sleeve 56 and the flange 55 is
a re-entrant skirt 57 which provides a substantial degree of
flexibility between the sleeve and the flange to accommodate
misalignment encountered when fitting the seal device to a
~xa~s~
pipe projecting through a roof. This flexibility reduces
the degree of distortion of the sleeve and flange that may
otherwise be necessary to accommodate such misalignment.
The annular flange 55 has a lower portion S9 of
S rubber formed integral with the skirt 57 and an upper metal
strip 58 bonded to the upper face of the lower portion 59.
In an alternative construction the metal strip 58 may be
embedded in the rubber of the lower portion. The metal
strip 58 is of an annular shape complementary to the lower
portion 59 and has slots 60 extending in from each of the
inner and outer edges of the strip. The form and
arrangement of the slots 60 are the same as previously
described in respect of the metal strips illustrated in
Figures 1 and 2, and provide the same capacity to be
stretched or compressed to impart a desired shape or contour
to the flange 55 when being installed to a non-planar roof
or other surface. The flange is secured in position by
suitably located fastenings such as screws, bolts or rivets
that pass through the flange 55.
The metal strip 58 as incorporated in the seal
device shown in Figure 5 may be stamped from a flat sheet of
metal with the slots 60 being formed in the same operation
as the profile of the straight form and then further worked
into the annular shape. The rubber flange 55 may have the
metal strip 58 bonded thereto as a separate operation after
final forming of the flange, or the metal strip 58, in an
annular form may be located in a die and the flange 55 and
sleeve 56 then moulded in that die to thereby bond the metal
strip to the flange.
The metal strip 21 as previously described may be
produced in a stamping operation, or by suitable rolls that
will form the series of slots of the shape and formation
previously described. Alternatively, a wire or rod of the
suitable metal may be formed into a sinuate shape and then
the wire or rod is pressed flat as by passing through
rollers to ~orm a strip as described with reference to
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Figure 2. The pitch and amplitude of the sinuate shape is
selected, having regard to the wire or rod diameter, to give
the required slot form and spacing after being flattened.
In some constructions the sinuate wire or rod may be used in
an un-flattened state.
It will be appreciated that the m0tal strip may be
formed by other known metal working techniques and the
invention is not limited to the specific techniques
discussed herein. Also the form of the strip and the
interruption therein may take forms, other than those
specifically referred to herein, that will impart the non-
resilient deformability to the strip to permit the manual
stretching and compressing thereof.
Figure 7 of the drawings show a rubber strip 65
having two strips 66 of non-resilient material bonded to one
face thereof. The strips 66 are each of a sinuate form and
are arranged in a nesting relationship, but spaced so that
the strips are not in contact with each other, thus forming
a sinuate band 67 of rubber between the two metal strips 66.
In this construction, in addition to each strip 66 being
stretchable in the direction of the length of the strip, by
appropriate variation in the deformation of each strip 66 a
degree of shaping of the rubber strip 65 in the transverse
direction can be obtained. It is also to be understood that
the number of metal strips arranged in the nested relation
may be increased so as to form a sheet rather than a strip
of rubber, that may be manually deformed and will retain
that deformed condition.
