Apparatus and method for providing a throughgoing duct in a raised seam joint metal roof

An arrangement for sealing an opening in a roof deck by mounting a baffle plate in the roof deck so as to provide a throughgoing ducting channel, the roof deck having at least one raised seam joint intersecting the opening, the baffle plate being dimensioned such that it extends beyond the periphery of the opening in substantially all directions thereby defining a zone of overlap which extends around substantially the entire periphery of the opening, the arrangement including a capping member for capping and sealing the area where the baffle plate, the raised seam joint and the opening converge, a backing and stiffening member for being positioned on the opposite surface of the roof deck from the baffle plate and at least partially within the zone of overlap, and a fastening device for extending through and securing together the capping member, the baffle plate, the roof deck and the backing and stiffening member within the zone of overlap.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring first to FIG. 1, a roof deck generally includes a plurality of 
substantially parallel roof panels 11, 12, 13 and 14 which are joined 
edgewise by raised seam joints 20, 21 and 22. An opening 25 has been 
formed in the roof deck which intersects at least one of the raised seam 
joints, i.e., joint 21, and a fitting 26 is to be mounted over opening 25 
so as to seal opening 25 and provide a throughgoing ducting channel, such 
as for a chimney, through the roof deck. The fitting 26 generally 
includes, in the illustrated embodiment, a flat portion such as a baffle 
plate 28 and a vertically surrounding portion 29 extending therefrom. 
As shown most clearly in FIG. 1, baffle plate 28 extends beyond the 
periphery of opening 25 so as to create a zone of overlap between baffle 
plate 28 and the roof deck, as shown most clearly by the dotted lines in 
FIG. 1. 
Also shown in FIG. 1 are reduced ("cutout") portions 41 and 42 provided in 
baffle plate 28 to accommodate and partially surround the area of 
intersection of raised seam joint 21 and opening 25. 
The arrangement for sealing the opening 25 in the roof deck also generally 
includes, for each intersection of a raised seam joint such as 21 with 
opening 25, a cap member 31 having a peaked central portion which is 
generally dimensioned and contoured to fit over and lie substantially 
flush against the exposed upper surface of the raised seam joint 21 in the 
area where it intersects with opening 25 as will be described with 
reference to FIG. 1. Cap member 31 is provided with a substantially flat 
horseshoe shaped flange portion 32 having throughgoing holes for accepting 
sheet metal screws or the like. One end of cap member 31 is open, and the 
opposing end, in the embodiment of FIGS. 1 and 2, is provided with a 
rounded nose portion. 
Referring now to FIG. 2, showing the baffle plate 28 installed, a plurality 
of clamping force distributing strips 43 are secured about the periphery 
of baffle plate 28 in the zone of overlap described above by fastening 
means, for example, a multiplicity of self tapping sheet metal screws 
extending through distribution strips 43, baffle plate 28, panels 12 and 
13 and additionally backing and stiffening means disposed on the lower 
surface of the roof deck and described more fully hereinafter. 
Referring now to FIG. 3, which schematically shows a raised seam of a metal 
roof deck of a type contemplated for use in conjunction with the present 
invention, panels 12 and 13 include upraised and contoured edge portions 
15 and 16, respectively. Raised edge profiles 15 and 16 have parallell 
parts 15a and 16a respectively which end in formed edge configurations 17 
and 18, respectively, substantially as shown. It will be appreciated that 
with the formed edge configurations 17 and 18 substantially as shown, roof 
panels 12 and 13 may be snappingly interlocked with one another. Thus, the 
edge configurations 17 and 18 form a snaplock arrangement. Preferably, the 
female edges 15a 17 of roof panels 12 and 13 will be provided with a 
sealant 19 preferably a factory installed foamed, resilient and adhesive 
rubber-like strip led configuration. In the conventional way shown in the 
abovementioned patents, the roof is secured to the underlying structure by 
means of non-illustrated clips that extend into the seam and are bent over 
the male edge profile 18. Adjacent the opening 25, a portion of the edge 
configurations 17 and 18 is cut away so that the seam will be fully 
symmetrical as can be seen in FIG. 5. The cap member 31 is adapted to this 
symmetrical portion of the seam as can also be seen in FIG. 5. The 
cut-away edge portion can for example be 1-3 inches long. 
Referring now to FIG. 4, a backing and stiffening member 35, which, during 
installation, is located on the lower surface of the roof deck and 
positioned adjacent the intersection of raised seam joint 21 and opening 
25, is preferably made from a substantially flat metal plate, at one edge 
of which two cuts have been made in the form of a "T" so as to form two 
tab portions 36 and 37. As shown in FIG. 5, tab portions 36 and 37 have 
been deformed to project beyond the generally flat surface of backing and 
stiffening member 35, and have a plurality of angularly related surfaces 
which correspond to the interior surfaces of the raised seam joints, e.g., 
20, 21 and 22, of the roof deck. Backing and stiffening member 35 serves a 
number of important functions: it serves to stiffen the flat planar 
portions of roof panels 12 and 13 where their structural integrity has 
been disrupted by the provision of opening 25; it serves as a backing 
member on the under surface of the roof deck into which fastening means, 
such as self tapping sheet metal screws, may be inserted; and, through the 
incorporation of upstanding tab portions 36 and 37, it structurally 
reinforces raised seam joint 21 where it has been weakened by the 
provision of opening 25. 
It will be appreciated that a raised seam joint such as 21, if it is 
substantially continuous, has a relatively high degree of structural 
rigidity. However, its structural rigidity is substantially weakened at an 
end point such as is caused by opening 25. Backing and stiffening member 
35 serves to reinforce this relatively weakened portion of raised seam 
joint 21 and stiffen it against possible damage. 
FIG. 5 is a cross-sectional view, along the section V--V indicated in FIG. 
2, through cap member 31 and baffle plate 28 installed on the roof deck. 
Backing and stiffening member 35 is shown extending across the raised seam 
joint 21 made up of raised edge portions 15 and 16 of roof panels 12 and 
13, respectively. Upstanding tab portions 36 and 37 project into raised 
seam joint 21 and substantially conform to the interior angles and 
surfaces thereof. 
A sealing agent, preferably a strongly adhesive, flowable butyl rubber 
strip 45 (possibly factory installed) within the interior of cap member 31 
provides weatherproofing both between the cap and the upstanding seam 
referred to as 21 in FIGS. 1 and 2 and as 15, 16 in FIG. 5 and between the 
horse shoe shaped flange portion 32 of the cap 31 and the baffle plate 28. 
Flange portions 32 of cap members 31 are secured to roof panels 12 and 13 
by the provision of self tapping sheet metal screws 44 which pass through 
cap member 31, butyl rubber strip 45, baffle plate 28, roof panels 12 and 
13 and backing and stiffening member 35. Pressure distribution strips 43 
are also shown, as well as additional backing and stiffening members 33 
and 34 which may be disposed about opening 25 in the zone of overlap. As 
shown in FIG. 2, fastening means, for example, self tapping sheet metal 
screws, pass through distribution strips 43, baffle plate 28, roof panels 
12 and 13 and backing strips 33 and 34. The self tapping screws take firm 
grip in the backing members, 33, 34 35. The backing members 33, 34, 35 
should be thick enough to provide firm grips for the screws, but 
preferably not so thick that they prevent the use of self tapping screws. 
A sealing agent, preferably butyl rubber strips 60 are interposed between 
baffle plate 28 and roof panels 12 and 13 in the above described zone of 
overlap. 
It should be noted that backing and stiffening member 35 serves to minimize 
distortion of raised seam joint 21 when cap member 31 and butyl rubber 
strip 45 are secured and fastened thereover. 
The step of a preferred mode of mounting the fitting 26 to the roof panels 
12, 13 will now be described by way of example. 
a The hole 25 is cut. 
b About two inches of the snaplock forming seam edges 17, 18 are cut away. 
c The backing elements 35 are put into place as well as the backing 
elements 33, 34 so that the roof panels are backed substantially around 
the entire hole 25. 
d The cuts 41 in the baffle plate 28 of the fitting 25 are made. 
e The sealing strips 60 are placed onto the underside of the baffle plate 
28 and the baffle plate is put in place. 
f The caps with their sealants 45 are so positioned that they abut the ends 
of the seam edges 17, 18. 
g The pressure distributing strips 43 are put in place and self tapping 
screws are secured into the holes in the pressure distributing strips 43 
and in the caps 31 to take firm grips in the backing elements 33, 34, 35. 
In FIG. 5 self tapping but not self boring screws are shown. Thus, holes 
must be drilled for the screws, alternatively, self boring screws can be 
used. 
h Finally, the joint between the cap 31 and the seam edges 17, 18 should be 
visually checked and, if necessary, additional butyl rubber should be put 
into the joint to secure tightness. It is appreciated that this joint can 
be visibly checked. 
In FIG. 6, there is shown an alternative embodiment of the invention, 
wherein distributing strips 43 are configured so as to have a generally 
right angled cross-section, and wherein cap member 31 is made of an 
aluminum profile provided with a squared-off closed end 46, as opposed to 
the rounded nose portion shown in the embodiment of FIGS. 1 and 2 which 
shows a cap of formed steel plate. In a further alternative embodiment of 
the invention, the squared-off closed end 46 may be configured to be 
inclined with respect to the roof deck when installed rather than 
perpendicular thereto as shown in FIG. 6. 
Referring now to FIG. 7, in the alternative embodiment of FIG. 6, instead 
of the flat backing strips 33, 34 shown in FIG. 5, there are profiled 
(C-profile) backing members 62 which will take support against the 
underlying roof structure 65 and prevent the screws 44 from reaching the 
underlying roof structure 65. Thus, the roof panels will be lifted off the 
underlying roof structure 65 which, however, is no disadvantage. 
The pressure distribution members 43 is also profiled and form together 
with the profiled backing member 43 a structure that is more rigid than 
the one shown in FIG. 5, which can be advantageous, particularly when the 
fitting 26 is wide. 
In a particularly preferred embodiment, the width of roof panels 12 and 13 
of pre-painted steel is on the order of 610 mm, and roof panels 12 and 13 
weigh on the order of 6.0 Kg/m.sup.2 and 3.6 Kg/linear meter. 
Additionally, in this embodiment, cap member 31 and backing members 33, 
34, 35 have a thickness of from about 1.5 to about 2.5 mm, while roof 
members 12 and 13 are about 0.6 mm in thickness. 
The invention as described hereinabove in the context of the preferred 
embodiments is not to be taken as limited to all of the provided details 
thereof, since modifications and variations thereof may be made without 
departing from the spirit and scope of the invention.