Note: Descriptions are shown in the official language in which they were submitted.
CA 02568777 2006-11-23
A TRUSS AND PURLIN SUPPORT APPARATUS AND A METHOD OF MAKING AND
USING SAME WITH BUILDING SUPPORTS AND FLOOR AND ROOF SHEATHING
FIELD OF THE INVENTION
f0001] The present invention relates to the field of floor and
j=oof support apparatus and, more particularly, to a truss and purlin
:;upport apparatus and a method of making and using same with
t)uilding supports and floor and roof sheathing.
BACKGROUND OF THE INVENTION
10002] In the construction industry for buildings, including
residential, commercial and institutional and high rise, there is a
c:ontinuing need to achieve higher economic efficiencies in cost of
niaterials, of fabrication, and of installation labor for floor and
roof systems, as well as to achieve improved floor and roof
structural efficiency. Though still largely undeveloped, the
c=onstruction industry may be beginning to consider the use of light
gauge steel (hereinafter, alternately referred to as "LGS" and/or
"light weight steel"} constructions in this regard.
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(0003] In the prior art, conventional floor constructions in LGS
inay heretofore have used "C"-channel floor joists 30, such as those
assembled as illustrated in Figure 1. Such prior art LGS floor
Systerns may have included the use of such "C"-channel floor joists
,30, in a back-to-back orientation, in typical depths of $", 10",
L2", and 14", and in typical gauges ranging between 18 gauge and 14
qauge. As illustrated in Figure 1, such prior art floor joists 30,
in the aforesaid back-to-back orienLation, may heretofore have been
supported on external foundation walls 22 and on center load bearing
walls 24. Such prior art installations may often have also required
the use of rim joists 34 and "X"-bracings 36, throughout, to provide
it requisite level of stability for the floor, and/or to reduce the
likelihood that the prior art joists 30 might fall over under load
conditions (not shown). It would be desirable to provide a floor
;system that does not required the use of such rim joists 34_ In
addition, prior art stiffening members 32 may heretofore have been
required to reduce the likelihood of web crippling which may arise
tinder concentrated loads (e.g., from wall studs in situations where
multiple stories are present). Such prior art floor systems,
elspecially insofar as they may have been constructed of LGS, may
Y:ave been very time-consuming to construct and cumbersome to
install, and often may have been quite costly in terms of material
c:osts.
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[0004] In addition, prior art systems that included "C"-channel
joists 30 have been subject to the significant problem of providing
che requisite level of stability for the "C"-channel joists 30 in
their upright position (as shown in Figures 1 and 2)_ The
t3forementioned problem may heretofore have been especially acute in
situations where the "C"-channel joists 30 may have spanned over
three walls (i.e., where the floor system is supported by two
exterior foundation walls 22 and by a third center load-bearing wall
24 substantially at the mid-point of the floor). Although the prior
3rt rim joists 34 may have provided some measure of increased
atability at the extremities, the "C"-channel joists 30 may not have
been sufficiently stable at the at center load bearing wall 24. As
well, certain minimum bearing requirements for floor joists resting
on supporting structures, in this case the load bearing wall 24, may
have necessitated the overlap of the prior art "C"-channel joists 30
in the manner best seen in Figure 2. That is, it may heretofore
tiave been necessary, as shown in Figure 2, to overlap adjacent ones
of the "C"-channel joists 30 on top of the supporting structure.
The aforementioned problems of collapsing and/or over-turning under
concentrated loads is one which may have been inherent in such prior
art arrangements. As such, in the prior art, it may have been
rLecessary to install expensive "x"-bracing 36 within such prior art
floor systems, which (apart from the significant added expense) may
heretofore have been particularly difficult to accomplish for LGS
constructions_
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[0005] Use of prior art floor systems may also have presented
additional headaches insofar as an "offset seam" may have been
present (as indicated generally by arrows "Z" in Figure 2). Floor
sheathing that might heretofore have been placed on top of the
offset prior art "C"-channel joists 30 often may not have been
properly and/or readily aligned therewith. In the result,
considerable adjustments may have been necessitated during
Lnstallation of sheathing over such prior art floor systems and may
not have lended itself to a clean construction detail.
[0006] The aforementioned problem with prior art floor systems
inay have been somewhat more pronounced in low rise hotel
constructions where a multitude of units, separated merely by center
;I.oad bearing walls 24, may be present adjacent to one another. In
such situations, and/or if several floors are constructed on top of
each other, prior art "C"-channel joists 30 may have become
particularly unstable. Extreme care and "X"-bracing 36 may
heretofore have been required to achieve a requisite level of
ntability, especially when under an applied load of several building
t;tories. Moxeover, such uses of prior art systems may not have
afforded and/or guaranteed the desired level of sound stability,
especially when under an applied load of several building stories.
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[0007] It is thus an object of this invention to obviate or
mitigate at least one of the above mentioned disadvantages of the
prior art.
SUMMARY OF THE INVENTION
[0008] In accordance with the present invention, there is
disclosed a truss and purlin support apparatus for use with building
:3upport members and a substantially planar substrate sheathing
member_ The apparatus includes a plurality of Pratt-style elongate
truss members and a plurality of purlin members. Each of the truss
members has at least two support portions longitudinally spaced from
one another. The support portions are adapted to operatively engage
and transfer loads to the building support members_ Each of the
truss members incJ.udes an elongate top chord, an elongate bottom
chord, and a plurality of web members securely extending between the
top chord and the bottom chord. Each of the purlin members extends
in a substantially transverse direction relative to the elongate
truss members. Each of the purlin members has an underside portion
that is shaped to define a plurality of notched portions_ The
riotched portions are spaced from one ainother in the transverse
direction along the underside portion. Each of the notched portions
is saddled over a respective top chord of the truss members, so as
to restrict sliding movement of the purlin members in the transverse
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direction. The purlin members operatively support the substrate
sheathing member thereon. The top chord, the bottom chord, the web
members, and the purlin members are constructed from roll-formed
light gauge steel material.
[0009] According to an aspect of one preferred embodiment of the
tinvention, each of the truss members may preferably, but need not
necessarily, have a center of gravity that is operatively located
below the support portions.
f0010) According to an aspect of one preferred embodiment of the
invention, neighboring ones of the truss members may preferably, but
rieed not necessarily, be spaced by a truss on-center distance in the
substantially transverse direction that is selected from the group
consisting of about 36 inches and about 48 inches.
[0011] According to an aspect of one preferred embodiment of the
invention, neighboring ones of the purlin members may preferably,
but need not necessarily, be spaced by a purlin on-center distance
in a substantially longitudinal direction that is selected from the
group consisting of about 16 inches and about 24 inches.
[0012] According to an aspect of one preferred enibodiment of the
invention, each top chord and each bottom chord may preferably, but
need not necessarily, be shaped, in profile, so as to define a
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substantially "U"-shaped chord portion and two substantially "L"-
shaped chord portions. The "U"-shaped chord portion may preferably,
but need not necessarily, include two substantially planar chord
side portions extending substantially at right angles from opposing
crnds of a substantially planar central chord base portion. The
chord side portions may preferably, but need not necessarily, define
a web-receiving aperture therebetween. Each of the "L"-shaped chord
portions may preferabiy, but need not necessarily, include a
yubstantiaily planar first chord segment and a substantially planar
second chord segment. The first chord segment may preferably, but
need not necessarily, extend in a substantially outward direction
and substantially at right angles from a respective one of the chord
side portions. The second chord segment may preferably, but need
riot necessarily, extend substantially at right angles from the first
rhord segment. In each of the truss members, the web-receiving
aperture of the bottom chord may preferably, but need not
necessarily, face in a substantially upward direction and the web-
receiving aperture of the top chord may preferably, but need not
necessarily, face in a substantially downward direction. Each of
the web members may preferably, but need not necessarily, extend
into each web-receiving aperture, and securely engage each "U"-
shaped chord portion, of the top chord and of the bottom chord.
[0013] According to an aspect of one preferred embodiment of the
invention, one or more of the central chord base portion and the
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chord side portions of each top chord and each bottom chord may
preferably, but need not necessarily, be shaped so as to define a
stiffening projection substantially along a longitudinal extent
thereof, whereby each top chord and each bottom Ghord may
preferably, but need not necessarily, be provided with structural
rigidity.
[0014] According to an aspect of one preferred embodiment of the
invention, in each top chord and in each bottom chord, the chord
side portions may preferably, but need not necessarily, be shaped so
as to define a plurality of longitudinally spaced locator apertures
therein. Each of the web members may preferably, but need not
necessarily, be provided with end portions that are each shaped to
ciefine a locator aperture mating portion. Each of the web members
may preferably, but need not necessarily, be located within each
web-receiving aperture, and securely engage each "U"-shaped chord
portion, of 'the top chord and of the bottom chord. Each locator
aperture mating portion may preferably, but need not necessarily, be
substantially securely aligned with one of the locator apertures.
f0015] According to an aspect of one preferred embodiment Of the
invention, each of the truss members may preferably, but need not
necessarily, additionally include two support stiffening members,
each preferably, but not necessaxily, securely engaging the top
chord substantially adjacent to a respective one of the support
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portions. Each of the support stiffening members may preferably,
but need not necessarily, be positioned within the web-receiving
aperture of the top chord. The support stiffening members may
preferably, but need not. necessarily, substantially maintain local
structural integrity of the support portions preferably, but not
necessarily, whilst the support portions operatively transfer the
Loads to the building support members_
[0016] According to an aspect of one preferred embodiment of the
invention, each of, the support stiffening members may preferably,
but need not necessarily, be shaped, in profile, so as to define a
substantially 'C"-shaped support stiffening portion. The "C"-shaped
support stiffening portion may preferably, but need not necessarily,
include two substantially planar support side portions extending
substantially at right angles from opposing ends of a substantially
planar central support base portion. The central support base
portion may preferably, but need not necessarily, be positioned
substantially vertically within the web-receiving aperture of the
top chord.
10017] According to an aspect of one preferred embodiment of the
invention, each of the purlin members may preferably, but need not
necessarily, be shaped so as to define, remotely of the notched
portions, a substantially "C"-shaped purlin profile that faces in
the substantially downward direction.
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[0018] According to an aspect of one preferred embodiment of the
invention, the "C"-shaped purlin profile may preferably, but need
not necessarily, be defined by a substantially planar central purlin
base portion and two substantially "i,"-shaped purlin portions. Each
of the "L"-shaped purlin portions may preferably, but need not
necessarily, include a substantially planar first purlin segment and
a substantially planar second purlin segment. The first purlin
:-3egment may preferably, but need not necessarily, extend
substantially at right angles from one respective end of the purlin
base portion. The second purlin segment may preferably, but need
not necessarily, extend in a substantially inward direction and
substantially at right angles from the first purlin segment.
[0019] According to an aspect of one preferred embodiment of the
invention, the chord base portion of the top chord may preferably,
but need not necessarily, securely engage the purlin base portion
adjacent to one of the notched portions. The chord base portion may
preferably, but need not necessarily, be substantially flush with
the purlin base portion. The chord base portion may preferably, but
need not necessarily, operatively substantially support the
substrate sheathing member.
[0020) According to an aspect of one preferred embodiment of the
invention, the opposing ends of the central chord base portion of
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the top chord may preferably, but need not necessarily, define a
concave portion therebetween. The concave portion may preferably,
but need not necessarily, face in the upward direction. According
to this aspect of the invention, the apparatus may preferably, but
need not necessarily, be adapted to additionally include a
predetermined amount of an adhesive operatively interposed in
adhering relation substantially between the concave portion and the
substrate sheathing member.
10021] According to an aspect of one preferred ernbodiment of the
invention, each of the purlin members may preferably, but need not
riecessarily, be shaped so as to define, substantially adjacent to
the notched portions, a substantially "U"-shaped purlin profile that
faces in the substantially downward direction. The "U"-shaped
purlin profile may pxeferably, but need not necessarily, inulude two
purlin side portions extending substantially at right angles from
opposing ends of the purlin base portion. The first purlin segment
may preferably, but need not necessarily, extend beyond the purlin
side portions in the downward direction. The purlin side portions
may preferably, but need not necessarily, securely engage the chord
base portion of the top chord. The puriin side portions may
preferably, but need not necessarily, define an up-set portion that
extends between each of the notched portions and the purlin base
portion. The chord base portion of the top chord may preferably,
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but need not necessarily, be operatively verLicaZly spaced from the
:3ubstrate sheathing member.
[0022] According to an aspect of one preferred embodiment of the
invention, each of the web members may preferably, but need not
necessarily, be shaped, in profile, so as to define a sub3tantially
"C"-shaped web portion.
[0023] According to an aspect of one preferred embodiment of the
invention, the "C"-shaped web portion may preferably, but need not
necessarily, include a substantially planar central web base portion
and two substantially "L"-shaped web side portions. Each of the web
side portions may preferably, but need not necessarily, include a
substantially planar first web segment and a substantially planar
second web segment. The first web segment may preferably, but need
not necessarily, extend substantially at right angles from one
respective end of the web base portion. The second web segment may
preferably, but need not necessarily, extend in a substantially
inward direction and substantially at right angles from the first
web segment.
[0024] According to an aspect of one preferred embodiment of the
invention, each of the truss members may preferably, but need not
necessarily, additionally include two load distribution plates, each
securely engaging the top chord. Each of the load distribution
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plates may preferably, but need riot necessarily, be operatively
substantially interposed between a respective one of the support
portions and one of the building support members. The load
distribution plates may preferably, but need not necessarily,
operatively transfer the loads to the building support members
preferably, but not necessarily, whilst substantially maintaining
local structural integrity of the building support members.
[0025] According to an aspect of, one preferred embodiment of the
invention, each of the load distribution plates may preferably, but
need not necessarily, be operatively securely fastened to one of the
building support members.
1.0026] In accordance with the present invention, there is also
disclosed a method of forming a truss and purlin support apparatus
for use with building support members. The method includes a chord
forming step, a web forming step, and a purlin forming step. In the
chord forming step, a plurality of top chords and bottom chords are
roll-formed by passing first elongate sheets of light gauge steel
niaterial through a series of roll-forming chord tool sets_ Passage
of the first elongate sheets through each successive one of the
chord tool sets progressively forms the top chords and the bottom
chords. In the web forming step, a plurality of web members are
roll-formed by passing second elongate sheets of light gauge steel
material through a series of roll-forming web tool sets, Passage of
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the second elongate sheets through each successive one of the web
'tool sets progressively forms the web members. In the purlin
forming step, a plurality of purlin members are roll-formed by
passing a plurality of third elongate sheets of light gauge steel
material through a series of roll-forming purlin tool sets. Passage
of the third elongate sheets through each successive one of the
purlin tool sets progressively forms the purlin members, such that
caach of the purlin members has an underside portion that defines a
plurality of notched portions that are longitudinally spaced from
one another. Each of the web members is adapted to be operatively
secured between one of the top chords and one of the bottom chords
to form elongate truss members. The truss members are securable on
the building support members, The truss members are adapted to be
nested and secured within the notched portions of the purlin
members. The purlin members operatively extend in a transverse
direction relative to the elongate truss members. Each of the
purlin members is adapted to operatively support a substantially
planar substrate sheathing member thereon.
r0027) According to an aspect of one preferred embodiment of the
invention, the method may preferably, but need not necessarily,
additionally include a purlin sheet forming step before the purlin
forming step. In the purlin sheet forming step, the plurality of
the third elongate sheets may preferably, but need not necessarily,
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bc formed with a plurality of opposed notch pairs along longitudinal
edges thereof.
[0028] According to an aspect of one preferred embodiment of the
i.nvention, in the purlin sheet forming step, neighboring ones of the
opposed notch pairs may preferably, but need not necessarily, be
spaced by a truss on-center distance that is selected from the group
consisting af about 36 inches and about 48 inches.
[0029] According to an aspect of one preferred embodiment of the
invention, in the chord forming step, each of the top chords and the
bottom chords may preferably, but need not necessarily, be roll-
formed so that a chord profile of each of the top chords and the
bottom chords defines a substantially "U"-shaped chord portion and
t_wo substantially "L"-shaped chord portions. The "U"-shaped chord
portion may preferably, but need not necessarily, include two
substantially planar chord side portions extending substantially at
right angles frvm opposing ends of a substantially planar central
chord base portion. The chord side portions may preferably, but
need not necessarily, define a web-receiving aperture therebetween.
Each of the "L"-shaped chord portions may preferably, but need not
necessarily, inG].ude a substantially planar first chord segment and
a substantially planar second chord segment. The first chord
segment may preferably, but need not necessarily, extend in a
substantially outward direction and substantially at right angles
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from a respective one of the chord side portions_ The second chord
segment may preferably, but need not necessarily, extend
substantially at right angles from the first chord segment. The
web-receiving aperture of each of the bottom chords may preferably,
but need not necessarily, operatively face in a substantially upward
cJirection and the web-receiving aperture of each of the top chords
may preferably, but need not necessarily, operatively face in a
substantially downward direction. Each of the web members may
preferably, but need not necessarily, be operatively adapted to
extend into each web-receiving aperture, and to be secured to each
"U"-shaped chord portion, of each of the top chords and the bottom
chords.
(0030I According to an aspect of one preferred embodiment of the
i.nvention, in the chord forming step, one or more of the central
chord base portion and the chord side portions of each of the top
chords and the bottom chords may preferably, but need not
necessarily, be roll-formed so as to define a stiffening projection
substantially along a longitudinal extent thereof.
[0031] According tp an aspect of one preferred embodiment of the
invention, in the chord forming step, a plurality of longitudinally
spaced locator apertures may preferably, but need not necessarily,
be punched in the chord side portions of each of the top chords and
the bottom chords. In the web forming step, a locator aperture
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mating portion may preferably, but need not necessarily, be punched
in each end portion of each of the web members. Each locator
aperture mating portion may preferably, but need not necessarily, be
adapted to be operatively aligned with one of the locator apertures.
[0032] According to an aspect of one preferred embodiment of the
invention, the method may preferably, but need not necessarily,
zidditionally include a support stiffener forming step. In the
support stiffener forming step, a plurality of support stiffening
members may preferably, but need not necessarily, be roll-formed by
passing the second elongate sheets through the series of roll-
i:orming web tool sets. Passage of the second elongate sheets
through each successive one of the web tool sets may preferably, but
need not necessarily, progressively form the support stiffening
members, such that a support profile of each of the support
stiffening members may preferably, but need not necessarily, define
a substantially "C"-shaped support stiffening portion. The "C"-
:;haped support stiffening portion may preferably, but need not
necessarily, include two substantially planar support side portions
etxtending substantially at right angles from opposing ends of a
substantially planar central support base portion. The web-
receiving aperture of each of the top chords may preferably, but
need not necessarily, be adapted to operatively receive two support
stiffening members therewithin. Each of the support stiffening
ntembers may preferably, but need not necessarily, be substantially
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adjacent to the support portions. The central support base portion
inay preferably, but need not necessarily, be positioned
substantially vertically.
[0033] According to an aspect of one preferred embodiment of the
Lnvention, in the chord forming step, the opposing ends of the
central chord base portion of each of the top chords may preferably,
but need not necessarily, be roll-formed to define a concave portion
i--herebetween. The concave portion may preferably, but need not
necessarily, operatively face in the upward direction. The concave
portion may preferably, but need not necessarily, be adapted to
operatively receive a predetermined amount of an adhesive.
[0034] According to an aspect of one preferred embodiment of the
invention, in the purlin forming step, each of the purlin members
inay preferably, but need not necessarily, be roll-formed so as to
define, remotely of the notched portions, a substantially "C"-shaped
purlin profile that faces in the substantially downward direction.
[0035] According to an aspect of one preferred embodiment of the
invention, in the purlin forming step, the "C"-shaped purlin profile
inay preferably, but need not necessarily, be roll-formed to include
Ei substantially planar central purlin base portion and two
substantially "L"-shaped purlin portions. Each of the "L"-shaped
purlin portions may preferably, but need not necessarily, include a
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substantially planar first purlin segment and a substantially planar
second purlin segment. The first purlin segment may preferably, but
need not necessarily, extend substantially at right angles from one
respective end of the purlin base portion. The second purlin
segment may preferably, but rieed not necessarily, extend in a
substantially inward direction and substantially at right angles
from the first purlin segment.
[0036] According to an aspect of one preferred embodiment of the
invention, in the purlin forming step, each of the purlin members
rnay preferably, but need not necessarily, be roll-formed so as to
kiefine, substantially adjacent to the notched portions, a
substantially "t7"-shaped purlin profile that faces in the
substantially downward direction. The "U"-shaped purlin profile
rnay preferably, but need not necessarily, additionally include two
purlin side portions extending substantially at right angles from
opposing ends of the purlin base portion. The first purlin segment
rnay preferably, but need not necessarily, extend beyond the purlin
side portions in the downward direction. Each of the purlin side
portions may preferably, but need not necessarily, define an up-set
portion that extends between each of the notched portions and the
purlin base portion. The purlin side portions may preferably, but
sieed not necessarily, operatively engage the chord base portion of
each of the top chords. The chord base portion of the top chord may
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preferably, but need not necessarily, be operatively vertically
spaced from the substrate sheathing member.
[0037] According to an aspect of one preferred embodiment of the
invention, in the web forming step, each of the web members may
preferably, but need not necessarily, be roll-formed so that a web
profile of each of the web members defines a substantially "C"-
shaped web portion.
[0039] According to an aspect of one preferred embodiment of the
invention, in the web forming step, the "C"-shaped web portion may
preferably, but need not necessarily, be roll-formed to include a
substantially planar centra7, web base portion and two substantially
"L"-shaped web side poTtions. Each of the web side portions may
preferably, but need not necessarily, include a substantially planar
first web segment and a substantially planar second web segment.
The first web segment may preferably, but need not necessarily,
extend substantially at right angles from one respective end of the
web base portion. The second web segment may preferably, but need
not necessarily, extend in a substantially inward direction and
r:ubstantially at right angles from the first web segment.
[0039] In accordance with the present invention, there is
Eidditionally disclosed a method of forming a truss and purlin
5upport apparatus on building support members. The method includes
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a truss assembling step, a truss supporting step after the truss
assembling step, an apparatus assembling step, and a sheathing step
after the apparatus assembling step. In the truss assembling step,
a plurality of elongate truss members may preferably, but need not
necessarily, be assembled, each preferably, but not necessarily,
having a plurality of support portions longitudinally spaced from
one another, and each preferably, but not necessarily, being
assembled by locating and securing a plurality of roll-formed web
members between a roll-formed top chord and a roll-formed bottom
chord. In the truss supporting step, the support portions of the
truss members may preferably, but need not necessarily, be located
and secured on the building support members. In the apparatus
assembling step, the truss members may preferably, but need not
necessarily, be nested and secured within a plurality of notched
portions of a plurality of roll-formed purlin members. The purlin
members may preferably, but need not necessarily, extend in a
transverse direction relative to the elongate truss members, so as
to preferably, but not necessarily, restrict sliding movement of the
purlin members in the transverse direction. In the sheathing step,
a substantially planar substrate sheathing member may preferably,
but need not necessarily, be supported on the purlin members.
[00401 According to an aspect of one preferred embodiment of the
invention, in the truss supporting step, the centers of gravity of
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the truss members may preferably, but need not necessarily, be
located below the support portions.
[0041] According to an aspect of one preferred embodiment of the
invention, in the apparatus assembling step, neighboring ones of the
purlin members may preferably, but need not necessarily, be spaced
in a substantially longitudinal direction by a purlin on-center
distance that is selected from the group consisting of about 16
inches and about 24 inches.
[0042] According to an aspect of one preferred embodiment of the
i,nvention, in the truss supporting step, two load distribution
plates, securely engaging the top chord, may preferably, but need
not necessarily, be substantially securely interposed between the
support portions and the building support members.
[0043] According to an aspect of one preferred embodiment of the
invention, in the truss supportinq step, the load distribution
plates may preferably, but need not necessarily, be securely
fastened to the building support members.
[0044] According to an aspect of one preferred embodiment of the
invention, in the apparatus assembling step, each of the top chords
may preferably, but need not necessarily, be substantially flush
with each of the purlin membexs. In the sheathing step, the top
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chord may preferably, but need not r'iecessarily, substantially
:aupport the substrate sheathing membex.
[0045] According to an aspect of one preferred embodiment of the
~nvention, the method may preferably, but need not necessarily,
additionally include a gluing step, before the sheathing step, of
applying a predetexmined amount of an adhesive preferably, but not
necessarily, to one of the substrate sheathing member and a upward-
Lacing concave portion of the top chord. In the sheathing step, the
predetermined amount of the adhesive may preferably, but need not
necessarily, be operatively interposed in adhering relation
substantially between the concave portion and the substrate
sheathing member.
[0046] According to an aspect of one preferred embodiment of the
i.nvention, in the apparatus assembling step, up-set portions of the
purlin members preferably, but not necessarily, substantially
adjacent to the notched portions may preferably, but need not
necessarily, engage each the top chord. In the sheathing step, the
top chord may preferably, but need not necessarily, be vertically
spaced from the substrate sheathing member.
10047] Other advantages, features and characteristics of the
present invention, as well as methods of operation and functions of
the related elements of the structure, and the combination of parts
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and economies of manufacture, will become more apparent upon
consideration of the following detailed description and the appended
claims with reference to the accompanying drawings, the latter of
which are briefly described hereinbelow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0048] Figure 1 of the drawings appended hereto is a top
perspective view of a prior art floor system;
[0049] Figure 2 is an enlarged view of encircled area 2 of
f'igure 1;
[0050] Figure 3 of the drawings is a top perspective view of a
floor support apparatus according to the present invention;
[0051] Figure 3A is an enlarged top perSpective view of a
portion of the floor support apparatus of Figure 3;
[0052] Figure 4 of the drawings is a top perspective view of
another floor support apparatus according to the present invention;
[0053] Figure 5 is a top perspective view of a portion of one of
the truss members shown in Figure 3;
- 24 -
CA 02568777 2006-11-23
[0054] Figure 6 is an enlarged view of encircled area 6 of
Figure 5;
(0055] Figure 7 is a top perspective view of a portion of one of
the top chords shown in Figure 5;
[0056] Figure 8 is a top perspective view of one of the web
members shown in Figure 5;
1:0057) Figure eA is a top perspective view of a support
stiffening member shown in Figure 5;
[0058] Figure 9 is a top front perspective view of one of the
floor purlin members shown in Figure 3;
(0059] Figure 10 is a top front perspective view of a roof
purlin member of a roof support apparatus according to the
invention;
[0060] Fiqure 11 is a top perspective view of a low rise hotel
installation of the floor support apparatus of Figure 3;
CA 02568777 2006-11-23
[0061] Figure 12 is a top perspective view of a roof support
apparatus according to the invention;
[0062] Figure 13 is a top perspective view of portions of a top
chord and a roof purlin member shown in Figure 12;
[0063] F'iQure 14 of the drawings is a front view of the top
chord of Figure 7;
[0064] Figure 15 of the drawings is a front sectional view of
the floor sheathing and one of the top chords shown in Figure 3;
f0065] Figure 16 is a top rear perspective view of the roof
purlin member of Figure 10;
[0066) Figure 17 is a top rear perspective view of the floor
purlin member of Figure 9;
[0067] Figure 18 of the drawings is a top view of a portion of a
light gauge steel sheet used in roll-forming the floor purlin
member of Figure 9; and
[0068] Figure 19 is a side view of a corresponding portion of a
floor purlin member roll-formed from the sheet shown in Figure 18;
26
CA 02568777 2006-11-23
DETAILED DESCRIPTION OF A PREFERREfl EMBODIML7T
[0069] A truss and purlin support apparatus 40 according to the
invention in shown in Figure 3 of the drawings in use with building
support members 20 and substantially planar substrate sheathing
members 26. The apparatus 40 includes a plurality of Pratt-style
elongate truss members 50 and a plurality of purlin members 120.
[0070] Each of the truss members 50 has at least two support
portions 52 longitudinally spaced from one another. The support
portions 52 are adapted to operatively engage and transfer loads to
the building support melnbers 20.
[0071) Each of the truss members 50 includes an elongate top
chord 54b, an elongate bottom chord 54a, and a plurality of web
members 80 securely exteriding between the top chord 54b and the
bottom chord 54a. The top chord 54b, the bottom chord 54a, the web
members 80, and the purlin members 120 are preferably constructed
from roll-formed light gauge steel material. Each top chord 54b
and each bottom chord 54a may preferably, but need not necessarily,
be shaped, in profile, so as to define a substantially "U"-shaped
chord portion 56 and two substantially "L"-shaped chord portions
72.
27
CA 02568777 2006-11-23
[0072] The "U"-shaped chord portion 56 may preferably, but need
not necessarily, include two substantially planar chord side
portions 64 extending substantially at right angles from opposing
ends 60 of a substantially planar central chord base portion 58.
The chord side portions 64 may preferably, but need not
necessarily, define a web-receiving aperture 66 therebetween.
f0073] One or more of the central chord base portion 58 and the
chord side portions 64 of each top chord 54b and each bottom chord
54a may preferably, but need not necessarily, be shaped so as to
define a stiffening projection 68 substantially along a
longitudinal extent thereof, whereby each top chord 54b and each
bottom chord 54a may preferably, but need not necessarily, be
provided with structural rigidity.
[0074] In each top chord 54b and in each bottom chord 54a, the
chord side portions 64 may preferably, but need not necessarily, be
shaped so as to define a plurality of longitudinally spaced locator
apertures 70 therein.
j0075] Each of the "L"-shaped chord portions 72 may preferably,
but need not necessarily, include a substantially planar first
chord segment 74 and a substantially planar second chord segment
76. The first chord segment 74 may preferably, but need not
28
CA 02568777 2006-11-23
necessarily, extend in a subs'L-antially outward direction "D" and
:;ubstantialJ.y at right angles from a respective one of the chord
szde portions 64. The second chord segment 76 may preferably, but
need not necessarily, extend substantially at right angles from the
first chord segment 74,
1:0076] In each of the truss members 50, the web-receiving
aperture 66 of the bottom chord 54a may preferably, but need not
iiecessarily, face in a substantially upward direction "F" and the
web-receiving aperture 66 of the top chord 54b may preferably, but
need not necessarily, face in a substantially downward direction
"G". Each of the web members 80 may preferably, but need not
necessarily, extend into and be located within each web-receiving
aperture 66, and securely engage each "U"-shaped chord portion 56,
of the top chord 54b and of the bottom chord 54a.
[0077] As best seen in Figure 8, each of the web members 80 may
preferably, but need not necessarily, be provided with end portions
that are each shaped to define a locator aperture mating portion
84. Each locator aperture mating portion 84 may preferably, but
need not necessarily, be substantially securely aligned with one of
the locator apertures 70 by web fasteners (not shown).
[0078] Each of the web members 80 may preferably, but need not
necessarily, be shaped, in profile, so as to define a substantially
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CA 02568777 2006-11-23
"C"-shaped web portion 86. The "C"-shaped web portion 86 may
preferably, but need not necessarily, include a substantially
planar centxal web base portion 88 and two substantially "L"-shaped
web side portions 90. Each of the web side portions 90 may
preferably, but need not necessarily, include a substantially
planar first web segment 92 and a substantially planar second web
r:egment 94. The first web segment 92 may preferably, but need not
necessarily, extend substantially at right angles from one
r-espective end of the web base portion 88. The second web segment
94 may preferably, but need not necessarily, extend in a
substantially inward direction "E" and substantially at right
angles from the first web segment 92.
[0079] Each of the truss members 50 may preferably, but need not
necessarily, have a center of gravity (not shown) that is
operatively located below the support portions 52.
[0080] Each of the truss members 50 may preferably, but need not
raecessarily, additionally include two support stiffening members
100, each preferably, but not necessarily, securely engaging the
top chord 54b substantially adjacent to a respective one of the
support portions 52. Each of the support stiffening members 100
may preferably, but need not necessarily, be positioned within the
web-receiving aperture 66 of the top chord 54b. The support
stiffening members 100 may preferably, but need not necessarily,
CA 02568777 2006-11-23
,qubstantially maintain local structural integrity of the support
portions 52 preferably, but not necessarily, whilst the support
portions 52 operatively transfer the loads to the building support
i-nembers 20.
!0081) Each of the support stiffening members 100 (as best seen
in Figure 8A) may preferably, but need not necessarily, be shaped,
:in profile, so as to define a substantially "C"-shaped support
:;tiffening portion 102. The "C"-shaped support stiffening portion
102 may preferably, but need not necessarily, include two
substantially planar support side portions 108 extending
-~ubstantially at right angles from opposing ends 106 of a
substantially planar central support base portion 104. The central
support base portion 104 may preferably, but need not necessarily,
be positioned substantially vertically within the web-receiving
aperture 66 of the top chord 54b (as best seen in Figure 6).
[00821 Each of the truss members 50 may preferably, but need not
necessarily, additionally include two load distribution plates 110,
each securely engaging the top chord 54b. Each of the load
distribution plates 110 may preferably, but need not necessarily,
be operatively substantially interposed between a respective one of
the support portions 52 and one of the building support members 20.
'i'he load distribution plates 110 may preferably, but need not
necessarily, operatively transfer the loads to the building support
31
CA 02568777 2006-11-23
mcmbers 20 preferably, but not necessarily, whilst substantially
rnaintaining local structural integrity of the building support
members 20. Each of the load distribution plates 110 may
preferably, but need not necessarily, be operatively securely
fastened, through fastening apertures 112, to one of the building
support members 20.
~0083] Each of the purlin members 120 extends in a substantially
1.ransverse direction "B" relative to the elongate truss members 50.
Each of the purlin members 120 has an underside portion 124 that
is shaped to define a plurality of notched portions 126. The
riotched portions 126 may extend to end portions 122 0f the purlin
ntembers 120
10084] The notched portions 126 are spaced from one another in
the transverse direction "B" along the undersxde portion 124. Each
of the notched portions 126 is saddled over a respective top chord
54b of the truss members 50, so as to restrict sliding movement of
the purlin members 120 in the transverse direction "B".
t00851 Each of the purlin members 120 may preferably, but need
not necessarily, be shaped so as to define, remotely of the notched
portions 126, a substantially "C"-shaped purlin profile 132 that
faces in the substantially downward direction "G".
32
CA 02568777 2006-11-23
[0086] The "C"-shaped purlin profile 132 may preferably, but
need not necessarily, be defined by a substantially planar central
purlin base poxtion 134 and two substantially "L"-shaped purlin
portions 136. Each of the "L"-shaped purlin portions 136 may
preferably, but need not necessarily, include a substantially
planar first purlin segment 138 and a substantially planar second
purlin segment 140. The first purlin segment 138 may preferably,
but need not necessarily, extend substantially at right angles from
one respective end of the purlin base portion 134. The second
purlin segment 140 may preferably, but need not necessarily, extend
in a substantially inward direction "E" and substantially at right
angles from the first purlin segment 138.
[0087] As best seen in Figure 3A, neighboring ones of the truss
members 50 may preferably, but need not necessarily, be spaced by a
truss on-center distance "J" in the substantially transverse
direction "B" that is selected from the group consisting of about
36 inches and about 48 inches. Similarly, neighboring ones of the
purlin members 120 may preferably, but need not necessarily, be
sPaced by a purlin on-center distance "K" in a substantially
longitudinal direction "A" that is selected from the group
consisting of about 16 inches and about 24 inches.
[0088] The purlin members 120 operatively support the substrate
sheathing member 26 thereon.
33
CA 02568777 2006-11-23
[0089] In floor systems, the chord base portion 58 of the top
chord 54b may preferably, but need not necessarily, securely engage
the purlin base portion 134 adjacent to one of the notched portions
126. In such floor systems, the chord base portion 58 may
preferably, but need not necessarily, be substantially flush with
the purlin base portion 134. In floor systems, the chord base
portion 58 may preferably, but need not necessarily, operatively
5ubstantially support the substrate sheathing member 26.
[0090] As best seen in Figure 15, the opposing ends 60 of the
central chord base portion 58 of the top chord 54b may preferably,
but need not necessarily, define a concave portion 62 therebetween.
The concave portion 62 may preferably, but need not necessarily,
face in the upward direction "F". The apparatus 40 may preferably,
but need not necessarily, be adapted to additionally include a
predetermined amount 152 of an adhesive 150 operatively interposed
in adhering relation substantially between the concave portion 62
and the substrate sheathing member 26.
[0091) Alternately, and as may be particularly advantageous in
the construction of roof systems according to the present
invention, each of the purlin members 120 may preferably, but need
not necessarily, be shaped so as to define, substantially adjacent
tc) the notched portions 126, a substantially "U"-shaped purlin
34
CA 02568777 2006-11-23
profile 142 that faces in the substantially downward direction "G".
The "u"-shaped purlin profile 142 may preferably, but need not
ilecessaxily, include two purlin side portions 144 extending
substantially at right angles from opposing ends of the purlin base
portion 134. The first purlin segment 138 may preferably, but need
ilot necessarily, extend beyond the purlin side portions 144 in the
downward direction "G". The purlin side portions 144 may
preferably, but need not necessarily, securely engage the chord
hase portion 58 of the top chord 54b. The purlin side portions 144
znay preferably, but need not necessarily, define an up-set portion
(with the terms "purlin side portion" and "up-set portion" being
herein used, mufatis mutandis, substantially interchangeably) that
extends between each of the notched portions 126 and the purlin
base portion 134. In roof systems constructed according to the
present invention, the chord base portion 58 of the top chord 54b
may preferably, but need not necessarily, be operatively vertically
spaced from the substrate sheathing member 26.
10092] The present invention also extends to a method of forming
the apparatus 40 which may preferably include a chord forming step,
a web forming step, a support stiffener forming step, a purlin
sheet forming step, and a purlin forming step.
[0093] In the chord forming step, the top chords 54b and the
bottom chords 54a are roll-formed by passing first elongate sheets
CA 02568777 2006-11-23
(not shown) of light gauge steel material through a series of roll-
forming chord tool sets (not shown). Passage of the first elongate
sheets through each successive one of the chord tool sets
progressively forms the top chords 54b and the bottom chords 54a.
ln the chord forming step, each of the top chords 54b and the
bottom chords 54a may preferably, but need not necessarily, be
roll-formed so that a chord profile of each of the top chords 54b
and the bottom chords 54a defines the "U"-shaped chord portion 56
and the two "L"-shaped chord porti,ons 72. One or more of the
central chord base portion 58 and the chord side portions 64 of
each of the top chords 54b and the bottom chords 54a may
preferably, but need not necessarily, be roll-formed so as to
define a stiffening projection 68 substantially along a
longitudinal extent thereof, The locator apertures 70 may
preferably, but need not necessarily, be punched in the chord side
portions 64 of each of the top chords 54b and the bottom chords
54a. In the chord forming step, the opposing ends 60 of the
central chord base portion 58 of each of the top chords 54b may
preferably, but need not necessarily, be roll-formed to define the
concave portion 62 therebetween.
[0094] In the web forming step, the web members 80 are roll-
formed by passing second elongate sheets (not shown) of light gauge
steel material through a series of roll-forming web tool sets (not
shown). Passage of the second elongate sheets through each
36
CA 02568777 2006-11-23
successive one of the web tool sets proqressively forms the web
members 80. In the web forming step, a locator aperture mating
portion 84 may preferably, but need not necessarily, be punched in
each end portion 82 of each of the web members 80.
[0095] In the support stiffener forming step, the support
stiffening members 100 may preferably, but need not necessarily, be
r.oll-formed by passing the second elongate sheets through the
series of roll-forming web tool sets. Passage of the second
olongate sheets through each successive one of the web tool sets
may preferably, but need not necessarily, progressively form the
support stiffening members 100, such that a support profile 102 of
each of the support stiffening members 100 may preferably, but need
riot necessarily, define the substantially "C"-shaped support
stiffening portion (with the terms "support profile" and "support
:~tiffening portion" being herein used, mutatis mutandis,
substantially interchangeably).
[0096] In the purlin sheet forming step, the plurality of third
elongate sheets 200 (as shown in Figure 16) may preferably, but
need not necessarily, be formed with a plurality of opposed notch
pairs 204 along longitudinal edges 202 thereof. In the purlin
sheet forming step, neighboring ones of the opposed notch pairs 204
may prefexably, but need not necessarily, be spaced by a truss on-
37
CA 02568777 2006-11-23
center distance "J" that is selected from the group consisting of
about 36 inches and about 48 inches.
[0097] In the purlin forming step, the purlin members 120 are
roll-formed by passing the third elongate sheets 200 (as shown in
Figure 18) of light gauge steel material through a series of roll-
forming purlin tool sets (not shown). Passage of the third
elongate sheets 200 through each successive one of the purlin tool
:sets progressively forms the purlin members 120, such that each of
the purlin members 120 has the underside portion 124 that defines
the notched portions 126.
100981 According to this method, each of the web members 80 so
formed is adapted to be operatively secured between one of the top
chords 54b and one of the bottom chords 54a to form the elongate
truss members 50. Each of the web members B0 may preferably, but
need not necessarily, be operatively adapted to extend into each
web-receiving aperture 66, and to be secured to each "U"-shaped
c.hord portion 56, of each of the top chords 54b and the bottom
chords 54a. Each locator aperture mating portion 84 may
preferably, but need not necessarily, be adapted to be operatively
aligned with one of the locator apertures 70 and secured therewith
by a web fastener (not shown). The web-receiving aperture 66 of
each of the top chords 54b may preferably, but need not
necessarily, be adapted to operatively receive two support
38
CA 02568777 2006-11-23
stiffening members 100 therewithin. Each of the support stiffening
members 100 may preferably, but need not necessarily, be
substantially adjacent to the support portions 52. The central
:3upport base portion 104 may preferably, but need not necessarily,
he positioned substantially vertically. The truss members 50 are
securable on the building support members 20. The truss members 50
are adapted to be nested and secured within the notched portions
126 of the purlin members 120. The purlin members 120 operatively
extend in the transverse directiori. "B" relative to the elongate
truss members 50. Each of the purlin members 120 is adapted to
operatively support the sheathing member 26 thereon.
[0099] The present invention additionally extends to a method of
using the apparatus 40 with the building support members 20. This
method includes a truss assembling step, a truss supporting step
after the truss assembling step, an apparatus 40 assembling step, a
gluing step, and a sheathing step after the apparatus 40 assembling
step.
[00100] In the truss assembling step, the truss members 50 may
preferably, but need not necessarily, be assembled, each
preferably, but not necessarily, having the support portions 52
longitudinally spaced from one another, and each preferably, but
not necessarily, being assembled by locating and securing the web
members 80 between the top chord 54b and the bottom chord 54a.
39
CA 02568777 2006-11-23
[0100] In the truss supporting step, the support portions 52 of
the truss members 50 may preferably, but need not necessarily, be
located and secured on the building support members 20. The
(;enters of gravity of the truss members 50 may preferably, but need
not necessarily, be located below the support portions 52. In the
truss supporting step, the load distribution plates 110, securely
engaging the top chord 54b, may preferably, but need not
riecessarily, be substantially securely interposed between the
support portions 52 and the building support members 20. The load
distribution plates 110 may preferably, but need not neoessarily,
be securely fastened, through fastening apertures 3.12, to the
building support members 20.
[0101] In the apparatus 40 assembling step, the truss members 50
may preferably, but need not necessarily, be nested and secured
within the notched portions 126 of the purlin members 120. The
purlin members 120 may preferably, but need not necessarily, extend
in the transverse direction "B" relative to the elongate truss
members 50, so as to preferably, but not necessarily, restrict
sLiding movement of the purlin members 120 in the transverse
direction "B"_ Neighboring ones of the purlin members 120 may
preferably, but need not necessarily, be spaced in the longitudinal
direction "A" by the purlin on-center distance "Kn being selected
from the group consisting of about 16 inches and about 24 inches.
CA 02568777 2006-11-23
[0102] In the apparatus 40 assembling step, for floor systems,
each of the top chords 54b may preferably, but need not
iiecessarily, be substantially flush with each of the purlin members
120.
f0103] In the apparatus 40 assembling step, for roof systems,
the up-set portions 144 of the purlin members 120 -- preferably,
but not necessarily, substantially adjacent to the notched portions
726 -- may preferably, but need not necessarily, engage each top
chord 54b.
[0104] In the gluing step, for floor systems, the predetermined
amount 152 of the adhesive 150 may preferably, but need not
necessarily, be applied to one of the substrate sheathing member 26
and a upward-facing concave portion 62 of the top chord 54b.
[0105] In the sheathing step, the sheathing member 26 may
preferably, but need not necessarily, be supported on the purlin
members 120.
[0106] In the sheathing step, for floor systems, the top chord
54b may preferably, but need not necessarily, substantially support
the substrate sheathing member 26. The predetermined amount 152 of
the adhesive 150 may preferably, but need not necessarily, be
41
CA 02568777 2006-11-23
operatively interposed in adhering relation substantially between
the concave portion 62 and the substrate sheathing member 26.
[0107] In the sheathing step, for roof systems, the top chord
54b may preferably, but need not necessarily, be vertically spaced
1:rom the substrate sheathing member 26_
[010B] The construction of the truss members 50 according to the
present invention is shown in Figure 3, and are shown adjacent to
the building support members 20_ Figure 3 shows the truss members
50 in use with the floor system. The truss members 50 have the
purlin members 120 saddled on top. The sheathing member 26 (i.e.,
floor sheathing) is laid on top of the truss members 50 and the
purlin members 120. The truss member 50 is a Pratt-style truss
member that is supported on the building support members 20 in a
manner that may be best seen in Figures 5 and 6. The truss member
50 includes bottom and top chords 54a, 54b of substantially the
same profile, as well as the web members 90, which have a"C"-
shaped web profile 86. The apparatus 40 also includes the load
distribution plates 110 with pre-drilled fastening apertures 112,
arid support stiffening members 100 which may preferably each take
the form of a short up-right piece of webbing having substantially
the same profile 102 as the "C"-shaped web profile 86. All
elements may preferably be either of welded construction, and/or be
screwed together, andJor be fastened by way of alternate fasteners,
42
CA 02568777 2006-11-23
such as, for example, insert rivets. The bottom and top chords
54a, 54b and the web members BO are provided with the locator
apertures 70 and the locator aperture mating portions 84,
respectively, which are used to locate the positions of the web
inembers 80 relative to the top and bottom chords 54a, 54b.
[0109] The load distribution plates 110 may help to ensure loads
are transferred to supporting structures below the building support
members 20 without substantial localized distortion, and the
support stiffening members 100 may help to prevent the top chord
54b from local collapse as a result of point loads.
L0110] The apparatus 40, including the txuss members 50, is an
open-web assembly. The apparatus 40 is shown in a floor
configuration in Figures 3 and 3A, where the truss members 50 may
preferably be spaced from one another by the truss on-center
distance (as indicated generally by arrow "J" in Figure 3A) of
about 32" or about 48". As may be best appreciated by a person
having ordinary skill in the art upon a consideration of Figure 3A,
the Pratt-style top chord 54b has an inherent resistance to
toppling and/or falling over under concentrated loads, since its
center of gravity (not shown) is below the support portions 52.
[0111] In floor systems, and as best seen in Figure 3A, the
truss members 50 according to the present invention may span from
43
CA 02568777 2006-11-23
the building support member 20 (alternately referred to hereinafter
as a"party wall") to the party wall 20 in an alternating sequence
tiapon the building support members 20_ To accommodate this, it may
have been generally thought, though it is not essential to the
working of the present invention, that each of the truss members 50
may need to carry about twice the normal spans and therefore twice
the loads. It may have been traditionally thought, though again
not essential to the working of the present invention, that with
the installation of 5/8" thick or 3/4" thick sheathing members 26,
the maximum distance between sheathing Support points thereunder
should not exceed about 16" or about 24", respectively. According
to the present invention, by positioning the truss members 50 at
about double the usual spacing, the wall floor junction and bearing
support problems may be overcome. To provide the desired level of
comfort concerning whether adequate support is provided for the
:;heathing member 26 (hereinafter, alternately referred to at the
"sub-floor"), the purlin members 120, having the underside portions
324 with the notched portions 126 spaced therealong, are placed on
top of the truss embers 50, with the top chords 54b thereof nesting
~n the notched portions 126. These purlin members 120
(hereinafter, alternately referred to as "notched purlins") are
shown in detail, inter alia, in Figures 9 and 10_
[0112] Also, though only the top chord 54b is shown in detail in
Figure 7, it should be appreciated that the bottom chord 54a may
44
CA 02568777 2006-11-23
prEferably have a substantially identical profile. The top chord
54b (e.g., as shown in Figure 7) may preferably include, among
other things, the two "L"-shaped chord portions 72, the stiffening
projections 68, and the locator apertures 70 which are used to
position the web members 80 within the top and bottom chords 54a,
54b.
[0113) The notched purlins 1_20 have the "C"-shaped purlin
profile 132 and may preferably be placed structurally in their
weakest axis against loads (not shown) to avoid and/or reduce an
otherwise tendency to twist. Though not essential to the working
of the invention, it is generally thought, that with the notched
purlins 120 placed in their weakest axis against the loads, the
shear center may run substantially directly inline with the load,
such that there may be a reduced tendency fQr the LGS member to
twist. The purlin members 120 according to the invention will
preferably be sufficiently rigid to support the sub-floor sheathing
26. in Figure 3A, the notched purlins 120 are shown in position
over the truss members 50, and may preferably be spaced from one
another by the purlin on-center distance (as indicated generally by
arrow "K") of about 16" or about 24".
[0114) The purlin member 120 which is used in floor systems
(i.e., the floor purlin member 120a best seen in Figure 19) is
fastened onto the top chord 54b by a purlin fastener 130 extending
CA 02568777 2006-11-23
through a fastening aperture 128 in the purlin base portion 134.
The floor purlin member 120a (such as that shown in Figure 17) may
be substantially flat adjacent the notched portions 126,
contributing substantially little or no structural strength in
vertical loadings. This flatness may help to avoid creating a bump
over the top chord 54b, but may or may not be necessary due to its
i_ntended use with features inherent in the sub-floor 26. The
riotched purlins 120 provide the necessary support over the
otherwise unsupported length "J" of 32" or 48", notwithstanding the
flat element directly connecting to the top chord 54b.
[0115] According to one aspect of the present invention, the
truss members 50 may preferably be supported at the support
portions 52 that are located either on the top chord 54b or
substantially adjacent thereto. Such a configuration allows the
truss member 50 to "hang" so as to inherently reduce the chances of
collapse under load conditions and so as to greatly reduce the
secondary installation work that might otherwise be required in
order to stabilize the floor system.
[0116] By spacing the truss members 50 twice the distance apart
from one another, the present invention may provide one or more
significant advantages over prior art systems - possibly making it
easier to install HVAC (heating and air conditioning) components,
as well as electrical and plumbing components. With the truss
46
CA 02568777 2006-11-23
inembers being spaced the distance "J" from one another of 48" on-
centers (hereinafter, altexnately referred to as "OC"), and with
wall studs being spaced from one another at about 16" OC, then in
comparison to prior systems, two of every three prior floor trusses
inay not be required.
[0117] It may be additionally thought, though it is not
essential to the working of the present invention, that the amount
of deflection of the floor truss members 50 may be substantially
cIependent upon the modulus of elasticity for steel, Young's modulus
(i.e., with E approximately equal to about 29,500,000 psi), which
may be much higher for steel than for wood. The comparatively low
modulus of elasticity for wood may mean that a typical 10" wood
floor joist may deflect vastly more than one formed from LGS.
various governmental codes and standards may limit the acceptable
Fimount of deflection for the truss member 50 under the load (not
shown) to the unsupported spanning length (in inches) divided by
360. As a result, it may not be possible, for example, to provide
double spans for most wood applications. As such, the concepts
employed, and the functioning and utilities afforded, by the LGS
construction of the present inventipn do not work the same way for,
and do not have a historical equivalent in, wood applications.
(0118] Various features and capabilities of, and/or advantages
afforded by, the present inventiori -- e.g., alternating spacing of
47
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rhe truss members 50 as shown in E'igure 3A, supporting the truss
members 50 by the top chords 54b on the building support members
20, forming the apparatus 40 from open-web truss members 50 and
notched purlins 120 -- are not present, either on their own or in
combination with one another, in the prior art relating to the
construction industry, and their use in floor and roof construction
may preferably yield considerable cost savings and/or other great
advantages over wood floor joist constructions.
[0119] A typical low rise hotel installation (e.g., about six
building stories) according to the present invention is shown in
Figure 17., where the walls 24 can be seen to divide the structure
into first 25a, second 25b, and third 25c rooms.
10120] One advantage of the apparatus 40, with the notched
purlins 120, may be that the notched portions 126 may be generally
provided at the distance "J" of either 32" or 48" apart.
Accordingly, the notched portions 126 may preferably be used as a
template for measuring the location and distance between adjacent
ones of the floor truss members 50. As such, in use, one may
generally need only to locate a starting point, after which the
measuring tape may be no longer required until completion of the
unit 25a, 25b, 25c.
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[0121] The "hat"-shaped design of the bottom and top chords 54a,
54b, which is best seen Figures 7, 14 and 15, may be relatively
easy to fabricate andJor install. Such "hat"-shaped top chords 54b
have not previously been used with notched purlins 120, and such
ase may results in many benefits.
[0122] A further feature of the top chord 54b, which may be
particularly useful when used in floor systems, is that base
portion 58 of the top chord 54b includes a concave portion 62 (as
l;est seen in Figures 14 and 15). The concave portion 62 is defined
between opposing ends 60 of the base portion 58 and faces in the
upward direction (as indicated generally by arrow "F" in Figure
].4). Through use of the concave portion. 62, a user may control the
thickness of the adhesive 150 (e.g., glue) that is applied.
Typically, as shown in Figure 15, the sub-floor 26 must be glued as
well as screwed to the top chord 54b by a sheathing fastener 28
e:xtending through a chord base aperture 63 in the chord base
portion 58. The glue 150 may help to reduce squeaking that might
otherwise be caused by movement of the sub-flooring 26 and the
surface where the bond is applied. The ability to control glue
thickness, so that the predetermined amount 152 of the adhesive 150
is applied, helps to increase the chances that a minimum amount of
the glue 150 may be applied - i.e., as it might otherwise be
squeezed out leaving no glue between the surfaces.
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[0123] As may be appreciated by persons having ordinary skill in
the art upon a consideration of Figure 15, the use of the notched
purlins 120 may help to provide improved (i.e., reduced) sound
transmission characteristics underneath the floor sheathing 26-
[0124] When used in roof systems, the notched purlins 120
(alternately herein referred to as roof purlin members 120b when
used in such roof systems) 'as shown in Figures 12, 13 and 16 may
preferably include the up-set portion 144. This features may allow
flow of air between the roof sheathing elements (not shown) and the
top chord 54b so as to reduce the likelihood that moisture may
become trapped.
[0125] As shown in Figure 12, the roof system includes top
chords 54b, bottom chords 54a, and web members 80, In prior art
-oof systems, the truss members may heretofore have been spaced at
about 24" OC in order to comply with the maximum allowable
tinsupported span for a typical plywood or OSB board sheathing
material. The top chords 54b in a roof system constructed
Rccording to the invention, however, may preferably be spaced at
4B" OC with notched purlins 120b being spaced at 24" OC whilst
still providing the desired level of support for the roof sheathing
(not shown). Such a construction according to the present
invention may save about 1/2 of the normal trusses which might
otherwise have been installed according to the prior art.
CA 02568777 2006-11-23
[0126] In Figure 13, the root purlin member 120b is shown with
the up-set poxtion 144 being in the approximate order of about
'7/9". Though not essential to the working of the present
Lnvention, it may be generally believed that such an up-set portion
144 may help to improve air circulation in the roof and to reduce
the likelihood of moisture entrapment.
[0117] Various other modifications and alterations may be used
in the design and manufacture of the truss and purlin support
apparatus and in the method of making and using same with building
supports and floor and roof sheathing according to the present
:lnvention without departing from the spirit and scope of the
invention, which is limited only by the accompanying claims.
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