Note: Descriptions are shown in the official language in which they were submitted.
11~'7~1~8
Cross Reference to Related Application
This application is a continuation-in-part of
my earlier filed application Serial No. 457,996, filed
April 4, 1974, now U.S. Patent 3,965,641.
This invention relates to a sheet metal struct-
ural shape and its use in building construction. The
structural shape is particularly useful as a stud or mullion
in wall construction or as a purlin or sub-purlin in deck
construction. This invention includes interior and exterior
building wall construction using the sheet metal structural
shape of this invention. This invention includes interior
deck and roof.deck construction using the sheet metal
structural shape of this invention. "
The wall construction according to this invention
provides erection processes wherein all of the structural
steel, the studs or mullions, may be completely erected
and the wall material applied thereafter from one side.
This is especially
~ ' .
:
.:
~: ~L ' .
- 2
jrr: ~J
~'781Z~ .
important in shaft wall construction where it i~
important to effect early closure of a dangerous open
shaft. Previous methods of~ shaft wall erection,
such as disclosed in U. S. Patent 3,702,044,
require that the c~osure walls and the studs b~
erected together by fitting the wall board ~nto
the slot of the stud creating a dangerous work
environment at the edge of a ~haft.
The structural shape of this invention
is particularly useful as a sub-purlin or purlin
in an insulated roof structure and method providing
superior fire protection and insulation properties.
The deck or roof structure of this invention may
be a poured gypsum or other poured concrete like
deck system wherein gypsum formboard is laid on
novel sheet metal structural shape sub-purlin or
purlin structure. A foamed synthetic organic polymer
board having openings vertically therethrough to permit
moisture from the poured concrete to penetrate to
the gypsum formboard for drying is placed adjacent
and above the formboard. Reinforcing wire mesh, the
poured concrete and a standard weatherproof barrier
is then applied résulting in a unitized structure
affording high strength, high insulation properties,
D-116 3~
. .
~7~
fire resistance and design versatility. Precast
boards may also be used between the structural
shapes for decks according to this invention.
Previously, most efficient lntegral
insulation properties were most frequently obtained
~hen convent~onal metal roof decks were installed
followed by ~oam insulation covered wlth a weather-
proof barrier or traffic layer, such as bitumen and
roofing felt. However, such structures do contribute
to the spread of a fire in a building under such a
metal roof deck. U. S. Patent No. 3,466,222 is
illustrative of recent attemp~s to overco~e such
disadvantages. However, the structure shown in the
3,466,222 patent only slows down fire damage and
does not eliminate it, the roof being susceptible
to total destruction by the foam disintegrating and -
pe1~itting the wea~herproofing matPrials to burn
even when utilizing an expensive metal deck roof
system.
Poured gypsum roof deck systems have long
been recognized as economical and furnishing a fire- -
proof roof structure. In the conventional poured
gypsum roof deck system, gypsum ormboard is la;d over
the steel sub-purlin assembly, a layer of interwoven
D-116 -4~
- . . ., . ~ . .
steel reinforcing mesh placed over the gypsum form- .
board and poured in place slurry of gypsum concrete
applied to conventional two inches thick. Such roof
systems are known to provide satisfactory two hour
fire ratings and low 1ame spread ratings. However,
attempts to provide insulation to such roof deck
systems has not proved satisfactory. One attempt has
been to use perlite a8gregate in the gypsum concrete,
however, this does not give desired însulation properties.
Another attempt has been to provide insulation beneath
the roof deck structure, however, such insulation
either adds to combustion in the interior of the building;
or is expensive if incombustible mineral fiber is used~
Other attempts to provide both satisfactory insulation
and fireproof properties have been to utilize formboard
which is both fireproof and has insulating properties.
Such formboards are those manufactured from ~ineral
~iber materials and fiber glass materials, but these
are both exp~nsive and do not provide the desired
insulation properties while being more difficu~t to
use in field erection.
It is an object of this invention to overcome
the above disadvantages.-
D-116 ~5~
- ~ . . :, ..
~. , .
It is an ob~ect of this invention to provide a
sheet metal structural shape which may be used in building
construction.
It is a further object of thi.s invention to provide
a wall structure utili2ing a series of the metal structural
shapes of this invention especially suitable ~or interior and
exterior.
In accordance with the pr~sen~ invention, there is
provided a sheet metal structural shape for use in building
construction which is symmetrical abou-t a bisecting plane
through a central web having:
a central web;
two diagonal legs projecting downwardly from one
end of the web forming an included angle of about 30 to about
90 between the legs and having its vertex at the bottom of
the web, the diagonal legs having a vertical height of about ~-
1-1/8 to about 10 inches, the vertical height being substantially -
greater than the length of the central web;
each diagonal leg having a leg projecting down-
ward at its extremity in a plane substantially parallel to the
web, the legs being substantially parallel; ~.
each of the parallel legs having a flange
extending outwardly at their extremityi
a closure side extending between the extremities
of the flanges enclosing the area ~ormed by the diagonal siaes,
the parallel sides and the closure side; and
. '
jrr~ 6 -
,
~78~%~3
a stiffening member at the other end
of the web, the stiffening member being narrower than the
flanges and substantially less height than the height of
the diagonal legs.
- 6A -
jrr~
.: : .
~8i~8
These and other objects, advantages and features
of this invention will be apparent from the description
and by reference to the drawings wherein preferred embodi-
ments are shown as:
Fig. 1 is a perspective cutaw~y vlew o:E a double
wall structure of one preferred embodiment of this invention:
Fig. 2 is a sectional view of one embodiment of a
sheet metal structural shape of this invention;
Fig. 3 is a sectional view of another embodiment
of a sheet metal structural shape of this invention;
Fig. 4 is a cross-sectional view of the wall shown
in Fig. l;
Fig. 5 is a cross-sectional view of one embodiment
of an insulated wall according to one embodiment of this
invention;
Fig. 6 is a perspective cutaway view showing a
poured roof deck according to this invention; and
Fig. 7 is a perspec~ive cutaway view showing a pre-
cast slab roof deck according to this invention.
The sheet metal structural shape of this invention
provides excellent structural characteristics while reducing
weight and providing a structural shape which can be readily
fabricated from sheet metal. It is highly desirable to
fabricate structural shapes from sheet metal to minimize energy
; requirements in production and to conserve steel. Prior attempts to
JRR~
- - : . ,, : .
~ 7~Z~3
utilize sheet metal shapes in poured roof construction
have not been satisfactory. Some prior attempts have
utilized sheet metal ~ shapes as substitutes for
bulb tees in roof deck construction. These sheet
metal ~ shapes while providing sufficient strength
in the composite assembled poured roo do not have
satisfactory strength characteristics themselves and
in the erection, bend over ox roll when walked tpon
by the erectors. This results in a very dangerous
situation ~or the workers. The sheet metal structural
shapes of this invention provide desirable strength
characteristics themselves and sufficient streng~h
characteristics to be walked upon during erection
without dangerous bending or rolling.
When used as studs or mullions in wall
construction, the sheet metal shapes of this invention
provide a wall structure wherein ali o~ the studs or
mullions may be erected and ~hen a double wall
applied from one side. This is especially important
in shaft wall construction, such as in elevator shafts.
The sheet metal shape of this invention may also be
utilized for other construction purposes, sùch as
supports for suspended ceilings.
,
-
,
- D-116 -B-
,~- . . . ,
- . . : . . :
.' . ~ -, ' , - : '~ ., . ' :
. ~ . . . : - - ~ . .
. - -. : ~ . : , :: . . . - :
- ~ ,- - . .- - . : ::
~07~
.
Referring to Figs. 2 and 3, the sheet metal
shape of this invention is symmetrical aboue a
bisecting plane through a central web. Shape 13
has a central web ~3 from which two diagonal legs
24 and 25 project downwardly for equal lengths at
an included angle, shown in Fig. 2 as "A", of about
30~ to about 90 between the legs having its vertex
at the bottom of the web, preferably about ~Oc.
Each diagonal leg has substantially parallel legs
26 and 27 pxojecting downward at its lower extremity
at ~he angle "B". Legs 26 and 27 are parallel and
in a plane substantially parallel to web 23. Each
of the parallel legs 26 and 27 have a flange 28
and 29, respectively, extending outwardly at their
extremity. The space between the parallel legs
is closed by side 30. As shown in Fig. 1, side 30 .
is adjacent to flanges 2B and 29.
: Another embodi~ent of the sheet metal
shape of this invention is shown in Fig. 3 wherein
side 30 is spaced from flanges 28 and 29 by box
sides 31 and 32. Box sides 31 and 32 extend from
the extremity of flanges 29 and 28, respectively, in
planes substantiaily parallel to web 23.
. . ,
,
D-116 _g
~, : : .. ... : : , -. , -: - ,... .
-: . -: - - ' - . : . :. - . ,: . : . - ~ -: : :
~O~zs
The upper edge o~ web 23 has a structur~lly
s~ ening member such ~s a flang~, box shape or a
triangle which provide a flat ollter surface at
substantially 90 to web 23. Preferred flange
configurations are shown in Figs~ 2 and 3~ The box
shaped configuration is shown in Fig. lb and the
triangle configuration in Fig. 1 of the parent
application.
~ The structu:ral shape o~ this application
differs from ~he shape disclosed in U.SO Patent
3,965,641 by parallel le~s 26 ~nd 27 and side 30
which closed the space between the parallel legs. :
Parallel legs 26 and 27 provide-greater resistance
to deflection along the plane of web 23 to suit -
desired design characteristics and provide for
arying-wall thicknesses. Closure side 30 results .
in a shape which does not spread as a result of
forces acting upon diags:~nal legs 24 and 25. Closure
side 30 also provides a shape which provides a
raceway for wires, pipes and ~he like~ as well
as ducts for distributing condit-ioned air
throughout a building structure. In cases of use
for air distribu~ion, openings may be cut in desired
locations in closure side 30 and a suitable mani- ..
fcld system located at each end of the shape.
,~ ~, ."i
- 1 0 ~
- . . . - . . : ~ . : . . .::
. .
,
~078~%~3
Flanges ~8 and 29 may vary in length
suitable to hold the desired form~oard or other
decking or facing material. I have found from
about 1/2 to about 1 inch to be suitable. The
height of the diagonal legs 24 and 25 may be varied
to suit the strength requirements of the desired
span. I have found about 1-1/8 to about 4 inches
satisfactory when using the shapes as sub-purlins,
studs or mullions and about 4 to about 10 inches
satisfactory when using the shapes for purlins
or other major structural memberY. The included
angle of legs 24 and 25 is suitably about 30
to about 90~, about 30 to about 60~ being
preferred. Web 23 is important to suppl~
resistance to forces at right angles to the longi-
tudinal axis of the shape and also to prevent
bending or rolling of the shapes whën they are
used in deck structures and walked upon by
erection workers. I have found a suitable
dimension for web 23 is about 3/8 to 5/8 inch,
about 1/2 inch being preferred. The height of
parallel legs may be varied ~o suit strength
require~ents of desired spans. About 3¦8 to about
3/4 inFh is satisfactory wben using tne shapes
' , .
- :
D-116
-
- . . . :: . :: ' ,- :
8~
as sub-purlins, studs or mullions. When using
the shapes for purlins or other major structural
member, the height may be increased to as much
as about 4 inches. - ~
Box sides 31 and 32, as shown in Fig. 3,
may be any suitable length to provide desired
structural characteristics. Box sides of abou~
1/~ to about 2 inches are preferred.
As pointed out above, various forms may
be utilized as stiffeners on the upper edge of
web 23. A preferred shape of sti~fener are
flanges ~1 and 22 extending in opposite directions
at substant;ally 90~ to web 23 as shown in F~g. 2.
The stiffener flanges may be of suitable length
for holding wall board or other facing material.
I have found about 3/8 to about 3/4 inch to be
suitable. When the stiffener is box or triangle
shaped, Lt is preferred that the sides in parallel
planes to web 23 be about 3/16 to about 1/2 inch,
preferably about 1/4 inch when the shape is used
as a sub-purlin or stud and about 3/8 to about
3/4 inch, preferably about 1/2 inch when the shape
is used as a purlin or exterior mullion. It is
preferred the flat portion of the box or triangular
D-116 -12- -
::. .. - - , , ~ . ~ , - , .
~.~7~ 8
stiffener be about 5/16 to about 3/4 lnch;
preferably ~bout l/2 inch when the shape is used
as a sub-purlin or interior wall stud and about
l/2 to about l-l/4 inch, preferably about 3/4 inch
when the shape ~s used as a purlin or exterior
wall mullion. It is desired that the stiffener
shape permit poured concrete or grouting to
flow both under and over the stiffener to prevent
vertical displacement or uplift when the shape
is used in deck construction.
The sheet metal sections o~ this invention
may be fabricated by well known roll forming
techniques from sheet steel from about 12 gauge
to about 25 gauge, about 16 to 20 gauge being
suitable for sub purlins, about 12 to 16 gauge
being suitable for purlins, about 20 to 25 gauge
being suitable or interior wall studs and about
12 to 20 gauge being suitable for exterior wall
mullions.
On'e preferred embodiment of a wall
structure according to this invention is shown in
Fig. l. The wall structure shown in Fig. l i5
especially well suited for interior and shaft walls,
.. ..
The wall structure shown in Fig. 1 spans the
. , , `
.
- - . . ' `' ' ~
' ' , , ' " ' ~ ~'
D-116 -13- ~
- - , : . . ..
' ' ' ' ~ !
~78~LZ8
distance between floors or between a floor and
a oeiling or roof structure. The wall structure
is erected by placing a suita~le anshoring
structure at the base of the wall, such as ~ill
,angle-14, and the corresponding structure at the
;~ ~op or a cap angle. Any suitable shape may be
used which provides a backing against which to
fasten the sheet metal studs 13 and not obstructing
entry of the wall board from the narrow side o~
studs i3. For example, a channel may be used at
the base and an angle at the top. Studs 13,
being of sheet metal, may be readily cut to
suitable length at the job site, erected at
desired spacings and fastened to the sill structure
at the bottom and the corresponding cap structure
at the top. The sheet metal studs may be spot ,
welded or attached in any other suitable fashion
known to the art. It should be noted that in~the
structure of this inventionJ all of the studs
may be put into place at the desired spac7ng
as soon as the sill and cap structures are
installed, thus, affording quick and safe pro- ;
tection of open shafts and the like. The studs
may be co~pletely installed from the building side
,
'. ` ` , ~` ~ ~ . .
., ` ' , '- ' ~ ' . '~' .
.
,
D-116 -14-
~0783~
o~ ehe shaft without the necessity ~or scaffolding
or even leaning into the shaft area~ After the
spaced studs are erected, the inner shaft wall
filler board 12 may be attached to the studs
from the building si~e of the shaft simply by
placing the wall board against the flanges o
the studs as shown in Fig. 1 and applying screws
shown as 16 at desired locatio~s through the
inner `shaft wall and into the stud flange.
While Fig. 1 shows the use of the shape as shown
in Fig. 2, the shape shown in Fig. 3 may be used
Pqually as well and i~ the same manner w~th the
advantage that the screws are completely within
the box section of the structural shape.
Outer shaft wall il may be applied by
placing the ou~er shaft wall board in ~he desired .
position and applying screws or other fastenin~s
through ~he outer shaft wall board and the fla~
portioQ of the stiffener structure of the stud.
Thus, the entire double wall assembly may be
completely assembled from one side.
A preferred embodiment of a shaft wall
is shown in ~ig. i wherein the studs are spaced
on centers of ~he width of standard aYailable.wall
.
'
~-116 -15- - -
' ' :. , ' ~ , -. ' ' . :
~)781Z8
. . .
board. The inner shaft wall board 12 is cut
narrower than the ~uter shat wall board 11 to
provide insert 17 which fits between the parallel
legs 26 and 27 of the structural shape thus
providing additional fire resistance to the wall
structure. Of course, the space between inner
shaft wall i2 and outer shaft wall 11 may be
filled with any type of insulation material
desired. The wall closure material fastened to
the flanges of adjacent structural shapes may
be of any suitable material. As shown in
Fig. 1, with particular reference to sha~t
wall construction, gypsum board may be used
in interior construction. Alternatively, ply-
wood, various composition boards, metal panels
and a wide variety of composi~ion panels with
various desired interior surface finishes 9 may
be used to obtain texture, color and acoustical
properties. The wall construction of this
invention is also suitable for exterior walls
and in such cases, the wall closurc material
facing the exterior would suitably be a weather~ ;
resistant material and may be faced with any
desired texture or colored material to obtain
.
- - ,
, .
D-116 - -16-
.. ... . . ... .......
- . . .
- : . . . : .
:..,.,::^. . ...
,
~ 078~Z8
the desired appearance. For example, Venetian
corru~ated metal ~ich is available in long roll~
and surfaced in a variety of stone and brick
textures may be readily cut to length at the 30b
site snd applied wi_h self-tapping screws.
- For exterior wall construction, the
thickness of insulation between the inner and
outer wall closure material, shown as 34 in F~g. 5,
may be of any desired thic~ness by utilization o~
iller blocks 36. Also, in exterior construction
as well as interior, the structural shape of this
inve~tion may be filied with any suitabl~
insulation material or may be filled with gypsu~
concrete to provide added fire resistance~
~ G~hc17.
shown as 35 in Fig. 5~ When utilizing the
building wall structure of this invention for
exterior walls, it is preferred to use the
embodiment of the structural shape shown in - ;~ -
Fig. 3 for added strength. Thus, either single
or double wall construc~ion may be readily
obtained by use of the sheet ~etal str~1ctural
shapes according to this invention.
It is readily apparent that when the
wall structure, as described above, i~ erected
'~' ' , ' ' ' ' ' '"
,
.
D-116 -17-
~ ~ , . - ~ . .. . ...
~C178~L2~3
in horizontal or near-horizontal planes, the structures
provide a sui~able building deck structure. Thus, a
building deck structure may be obtained by simply utiliz- -
ing suitable materials in the decking a.ssembly to provide
a suitable ceiling structure shown as 12 in Fig. 5, suit-
able insulation, if desired, shown as 34 in Fig. 5, and a
suitable floor structure shown as 11 in Fig. 5, the deck-
ing assembly made up of the ceiling structure 12,
insulation 34 and floor structure 11, may be prefabricated
and set in place as a unit using fasteners 15. In such
case, fasteners 16 may be eliminated or, if desired, driven
from the opposite direction then shown in Fig. 5. For
interior decks, the ceiling structure 12 may be any suit-
able acoustical material while the deck surface structure
11 may suitably be plywood with polystyrene or polyure- ~
thane foam between. -
The sheet metal structural shape of the present
invention may also be directly substituted for the struct-
ural shape disclosed and claimed in my parent application,
Serial NO. 457,996, now U~S. Patènt 3,965,641, for use
in both poured concrete
,
- 18 -
j rr O /!3-
~
.
., ~ , . , , . . , , .~ . . . . .. . .
. ~
. , . - . . ,-, ; . -
. . . . . , , : . . . ~ -:
- .
~7~
deck structures, as illustrated in ~ig. 1 of that patent, or
in prefabricated or precast roof structures as illustra;_ed
in Fig. 2 of U.S. Patent 3,965,641.
The structural sheet metal shapes 13 and 33 of
this invention may be used ~s sub-purlins and supported by
any suitable structural members such as open web joists and I
beams spaced at proper intervals, making a suitable roo:~
support member system as shown in Figs. 6 and 7. Any roof
support member system suitable for support of a poured roof is
satisfactory. Gypsum formboard 112 having a desired thickness
of synthetic organic polymeric foam 113 may be placed in
contact with the upper side of the gypsum formboard, the g~-psum
formboard resting upon the flanges 28 and 29 of adjacent
structural sheet metal shapes of this inven~ion. It is des- :
ired that the polymeric foam have openings of more than about
5 percent of the area of the polymeric foam, preferably about
5 to 20 percent of the surface area of the polymeric foam
providing communication between the volum~
' ' .
.
-- 19 --
~ . ,
rr~
10~812#
above the polymeric foam to the upper sur~ace
of the gypsum formboa~d. Conven-tionally used
wire reinforcin~ mesh~is placed above the
/~
polymeric foam and concrete~poured eO a desired
thickness above the polymeric foam, the
concrete extending through the above mentioned
openings in the polymeric foam to contaet the
gypsum formboard and the poured concrete flowing -
~7
both under and over the stiffening member~o~
the.sheet metal structural shape o~ this
invention, thereby p~ovidi~g excellent upli~t
resistance and a composite roof structure.
Any gypsum formboard providing a two hour
ire rating when used with poured gypsum slabs is
suitable. The least expensive of the gypsum formboards~
the rigid one-half inch thick gypsum form~oard i~
suitable for use in the roof structure of this inven-
tion, however, various surfaced gypsum formboards
having suitable ceiling surfaces may be utilized as
long as the incombustibility and flame spread rating~
are satisfactory~ .
The synthetic organic polymer foa~ may be
any substantially rigid organic polymer foam having
good insulating properties and preferably a high
. '
--' ' ' ~ ' ' ' ' -
.
D-116 ~20-
~L~7~3~Z~
temperature at which thermal decomposltion occurs.
Suitable foams include polystyrene, styrene-maleic
anhydride, phenolic, such as phenol formaldehyde,
polyurethane, vinyl, such as polyvinyl chloride and
copolymers of polyvinyl chloride and polyvinyl
acetate, epoxy~ polyethylene, urea formaldehyde,
acrylic, polisocyanurate and the like. Preferred
foams are selected from the group consisting o~
polystyrene and polyurethane. Particularly suitable
foams are closed cell foams which provide high
insulating properties and low internal permeability
to moisture. Such organic polymsr foams are substan-
tially rigid bodies o foam and are well known for
thèir low density and outstanding thermal insulatî~g
properties. Previously, use of organic polymer foam~
in roof structures has been limited due to the need
. .
; for care and special attention in installation if
they are used alone and due to their decomposition
at higher temperatures perm;tting structural damage.
In accordance with this invention these disadvantages
are overcome and polystyrene may be advantageously utilized.
; The organic polymeric foam and the gypsum
formboard may be preassembled by fastening the foam
,'-.
. ' ' ' '- ' ' . ', ' ' '
" , - ' ' , ' ' '"
D-116 -21-
- - , -: . . . . , .. ... . ~ . . .. : :
- - . - . . , . ,~
- .. . - , - ~ .. , :- .. . . : .. - .. - . :
0 7 611Z~3
to the formboard by an~ suitable fastening means.
Suitable fastening means include synthetic and natural
adhesives, wire staples, metal clips and the like.
Suitable synthetic adhesives include epoxy, polyure-
than, polyamide and polyvinylacetate and its co- ~
polymers. Adhesives and wire staples are preferxed.
The polymer foam and gypsum formbnard may also be
readily assembled at the construction site by first
laying the formboard in place and placing the ~oam
on top o it in a fashion to hold the foam the desired
distance from the novel purlins. ~
Following installation o the gypsum form-
board - polymer foam, standard reinforcing wire mesh
used in poured gyps~m deck assemblies, shown asll4 i&
applied and gypsum concrete poured to a suitable
. .
thickness of about 1-1/2 to about 3 inches over the
surface of the polymer foam, about 2 inches being I -
preferred. The poured gypsum concrete flows
through openings in the polymer foam and
adheres to the upper surface of the gypsu~ board
12. This structure provides an integral roofing
structure having desired fireproof ana internal
insulation properties.
._ - - ' - - - ~- ' , ;'.
.
.
: '' ' . , ' . .
- , ,
. D-116 -22-
-: : - : - : : : : -~ : .
~078~L28
The gypsum concrete utili7Pd may be preferably
standard gypsum concrete. However,modif~ed concretes
contalning various fillers, such ~s perlite, aggregate
for thermal insulation and lighter weight are suitable,
or exploded mica in portland cement is suitable, but
not necessary in the roof structure of this invention.
The gypsum concrete is especially desirable for use in
roo~ structures not only because ït is incombustible
but also because the gypsum sets within a ~ew minutes ___
to form a slab that is hard enough to walk upon there-
by permitting, in many cases, a waterproof wearing
surface to be laid the same day the slab is poured.
When any type of portland cement is used, the setting
time is much slower and to prevent moisture from sagging
the formboard, I have found it necessary to place a
moisture permeable sheet between the cement and the
top surface of the formboard. I have ound that moisture
permeable paper, such as gypsum board paper, preferably
placed on top of the foam is satisfacto~y.
A built up roofing membrane comprising
alternate layers of roofing felt~and hot asphaltAmay
be applied on top of the concrete with a waterproof
wearing surfnce of tar and gravel. Any suitable
waterproof wearing surfaee for flat type roofs i~
':
.
. . - ~ I
,: , . . ' ::
~ ' ' ': ' " '~.
D-116 -23-
... . _ .
. . . - . -
~07~ 8
suitable ~or this roof structure of thls invention,
or the gypsum concrete may be waterproofed with ',
a plastic membrane, such as on d~me-type roof
structures.
The drying of the concrete continues by
removal of moisture from the concrete for several
weeks a~ter pouring. I have ~ound that in using the
roof structure of this inven,tion,the drying time of j'
the concrete is not greatly increased. Thi~ results
rom the concrete being,in communication throu~h hales .
in the polymer foam with the gypsum formboard which ;
i5 porous to water. The drying of the concrete after
a built-up type roo~ing membrane is applied to it~ r
exterior continues by the moisture esc~ping through
.. , I
the formboard. ~,' , I
The roof structure of this in~ention provides
properties ~hich are presently being called for by
. ! '
newer building regulations. The first such propert~ -
is fire ratings which~ following suitable AST~ testin~,
result in two hour fire ratings for the roof structure.
The second important property is thermal insulation
combined with the s'ati'sfactory fire rating. Present
.. , j
energy conservation eo~siderations result in a l'U'1 i
value of 0.10 and less being desirable~ Calculations , , ~
show that roof structures of this invention utilizing , ~'
the sheet metal shape as a purlin and using polystyrene , '
'. . ..
, . -
' ' ` ' ' ' ' , ', , ',:
D~ 24- '
- .. :: - : . . - ,, - - . :: . . . ~ . -
- -; - . - - ., - - . , . . - . . . ~ :: , . . . . . . :
., - . - . ... . :. . : -, . . . - . .. . ... . .......
: .
- . ~. : , . .. ..
. . ~ .. . . .
10781ZB
and gypsum concrete result in "U" values of 0.06 and
les~. When the sheet metal shape is utilized as ~
sub-purlin with 1/2 inch gyps-~ formboard, 1-1/2 inch
polystyrene foam board and 2 inch gyp~um concrete the
"U" value ~s 0.10. Thus, an inexpensive deck is
provided having both a two hour fire rating for
Class 1 fire rated construction and insulation
properties resultin~ in "U" values of 0..10 and less.
Further, a range o~ desired insulating properties may
be achieved by varying the thickness of the synthetic
polymer foam.
Any suitable ceiling s~ructure may be installed
beneath the roof structure of this invention as long
as suitable ventilation is furnished. However, in
contrast to prior roof structures, it is not necessary
~hat the ceiling provide the insulation or fireproofing .
~ualities. The roof structure of this inventio~
provides high insulation and fireproof properties with-
ou~ any structure beneath it and may be left exposed.
Further, when the sheet metal shape of this inventio~ -
is used directly as a purlin, about one foot of interior
occupanoy space is gained over conventional constructio~
using exposed jois~s which mus~ als~ be fireprooed
The sheet metal shapes of this invention may
also be utilized in roof deck construction utilizing
' .`~
D-116 . -25~ ~
~ .
,. . ~ .
' . : ' -
- : ;,
~7~1Z~3
precast fireproof and insulating slabs such as fibrous
materials bonded with hydraulic cement binders as shown in
Fig. 7. The slabs may be laid on flanges 28 and 29, of the
sheet metal shapes 33 and the space between the slabs and
the sheet metal shapes is covered rom the top with grout
118. Any precast slab affording suitable fireproofing and
insulating properties is suitable for use in the deck of
this invention.
While in the foregoing specification this invention has
been described in relation to certain preferred embodiments
thereof, and many details have been set ~orth for purpose
of illustration, it will be apparent to those skilled in
the art that the invention is susceptible to additional embodi-
ments and that certain of the details described here.in can
be varied considerably without departing from the basic
principles of the invention.
JRR:~C_ -~26 -
' ""
... .. . . . .. .
.-- ~ . . .
- ~, .. . . . .
