Improvements in Fire Proof Structures for Ceilings, Floors, and Roofs.
Year: 1893

page_text: Date of Application, 21st June, 1893
Complete Specification Left, 5th Mar., 1894-Accep ed, 7th Apr.. 1894
PROVISIONAL SPECIFICATION.
Improvements in Fire Proof Structures for Ceilings, Floors,
and Roofs.
1, THOMAS LEWIS BANKS, of Holmrook, Cumberland, F.R.I.B.A., do hereby
declare the nature of this invention to be as follows:-
My invention relates more particularly to that construction of fire proof ceilings,
Hoors, and roofs in which a layer of concrete is supported between metal girders or
joists or other lateral supports by means of metal supports which are carried by the
girders or joists.
According to my present improvements I construct such metal supports as
follows.
An arched bar of any desired section has its ends tied together by a horizontal
tie rod, and from any number of points in the length of the arched bar are suspended
metal strips or rods arranged so as to either turn on or slide along their point of
suspension and having their lower ends either looped or formed as hooks or otherwise,
so as to support the horizontal tie bar on its underside without being actually fixed
thereto. Such arched structures being placed with their ends upon the girders
joists or other lateral supports, and the arched bars being covered over with either
expanded metal, metal laths or sheet metal, the concrete or, in the case of roofs,
asphalt or other waterproof raterial is then laid on to such covering. This load
on the arched bars may cause them to be deflected to a slight extent, whereby the
suspension strips or rods, in sinking with it, will move with their hooked or looped
lower ends to a corresponding extent away from the tie rod, which will consequently
remain horizontal. The suspension strips, if pivoted to the arch bar at their upper
ends, then have their lower ends slid laterally along the tie bar until by the augular
position assumed, they again come in contact with the tie bar with their loop or hook,
and thus again support it in its horizontal position, so that the covering for the ceiling
can be then attached to it without causing it to deflect. If the suspension strips
are merely hooked on to the arch bar at their upper end, then they are slid at both
ends towards the centre.
The suspension strips or rods may, if necessary, be secured in such adjusted
positions by clips, keys or other suitable means.
The ceiling suspended from the said tie rods may be of any known fire proof
construction, or of the construction, in which loops or eyes are suspended by
a hooked stem from the tie bar metal rods being passed through the eyes, and
upon such rods is laid expanded or other metal lathing for receiving the plaster
ceiling.
Another improvement relates to the construction of trimmer arches for such fire
proof floors or ceilings. I construct such trimmer arches of expanded metal or
other metal lathing, which is bent up at such an angle on each side as to fit
against the correspondingly angled surface of the skewback of the wall on the
one side and the feather edged piece of the trimmer joist on the other side, and the
metal so prepared is supported by correspondingly shaped cross bars of iron or
strips of wood, which latter can afterwards be removed.
The first coat of plaster having first been, by preference, applied to the upper
side of the metal lathing and allowed to harden, the concrete is then laid on and in
hardening forms a solid arch united to the metal lathing, which arch is held in
position by the wedge shaped form of the before mentioned sloping sides.
Dated this 21st day of June 1893.
ABEL & IMRAY,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Fire Proof Structures for Ceilings, Floors,
and Roofs.
I, THOMAS LEWIS BANKS, of Holmrook, Cumberland, F.R.I.B.A., do hereby
declare the nature of this invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:-
My invention relates more particularly to that construction of fire proof ceilings,
floors and roofs in which a layer of concrete is supported between metal girders or
joists or other lateral supports by means of metal supports which are carried by the
girders or joists.
According to my present improvements I construct such metal supports as
follows:-
An arched bar of any desired section has its ends tied together by a horizontal
tie rod, and from any number of points in the length of the arched bar are suspended
metal strips or rods arranged so as to either turn on or slide along their point of
suspension and having their lower ends either looped or formed as hooks or
otherwise, so as to support the horizontal tie bar on its underside without being
actually fixed thereto. Such arched structures being placed with their ends upon
the girders joists or other lateral supports, and the arched bars being covered over
with metal lathing or sheet metal, the concrete or in the case of roofs, asphalt or
other waterproof material is then laid on to such covering. This load on the
arched bars may cause them to be deflected to a slight extent, whereby the
suspension strips or rods, in sinking with it, will move with their hooked or looped
lower ends to a corresponding extent away from the tie rod, which will consequently
remain horizontal. The suspension strips, if pivotted to the arch bar at their upper
ende, then have their lower ends slid laterally along the tie bar until by the angular
position assumed they again come in contact with the tie bar with their loop or
hook and thus again support it in its horizontal position, so that the covering for
the ceiling can be then attached to it without causing it to deflect. If the
suspension strips are merely hooked on to the arch bar at their upper end, then
they are slid at both ends towards the centre.
The suspension strips or rods may, if necessary, be secured in such adjusted
positions by clips, keys or other suitable means.
Fig. 1 of the accompanying drawing shews a section of a fire proof floor having
arched supports constructed according to my above described invention. Figs. 2
to 5 shew enlarged details thereof. The floor is constructed in a similar manner to
that described in the Specification to my Application No. 10,044 of 1893 that is to
say, upon the metal joists A are placed the arched supports B B' B' the arched
upper surface of which is covered by sheet metal or metal lathing C, on which is
laid the concrete D. From the tie bar B' of the support are suspended eyes E
through which are passed rods F serving to carry metal lathing G on which the
plaster ceiling is laid.
The suspension bars B' that carry the tie bar B' either have both ends bent into
book form as shewn more clearly at Figs. 2, 3 and 4, the upper hook being hung on
to the arched bar B, while the lower hook supports the tie bar B'.
On the arched bar B being loaded with the concrete as described, it will be
somewhat deflected, whereby the lower hook of B will be made to sink away from
the bar B', to a slight extent as indicated at Fig. 4, whereupon the bar B2 is driven
along the arched bar and the tie bar in the direction of the arrow, until, owing to
the rising curvature of B, the lower 1 op of B' is again made to fit tightly against
the lower edge of B¹. Fig. 5 shews the arrangement in which the suspension
bur B is fixed to B by a bolt or rivet. In this case, when the bar B has been
deflected by the load, the lower end of B2 is driven forward into such an angular

page_text: position as to cause its hook to be again tightly engaged with the bar B', as
indicated by the dotted lines.
It will be seen that by these means any sagging of the bar B' and consequently
of the ceiling is effectually avoided, and also, that should a fire occur which would
heat the tie bar B' to such an extent as to soften it, it will still be effectually
supported and prevented from dropping, by the fact that the arch bar B from
which it is suspended is removed by the intervening air space a considerable distance
from the flames and is thus prevented from being injuriously heated.
Another improvement relates to the construction of trimmer arches for fire proof
floors or ceilings. I construct such trimmer arches of metal lathing as I will
describe with reference to Figs. 6 and 7 of the drawings. A sheet of metal lathing,
by preference of a kind consisting of interlaced twisted strips of metal, is bent up
at such an angle on each side as shewn at H H Fig. 6 as to fit against the
correspondingly angled surfaces of the skew back of the wall, as at I Fig. 7 on the
one side, and the feather edged piece J' of the trimmer joist J on the other side,
and the metal so prepared is supported in the position shewn by correspondingly
shaped cross bars of iron or strips of wood, which latter can afterwards be
removed.
The first coat of plaster having first been, by preference, applied to the upper
surface of the metal lathing and allowed to harden, the concrete K is then laid
on, and in hardening forms a solid arch united to the metal lathing, which arch is
held in position by the wedge shaped form of the before mentioned sloping sides.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is :-
:-
1. In fire proof structures for ceilings floors and roofs, the use of arched
supports B B B the suspension bars or rods B2 of which are formed with looped
or hooked ends embracing respectively the arched bar B and the tie bar B¹, so that
when the former is deflected by the weight of the concrete filling, the suspension
bar B can be deflected without deflecting the tie bar, and can then be shifted in
position so as to be engaged tightly with the tie bar again, and thus retain it in its
horizontal position while on the occurrence of fire it is also effectually supported
by the arch bar B against dropping when heated, owing to the latter being
separated some distance from the fire by the intervening air space and thus
prevented from being overheated substantially as described.
2. In arched supports such as are referred to in the preceding claim, connecting
the suspension bars or rods B' to the arched bar B by a pivotable connection while
the lower end supports the tie bar by a loop or hook, substantially as and for the
purposes described.
3. Constructing trimmer arches for fire proof floors of a sheet of metal lathing
having its two sides bent up to an angle corresponding to that of the skew back
at the feather edged piece of the trimmer joist, which metal lathing is then filled
in with concrete substantially as described.
Dated this 5th day of March 1894.
ABEL & IMRAY,
Agents for the Applicant.