Improvements in Fire-proof Floors and Ceilings.
Year: 1895

page_text: Date of Application, 25th Oct., 1895-Accepted, 30th Nov., 1895
COMPLETE SPECIFICATION.
Improvements in Fire-proof Floors and Ceilings.
I, ALFRED GEORGE WRIGHT of 53 Victoria Street, Westminster, Engineer
and Iron Founder 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 mainly to fire-proof flooring constructed of steel or iron
and concrete, and consists in using flat bars of metal placed on edge between and
alternating with curved or arched plates or sheets of metal, by preference
corrugated, forming a permanent centering or soffit for concrete and resting upon
metallic joists or girders so that the said bars shall form supports of a ceiling
suspended below the joists or girders and so that the upper parts of such bars shall
be supported and stiffened by the abutting arched plates and concrete especially
near the centre of their length as herein described.
The method of construction is shewn in the drawings annexed hereto in which
like letters of reference indicate similar parts in the several views.
Fig. 1. is a vertical section through the floor;
Fig. 2. is a perspective view with portions of the flooring removed; and
Figs. 3 and 4 are views of the hooks or hangers supporting the ceiling, drawn to
an enlarged scale.
A, A are flat bars of metal placed on edge and resting at their ends upon the
metallic joists or girders C, C and by preference having their lower edges cut or
bent to fit in the root of the joists C, Č.
B, B are curved or arched sheets of corrugated metal, resting upon the said
jcists or girders C, C, and abutting against and alternating with the said flat
bars A, A.
D is a filling of concrete upon and about the said sheets bars and joists formed
with a level top surface which may be used as the floor surface or may support
wood flooring as shewn or any other suitable covering.
F, F are hooks or hangers passing through slots or apertures in and near the
lower edges of the flat bars A, A, and supporting bars or tubes of metal G, G
which in turn support the woven wire-work or metallic lathing H by means of wire
conrections in the usual way.
Upon this wire-work or metallic lathing the plaster ceiling J is formed; or
otherwise a ceiling may be formed on wood lathing nailed to wood ceiling joists in
which case the lower parts of the aforesaid hooks or hangers are suitably formed
to receive and support such ceiling joists.
By preference the hooks or hangers are made of such length as to allow an open
space for the circulation of air between the undersides of the metallic joists or
girders and the plastered ceiling.
The arched plates or sheets B and the concrete D abutting against the flat
bars A maintain the said bars in their upright position and support and stiffen
them laterally especially near the centre of their length and at their upper parts
where compressive stresses are caused by the weight of the ceiling supported by
them so that the tendency of the said bars to buckle or bend laterally at the top
is opposed and counteracted.
I prefer to make the hooks or hangers of flat steel or iron bars bent to shape
and passing through elongated holes or slots in the flat bars A as shewn more
particularly by the enlarged views Figs. 3 and 4 and by these means the vertical

page_text: sectional area of the flat bars A is less reduced by the necessary apertures than
would be the case if hooks or hangers of equal strength but formed of round or
square metal were used.
Where the space covered by the floor is narrow as in corridors and passages the
metallic joists or girders may be omitted and the flat bars and arched sheets may
be carried in one span from side to side of such space.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. Floors constructed of flat metal bars placed on edge between and alternating
with curved or arched plates or sheets of metal corrugated or otherwise and
covered with concrete substantially as herein set forth.
2. Ceilings supported by hooks or hangers from and below flat metal bars
placed on edge such flat bars being supported laterally near the centre of their
length and at their upper parts by arched metal sheets or plates and concrete
substantially as herein set forth.
Dated this Twenty-fifth day of October 1895.
ALFRED G. WRIGHT.