Improvements in or Connected with the Construction of Roofs for Buildings.
Year: 1889

page_text: Date of Application, 19th Feb., 1889
Specification Accepted, 30th Mar., 1889
COMPLETE SPECIFICATION.
Improvements in or Connected with the Construction of Roofs for
Buildings.
I, CHARLES CARROLL GILMAN of Eldora, Iowa, in the United States of America,
Manufacturer of porous terra cotta 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 :-
$1
My invention involves the use of porous or cellular terra-cotta, otherwise known as
terra-cotta lumber," or any other porous burned brick material; and it consists in
combining this material with other essential elements or parts of the construction to
form the roof of a building or other structure.
In the accompanying drawing, which forms a part of this Specification, is represented
a perspective view of a roof embodying my invention.
Terra cotta lumber or porous burned brick, as is well known, is a noncombustible
material which more effectually resists the action of fire than brick, is to a very high
degree a nonconductor of heat and cold, and also of sound, is a good nonconductor
of electricity, is easily wrought with edged tools, and will receive and hold nails.
This material so apply in the construction of roofs as to cover or enclose the
wood work thereof and thus effectually protect the same against destruction by fire
and prevent the penetration of heat or cold into the interior."
Referring to the drawing, P represents the rafters, to which I nail or otherwise
secure, in lieu of the boards usually employed, slabs S of terra cotta lumber, from
two or three inches in thickness and in length corresponding to the distance from
centre to centre of the rafters, preferably twelve inches. Slates, tiles, metal sheets
or shingles T, first lightly bedded in mortar U, or in a covering of cement or
Wooden shingles
bituminous mastic, are subsequently nailed to the said slabs.
bedded in lime mortar which have been in place for a year can be detached from
the slabs only with great difficulty, the shingle, mortar and slab having apparently
become one solid mass. The tightness of such a roof, its impenitrability to heat or
cold, and the impossibility of burning it by outside application is evident.
To fairly fireproof the inside of the roof and to provide an additional barrier to the
penetration of heat or cold, ceiling slabs W, one or one and one half inch in thickness,

page_text: are mailed to the underside of the rafters, and subsequently plastered. The spaces
existing between the inside and outside sheets of terra-cotta lumber afford air-
chambers in depth equal to that of the rafters employed, and thus the garret can
be made the coolest room in the building. This result is due not alone to the air-
chambers, but also partly to the fact that the terra cotta lumber is a very bad conductor
of heat and cold.
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 1
claim is
1. The combination with the rafters, of slabs or sheets of terra cotta lumber secured
to the same and a layer of cement or its equivalent applied to the outer surface
thereof, substantially as described.
2. The combination, with the rafters, of slabs of terra cotta lumber secured to
the same and a covering which protects the said slabs from the action of the
weather and renders the roof watertight, substantially as described.
3. The combination, with the rafters, of slabs or sheets of terra cotta lumber secured
to the same a layer of cement or its equivalent, and an outer covering of slate or
shingles bedded in said layer, substantially as described.
PATCH
cum דמחוז מ 16 T 165 מעז. door,
C. C. GILMAN.
By Brewer & Son,
33, Chancery Lane, London,
Agents.