IMPROVEMENTS IN ROOFS AND IN OTHER STRUCTURES WHERE TIMBER SHEATHING IS USED
Year: 1876

page_text: LETTERS PATENT to William Henry Kershaw, of Widnes, in the County of
Lancaster, Timber Merchant, for the Invention of "IMPROVEMENTS IN ROOFS
AND IN OTHER STRUCTURES WHERE TIMBER SHEATHING IS USED."
Sealed the 1st June 1877, and dated the 1st December 1876.
PROVISIONAL SPECIFICATION left by the said William Henry Kershaw
at the Office of the Commissioners of Patents on the 1st December 1876.
WILLIAM HENRY KERSHAW, of Widnes, in the County of Lancaster, Timber
Merchant. "IMPROVEMENTS IN ROOFS AND IN OTHER STRUCTURES WHERE TIMBER
SHEATHING IS USED."
This Invention relates more especially to timber roofing for chemical works and
other similar structures; it consists in making boards with a small flange on each
side of the board, one at each edge, alternating with each other. These are made
usually of 2-inch plank, a half-inch board being sawn out of each side, leaving a
strip at the end not sawn off. These boards, which from their shape I will call
Z boards, are placed with the flanges interlocking. Each therefore keeps up
the one next below it (the upper side having the flange pointing up, the lower
pointing downward). Between the two flanges I sometimes place a piece of hoop
iron, the edges of which can be embedded, if desirable, in the slight groove made
by the circular saw in detaching the half-inch board.
The Z boards are screwed or bolted to the purlines or otherwise attached, so
that they can be taken down easily. At their ends they are jointed to the next
board in any convenient manner; I prefer the following: A metal plate is
inserted into a longitudinal groove in the end of each Z board and the space
above, and occasionally that below also filled in with any suitable water-tight
cement.
This apparatus can be used for sheathing for walls as well as roofs, and can be
made of metal, clay, or other suitable material; if made of wrought iron it is usually
rolled into the Z shape, or by very simple machinery be bent up at the edge; if of
wood, it is usually kianized.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Henry Kershaw in the Great Seal Patent Office on the
1st June 1877.
WILLIAM HENRY KERSHAW, of Widnes, in the County of Lancaster, Timber
Merchant. "IMPROVEMENTS IN ROOFS AND IN OTHER STRUCTURES WHERE TIMBER
SHEATHING IS USED."
This Invention relates more especially to timber roofing for such large sheds as
are used in chemical works and other similar structures; it consists in making
boards with a small flange, either one on each side, or two on one side of the board,
at the edge of it, the flanges usually alternating. These are made of a plank
suitable in thickness to the strength of board required, the timber being so sawn
out that it leaves a flange at the end not sawn off. These boards, which from
their shape I will call Z boards, are placed with their flanges interlocking. Each
therefore when placed longitudinally on the roof keeps up the next one below it,
the upper side having the flange pointing up, the lower pointing downwards.
Between the flanges I sometimes place a piece of hoop iron, the edges of which can
be embedded, when desirable, in the groove made by the circular saw in detaching
the timber, and made water-tight with white lead or other composition.
The Z boards are screwed, nailed, or bolted to the purlins or otherwise attached,
so that they can be easily taken down. At their ends they are jointed to the next
board in any convenient manner; I prefer the following-A metal plate is
inserted into a, groove shaped to the board at the end of it, and the space above,
and occasionally that below, filled in with any suitable water-tight cement.
This apparatus can be used for sheathing for walls as well as roofs, and can be
made of metal, clay, or other suitable material; if made of wrought iron it is usually
rolled into the Z shape, or by very simple machinery bent up at the edges; if of
1. ovented
Figure 1 is a plank cut to the required shape with the pieces cut off, shown in 3
position; the cuts are made by circular saws projecting above the table to the
required height only; Figure 2 is a roof made of plain Z boards.
In these A is the roof board; B, the selvage cut off; D, hoop iron.
Figures 3, 4, and 5 represent modifications of this arrangement. The lower part
of board, Figure 5, is formed by sawing two out of one plank with a level cut 3
between them, as shown in Figure 11.
Figure 6, a plank shown with the spare pieces cut out from it by a sawing
machine of my own Invention, and for which I have made application for Letters
Patent; Figure 7 shows a longitudinal section of a roof made entirely of these
planks, they being arranged to slope each way from the apex, instead of, as in the 4
Z boards, running longitudinally with the roof.
Figures 8, 9, and 10 are three modes of joining the boards, in which K is a plate
of sheet lead, cast iron, felt, or other material; and L, asphalt or other coun-
position.
Having now described my Invention and the best mode known to me of carrying 4
it into effect, I wish it to be understood that I am well aware that timber roofing
composed of boards overlapping each other is old and well known, but that what I
believe to be new, and claim under the herein part before in part recited Letters
Patent is,―
1st. The construction of roof coverings composed of boards of timber or other 5
long flat plates with their edges turned up, or with a piece projecting on each edge
interlocking with the projection on the next board.
2nd. The construction of timber sheathing of boards, having projecting strips on

page_text: their edges, so arranged that the strip of one board interlocks with the strip on the
next, as described.
3rd. The general arrangement of roof coverings and of timber sheathing, sub-
stantially as described.
In witness whereof, I, the said William Henry Kershaw, have hereunto set my
hand and seal, this Twenty-fourth day of May, in the year of our Lord
1877.
WILLIAM HENRY (L.s.) KERSHAW.