The Mankato free press. [volume] (Mankato, Blue Earth County, Minn.) 1879-1924, 1883-01-05
Tar Roofs for Farm Bu;ldines

Tho London Builder says that the
German government has ON several oc-
.asions pointed out to farmers and 9th
crs Interested in agriculture that too
great an expenditure Of capital on
buildings Is n mistake. With view Of
illustrating the application of this prin-
ciple Of economy to roofing. The Cologne
Gazette points out that the system ut
using tar for roofing purposes is mt tho
same time economical and suitable for
agricultural buildings. The framework
Of the roof can be of relatively slight
construction on account Of the nature OF
the covering it il intended to support,
and the perpendicular height OF the
roof can be onc-eighth to one-tenth Of
the entire depth Of the building. The
distance of the rafters is arranged ac-
cording TO the width of the covering
material, the scale being that from the
middle of one rafter To the middle of
another. the distance should be %
inches less than the width of tar roofing
sheets.
Immediately upon the rafters come
boards, and upon these (exactly In the
center Of the separate rafters) arc placed
strong laths, about , inches wide and
! inches thick, the upper edges being
taken of. The roofing sheets are now
placed so rs to cover the spaces between
the laths. and nailed. Over the laths
are placed strips Of paper, inches 10 q
inches wide, fastened with nails ut in
tervals of u inches.
In order to make the sheets lie
smoothly upon the boarding it is sug-
gested, in case they arc too dry, to soft
en- them by immersion in water. 1t Is
recommended that the workman should
not wear heavy-nailed boots, and also
that If the rain comes on. the roof
should not be walked upon Immediately
after. When the entire surface of the
roof Is covered with sheets, the strips of
paper Cor caps) already named, Us well
rs the joints. are painted over with a
hot mixture of coal tar and pulverized
lime. Pure, dry sand is 1T once sprink-
led over this coating. and particular
care must be taken that all the nail
heads are well covered. When the paint
is dry the whole surface of the roof il
once more coated with the same mix
ture. and is sanded.
The object of this careful method Of
OVERLAPPING the roof with several coat
ings of specially-preparcd solutions is
to preserve in the tar those oleaginouJ
and fatty properties which it soon loses
il exposed to the air. and the retention
of which is I'm indispensable condition
OF its resistance to water. Clay and
sand do not afford sufficient protection.
and they are removed by violent winds.
Reference il made to various systems
of coating the tar roof with protective
substances, for the purpose indicated.
| One Of the most successful methods
consists of mixture of cowdung and
thin. white. lime, which is spread over
the entire surface of the roof. II such a
coating is not applied the tar paint
must. during the first four years, be an
nually renewed, which enhances the
cost of the roof. Ii the last named pro.
tective composition is used. and renew
ed every two years. the coating of tar
and lime can be dispensed with. Par.
ticular mention is. however. made of q
coating of tar mixed with Portland CO.
ment, the tar being well heated aud
used in the proportion of Ill pounds to
200 pounds of cement. The mixture
should be kept well stirred during the
preparation. and should be applied as
soon as made. This particular method
has been tried in many cases in Ger
many. and. according To the journal
quoted from, its satisfactory result.
have caused its adoption upon scale
of progressive Importance.