Cork insulation; a complete illustrated textbook on cork insulation ...

CHAPTER XII.
PROPER THICKNESS OF CORKBOARD TO USE
AND STRUCTURAL SUGGESTIONS.
89.—Economic Value of Insulating Materials.—During the
past fifteen years or so there has been considerable time and
attention given to the study of insulating materials, both
theoretical and practical ; but the results have taken the form
of the determination and comparison of the thermal efficiency
of many materials, and the best methods of erecting and
caring for them in service, rather than having dealt with the
determination of the range of profitable expenditure which is
the real aim and end of industrial research. In the absence
of any concrete information of generally recognized worth on
the subject of how much money it is advantageous to expend
for cold storage <strong>insulation</strong>, the users of such materials have
divided into two main classes : First, those who came to
believe that it was not profitable to employ as much insula-
tion as generally recommended by responsible manufacturers,
or who came to believe that cheaper materials in the same
thicknesses would suffice ; and, secondly, those whose experi-
ence and judgment taught them that increased thicknesses of
only the best insulating materials were profitable to install.
Those in the first class are much in the minority, yet
their numbers justify careful consideration of their policy.
It might be expected that a third class exists, consisting of
those who have not changed their <strong>insulation</strong> ideas and prac-
tices during the period of time mentioned ; but it is believed
that these are now so few in actual numbers as to be of no
real importance with respect to a discussion of this subject.
The true economic value of an insulating material must, of
course, follow rather closely a consideration of the monetary
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