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

STRUCTURAL SUGGESTIONS 207
so, they must be carefully and thoroughly cleaned before it is
possible to apply corkboard <strong>insulation</strong> to them successfully.
Such cleaning must usually take the form of hacking, which
is a difficult job in most instances, and considerable care must
be exercised if the finished work is to be satisfactory.
After the <strong>complete</strong> area of such walls has been hacked, or
otherwise prepared as required, it will often be found that
their surfaces are sufficiently irregular to require pointing
up, unless the first kn^er of <strong>insulation</strong> is to be erected in a
bedding of Portland cement mortar, and sometimes even then.
On the other hand, if the purpose of the insulated room or
structure makes it imperative that the first layer of <strong>insulation</strong>
be erected in hot asphalt to walls that have first been primed
with suitaljlc asphaltic material, then the pointing up work
must take the form of a <strong>complete</strong> leveling and smoothing up
of the areas to be insulated ; because the thickness of the hot
asphalt that clings to the sheets of corkboard when they are
dipped, is quite insufficient to be relied upon for anything
except a bond, and a uniformly full bond is not possible except
against reasonably smooth, flat surfaces. Furthermore, if the
primed surface to which the sheets of corkboard are applied
is unexcn. the surface of the finished cork work will be just
as much, or possibly more, uneven, and may seriously inter-
fere with the making of tight <strong>insulation</strong> joints and with the
proper interior room finish over <strong>insulation</strong>, not to mention
the air pockets behind the corkboards. Consequently, the
cost of proper preparation for <strong>insulation</strong> to be applied in
existing structures and following the most approved specifi-
cations, is sometimes prohibitive, and an <strong>insulation</strong> specifica-
•tion less expensive must be selected or the project altered or
abandoned.
The preparation of surfaces in new structures to receive
<strong>insulation</strong> frequently does not have the forethought and atten-
tion that its importance justifies. Preparation should begin
with the drafting of the plans and specifications for the build-
ing itself; but smooth, even, brick walls on the architect's
drawings are not necessarily smooth, even, brick walls when
actually erected, unless thought is given to the functioning
of those walls other than their load-carrying and encompass-