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

292 CORK INSULATION
that the forms are reasonably even. Lay down the first row '.
of corkboards on the forms, along one side of the ceiling area,
in a straight line. Keep the corkboards in perfect alignment, i
so that the joints in the rows to follow may fit close and tight. I
If the surface of the forms should be slightly uneven, se- j
cure the corkboards to the forms with a few headless finishing I
nails, which will easily pull out of the corkboard when the
forms are removed. Break all joints between the different :
rows, by starting alternate rows with half-length boards, and i
see that all joints are butted close and made tight, so that
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none of the concrete can run down between the corkboards I
and pieces of corkboard when the concrete is poured. When !
the opposite end and the opposite side of the ceiling area is
reached, cut pieces of corkboard neatly to fit the outline of
the forms. !
Drive three galvanized wire nails per square foot obliquely
into the corkboard and leave the heads protruding about V/2 ]
inches to afiford an additional key for the concrete, and leave ,
the <strong>insulation</strong> in readiness for the concrete contractor to pour 1
the ceiling slab. !
After forms have been removed, permit this layer of cork-
board on underside of concrete ceiling to dry out thoroughly,
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not less than an additional 48 hours, before erecting another '
layer of corkboard against the first, or before applying a finish ;
over the <strong>insulation</strong>.
126.—First Layer <strong>Cork</strong>board, to Wood Ceiling, in Asphalt
Cement.—See that the ceiling presents a smooth, continuous,
solid surface, free from open cracks and loose or warped
boards, remove all dirt, plaster, paper, or other foreign material,
or arrange to have these several items taken care of by
those responsible for such preliminary work, before making
preparations to erect corkboard to wood ceiling in Asphalt
cement.
Prepare suitable Asphalt cement in reasonable quantity,
distribute it to heated pans, add the proper proportion of
cork dust and mix, dip one flat side, one end and one edge of
each corkboard in the molten material, lay up the first row
of corkboards to the ceiling surface and against the edge of
;
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