TM 5-822-5/AFM 88-7, Chap. 1
decreasing the insulation thickness and repeating the
provide means for passage of water through the
process outlined above.
insulation to avoid possible excess hydrostatic
pressure in the soil on which the insulating material
is placed. Free drainage may be provided by leaving
D-5. Construction Practice.
the joints between insulating boards slightly open,
While general practice has been to place insulation
or by drilling holes in the boards, or both.
in two layers with staggered joints, this practice
HQUSACE (CEMP-ET) or the appropriate Air
should be avoided at locations where subsurface
Force Major Command may be contacted for more
detailed construction procedures.
experienced. In the latter cases it is essential to