For a properly ventilated space and/or with a working dehumidification system, wood in enclosed spaces with full roof cover need not be preservatively treated.
Sentinel Structures, Inc. "Ventures in Wood", in words and pictures illustrate -
You may find Pressure Preservative Treatment of Structural Glued Laminated Timber at the National Maritime Museum Association, address http://www.maritime.org/conf-rhude.htm.
For further information, reference the American Institute of Timber Construction (AITC) Standard 109 or the McGraw-Hill Standard Handbook for Civil Engineers, Fourth Edition, Section 11 "Wood Design and Construction".
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