FPL-GTR-217. This document provides guidance on wood preservation options in the context of historic preservation. Preserving wooden building materials is critical to historic preservation practitioners. Biodeterioration can be minimized through design, construction practices, maintenance, and, if necessary, by use of wood preservatives. Moisture is the primary cause of biodeterioration, and if exposure to moisture cannot be prevented, the application of preservatives or use of pressure-treated wood may be warranted. The Secretary of Interior's Standards for the Treatment of Historic Properties emphasize retaining the historic character of a property, including distinctive materials, features, and spatial relationships. Existing conditions should be carefully evaluated to determine the appropriate level of intervention.