WHAT ARE FIELD-APPLIED PRESERVATIVES AND WHAT TYPES ARE AVAILABLE?
Field preservatives are chemicals that are applied to cut pieces of treated wood at the construction site, and they should be purchased along with treated wood as they will inevitably be required. Field preservatives must be applied when treated lumber is cut in the field, as the cut will expose untreated wood at the core of the piece. Most field preservatives come in a liquid form and can be separated into two groups: organic solvent and water-soluble. The organic solvent preservatives are typically used for field-treating cut ends of pressure treated wood. There are two available chemicals in this category: copper naphthenate and zinc naphthenate. Of the two, copper naphthenate is more effective and can be used in all applications. Copper naphthenate is green. Zinc naphthenate is somewhat less effective, so its use is restricted to above-ground applications only; it should not be used on wood that will be in ground contact. Zinc naphthenate is available either colourless or colour-ma
