Ancient Preservation Methods
The oldest known wood preservation technique is charring — burning the surface of a post or beam to create a carbonized layer that resists rot and insects. The Japanese practice of Shou Sugi Ban (yakisugi) has been used for over 700 years and is experiencing a revival in modern architecture. We occasionally char reclaimed boards as a finishing technique at customer request.
The Vikings used pine tar to waterproof their ships. Medieval builders soaked timber in seawater or urine. Egyptian coffin makers used cedar oil and natron. Each civilization developed preservation methods suited to their available materials and building needs.
Industrial Era
The 19th and 20th centuries brought chemical preservation at industrial scale. Creosote (coal tar distillate) was patented in 1838 and became the standard treatment for railroad ties, utility poles, and marine pilings. CCA (chromated copper arsenate) was introduced in the 1930s for residential applications.
Much of the reclaimed lumber in circulation today was never chemically treated because it came from buildings where treatment was unnecessary — interior framing, floor joists, roofing, and paneling in dry environments. This is actually an advantage: untreated reclaimed wood is safe for any application, including food-contact surfaces and children's spaces.
Modern Best Practices
Today's best wood preservation methods focus on non-toxic, environmentally responsible approaches. Penetrating oil finishes (tung oil, linseed oil), borate treatments for insect prevention, and heat treatment for export compliance (ISPM 15) all protect wood without introducing hazardous chemicals.
For reclaimed lumber, the most important preservation step is proper moisture management. Wood that stays dry does not rot. Ensuring adequate ventilation, maintaining protective finishes, and avoiding ground contact are more effective than any chemical treatment.