Wood as been a favorite home construction material over the years, thanks to its beauty and overall durability. No wonder everything is being done to care for it and prolong its life, such as wood preservers
Termites, fungi and wood-boring insects are timber’s three worst enemies. Fortunately, protection is possible through various types of natural and synthetic wood preservatives and treatments today.
Types of Wood Preservatives
Chromate Copper Arsenate
Chromium copper arsenate is a pesticide that strengthens wood against fungi, termites and other pests. It has been a popular wood preservative for over 50 years. One concern raised by the United States’ Environment Protection Agency, however, is that arsenic may leak out over time and endanger the health of those who are exposed to it.
To control risks linked to wood treatment in general, the American Wood Protection Association recommends that treated wood be sold with a Consumer Information Sheet, where instructions on safe handling and disposal are provided. Many manufacturers, however, prefer to provide Material Safety Data Sheets over CIS. There is a never-ending debate on this practice of distributing information regarding treated wood, but the more important point is that the consumer is fully aware of the product.
Oil-Borne Wood Preservatives
Two very common oil-borne preservatives today are creosote and pentachlorophenol. Creosote has been widely used in history as a treatment for railroad ties, bridgework and other outdoor applications. In this method, the timber is placed in a sealed chamber, and a vacuum sucks out the air and moisture out of the wood. The creosote is then applied through a pressurized method. Pentacholorphenol, an organochlorine compound, is both a pesticide and a disinfectant rolled into one. It can be applied to wood by spraying, dipping or brushing, by soaking the wood in the liquid, or by pressure.
Water-Borne Wood Preservers
Water-based preservatives are some of the cheapest you’ll find in the market, but because of their water content, they tend to cause wood to swell or warp. Two examples of water-based wood preservatives are alkaline copper quaternary compounds and copper.
A rising trend in the industry of wood preservation is the creation of alternative methods that are more environment-friendly, such as acetylation and heat treatments. When subjected to extremely high temperatures in the absence of oxygen, timber becomes inedible to insects and microorganisms due to the resuling alterations in its chemical makeup.
Instead of infusing water-based preservatives into wood through pressure, acetylation chemically changes wood by reducing moisture in its cell wall enough that fungal degradation becomes impossible. This makes the wood not just stronger but termite-resistant too, being harder and drier than its unmodified counterpart.