Is there pressure-treated wood that isn't treated with chemicals?
I'm looking for no treatments to the wood.
The short answer is no.
Although some of the more toxic chemicals have been removed for specific uses, such as residential uses versus industrial or commercial uses, they still all contain chemicals. The American Wood Protection Association (AWPA) has set standards for types of chemicals that are used in pressure-treated lumber and their acceptable uses. This standard has reduced the incidence of manufacturers using even more toxic chemicals in their products, and has set guidelines for types of pressure-treated lumber.
The list below from the AWPA shows the types of lumber and the chemical content of each.
Code Preservative Name:
- ACC Acid Copper Chromate
- ACQ Alkaline Copper Quaternary (Type B or C)
- ACQ Alkaline Copper Quaternary (Type A or D)
- ACZA Ammoniacal Copper Zinc Arsenate
- CA-B Copper Azole, Type B
- CA-C Copper Azole, Type C
- CuN-W Waterborne Copper Naphthenate
- CX-A Copper
- HDO EL2 DCOI-Imidicloprid-Stabilizer
- PTI Propiconazole-Tebuconazole-Imidicloprid
- PTI plus stabilizer
- SBX inorganic Boron (Formosan termites)
- SBX inorganic Boron (non-Formosan termites)
You can get more information about the specific preservatives from the information for homeowners page on the AWPA website.